CULTURAL AND BIOLOGICAL CONTROL TACTICS FOR SPOTTED -WING
DROSOPHILA IN ORCHARD SYSTEMS POST-HARVEST

By

Charlotte Mae Johanna Schuttler

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of
Entomology – Master of Science
2023



ABSTRACT
Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is an invasive, polyphagous vinegar
fly with high fecundity and short generation time. Drosophila suzukii, or ‘spotted-wing
Drosophila’ has spread quickly across the United States and has quickly become the main pest of
concern in tart cherry production. Millions of dollars are spent each year on chemical and labor
costs to address this invasive pest. Current management tactics rely upon multiple applications of
broad-spectrum insecticides. As populations of D. suzukii resistant to spinosyns and pyrethroids
have recently been found in California, alternative management strategies are needed to reduce
dependency on chemical control. Recent releases of classical biological control agents have
begun across the United States, but their ultimate establishment and potential impact is yet
unknown. Innovative methods of cultural and biological control could help restore integrated
pest management (IPM) of D. suzukii in cropping systems. This thesis investigates cultural
control and biological control methods for managing D. suzukii infestation in post-harvest fruit
waste as means of reducing overall populations within an area and potentially decreasing the
need for other management methods. Orchard systems often manage disposal of post-harvest
crops consisting of any ripe, overripe, and decomposing fruit which may function as a
reproductive source for pests. Crushing fruit or adding 15% or 25% organic poultry manure by
volume were identified as effective cultural control methods of decreasing the number of D.
suzukii and non-suzukii drosophila on post-harvest cherry waste. Adding Hermetia illucens
(Linnaeus) (Diptera: Stratiomyidae) larvae to D. suzukii infested fruit waste was found to limit
D. suzukii infestation. These cultural and biological control methods can be integrated into
existing management programs to help reduce in situ populations of D. suzukii without further
addition of insecticides.



Dedicated to Carolyn Schuttler

iii



ACKNOWLEDGEMENTS
I would like to thank Hannah Burrack for taking me as a student even though she had enough on
her plate, for always lending an ear and a new way to think about things, and for encouraging a
life-work balance. Thank you to Matthew Grieshop for giving me many opportunities to continue
learning, and many tools to be successful. Thank you to Juan Huang for her assistance and
mentorship over many years, without which I would be lost. Thank you to Holly Hooper for
showing me how to be a scientist. I would like to thank the members of my committee (Matt
Grieshop, Nikki Rothwell, Marianna Szucs, and Hannah Burrack) for their different
perspectives, patience, understanding, and tenacity for research. Thank you to the many (past and
present) members of the Organic Pest Management Lab, the Pollinator Lab, and the Tree Fruit
Entomology Lab. I would like to thank the many technicians who assisted me in laboratory and
field work, especially Maggie Foley and Robin Fisher. I want to thank the members of the
Northwest Horticulture Research Center especially Nikki Rothwell, Karen Powers, Jen Zelinski,
Myron Anderson, and Bill Kline for their hard work, dedication, and for being my ‘Up North’
home. I would like to thank my grower collaborators, Gene Garthe and Garthe Farms, and
Cherry Bay. Thank you to Jim Koan and Almar Orchards, Amy Herbruck and Herbruck’s
Poultry, Jonathan Cammack at Evo Conversion Systems, and Chelsea Holcomb and Jeffery
Tomberlin at Texas A&M. Thank you to my funding sources, NCSARE and Project GREEEN,
for making this research possible. Thanks to my mom, Carolyn Schuttler for always encouraging
me. Thanks to my dogs for keeping me company. Finally, thank you to Nate Alto for being my
babe.

iv



TABLE OF CONTENTS
CHAPTER 1. FARM-SCALE ASSESSMENT FOR MANAGING DROSOPHILA
SUZUKII INFESTATION OF POST-HARVEST FRUIT WASTE……………………….....1
CHAPTER 2. NITROGEN BASED FERTILIZER APPLICATION TO LIMIT
DROSOPHILA SUZUKII INFESTATION OF FRUIT AND FRUIT WASTE…………….23
CHAPTER 3. SURVIVAL OF DROSOPHILA SUZUKII FOLLOWING HERMETIA
ILLUCENS CO-INFESTATION………………………………………………………………35
LITERATURE CITED………………………………………………………………………...48
APPENDIX A. RECORD OF DEPOSITION OF VOUCHER SPECIMENS……………...58
APPENDIX B. CHAPTER 1 SUPPLEMENTARY MATERIAL…………………………...59

v



CHAPTER 1. FARM-SCALE ASSESSMENT FOR MANAGING DROSOPHILA
SUZUKII INFESTATION OF POST-HARVEST FRUIT WASTE
Introduction
Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a vinegar fly of eastern
Asian origin, which has recently undergone a dramatic global range expansion (Asplen et al.
2015). Drosophila suzukii prefer to lay eggs in soft-skinned fruit such as blueberries and
caneberries but will utilize a range of crop hosts including strawberries, cherries, and damaged or
spoiled fruit (Walsh et al. 2011, Burrack et al. 2013). Eggs are laid under the surface of ripe and
ripening fruit, and larvae develop internally which can result in larval infestation in harvested
fruit. Development from egg to adult can take as little as 8 days with adults living for up to two
weeks (Lee et al. 2011). This quick development results in rapid population growth and multiple
overlapping generations of D. suzukii each summer, making pest management difficult (Lee et al.
2011).
The arrival of D. suzukii to the United States has caused millions of dollars’ worth of
losses in multiple crops (Bolda et al. 2010). Drosophila suzukii was detected in Michigan in
2010 and quickly became the key pest of tart cherries (Wilson et al. 2019). In the Midwest
United States, tart cherries (Prunus cerasus, Rosales: Rosaceae) are marketed from June 25th to
August 15th (NASS 2023). The large, serrated ovipositor of the female D. suzukii means that
cherries are at risk of infestation from the moment the fruit begins to gain color throughout
harvest (Wilson et al. 2019). Michigan is the main U.S. state growing tart cherry, producing 43.8
million kilograms out of the United States total of 780,179 kilograms (~56%) in 2021 (NASS
2023). In 2021 there were 9307.8 hectares (23,000 acres) of tart cherries grown in Michigan
producing a crop valued at $58 million dollars (NASS 2023). Prior to the establishment of D.
suzukii in Michigan, the major tart cherry pests included the cherry fruit fly Rhagoletis
1



cingulate (Loew) (Diptera: Tephritidae), black cherry fruit fly Rhagoletis fausta (Osten Sacken)
(Diptera: Tephritidae), plum curculio Conotrachelus nenuphar (Herbst) (Coleoptera:
Curculionidae), and the American plum borer, Euzophera semifuneralis (Walker) (Lepidoptera:
Pyralidae), which were managed with detection based sprays from early May until pre-harvest at
the end of July (Brown et al. 1989, Sirrine 2006, Michigan State University Extension 2004) As
observed in other crops (Joshi et al. 2022), pre-harvest insecticide use in tart cherries has
increased following D. suzukii establishment in Michigan to meet strict no-tolerance
requirements for fruit infestation.
Organophosphates, pyrethroids, and spinosyns are among the most effective classes of
insecticides against D. suzukii, and years of increased used has raised concern for resistance
development (Fanning et al. 2018, Van Timmeren and Issacs 2013, Mishra et al. 2018).
Resistance to spinosyns and pyrethroids has already been observed in California populations of
D. suzukii (Gress and Zalom 2019, Ganjisaffar et al. 2022). Growers are interested in nonchemical control tactics to reduce populations of D. suzukii and decrease reliance on insecticides.
Innovative cultural control techniques have the potential to limit additional insecticide use and
could help restore integrated pest management in small fruit production. Drosophila suzukii are a
mobile pest which will show flexible preference when whole fruit are not available (Kirkpatrick
2018, Kienzle et al. 2020). Management techniques which target other potential resources like
fruit waste, could limit in situ populations.
Fruit waste may consist of infested fruit, damaged fruit, and unripe or overripe fruit.
Massive amounts of fruit pomace left over from juice, cider, and wine production end up in
landfills or composting sites (Dhillon et al. 2013). From 2021to 2022, approximately 0.2 million
tons of apple pomace and 1.3 million tons of wine pomace were produced in United States, the

2



physical equivalent of 214 thousand adult African elephants (Jackson et al. 2022, Ferrer-Gallego
and Silva, 2022). Market conditions for tart cherries lead to the periodic disposal of large
amounts of fruit which cannot be sold (Paggi and Nicholson 2013). Disposal of fruit waste may
include piling in unused fields, composting, feeding to livestock, and landfilling (Esparza et al.
2020). Unprocessed fruit waste can provide late season resources for multiple drosophila species
and other pest insects and create early season pressure the following season (Bal et al. 2017).
Treatment of post-harvest waste may also reduce other nuisance pests. Sap beetles
(Coleoptera: Nitidulidae) are attracted to overripe, rotting fruit; are considered potential pests in
strawberry, sweet corn, melon, peach, raspberry, blueberry, and cherry; and are a major pest of
berries in the Northeastern United States (Loughner et al. 2007). Multiple sap beetle species are
found in fruit and function as a pest complex (Powell 2015, Rondon et al. 1969). Sap beetle
adults are attracted to fermentation odors and will directly feed and lay eggs in both rotting and
sound fruit (Powell 2015). Sap beetle generation time is roughly four weeks, and more than one
generation occurs per growing season (Emekci and Moore 2015). Larval sap beetles cause
damage by feeding on fruit, contaminate fruit through their presence, and facilitate further
infestation by secondary pests such as Drosophila spp. and phytopathogens (Rondon et al. 1969,
Souza et al. 2019, Lin and Phelan 1991). Prompt removal of ripe fruit from fields reduces their
attractiveness to sap beetles (Loughner et al. 2008).
Volatiles from ripe and fermenting fruit attract more than just sap beetles, particularly
non-suzukii drosophila species such as Drosophila melanogaster (Meigen), D. simulans
(Sturtevant), D. hydei (Sturtevant), D. busckii (Coquillet), and D. robusta (Sturtevant)
(Sturtevant 1921, Band 1993). These non-suzukii drosophila species have a similar life span to
D. suzukii but are unable to infest undamaged fruit pre-harvest, and while mostly a concern for

3



damaged fruit post-harvest, can cause pathogen spread in fruit production and infest products
during processing (Hubhachen et al. 2022). Previous research has found D. melanogaster
populations in Michigan have variable levels of resistance to multiple classes of insecticides,
highlighting the need for implementation of cultural management methods (Hubhachen et al.
2022).
My work seeks to develop strategies to reduce the ability of insect pests to utilize postharvest fruit waste by comparing several possible management tactics. Crushing fruit postharvest has been found to work at small scale to reduce D. suzukii infestation but has not
previously been examined at a farm scale (N. Rothwell, personal communication). Previous
research suggests that incorporating organic poultry manure into fruit waste at a rate of 25% by
volume will inhibit D. suzukii adult emergence by 95% (Hooper and Grieshop 2021). I
conducted a series of experiments comparing crushing, manure addition, or fertilizer addition
under field conditions to assess potential reduction of in situ D. suzukii populations and possible
impacts on other post-harvest pests. In addition to testing different concentrations of manure, I
also tested the addition of urea as a synthetic alternative to manure. To the best of our knowledge
this is the first study managing pest insects in post-harvest cherry waste, and we utilized multiple
evaluation methods in order compare them for potential future research. Therefore, a secondary
goal of this experiment was to evaluate sampling methods to determine which methods were
most effective.

4



Materials and Methods
2021 Experiment
We selected four treatments to apply to cherries post-harvest: (1) crushing, (2) incorporation of
25% manure by volume; and (3) incorporation of 15% manure by volume compared to (4) an
untreated control. Granulated organic chicken manure obtained from Herbruck’s Poultry Ranch,
Inc. (Saranac, MI) was used for manure containing treatments. Seven sites (Table B.1) were
chosen in the Leelanau peninsula (Michigan, USA) and one replicate of each treatment was
established per site. Cherries were harvested by cooperating growers and placed in selected sites.
Due to unfavorable conditions during the 2021 field season, there was limited availability of tart
cherries, so some locations utilized sweet cherries (Table B.1). At each location, cherries were
measured by volume with 5-gal plastic buckets and dumped into four piles. Each pile consisted
of 95 L of cherries (~73.5kg). Piles were spaced at least 100 m apart. For crushing treatments,
cherries were crushed with tractor tires until 90% of fruit was macerated then fruit was raked
back into a pile. For manure treatments poultry manure was measured and applied to waste piles.
Treatments with 15% manure had 13.2 L of water added, and treatments with 25% manure had
26.5 L of water added. All other treatments had 13.2 L of water added to them. All waste piles
were mixed for approximately 4 min with hand tools after treatments were applied to either
incorporate manure or to maintain conditions comparable to manure incorporation.
Insects coming from fruit piles and those from around fruit piles were monitored. To
capture insects emerging from fruit waste, each pile was capped with an emergence cage
(Bugdorm, Talchung, Taiwan) measuring 60 cm L by 60 cm W by 60 cm H, secured at four
points with ground stakes. The whole experiment took place between July 15th and August 24th ,
2021, with all sampling starting on July 22nd , 2021. The inside of each emergence cage was

5



vacuumed twice weekly using a handheld aspirator (BioQuip Products, Inc., Rancho Dominguez,
CA). Aspirated samples were frozen for at least 24 h, after which the number of male D. suzukii,
female D. suzukii, non-suzukii drosophila, and sap beetles (Coleoptera: Nitidulidae) were
counted under a stereomicroscope.
To monitor insects on and around fruit waste piles, we used three yeast-baited cup traps
(Huang et al. 2017). All traps were suspected from 0.91m stakes and placed either directly next
to each fruit waste pile (trap E) or 10 m from the pile in opposite directions (traps N & S). Yeast
trap contents were collected weekly, filtered, and D. suzukii, non-suzukii drosophila, and sap
beetles were sorted and counted.
2022 Experiment
A second field season was completed in 2022 following similar methods to 2021. Plots
were established at five locations (Table B.1). In 2022, tart cherries, cv. Montmorency were
harvested from the Northwest Michigan Horticulture Research Station (Traverse City, MI),
moved to each location, and divided into piles. In addition to the treatments compared in 2021,
the following treatments were added during 2022: (5) A D. suzukii seeded control and (6) a urea
fertilizer treatment. Urea was added with the intent to isolate the effect of nitrogen addition on D.
suzukii infestation. Drosophila suzukii used to infest the seeded control were from a colony
established in 2016 from flies collected from the Trevor Nichols Research Center (TNRC) at
Michigan State University (Fennville, MI). Flies were reared on corn meal diet (Dalton et al.
2011) in 300 ml wide mouth glass mason jars (Ball Corporation, Broomfield, CO) and
maintained in a growth chamber set at 21˚C, 70% relative humidity (RH), and a photoperiod of
16:8 (L:D) hours. Flies were anesthetized using CO 2 and separated by sex on a FlyStuff FlyPad
(Genesee Scientific, San Diego, CA). Following separation, females were placed in new jars of

6



diet for two days prior to field release. Flies were released into the center of emergence tents
immediately after setting up and left in for the entirety of the experiment. Urea fertilizer (The
Andersons, Inc., Maumee, OH) was measured and mixed with water and the solution was
dumped onto piled fruit. All piles were mixed for approximately 4 min by shovel before tents
were added.
The 2022 experiment took place between July 22-August 24th , 2022. Sampling began on
July 25th, 2022. Yeast cup captures were used to assess insects near fruit piles following the
same methods as in 2021. To measure insects emerging from piles within cages, vacuum samples
were collected as in 2021, and in addition, a single yellow sticky card was hung inside each cage
and was replaced weekly. Sticky cards were stored at -20°C after collection until the number of
D. suzukii, non-suzukii drosophila, and sap beetles could be enumerated.
Statistical Analysis
All statistical analyses were conducted using SAS version 9.4 (SAS Institute Inc., Cary,
NC, USA). Vacuum samples, cup trap captures, and yellow sticky card captures for all target
insects were all compared via a mixed model ANOVA fitted to a logistic distribution via Proc
GLIMMIX. A constant of 1.5 was added to response variables to retain zero values in the
analysis. Site was included in models as a random effect, and treatment and week of experiment
were considered fixed effects. In instances where there were significant effects of independent
variables or their interactions, pairwise mean comparisons were conducted using the TukeyKramer adjustment with α=0.05. In cup traps insect counts from traps N and S were averaged
and compared against the corresponding trap E and across treatments.

7



Results
Drosophila suzukii
Analyzed means of D. suzukii collected in vacuum samples during 2021 (Figure 1.1A)
showed significant effects of treatment (F 3,138 =4.29, p=0.0063), week (F5,138 =4.79, p=0.0005)
and their interaction (F15,138 =2.03, p=0.0170). Capture was not significantly different between
treatments from week 1 to week 3. From week 3 to week 6, significantly more D. suzukii were
collected from the control treatment than in crushed, 15% manure, or 25% manure treatments.
Highest overall capture occurred in week 4 of the experiment and an average of 143 ± 96, 2 ±
0.2, 3 ± 0.8, and 3 ± 1.4 adult D. suzukii were collected from the control, crushed, 15% manure,
and 25% manure treatments, respectively.
Vacuum captures of D. suzukii in 2022 did not differ between treatments (F5,111 =1.42,
p=0.2226), week (F4,111 =0.87, p=0.4852), and there was no interaction between week and
treatment (F20,111 =0.68, p=0.8417). Sticky traps were added within emergence cages in 2022 as
an additional form of data collection. Numerically, more D. suzukii were caught in sticky traps
(2256) than in vacuum samples in 2022 (63). Based on catch from vacuum samples in 2021
(1685), it is likely that the addition of the sticky card inside the tent interacted with vacuum
capture in 2022.
Analyzed sticky trap capture of D. suzukii in 2022 (Figure 1.1B), showed that treatment
(F5,88 =14.64, p<0.0001), week (F3,88 =14.56, p<0.0001), and their interaction (F15,88 =2.66,
p=0.0023) were significant. Similar to vacuum capture in 2021, for the first 2 weeks of the
experiment there was no significant differences in capture between treatments, but in week 3
there were more D. suzukii caught in the control treatment than in all other treatments. In week 3,
an average of 98 ± 40, 37.3 ± 11.3, 15.7 ± 7.9, 21.5 ± 7.5, 5 ± 1.9, and 3.1 ± 0.9, adult SWD

8



were collected from the control, seed control, crushed, urea, 15% manure, and 25% manure
treatments, respectively.
In 2021, the most D. suzukii per week were captured in cup traps associated with 15%
manure (26.4 ± 0.2) treated piles as compared to crushed cherries (14.4 ± 0.2) or control (15.1 ±
0.2) treatments(treatment: F2,234 =3.90, p=0.0095; Figure 1.2A). The number of D. suzukii caught
in 25% manure (18.7 ± 0.2) and 15% manure (26.4 ± 0.2) treatments were not significantly
different from each other. Drosophila suzukii capture increased from week 1 to week 3, declined
in week 4, and increased again in week 5 (week: F4,234 =57.62, p<0.0001). There were no
interactions between experimental week and treatment (F12,234 =0.62, p=0.8240). In 2021, nearly
twice as many D. suzukii were captured in cup traps placed on piles (10,532) than in traps placed
10m away (5896) from piles (F1,234 =4.14, p=0.0429) with no interaction between treatment and
trap placement (F3,234 =1.80, p = 0.1486).
A similar pattern was observed in 2022 cup traps (Figure 1.2B) where treatments
containing manure had the highest D. suzukii captures (15%: 65.8 ± 19.3 ; 25%: 65.3± 21.6).
(treatment: F5,180 =16.23, p<0.0001). There was no significant difference between control (5.2 ±
0.9), seeded control (15.0 ± 3.8), crushed cherry (10.4 ± 2.4), and urea treatments (4.6 ± 1.1). D.
suzukii capture increased from week 1 to week 3 and declined in week 4 (week: F3,180 =31.83,
p<0.0001), but there was no interaction between week and treatment (F15,180 =0.87, p=0.6036).
There was a significant interaction between trap placement and treatment in 2022
(location*treatment: F5,180 =3.70, p = 0.0032), but this only affected the 15% manure treatment in
that more flies were captured in traps located on the pile. Traps placed on and off piles captured
similar numbers of flies for all other treatments.

9



Figure 1.1 A) Mean D. suzukii (±SEM) captured per treatment collected via vacuum during
2021 field season. B) Mean D. suzukii (±SEM) captured per treatment captured via sticky card
within emergence cages during 2022 field season.

Figure 1.2 Adjusted mean D. suzukii (±SEM) collected per treatment per week via cup trap in
(A) 2021 and (B) 2022 averaged across all three traps per replicate. All figures show significance
with α=0.05.
Non-suzukii Drosophila
Other Drosophilidae species observed included Drosophila melanogaster (Meigen),
Drosophila simulans (Sturtevant), Drosophila hydei (Sturtevant), Drosophila busckii (Coquillet),
and Drosophila robusta (Sturtevant). Non-suzukii drosophila capture via vacuum in 2021
differed significantly by week (F5,138 =10.96, p<0.0001), treatment (F3,138 =22.09, p < 0.0001), and
their interaction (F15,138 =2.27, p = 0.0069; Figure 1.3A). The control and crushed treatments had
a similar number of Drosophila captured in the first and second week of the experiment. In
weeks 3 and 4, the most non-suzukii drosophila were caught in the control treatment. Capture
declined in week 5 at which point all treatments had a similar amount of non-suzukii drosophila.

10



Vacuum capture in 2022 of non-suzukii Drosophila spp. (Figure 1.3B) differed
significantly between week (F4,111 =12.39, p<0.0001), treatment (F5,111 =74.36, p < 0.0001), and
their interaction (F20,111 =4.01, p = 0.0069). In the first week of the experiment, there was no
significant difference between treatments. By the second week, the control treatment had the
most drosophila with numbers peaking in week 3 and decreasing in week 4, similar to capture in
2021. The urea treatment (83.5 ± 41.1) had less capture than the control treatment (192.9 ± 90.1)
but more capture than the manure treatments (15%: 7.7 ± 5.2; 25%: 3.9 ± 1.4). Catch in the crush
treatment increased from week 1 to week 2, but by week 3, declined to rates similar to those of
manure treatments (crushed cherry week 3: 44.9 ± 16.6).
Sticky card capture in 2022 (Figure 1.3C) differed by treatment (F5,88 =57.16, p<0.0001),
week (F3,88 =16.51, p<0.0001), and their interaction (F 15,88 =3.81, p<0.0001). The control
treatment and seeded control were not significantly different at any timepoint and had highest
captures throughout the experiment. Capture in the urea experiment increased steadily
throughout the experiment. The crushed treatment had a similar pattern to 2021 and 2022
vacuum samples with a decline in capture from week 2 to week 3, and low capture throughout
the rest of the experiment, similar to capture in manure treatments. In week 3, an average of 83.6
± 28.9, 58.4 ± 9.3, 24 ± 7.4, 51 ± 13.9, 12.8 ± 9.4, and 4.4 ± 0.5 non-suzukii drosophila were
collected from the control, seed control, crushed, urea, 15% manure, and 25% manure
treatments, respectively.
In 2021 means of non-suzukii Drosophila spp. from cup traps showed no significant
treatment effect (F3,234 =1.47, p = 0.2245) and no interaction (week*treatment F12,234 =1.15, p =
0.3220). The number of non-suzukii drosophila did not steadily increase throughout the

11



experiment, but more non-suzukii drosophila were collected during the final week of the
experiment than earlier weeks across all treatments (week: F4,234 =3.40, p = 0.0100).
In 2022, significantly more non-suzukii drosophila were caught in cup traps associated
with piles containing 25% manure (6.1 ± 1.0) than those treated with urea (2.4 ± 0.5) or left
untreated (2.8 ± 0.6) (Figure 1.4; treatment: F5,180 =3.90, p=0.0022). Similar to vacuum samples
in 2021 and 2022, cup trap captures from the crushed cherry treatment started high in week 1
(14.7 ± 4.8) but declined in week 2 (2.7 ± 0.8) and remained low throughout the rest of the
experiment (treatment*week: F15,180 =2.02, p=0.0163).
In 2021 and 2022 twice as many non-suzukii drosophila were collected from cup traps
located on piles, rather than from traps 10m away from piles (2021: F1,234 =7.93, p = 0.0053;
2022: F1,180 =4.59, p=0.0335). There was no interaction between treatment and location of the cup
traps in 2021 (F3,234 =0.17, p = 0.9173) or 2022 (F5,180 =1.54, p = 0.1800).

12



Figure 1.3 A) Mean non-suzukii drosophila (±SEM) capture via vacuum in 2021. B) Mean nonsuzukii drosophila (±SEM) capture via vacuum in 2022. C) Mean non-suzukii drosophila
(±SEM) capture via sticky card sampling 2022. Note scale difference for 1.3C.

Figure 1.4 Mean non-suzukii drosophila (±SEM) capture via cup traps averaged across all three
traps per replicate in 2022.

13



Sap Beetles
Two morphospecies of sap beetle were observed in trap captures and vacuum samples,
and vouchers specimens of both have been deposited in A.J. Cook Arthropod Research
Collection at Michigan State University.
More sap beetles were collected in vacuum samples from the control treatment (1.0 ± 0.4)
as compared to the 15% manure (0.3 ± 0.4) treatment during 2021 (Figure 1.5A; F3,138 = 3.06, p
= 0.0304). There was no significant difference between the control(1.0 ± 0.4), crushed cherry
(0.6 ± 0.4), or 25% manure (0.4 ± 0.4) treatments. Sap beetle numbers increased as the
experiment continued, peaking in weeks 4 and 5 (F5,138 =7.12, p < 0.0001). There was no
interaction between week and treatment (F15,138 = 0.68, p = 0.8009).
In 2022, significantly fewer sap beetles were collected from vacuum samples from the
seeded control (0.00005 ± 0.3) as compared to other treatments (control: 2.6 ± 0.3, crushed
cherry:1.6 ± 0.3, urea: 2.5 ± 0.3, 15% manure:1.2 ± 0.3, 25% manure: 0.9± 0.3) (F5,111 = 7.33, p
< 0.0001; Figure 1.5B). More beetles overall were caught in week 4 (F4,111 = 7.62, p < 0.0001)
than in any other week, and there were no interactions between independent variables (F20,111 =
0.89, p = 0.5950).
The most sap beetles captured via sticky card in 2022 were caught in the crushed cherry
(14.3 ± 0.2), 25% manure (12.7 ± 0.2), and control (6.3 ± 0.2) treatments compared to the seeded
control (5.8 ± 0.2), urea (4.0 ± 0.2), and 15% manure (5.5 ± 0.2) treatments (F5,88 =4.98,
p=0.0005; Figure 1.5C). In 2022, the second week of the experiment had the most beetles caught
of all weeks (F3,88 =5.38, p=0.0019), and there was no interaction among independent variables
(F15,88 =1.01, p=0.4547).

14



Sap beetles captures in cup traps in 2021 did not differ between treatments (F3,234 = 2.38,
p = 0.0703), but did differ over time with significantly more beetles captured in the last (fifth)
week of the experiment, mirroring 2021 vacuum capture (week: F4,234 = 72.17, p < 0.0001).
There was no interaction between week and treatment (F12,234 = 0.35, p = 0.9777).
In 2021 (F1,234 = 5.39, p = 0.0211) and 2022 (F1,180 = 21.74, p < 0.0001) cup traps placed
10m away from piles captured 1.5 or 2.4 times as many beetles, respectively, as captured from
traps near piles. There was no interaction between location and treatment in either year (2021:
F3,234 = 0.92, p = 0.4333; 2022: F5,180 = 0.44, p = 0.8226). Cup trap capture associated with the
untreated control (1.7 ± 0.4) caught significantly more sap beetles than in 15% (0.5 ± 0.4) or
25% (0.7 ± 0.4) manure treatments in 2022 ( F5,180 = 3.90, p = 0.0022; Figure 1.6). In 2022, the
first week of the experiment had the most beetles caught of all weeks (F3,180 = 2.66, p = 0.0495),
and there were no interaction between week and treatment (F15,180 = 0.66, p = 0.8231).

15



Figure 1.5 A) Mean number of sap beetles (±SEM) per treatment caught via vacuum sampling
in 2021. B) Mean number sap beetles (±SEM) caught in vacuum sampling in 2022. C) Mean
number of sap beetles (±SEM) caught via sticky card in 2022. Note scale difference for 1.5C. All
figures show significance with α=0.05.

Figure 1.6 Mean number of sap beetles caught (±SEM) in cup traps in 2022, averaged across all
three traps per replicate. Significance shown with α=0.05.

16



Discussion
This research supports previous studies suggesting incorporation of poultry manure or crushing
as treatments to decrease D. suzukii emergence from post-harvest waste cherries (Hooper and
Grieshop 2021, N. Rothwell personal communication). Concentration of 15% manure or 25%
manure by volume added to waste cherries in the field were equally good at reducing D. suzukii
and other non-suzukii drosophila emergence. The mechanisms underlying this reduction are
currently unknown but could include direct or indirect fitness effects. High amounts of ammonia
and urea have been shown to be toxic to D. melanogaster and can affect the number of eggs laid,
egg viability, and overall development time, with D. suzukii showing greater sensitivity in lab
trials (Belloni et al. 2016). Nutrient addition may also alter the microbes present in waste fruit,
and microbial communities can influence D. suzukii host selection and performance (Bing et al.
2018, Hamby and Becher 2016) and those communities can in turn be influenced by D. suzukii
diet (Nikolouli et al 2022). For example, yeasts and other microbes have been shown to affect
larval development and affect oviposition preference in D. suzukii adults (Sato et al. 2021,
Bellutti et al. 2018).
We hypothesized that increased nitrogen in poultry manure was responsible for the
reduction of D. suzukii. To test this hypothesis, we used granulated soluble urea as a synthetic
nitrogen source at an amount equivalent to the nitrogen provided by 20% poultry manure by
volume. However, incorporation of urea fertilizer did not result in lower D. suzukii, other
drosophila species, or sap beetles in waste fruit when compared to manure treatments or
crushing. Future research should investigate other nitrogen-based fertilizers as a synthetic
alternative for manure composting as well as seek to quantify microbial communities throughout
fruit decomposition in treated and untreated fruit.

17



Crushing cherries was found to be as effective at reducing Drosophila suzukii and nonsuzukii drosophila species as incorporating poultry manure at 15% or 25% by volume.
Drosophila emergence from manure treatments was low throughout our experiments, but it took
2 to 3 weeks for crushed treatments to separate from untreated fruit. This delayed effect may be
due to the time it took crushed cherries to break down to the point at which they were no longer
able to support Drosophila spp. larvae. Drosophila suzukii pupate at a shallow depth
underground similar to many Tephritidae spp., which are negatively impacted by dry soil
conditions (Ballman et al. 2017, Hulthen and Clarke 2006, Montoya et al. 2008). Previous
research in blueberries correlated low humidity with reduced pupal survival, though larvae
located inside blueberries were not affected (Rendon et al. 2020). Crushing cherries likely
exposes pupae and larvae to desiccation and more efficient predation (Lee et al. 2019). Future
research could investigate larval and pupal exposure in crushed fruit and the likelihood of
desiccation based on location of waste and local weather. Crushing cherries may provide a
method of sanitation which targets multiple stages of Drosophila spp. and may be more cost
effective than adding fertilizer to fruit waste if appropriate equipment is available on location.
None of the treatments we investigated reduced sap beetle populations. When comparing
only between treatments, there is a general pattern over all sampling types and all years, with
most sap beetles captured in either the crushed or control treatments and the least sap beetles
captured in 15% manure treated piles. However, statistical analysis did not find consistent
differences between treatments across sampling types and years (Figure 1.5,1.6). Sampling
methods of Nitidulidae within this study are consistent with previously successful methods
comprised of vinegar or sugar-based cup traps, yellow sticky traps, and direct samples from
rotting fruit (Powell 2015, Williams et al. 1995, Peng and Williams 1991). Sap beetle generation

18



time is roughly four weeks, and 1 to 4 generations can occur during Michigan growing seasons
dependent on species (Emekci and Moore 2015). It is possible that insects caught in the first and
second weeks of the experiment were present as adults in harvested fruit, while those caught in
the fourth and fifth weeks may have been larvae at the time of harvest. Capture data shows that
more beetles were caught in cup traps away from waste piles regardless of treatment and week,
and our cup traps may have been attracting insects not associated with our waste fruit piles.
Our different sampling methods provided different types of information with respect to
all our focal insects. Cup traps were placed directly on waste fruit piles and around piles. These
trap captures provide information on insects attracted both to fruit waste and to the traps
themselves. Cup trap captures of D. suzukii were higher in 15% and 25% manure treatments than
in the untreated control, while vacuum samples and sticky traps captures of insects within
emergence cages were lower for these treatments. This may suggest that insects are more
attracted to the trap lure than the manure treated fruit waste when in close proximity.
Commercial cup trap lures which produce similar volatiles to the yeast baited traps used here
were shown to attract D. suzukii within 93m (Kirkpatrick et al. 2018). Therefore, it is also
possible that our cup traps were capturing D. suzukii to the general area. With respect to
monitoring insects emerging from waste piles within cages, sticky cards provided similar
information to vacuum samples and were easier to use and assess.
Nonchemical control tools are critically needed for D. suzukii. Resistance to multiple
classes of insecticides has already been found in D. suzukii and D. melanogaster in California
and Michigan, respectively (Hubhachen et al. 2022, Gress and Zalom 2019, Ganjisaffar et al.
2022). There is increasing research showing sanitation works to reduce ambient populations of
pest insects within agricultural production. The larvae of the navel orange worm, Amyelois

19



transitella (Walker) (Lepidoptera: Pyralidae) have been shown to use almonds as an
overwintering haven in California (Zalom et al. 1984). Similar to D. suzukii, A. transitella is not
controllable without insecticides, but post-harvest sanitation has been shown to reduce
infestation in future season when left over nuts are removed from the field (Higbee and Siegel,
2009, Zalom et al. 1984). When pigs were grazed in cherry plots plum curculio fruit damage was
significantly lower and in pear plots codling moth Cydia pomonella (Linnaeus) (Lepidoptera:
Tortricidae) and oriental fruit moth Grapholita molesta (Busck) (Lepidoptera: Tortricidae)
damage was significantly lower following the first year of the study (Buehrer and Grieshop,
2014). Research in raspberries has found that culled fruit should be removed or contained as D.
suzukii can emerge and infest clean fruit (Leach et al. 2018). Solarization can limit D. suzukii,
but that method is not practical for large amounts of fruit (Haye et al. 2016, Leach et al. 2018).
Fruit waste burial reduces D. suzukii emergence, but fruit must be buried 24 cm which is also not
practical for substantial amounts of fruit (Hooper and Grieshop 2020).
Our work investigates the treatment of post-harvest waste for instances when sanitation
within an orchard is unreasonable or cannot be replicated due to the amount of fruit. The tart
cherry market of the United States often requires the disposal of fruit to maintain market values.
The United States produced a total of 78 million kilograms of tart cherry in 2021 with a utilized
production value of $85.9 million dollars (NASS 2023). When considering fruit held back from
market, rejected due to infestation or imperfections, as well as fruit lost during harvest, this leads
to a lot of cherries in need of disposal. Of the 78 million kilograms of tart cherries produced in
2021, 136,077 kilograms were not sold (NASS 2023). Fruit waste may be fed to animals,
composted, or landfilled, but often disposal consists of piling in unused fields (Esparza et al.
2020). Multiple drosophila species and other pest insects can use unmanaged fruit waste as late

20



season resources for overwintering and create early season pressure the next year (Bal et al
2017).
Post harvest waste treatment may similarly contribute to an integrated management
system for D. suzukii. Post-harvest management and sanitation have potential benefit for
diversified farms growing multiple D. suzukii hosts by reducing ambient populations in early
season crops and is part of the management actions taken by sweet cherry growers in
Switzerland for D. suzukii (Schӧneberg et al. 2021, Hennig and Mazzi 2018). Whether postharvest treatment can effectively reduce populations the following year and thereby benefit large
scale monoculture planting is less clear. In the northern United States, low winter temperatures
cause significant D. suzukii mortality (Stockton et al. 2019), but not complete extirpation. In
Oregon, Washington, and British Columbia, CA, Drosophila suzukii were detected
overwintering in all regions and all years from 2010-2014, despite winter temperatures below 17°C (Thistlewood et al. 2018). D suzukii has also been shown to use fruit waste including
dropped fruits, wild fruit, and fruit compost as a reproductive resource before, during, and after
target crop season, but season to season population dynamics of D. suzukii remain poorly
understood (Lee et al. 2015, Bal et al. 2017, Ballman and Drummond 2017).
All current methods commonly used to manage D. suzukii are unable to completely
prevent yearly damage or eradicate this invasive pest. Incorporating sanitation of post-harvest
waste as part of regular integrated pest management programs can remove reservoirs of offseason reproduction and reduce pressure on susceptible crops later in the season. The results of
our work suggest that manure treatments and crushing reduce D. suzukii and other Drosophilidae
in post-harvest cherry waste. These tactics may be useful for diversified growers with later
season D. suzukii host in proximity to cherries, but additional research would be necessary to

21



determine if significant benefits from post-harvest treatments are realized in subsequent growing
seasons.

22



CHAPTER 2. NITROGEN BASED FERTILIZER APPLICATION TO LIMIT
DROSOPHILA SUZUKII INFESTATION OF FRUIT AND FRUIT WASTE
Introduction
Drosophila suzukii is a globally significant invasive pest of soft-skinned fruit crops which
spread throughout North American beginning in 2008 through 2012 (Asplen et al. 2015). During
its approximately one-month lifespan, a female D. suzukii can lay over 400 eggs, with up to 13
generations annually depending on climate conditions (Walsh et al. 2011, Kanzawa 1939). Since
its introduction to North America, D. suzukii has caused extensive damage to the small and stone
fruit industries (Tait et al. 2021). The most common management response to D. suzukii has been
aggressive pre-harvest application of pesticides, but resistance to the microbial insecticide
spinosad and pyrethroid resistance have already been found in populations of D. suzukii in
California, (Tait et al. 2021, Gress and Zalom 2019, Ganjisaffar et al. 2022). Increasing potential
for insecticide resistance necessitates an increase in non-chemical control methods.
While most other drosophilids prefer fermented fruit, D. suzukii prefer ripe fruit, likely an
ecological shift facilitated by the female D. suzukii’s enlarged serrated ovipositor which allows it
to target both immature and ripe fruit (Atallah et al. 2014). Drosophila suzukii is highly
polyphagous and it has been documented feeding on over 25 plant-families (Elsensohn and Loeb,
2018). While D. suzukii has shown preference for raspberries, blackberries, and other small fruit,
it will infest waste of fruits which it does not normally infest pre-harvest (Walsh et al. 2011,
Burrack et al. 2013, Abraham et al. 2015, Bal et al. 2017). From 2021 to 2022, 175,350 metric
tons of apple pomace and approximately 1.3 million tons of wine pomace were produced in the
United States (Jackson et al. 2022, Ferrer-Gallego and Silva, 2022). Research is ongoing for
secondary use of wine-pomace, but much post-harvest fruit waste ends up sitting near production
sites, in-field, or in landfills worldwide (Bal et al. 2017, Marcos et al. 2023, Spinei and Oroian
23



2021). This waste can be infested by D. suzukii and related species and can provide a host when
fresh fruit is no longer available (Bal et al. 2017).
Fertilizers used for other purposes in growing systems may also have applications as
control tools for D. suzukii. Nitrogen, phosphorus, and potassium are manipulated in growing
systems via granular or irrigation applications to enhance growth, crop yield, and even fruit color
(Ali et al. 2012, Vargas and Bryla 2015, Prange and DeEll 1997, Jezek et al. 2018). Calcium
based field treatments have been used to manipulate fruit firmness (Lee et al. 2016). Calcium
nitrate can be used pre-harvest and post-harvest to prevent spoilage of litchi, guava, and Indian
gooseberry (Alila and Achumi 2012, Singh and Mandal 2000, Goutam et al. 2010, Azam et al.
2021, Yadav and Singh 2002). Calcium nitrate and potassium nitrate can be used pre-harvest to
increase shelf-life of seedless barberry (Hosseini et al 2022). In lab trials, female D. suzukii laid
fewer eggs and fewer larvae survived in diets containing high concentrations of ammonia and
urea when compared to Drosophila melanogaster (Belloni et al. 2016) and adding small amounts
of high nitrogen chicken manure to apple pomace has been shown to reduce D. suzukii survival
by 80-100% in lab and small field trials (Hooper and Grieshop 2021).
These experiments were conducted to investigate applying nitrogen-based fertilizers for
D. suzukii management in fruit pre-harvest and post-harvest fruit waste. The goals of these
experiments were 1) to examine if nitrogen-based fertilizers result in similar reductions in egg
laying and larval survival as observed for high nitrogen poultry manure when incorporated into
fruit waste, and 2) to determine if nitrogen fertilizers could be used as a D. suzukii infestation
deterrent on fruit prior to harvest. If nitrogen is the main component affecting D. suzukii survival
in manure treated waste fruit, then it is expected that nitrogen-based fertilizers will limit D.
suzukii larval and egg survival in fertilizer treated fruits and fruit waste. If nitrogen fertilizers

24



disrupt D. suzukii survival, it is possible that its presence will be a deterrent to laying D. suzukii
females when applied to ripe fruit.
Materials and Methods
A colony of D. suzukii was established from flies collected at the Michigan State
University Trevor Nichols Research Center (TNRC; Fennville, MI) in 2016. Flies were reared on
corn meal diet (Dalton et al. 2011) in 300ml wide mouth glass mason jars (Ball Corporation,
Broomfield, CO). The colony was maintained in a growth chamber (Percival Scientific, Perry,
IA) set at 21˚C, 70% RH, 16:8 L:D. Flies were anesthetized using CO 2 , separated by sex on a
FlyStuff FlyPad (Genesee Scientific, San Diego, CA), and held in 50 ml polystyrene vials
(Genesee Scientific, San Diego, CA) prior to lab experiments. Following transfer to experimental
arenas, flies were monitored until moving about the arena to confirm survival.
Experiment 1- Nitrogen incorporation into fruit waste
Pomace from organically grown apples was obtained from a certified organic orchard and
cidery in Flushing, MI. Prior to experiments, apple pomace was frozen at -20ºC for a minimum
of one week prior to use to eliminate any previous arthropod infestation. Apple pomace was
thawed to room temperature prior to use in experiments. Apple pomace mixed with poultry
manure at 20% by volume in previous experiments had 1.5g N/ 250ml pomace, which is used as
the ‘100%’ value in this experiment. To assess effects of nitrogen added to infested fruit waste,
five soluble nitrogen fertilizers were each dissolved in 10ml deionized water at five different
rates: 6%,12.5%,25%,50%, or 100% by volume (Table 2.1). Based on Hooper and Grieshop
(2021), incorporation of 25% poultry manure by volume to apple pomace can reduce D. suzukii
emergence from infested waste by 95%. Fertilizer was diluted to the desired concentration in 10
ml water, and solutions were then incorporated into 250 ml apple pomace over a period of 2

25



minutes. This volume of pomace was subdivided evenly into five 50 ml replications of each
treatment. Granulated organic chicken manure (50 ml) from Herbruck’s Poultry Ranch, Inc.
(Saranac, MI) was brought to 25% moisture with distilled water before use. Experimental arenas
consisted of a 118 ml plastic deli container (Deli-Serve, Chattanooga, TN) capped by a lid with a
2 cm hole, sealed with a foam plug (“flug”, Bio-Serv, Flemington, NJ). Arenas were filled with
50 ml of apple pomace with fertilizer incorporated, manure incorporated, or left plain. Each
treatment was replicated five times. Ten, seven-day old female D. suzukii from mixed-sex colony
containers were placed in each arena for 48 h. Arenas were placed in a growth chamber set to the
same parameters used for the D. suzukii colony and checked daily for fly emergence. Emerging
flies were removed using an aspirator, enumerated, and sexed. The experiment concluded when
no D. suzukii emerged from any container for seven consecutive days.

26



Table 2.1 Fertilizer sources, analysis, and dilution in 10ml water to achieve 1.5g N (100%).
Fertilizer

Manufacturer

Nitrogen
(mg/L)
46

Phosphorus
(mg/L)
0

Potassium
(mg/L)
0

6.25%
(g)
0.20

12.5%
(g)
0.41

25%
(g)
0.82

50%
(g)
1.63

100 %
(g)
3.26

Urea

Easy Peasy Plants
(Alvin, IL)
Envy (Chicago, IL)

15.5

0

0

0.60

1.21

2.42

4.84

9.67

13

0

44

0.45

0.89

1.79

3.57

7.14

11

0

0

0.85

1.70

3.41

6.82

13.63

Ammonium
Pure Original Ingredients
21
0
Sulfate
(Lindon, UT)
Poultry
Herbruck’s Poultry Ranch,
4
3
Manure
Inc. (Saranac, MI)
*Manure is measured as 20% by volume of total media (250ml)

0

0.72

1.44

2.88

5.77

11.54

2

--

--

--

--

4.93*

Calcium
Nitrate
Potassium
Nitrate
Magnesium
Nitrate

Fireworks Cookbook LLC
(Kathleen, GA)
Greenway Biotech, Inc.
(Santa Fe Springs, CA)

27



Experiment 2- Oviposition following surface nitrogen application on whole fruit
Organically grown blueberries (North Bay Produce, Inc. Traverse City, MI) were put into
3L of deionized water and gently agitated periodically over a period of 4 hours before use to
remove pesticide or other residues and then left on paper towel to dry. To assess the effect of a
pre-harvest N application on fruit surfaces as opposed to incorporation into post-harvest waste,
blueberries were then dipped in solutions containing 1.5 g N per 150 ml from of urea, calcium
nitrate, or magnesium nitrate sources (Table 2.2) and swirled for 4 sec to ensure maximum
coating. Berries in the control treatment were swirled in plain deionized water.
Table 2.2 Fertilizer grams per solution percentage.
Fertilizer
Amount of fertilizer (g)
per 250 ml, 1.5 g N
Urea
3.26

Amount of fertilizer (g)
per 250 ml, 3.0 g N
6.52

Calcium Nitrate

9.67

19.34

Magnesium Nitrate

13.63

27.26

Ten blueberries per treatment were placed in a 15cm petri dish (VWR International LLC,
Radnor, PA), and a dish containing fruit with each treatment was placed on the floor of an
emergence cage held within a grow tent (2.7mx1.2mx2m, Vivosun, Ontario, CA) at 21˚C
70%RH, 16:8 L:D. Treatment placement was randomized in each cage to avoid position effects.
Three-day old female (100) and male (100) D. suzukii from mixed sex colony vials were placed
within a 9 cm petri dish (VWR International LLC, Radnor, PA) with dampened filter paper (No.
1, qualitative filter paper, GE Healthcare Bio-Sciences, Pittsburgh, PA) and released within the
center of the cage. This choice experiment was replicated five times. After 48 hours blueberries
were removed and dissected using a stereomicroscope to count eggs and larvae.
A second round of comparisons in which N rates for three fertilizers were doubled to 3 g
per 250 ml were conducted following initial results (Table 2.2). Blueberries were treated as in
28



the previous experiment, and treatments for choice assays were arranged in cages following the
same methods. Female (60) and male (60) 3-day old D. suzukii from mixed sex colony vials were
placed in cages using the same methods as for the prior experiment. The experiment was
replicated across five cages, which were held under the same conditions as the previous
experiment. After 48 h, blueberries were removed and stored in a fridge at 4˚C before dissection
under a stereo microscope to count eggs.
Experiment 3- Adult emergence following surface nitrogen application on whole fruit
This experiment was conducted using the same parameters and apparatus as Experiment
2 “Oviposition following surface nitrogen application on whole fruit”. Fruits were removed from
cages following 48 h of exposure to gravid female flies and placed in 473 ml deli containers
(Deli-Serve, Chattanooga, TN) with modified lids (Figure 3.1). Containers were held in a plant
growth tent (2.7mx1.2mx2m, Vivosun, Ontario, CA) at 21 ˚C 70%RH, 16:8 L:D. Adult D.
suzukii were removed and counted daily via aspiration until no flies had emerged for seven days.
Statistical Analysis
All statistical analyses were conducted using SAS version 9.4 (SAS Institute Inc., Cary,
NC, USA). Data was analyzed using a mixed model ANOVA via Proc GLIMMIX. Data from
Experiment 1 were fitted to a log distribution, and a Satterwaithe adjustment was applied to
control for unequal variances. In Experiments 2 and 3 data were fitted to a normal distribution.
For all analyses, replicate was treated as a random variable and total number of D. suzukii eggs,
larvae, or in Experiment 3 adult D. suzukii, was the response variable. Pairwise comparisons of
treatment means were made using a Tukey-Kramer adjustment with α=0.05.

29



Results
Experiment 1- Nitrogen incorporation into fruit waste
There was a significant effect of treatment (F25,100 =9.73, p<0.0001) on the number of
emerging D. suzukii. No D. suzukii emerged from treatments containing calcium nitrate,
potassium nitrate, ammonium sulfate, or poultry manure (Table 2.3). Very small numbers of D.
suzukii emerged from treatments containing magnesium nitrate which was significantly lower
than emergence in the untreated control. Urea treatments, except for the 50% rate, had similar D.
suzukii emergence to the untreated control. The highest urea concentration did not significantly
differ from the untreated control.
Table 2.3 Mean emergence of D. suzukii (±SEM) from fertilizer treatments at 6.5%,12.5%, 25%,
50%, or 100%; control; or 20% poultry manure by pomace volume. Values indicated by the
same letter are not significantly different, α=0.05.
Treatment
Mean D. suzukii ± SEM
Control

8.8 ± 2.3 a

Poultry Manure

0.0 ± 0.0 c
6.5%

12.5%

25%

50%

100%

Ammonium Sulfate

0.0 ± 0.0 c

0.0 ± 0.0 c

0.0 ± 0.0 c

0.0 ± 0.0 c

0.0 ± 0.0 c

Calcium Nitrate

0.0 ± 0.0 c

0.0 ± 0.0 c

0.0 ± 0.0 c

0.0 ± 0.0 c

0.0 ± 0.0 c

Magnesium Nitrate
Potassium Nitrate

0.2 ± 0.2 bc
0.0 ± 0.0 c

0.0 ± 0.0 c
0.0 ± 0.0 c

0.0 ± 0.0 c
0.0 ± 0.0 c

0.0 ± 0.0 c
0.0 ± 0.0 c

0.0 ± 0.0 c
0.0 ± 0.0 c

Urea

6.8 ± 5.1 ab

9.0 ± 4.2 a

8.4 ± 4.2 a

0.4 ± 0.4 bc

4.8 ± 1.2 ab

Experiment 2- Oviposition following surface nitrogen application on whole fruit
A similar number of D. suzukii eggs were laid across all treatments (Figure 2.1;
F3,9 =1.25, p= 0.3486). Doubling nitrogen rate did not change oviposition in treated fruit
compared to untreated fruit (F3,12 =0.6, p=0.625; Figure 2.2)

30



Mean D. suzukii ±SEM

250
200
150

100
50
0
Control

Calcium
Magnesium
Nitrate
Nitrate
Treatment

Urea

Figure 2.1 Mean number of D. suzukii eggs or newly hatched larvae (±SEM) per fertilizer
treatment. Values did not significantly differ, α=0.05.

Mean D. suzukii ±SEM

120
100

80
60
40
20

0
Control

Calcium
Magnesium
Nitrate
Nitrate
Treatment

Urea

Figure 2.2 Mean number of D. suzukii eggs or newly hatched larvae (±SEM) per fertilizer
treatment. Values did not significantly differ, α=0.05.

31



Experiment 3- Adult emergence following surface nitrogen application on whole fruit
Similar to observations in Experiment 2, the number of surviving adult D. suzukii did not
differ between treatments dipped in different fertilizer solutions (F 3,9 =1.58, p=0.2607; Figure

Mean D. suzukii ±SEM

2.3).

50
40

30
20
10

0
Control

Calcium
Magnesium
Nitrate
Nitrate
Treatment

Urea

Figure 2.3 Mean number of emerging D. suzukii adults (±SEM) per fertilizer treatment. Values
did not significantly differ, α=0.05.
DISCUSSION
Our laboratory experiments suggest that nitrogen containing fertilizers may be a useful
tool for controlling D. suzukii when incorporated in post-harvest waste, but that the fertilizers
evaluated do not reduce egg laying or survival of subsequent larvae when applied to whole fruit
preharvest. One of the goals of this research was to examine if nitrogen-based fertilizers result in
similar reductions in egg laying and larval survival as observed for high nitrogen poultry manure
when incorporated into fruit waste. In lab and field trials, adding at least 15% organic poultry
manure by volume reduced D. suzukii survival in post-harvest fruit waste (Hooper and Grieshop
2021, Chapter 1 this thesis). Ammonia and urea are known to be toxic to drosophilids at high
32



levels and can affect the number of eggs laid, egg viability, and overall development time of D.
suzukii (Belloni et al. 2016).
When certain nitrogen-based fertilizers (calcium nitrate, potassium nitrate, ammonium
sulfate, and magnesium nitrate) were incorporated into apple pomace, there was a notable
reduction in D. suzukii survival. However, when urea was added to apple pomace, there was no
reduction of D. suzukii compared to the control at almost all levels of nitrogen evaluated. All
fertilizers were added to pomace at rates scaled to nitrogen levels in organic poultry manure. It
was expected that if nitrogen is the main component affecting D. suzukii reduction in manure
treated waste fruit, nitrogen-based fertilizers incorporated with waste fruit should yield similar
results. Because all fertilizers were added based on similar rates of nitrogen, but results differed
between fertilizers, it can be assumed that nitrogen is not the sole component specifically causing
D. suzukii reduction within treated fruit waste.
These experiments focused on nitrogen, but other macronutrients were not investigated
and could impact management of D. suzukii. Phosphorus has been shown to strongly influence
oviposition preference which could be utilized in attract-and-kill or push-pull pest management
(Cloonan et al. 2018, Olazcuaga et al. 2019). Similarly, D. suzukii females invest adult-acquired
nitrogen, carbon, and essential amino acids to eggs and somatic tissue (O’Brien et al. 2008).
Adding excessive amounts of one macronutrient will alter the overall balance of macronutrients
within the diet (Jang and Lee 2018). Further research to investigate addition of other
macronutrients and how they might affect D. suzukii eggs, larvae, and oviposition is warranted.
This research suggests that fertilizer addition to waste impacted characteristics beyond
nitrogen-toxicity. The internal D. suzukii microbiome is dependent on its environment and
associated microbes can be harmful or beneficial (Bing et al. 2018). Yeasts are essential for D.

33



suzukii larval development and have been found to affect oviposition performance (Bellutti et al.
2018). Female D. suzukii can detect and show preference for lay materials based on volatiles,
pH, sugar content, and firmness (Olazcuaga et al. 2019, Silva-Soares et al. 2017, Kim et al.
2023). Previous research indicates that microbial volatiles may be used to repel D. suzukii from
reproductive materials or attract them in attract-and-kill scenarios (Hamby and Becher 2016,
Sato et al. 2021, Rering et al. 2023). Tracking microbial change and physical characteristics over
time was out of the scope of this research and could be investigated in future research. Similarly,
it is likely that whatever differences in characteristics, chemical makeup, or microbiome were
made by fertilizer incorporation were not replicated when fertilizers were applied to whole fruit.
A second goal of this research was to determine if nitrogen fertilizers could be used as a
D. suzukii deterrent on fruit prior to harvest. Fertilizers applied to the surface of whole fruits
application did not inhibit D. suzukii egg laying or reduce D. suzukii survival. It is likely that
whatever physiological changes take place when nitrogen fertilizers are incorporated into fruit
waste, are not replicated when fertilizers are applied to whole fruit. From this research, it can be
concluded that application of these nitrogen-based fertilizers to whole fruit does not effectively
manage D. suzukii infestation but may provide control when incorporated in post-harvest fruit
wastes. Future research investigating if other fertilizers or percentages are suitably deleterious to
D. suzukii reproduction as well as possible direct affectation to D. suzukii eggs and larvae is
supported.

34



CHAPTER 3. SURVIVAL OF DROSOPHILA SUZUKII FOLLOWING HERMETIA
ILLUCENS CO-INFESTATION
Introduction
Drosophila suzukii is an invasive fruit pest which was first reported in Michigan in 2010
(Asplen et al. 2015). In its current North American range three to nine overlapping generations
of D. suzukii develop annually, creating the potential for exponential population growth (Walsh
et al. 2011, Asplen et al. 2015). Fruit found to be infested pre- or post-harvest will be discarded
due to a strict zero-tolerance policy of insects in marketed fruit (Van Timmeren and Issacs 2013).
Intense and repetitive use of insecticides used for pre-harvest management of D. suzukii creates
not only an environmental concern but also a concern of increased insecticide resistance (Van
Timmeren and Issacs 2013, Fanning et al. 2018, Shaw et al. 2019, Jones 2020). Populations of D.
suzukii showing resistance to commonly used pyrethroid insecticides and the only organically
acceptable active ingredient against D. suzukii, spinosyn, have already been found in California
(Gress and Zalom 2019, Ganjisaffar et al. 2022). Like many drosophila species, D. suzukii will
oviposit in decomposing fruit late in the growing season, including fruits with tougher skin and
tissue as they breakdown, as well as processing and post-harvest fruit waste (Bal et al. 2017).
In addition to rendering fruit unmarketable, D. suzukii infestation can also cause loss
from secondary infections of bacterial and fungal pathogens (Molina et al. 1974, Louis et
al.1996). Aside from fruit discarded due to insect infestation, fruit waste may also include
damaged or overripe fruit discarded during processing and pomace left over from cider, juice,
and wine production (Dhillon et al. 2013, Maicas and Mateo 2020, Buzby et al. 2014). Culled
fruit and fruit waste provide resources for multiple Drosophila species which can lead to further
infestation if left in and around orchards and contamination in processing areas (Bal et al 2017,
Leach et al 2018). Fruit waste management may consist of piling in unused fields, composting,
35



feeding animals, and landfilling (Esparza et al. 2020). Postharvest sanitation can be implemented
to prevent further D. suzukii infestation of fruit wastes. Solarization of infested fruit in plastic
bags is an option, but this is not feasible for the large quantities of waste typical in packing or
processing operations (Haye et al. 2016, Leach et al 2018). Burial can effectively reduce
emergence (Hooper and Grieshop 2020) but requires waste to be buried at least 24 cm which is
also impractical for large quantities of fruit. Composting and crushing have been investigated
with some success but would require extensive labor which may be costly for small operations
with large amounts of fruit (Hooper and Grieshop 2021, N. Rothwell personal communication,
Chapter 1 this thesis).
Current biocontrol agents for D. suzukii consists of a few North American Pteromalidae,
and Diapriidae wasp species which parasitize pupae, generalist predators, and a few introduced
Asian-native Braconidae and Figitidae wasp species (Lee et al. 2019, Beers et al. 2022, Wang et
al. 2020). North American wasp parasitoids have been difficult to rear on D. suzukii and do not
effectively target D. suzukii in situ (Lee et al. 2019, Huang et al. 2023). Generalist predators such
as rove beetles, ants, spiders, and earwigs will remove pupated larvae in the orchard floor, but
are unlikely to affect the eggs, larvae, and adult D. suzukii which infest fruits in the canopy
(Woltz and Lee 2017, Gabarra et al 2015, Lee et. al 2019). Asian-native wasps are more specific
D. suzukii parasitoids but are not currently commercially available within the United States and
establishing rearing colonies is time consuming and would likely be cost prohibitive for smaller
fruit producers (Seehausen et al. 2022, Fellin et al. 2023).
Hermetia illucens (Linnaeus) (Diptera: Stratiomyidae) is a wasp mimic with worldwide
distribution and is active in the southeastern United States (Marshall et al. 2015). Like many
soldier flies, H. illucens is often associated with decomposing substrates and eggs are typically

36



deposited above or adjacent to decaying matter including fruit, carrion, and manure (James 1935,
Tingle et al. 1975, Sheppard et al. 2002). Larvae feed for about two weeks and then become
prepupae which can be collected as they leave food materials prior to pupation (Craig Sheppard
et al. 1994, Tomberlin et al. 2002, Holmes et al. 2013). Hermetia illucens larvae have been used
to compost wastes and are considered to be an under-utilized method of waste sanitation
(Čičková et al. 2015, Horgan et al. 2023).
Hermetia illucens emerge as adults after about two weeks (Tomberlin et al. 2002). Adults
do not bite, sting, or spread diseases (Oliveira et al. 2016). Hermetia illucens larvae are able to
decompose food waste effectively because of their strong mouthparts and high gut enzymatic
activity and have been shown to degrade antibiotics and pesticides during bioconversion (Kim et
al. 2011, Tomberlin et al. 2002, Lalander et al. 2016). Hermetia illucens are already commonly
used for household composting as the rearing process can be replicated inexpensively from home
to commercial scale (Devic and Maquart 2015, Craig Sheppard et al. 1994;2002, Diener et al.
2011, Rayar et al. 2020). Hermetia illucens have been reared on poultry manure, swine manure,
dairy manure, vegetable wastes, and food wastes (Newton et al. 2005, Rehman et al. 2017, Parra
Paz et al. 2015, Salomone et al. 2016). Aside from waste management, H. illucens presence in
media has been shown to limit Musca domestica (Linnaeus) (Diptera: Muscidae) reproduction
(Sheppard 1983, Furman et al. 1959, Bradley and Sheppard 1984).
We set out to test if H. illucens could be used to limit or prevent D. suzukii infestation in
waste fruit which would present a mode of cultural control that would be more accessible and
cost effective than other current sanitation methods. Area-wide management of D. suzukii on
post-harvest fruit wastes could reduce the total pest population within crop and non-crop areas
(Haye et al. 2016). Managing D. suzukii infested fruit waste by adding H. illucens larvae would

37



not require the addition of insecticides, and therefore may be beneficial to organic growers who
have more limited pest control options. To assess the potential of H. illucens larvae to reduce D.
suzukii development in post-harvest fruit waste, we compared a range of infestation scenarios
with the expectation that the addition of H. illucens larvae to D. suzukii infested pomace would
reduce emergence of D. suzukii adults.
Materials and Methods
Drosophila suzukii used in experiments were obtained from a laboratory colony sourced
from the Trevor Nichols Research Center (TNRC) at Michigan State University (Fennville, MI)
in 2016 and maintained on a cornmeal-based diet (Dalton et al. 2011) in 50 ml polystyrene vials
(Genesee Scientific, San Diego, CA). Drosophila suzukii were reared in a growth chamber set at
22˚C, 70% relative humidity (RH), and a photoperiod of 16:8 h (L:D).
For experiments 1, 2, and 3 H. illucens were sourced from EVO Conversion Systems,
LLC (College station, TX). For experiment 4, H. illucens were purchased from
DubiaRoaches.com, LLC (Wichita, KS).Apple pomace was collected from a certified organic
apple orchard and cidery in Flushing, MI and frozen at -20ºC for a minimum of 48 h prior to kill
any arthropods present at the time of collection. Apple pomace was placed within a mesh cage to
prevent infestation and brought to room temperature before use.
Experimental arenas used in Experiments 1, 2, and 3 consisted of a 473 ml plastic deli
container (Deli-Serve, Chattanooga, TN) with a 23-gauge galvanized steel hardware cloth
(Everbilt, Wilmington, DE) bottom to allow for drainage held within a 946 ml plastic deli
container (Deli-Serve, Chattanooga, TN). A No. 1 qualitative filter paper (GE Healthcare BioSciences, Pittsburgh, PA) was placed on top of the hardware cloth to keep adult D. suzukii within
the upper portion of the arenas. Arenas were then capped by a lid that had two 2 cm holes. One

38



hole was covered with 150-micron polyester mesh (The Cary Company, Addison, IL) to allow
for ventilation, and the other hole was covered with Parafilm (Bemis Company, Inc., Neenah,
WI) to allow for the insertion of an aspirator hose (Figure 3.1).

Figure 3.1 Experimental arena consisting of a 473 ml plastic deli container with a wire-mesh
bottom set within a 946 ml plastic deli container. The smaller cup is lined with a piece of filter
paper, on top of which fruit waste was placed. Arenas were capped by a lid with two 2 cm holes,
one covered in fine mesh and the other covered by Parafilm.
Experiment 1- D. suzukii establishment in H. illucens infested substrates
Five infestation timing treatments were compared: simultaneous D. suzukii and H.
illucens infestation, D. suzukii infestation 3 d after H. illucens infestation, D. suzukii infestation 7
d after H. illucens infestation, and D. suzukii alone. Each infestation timing was compared in
both 250 ml (170g) organic apple pomace, or 90% organic apple pomace mixed with 10%
organic poultry manure (Herbruck's Poultry Ranch, Inc., Saranac, MI, USA) by volume for a
total of ten treatments. Treatments were replicated three times.
For treatments containing H. illucens, 3 g of approximately 12-day old (second instar)
larvae were added to experimental arenas, and for D. suzukii containing treatments, ten sevenday-old presumed mated female flies from mixed sex colony vials were added to arenas. Arenas
were held in a growth chamber (Percival Scientific, Perry, IA) at 22˚C, 70% RH, 16:8 L:D, and

39



checked daily for D. suzukii emergence. Adult D. suzukii were aspirated daily and recorded until
no emergence took place for seven days.
Experiment 2- Staggered H. illucens infestation of D. suzukii infested fruit waste
Drosophila suzukii infested apple pomace was generated by placing ten seven-day-old
presumed mated females from mixed sex colony vials in cages with the substrate for 48 h, after
which all adult D. suzukii were removed. Three different H. illucens infestation timing treatments
were applied to 250 ml of D. suzukii infested pomace (Figure 3.2). Three grams of approximately
15- day old (second instar) H. illucens larvae (five insects) were added on the same day as D.
suzukii infestation, three days after D. suzukii infestation, or seven days after D. suzukii
infestation. Two controls consisting of just H. illucens or just D. suzukii added on the first day of
the experiment were also compared for a total of five treatments. All treatments were replicated
five times. Treatments were randomly arranged on trays and held within a growth chamber with
controls set to 22˚C, 70% relative humidity (RH), and a photoperiod of 16:8 h (L:D). Arenas
were checked daily and emerged D. suzukii were removed via aspiration daily and recorded, until
seven days had passed since the last emergence. In instances where D. suzukii pupated outside of
experimental arenas, pupae were removed to vials and kept standard to colony rearing methods
and monitored for survival. Surviving D. suzukii were counted with those removed from arenas.
Experiment 3- Combination of D. suzukii infested fruit waste and H. illucens infested fruit waste
In order to determine if the presence of H. illucens larvae repel D. suzukii females, if
larvae predate D. suzukii eggs and larvae, or both, this experiment combined D. suzukii infested
pomace with pomace containing H. illucens larvae, pomace containing D. suzukii eggs and
larvae, or plain pomace. Organic apple pomace was infested with adult D. suzukii for 48 hrs. D.
suzukii adults were then removed. Infested pomace (250 ml) was added to an additional 250 ml

40



of: (1) D. suzukii infested pomace, (2) pomace containing no insects, or (3) pomace infested with
3g of approximately 12-day old (second instar) H. illucens larvae (Figure 3.2). Arenas were
checked daily until seven days past the last D. suzukii eclosion. Emerging D. suzukii were
removed via aspiration and counted.

Figure 3.2 Apple pomace was infested with either D. suzukii (SWD) or H. illucens (BSF). SWD
infested pomace was then mixed with either more SWD infested pomace, plain apple pomace, or
BSF infested pomace.
Experiment 4- H. illucens infestation rate
This experiment was conducted to compare D. suzukii egg and larvae survival when
exposed to different rates of H. illucens infestation. To do this, we provisioned three different
volumes of pomace, 170g (250ml), 340g (500ml), 680g (750ml), into 946 ml plastic deli
containers (Deli-Serve, Chattanooga, TN) and then infested with 15, 30, or 45 pre-mated female
D. suzukii respectively for 48 h. Each container was capped with a corresponding lid with two 2
cm holes, one hole covered with 150-micron polyester mesh (The Cary Company, Addison, IL)
to allow for ventilation, and one hole covered with Parafilm (Bemis Company, Inc., Neenah, WI)
to allow for aspirator insertion.
Five approximately 8-day old H. illucens larvae were added to each experimental arena.
Positive controls consisted of each volume of pomace infested with only D. suzukii. Negative
controls consisted of each volume of pomace with only 5 H. illucens added, for a total of nine
41



treatments. Treatments were replicated four times, and there were thirty-six experimental arenas
in total. Arenas were placed in a grow tent (2.7mx1.2mx2m Vivosun, Ontario, CA) at 21̊C, 70
RH with a photoperiod of 16:8 L:D for a period of three weeks. Following the start of D. suzukii
emergence, all treatments were checked every other day, and D. suzukii were collected via
aspiration every two days, frozen, sexed, and counted. The experiment concluded when all H.
illucens larvae had pupated. Hermetia illucens pupae were then removed from all arenas and
held to assess survival.
Statistical Analysis
All statistical analyses were conducted using SAS version 9.4 (SAS Institute Inc., Cary,
NC, USA). In all experiments, a general linear mixed model ANOVA was fitted to a logistic
distribution via Proc GLIMMIX. The response variable was emergent D. suzukii and replicate
was included in models as a random effect. In experiment 2 a Satterwaithe adjustment was
applied to control unequal variances. In experiment 4 pomace volume and H. illucens infestation
were considered fixed effects. In experiment 1, where significant effects were observed,
nonparametric test of treatment effects were conducted via Proc NPAR1WAY using the KruskalWallis test. In experiments 2-4, pairwise mean comparisons were conducted using the TukeyKramer adjustment with α=0.05 when significant effects were observed.
Results
Experiment 1- D. suzukii establishment in H. illucens infested substrates
Treatments were significantly different (X2 = 22.8, p = 0.0018, df = 7; data not shown),
with D. suzukii emerging only from the control treatment which did not contain H. illucens.
Experiment 2- Staggered H. illucens infestation of D. suzukii infested fruit waste

42



There were significant differences between treatments (F2,12 = 45.14, p = < 0.0001). No
D. suzukii adults emerged in treatments where H. illucens larvae were infested simultaneously
with D. suzukii (Figure 3.3). When H. illucens were added day 7, 4 times more D. suzukii (39.4
± 11.3) emerged than when H. illucens were added day 3 (9.8 ± 2.0). In treatments where H.
illucens were added on day 3, D. suzukii were observed to pupate on the lids of arenas. Of the

Mean D. suzukii ±SEM

total 29 D. suzukii pupae collected from lids across all treatments, 5 survived to adulthood.

60
50
40
30
20
10
0

a

b

c
H. illucens add
day 0

H. illucens add
day 3
Treatment

H. illucens add
day 7

Figure 3.3 Mean D. suzukii (±SEM) collected in Experiment 2- Staggered H. illucens infestation
of D. suzukii infested fruit waste. Letters denote a significant difference between α=0.05.
Experiment 3- Combination of D. suzukii infested fruit waste and H. illucens infested fruit waste
When D. suzukii infested pomace was added to plain pomace, more D. suzukii reached
adulthood per replicate (96 ± 14.4) than when D. suzukii infested pomace was added to H.
illucens infested pomace (31 ± 3.6) per replicate (F 2,8 =37.25, p<0.0001). Hermetia illucens
infestation reduced D. suzukii emergence as compared to emergence from D. suzukii infested

43



pomace added to either infested or plain pomace. Treatments with no H. illucens larvae did not
have significantly different numbers of D. suzukii emerge (Figure 3.4).

Mean D. suzukii ±SEM

120

a

100

80
60

a

40
20
0

b
D. suzukii + H.
illucens

D. suzukii +
pomace
Treatment

D. suzukii + D.
suzukii

Figure 3.4 Mean emergence D. suzukii (±SEM) from each treatment where D. suzukii infested
pomace was added to plain pomace, more D. suzukii infested pomace, or H. illucens infested
pomace. Letters denote a significant difference between α=0.05.
Experiment 4- H. illucens infestation rate
In contrast with previous experiments, H. illucens infestation did not significantly reduce
D. suzukii emergence regardless of volume of pomace in this experiment. More D. suzukii
emerged as pomace volume increased (F 2,17 =6.29, p=0.009). Treatments with 250 ml pomace
had an average of 222 ± 42.5 adult D. suzukii emerge per replicate, 500 ml had an average of 335
± 42.5 D. suzukii, and 750ml had an average of 435 ± 42.5 D. suzukii per replicate. The lowest
volume of pomace (250ml) had significantly less D. suzukii than the highest volume of pomace
(750ml).
Discussion
Here I show that adding black soldier fly larvae to apple pomace can reduce infestation
by D. suzukii. However, the effectiveness of this method at controlling D. suzukii numbers
44



depends on the timing of black soldier fly addition relative to D. suzukii infestation. When D.
suzukii adults were added to infest substrate containing H. illucens larvae, D. suzukii offspring
only survived to adulthood in control treatments where no H. illucens larvae were present. When
D. suzukii were allowed to infest apple pomace for different time periods before H. illucens
larvae addition, D. suzukii only emerged in treatments where H. illucens larvae were added
following D. suzukii infestation. In laboratory settings, D. suzukii larvae will exit their diet to
pupate and in field settings they are known to leave fruit to pupate in the soil to avoid
intraspecific competition (Da Silva et al. 2019, Woltz and Lee 2017). When H. illucens larvae
were added three days after D. suzukii infested pomace, D. suzukii larvae were observed
crowding and pupating on arena lids (Figure 3.1). This atypical pupation behavior has never been
observed in research utilizing this experimental design
Competition with closely related insects has been observed to affect D. suzukii behavior
and performance. In laboratory trials, the presence of other Drosophila species in a substrate
significantly reduced D. suzukii emergence and egg laying (Shaw et al. 2017). Intraspecific
competition has been observed in tephritid flies (Averill and Prokopy, 1987; Nufio & Papaj,
2001) and D. suzukii females may similarly experience increased pressure to select uninfested
hosts (Bezerra Da Silva et al. 2019). While other studies reference H. illucens larvae repelling
other dipterans, there is little information about the mechanisms behind this behavior. Hermetia
illucens are known to condition material with their own gut microflora, which might be a source
of a deterrent or chemiosignal (Yu et al. 2011). Bradley and Shepard (1984) suggested that H.
illucens larvae have an allomone which repels other dipterans from lay material. Further research
should be completed to determine what signals H. illucens infestation creates, if any, to dissuade

45



D. suzukii females, which may further be exploited for oviposition deterrence and infestation
management (Mitsui et al. 2006, Shaw et al. 2017, Tait et al. 2021).
When we added H. illucens larvae to substrate previously infested with D. suzukii, D.
suzukii did not survive to adulthood. It is likely that H. illucens addition resulted in larval death,
perhaps through predation, injury, or by rendering the substrate no longer a suitable food source.
Current insects examined for biocontrol of D. suzukii rely heavily on parasitism or predation of
larvae and pupae in preharvest fruit. As such, those biological control agents may also be
exposed to pesticides or other management practices for D. suzukii. Incorporating H. illucens in
post-harvest fruit waste sanitation provides a scenario in which the biocontrol insects are less
likely to be exposed to pesticides used against D. suzukii (Lee et al. 2019, Tait et al. 2021). The
information from these experiments presents another avenue for improved biocontrol using
native species against invasive pests.
When H. illucens were added to different rates of D. suzukii infested pomace, there was
no significant difference between treatments. This contrasted with our results from Experiments
1-3 where addition of H. illucens larvae were always shown to limit D. suzukii reproduction in
apple pomace. The treatment which most successfully curtailed D. suzukii infestation was that in
which H. illucens larvae were added shortly after D. suzukii infestation. It is possible that in our
final experiment, there was no difference found between addition rates of H. illucens because D.
suzukii had already had substantial time to infest the pomace and so were not affected by any
microbial or volatile shifts due to H. illucens. More research is necessary to investigate optimal
timing and density of H. illucens infestation as a post-harvest biological control agent.
Although all H. illucens larvae in all experiments were of a similar instar based on age in
days, those used in our last experiment were observed to be smaller in mass and body size than

46



those used in previous experiments which might have been the cause for resulting discrepancies.
Although both sources of insects were reared on a mass rearing diet with similar ingredients,
these diets were not identical. It has been suggested that differences in growth rates and
bioconversion efficiency of later larval stages can be due time spent on substrate (Horgan et al.
2023, Sheppard et al. 2002).
Post harvest fruit waste infestation with H. illucens may provide additional benefits
beyond pest control. Hermetia illucens have been documented to reduce Salmonella spp,
Escherichia coli O157:H7, antibiotics, and pesticides during bioconversion, and the resulting
larvae may be utilized as livestock and other animal food (Erickson et al. 2004, Lalander et al.
2016). Hermetia illucens could be utilized in many different D. suzukii management systems as
H. illucens larvae are more cost effective than other biocontrol insects currently available,
process multiple waste streams willingly, and do not require the addition of any pesticides or
materials restricted in organic production (Lee et. al 2019, Tait et al. 2021). Hermetia illucens
larvae are readily available in the United States via native wild populations and commercial
rearing operations. The addition of H. illucens to process fruit waste might also be more costeffective when compared to cost of materials and/or labor required for solarization, burial, or
composting with animal manures (Leach et al 2018, Hooper and Grieshop 2020;2021). Overall,
this research supports that H. illucens larvae addition can impact the D. suzukii infestation
process and has the potential to be an inexpensive and accessible addition to management of fruit
waste infested with or at risk of infestation by D. suzukii.

47



LITERATURE CITED
Abraham, J., Zhang, A., Angeli, S., Abubeker, S., Michel, C., Feng, Y., Rodriguez-Saona, C.,
2015. Behavioral and Antennal Responses of Drosophila suzukii (Diptera: Drosophilidae)
to Volatiles from Fruit Extracts. Environmental Entomology 44, 356–367.
Ali, L., Alsanius, B.W., Rosberg, A.K., Svensson, B., Nielsen, T., Olsson, M.E., 2012. Effects of
nutrition strategy on the levels of nutrients and bioactive compounds in blackberries. Eur
Food Res Technol 234, 33–44.
Alila, P., Achumi, I., 2012. Pre-Harvest Chemical Treatments Affect Post-Harvest Quality of
Litchi Fruit. Acta Hortic. 755–761.
Asplen, M.K., Anfora, G., Biondi, A., Choi, D.-S., Chu, D., Daane, K.M., Gibert, P., Gutierrez,
A.P., Hoelmer, K.A., Hutchison, W.D., Isaacs, R., Jiang, Z.-L., Kárpáti, Z., Kimura, M.T.,
Pascual, M., Philips, C.R., Plantamp, C., Ponti, L., Vétek, G., Vogt, H., Walton, V.M., Yu,
Y., Zappalà, L., Desneux, N., 2015. Invasion biology of spotted wing Drosophila
(Drosophila suzukii): a global perspective and future priorities. J. Pest Sci 88, 469–494.
Atallah, J., Teixeira, L., Salazar, R., Zaragoza, G., Kopp, A., 2014. The making of a pest: the
evolution of a fruit-penetrating ovipositor in Drosophila suzukii and related species.
Proceedings of the Royal Society B: Biological Sciences 281, 20132840.
Averill, A.L., Prokopy, R.J., 1987. Intraspecific Competition in the Tephritid Fruit Fly
Rhagoletis Pomonella. Ecology 68, 878–886.
Azam, M., Ilahy, R., Shen, J., Qadri, R., Iqbal, M.A., Yasmin, Z., Haider, S.-T.-A., Khan, M.A.,
Jaskani, M.J., Malik, A.U., Hussain, S., 2021. Exogenous calcium nitrate application delays
senescence, enhance nutraceutical properties and antioxidant defense system during storage.
Emirates Journal of Food and Agriculture 33(10):852-862.
Bal, H.K., Adams, C., Grieshop, M., 2017. Evaluation of Off-season Potential Breeding Sources
for Spotted Wing Drosophila (Drosophila suzukii Matsumura) in Michigan. J. Econ.
Entomology 110, 2466–2470.
Ballman, E.S., Collins, J.A., Drummond, F.A., 2017. Pupation Behavior and Predation on
Drosophila suzukii (Diptera: Drosophilidae) Pupae in Maine Wild Blueberry Fields. J.
Econ. Entomology 110, 2308–2317.
Ballman, E.S., Drummond, F.A., 2017. Infestation of Wild Fruit by Drosophila suzukii
Surrounding Maine Wild Blueberry Fields1. JAUE 33, 61–70.
Band, H.,1993. Drosophilidae (Diptera) Collected in Spring in Michigan. The Great Lakes
Entomologist 26 (3).

48



Beers, E.H., Beal, D., Smytheman, P., Abram, P.K., Schmidt-Jeffris, R., Moretti, E., Daane,
K.M., Looney, C., Lue, C.-H., Buffington, M., 2022. First records of adventive populations
of the parasitoids Ganaspis brasiliensis and Leptopilina japonica in the United States. J.
Hymenoptera Research 91, 11–25.
Belloni, V., Galeazzi, A., Bernini, G., Mandrioli, M., Versace, E., Haase, A., 2018. Evolutionary
compromises to metabolic toxins: Ammonia and urea tolerance in Drosophila suzukii and
Drosophila melanogaster. Physiology & Behavior 191, 146–154.
Bellutti, N., Gallmetzer, A., Innerebner, G., Schmidt, S., Zelger, R., Koschier, E.H., 2018.
Dietary yeast affects preference and performance in Drosophila suzukii. J. Pest Sci 91, 651–
660.
Bezerra Da Silva, C.S., Park, K.R., Blood, R.A., Walton,V.M.,2019. Intraspecific Competition
Affects the Pupation Behavior of Spotted-Wing Drosophila (Drosophila Suzukii). Scientific
Reports 9 (1):7775.
Bing, X., Gerlach, J., Loeb, G., Buchon, N., 2018. Nutrient-Dependent Impact of Microbes on
Drosophila suzukii Development. mBio 9 (2).
Bolda, M.P., Goodhue, R.E., Zalom, F.G., 2010. Spotted Wing Drosophila: Potential Economic
Impact of a Newly Established Pest. Giannini Foundation of Agricultural Economics 4.
Bradley, S.W., Sheppard, D.C., 1984. House fly oviposition inhibition by larvae of Hermetia
illucens, the black soldier fly. J. Chem Ecol 10, 853–859.
Brown, S.K., Way, R.D., Terry, D.E.,1989. Sweet and Tart Cherry Varieties: Descriptions and
Cultural Recommendations. New York Food and Life Sciences 127.
Burrack, H.J., Fernandez, G.E., Spivey, T., Kraus, D.A., 2013. Variation in selection and
utilization of host crops in the field and laboratory by Drosophila suzukii Matsumara
(Diptera: Drosophilidae), an invasive frugivore. Pest Management Science 69, 1173–1180.
Buzby, J.C., Farah-Wells, H., Hyman, J., 2014. The Estimated Amount, Value, and Calories of
Postharvest Food Losses at the Retail and Consumer Levels in the United States. USDAERS SSRN Journal 121.
Čičková, H., Newton, G.L., Lacy, R.C., Kozánek, M., 2015. The use of fly larvae for organic
waste treatment. Waste Management 35, 68–80.
Cloonan, K.R., Abraham, J., Angeli, S., Syed, Z., Rodriguez-Saona, C., 2018. Advances in the
Chemical Ecology of the Spotted Wing Drosophila (Drosophila suzukii) and its
Applications. J. Chem Ecol 44, 922–939.

49



Craig Sheppard, D., Larry Newton, G., Thompson, S.A., Savage, S., 1994. A value added
manure management system using the black soldier fly. Bioresource Technology 50, 275–
279.
Dhillon, G.S., Kaur, S., Brar, S.K., 2013. Perspective of apple processing wastes as low-cost
substrates for bioproduction of high value products: A review. Renewable and Sustainable
Energy Reviews 27, 789–805.
Diener, S., Zurbrügg, C., Tockner, K., 2009. Conversion of organic material by black soldier fly
larvae: establishing optimal feeding rates. Waste Manag Res 27, 603–610.
Elsensohn, J.E., Loeb, G.M., 2018. Non-Crop Host Sampling Yields Insights into Small-Scale
Population Dynamics of Drosophila suzukii (Matsumura). Insects 9, 5.
Emekci, M., Moore, D., 2015. Sap Beetles, in: Wakil, W., Romeno Faleiro, J., Miller, T.A.
(Eds.), Sustainable Pest Management in Date Palm: Current Status and Emerging
Challenges, Sustainability in Plant and Crop Protection. Springer International Publishing,
Cham, pp. 205–235.
Erickson, M.C., Islam, M., Sheppard, C., Liao, J., Doyle, M.P., 2004. Reduction of Escherichia
coli O157:H7 and Salmonella enterica Serovar Enteritidis in Chicken Manure by Larvae of
the Black Soldier Fly. Journal of Food Protection 67, 685–690.
Esparza, I., Jiménez-Moreno, N., Bimbela, F., Ancín-Azpilicueta, C., Gandía, L.M., 2020. Fruit
and vegetable waste management: Conventional and emerging approaches. Journal of
Environmental Management 265, 110510.
Fanning, P.D., Grieshop, M.J., Isaacs, R., 2018. Efficacy of biopesticides on spotted wing
drosophila, Drosophila suzukii Matsumura in fall red raspberries. Journal of Applied
Entomology 142, 26–32.
Fellin, L., Grassi, A., Puppato, S., Saddi, A., Anfora, G., Ioriatti, C., Rossi-Stacconi, M.V., 2023.
First report on classical biological control releases of the larval parasitoid Ganaspis
brasiliensis against Drosophila suzukii in northern Italy. BioControl 68, 1–12.
Ferrer-Gallego, R., Silva, P., 2022. The Wine Industry By-Products: Applications for Food
Industry and Health Benefits. Antioxidants 11, 2025.
Furman, D.P., Young, R.D., Catts, Paul.E., 1959. Hermetia illucens (Linnaeus) as a Factor in the
Natural Control of Musca domestica Linnaeus. J. Econ. Entomology 52, 917–921.
Gabarra, R., Riudavets, J., Rodríguez, G.A., Pujade-Villar, J., Arnó, J., 2015. Prospects for the
biological control of Drosophila suzukii. BioControl 60, 331–339.

50



Ganjisaffar, F., Demkovich, M.R., Chiu, J.C., Zalom, F.G., 2022. Characterization of Field Derived Drosophila suzukii (Diptera: Drosophilidae) Resistance to Pyrethroids in California
Berry Production. J. Econ. Entomology 115, 1676–1684.
Goutam, M., Dhaliwal, H.S., Mahajan, B.V.C., 2010. Effect of pre-harvest calcium sprays on
post-harvest life of winter guava (Psidium guajava L.). J. Food Sci Technol 47, 501–506.
Gress, B.E., Zalom, F.G., 2019. Identification and risk assessment of spinosad resistance in a
California population of Drosophila suzukii. Pest Management Science 75, 1270–1276.
Hamby, K.A., Becher, P.G., 2016. Current knowledge of interactions between Drosophila
suzukii and microbes, and their potential utility for pest management. J. Pest Sci 89, 621–
630.
Haye, T., Girod, P., Cuthbertson, A.G.S., Wang, X.G., Daane, K.M., Hoelmer, K.A., Baroffio,
C., Zhang, J.P., Desneux, N., 2016. Current SWD IPM tactics and their practical
implementation in fruit crops across different regions around the world. J. Pest Sci 89, 643–
651.
Hennig, E.I., Mazzi, D., 2018. Spotted Wing Drosophila in Sweet Cherry Orchards in Relation to
Forest Characteristics, Bycatch, and Resource Availability. Insects 9, 118.
Higbee, B., and J. Siegel. 2009. New Navel Orangeworm Sanitation Standards Could Reduce
Almond Damage. California Agriculture 63 (1): 24–28.
Holmes, L.A., Vanlaerhoven, S.L., Tomberlin, J.K., 2013. Substrate Effects on Pupation and
Adult Emergence of Hermetia illucens (Diptera: Stratiomyidae). Environmental
Entomology 42, 370–374.
Hooper, H., Grieshop, M.J., 2021. Composting susceptible fruit wastes reduces Drosophila
suzukii (Diptera: Drosophilidae) reproductive habitat. Pest Management Science 77, 202–
207.
Hooper, H., Grieshop, M.J., 2020. Postharvest Burial of Drosophila suzukii (Diptera:
Drosophilidae) Infested Fruit Waste Reduces Adult Emergence. Environmental Entomology
49, 59–65.
Horgan, F.G., Launders, M., Mundaca, E.A., Crisol-Martínez, E., 2023. Effects of Intraspecific
Competition and Larval Size on Bioconversion of Apple Pomace Inoculated with Black
Soldier Fly. Agriculture 13, 452.
Hosseini, A., Moradinezhad, F., Khayyat, M., Aminifard, M., 2022. Bioactive Compounds and
Quality Attributes of Fresh Seedless Barberry (Berberis vulgaris L.) at Cold Storage as
Influenced by Multiple Spraying of Calcium Nitrate and Potassium Nitrate. Journal of
Agricultural Sciences – Sri Lanka 17, 258.

51



Huang, J., Gut, L., Grieshop, M., 2017. Evaluation of Food-Based Attractants for Drosophila
suzukii (Diptera: Drosophilidae). Environmental Entomology 46, 878–884.
Huang, J., Leach, H., Buffington, M., Rothwell, N., Wilson, J.K., 2023. Resident parasitoids
associated with Drosophilidae in Michigan tart cherry orchards and woodland edges.
Journal of Hymenoptera Research 96, 485–494.
Hubhachen, Z., Pointon, H., Perkins, J.A., Van Timmeren, S., Pittendrigh,B., Isaacs, R., 2022.
Resistance to Multiple Insecticide Classes in the Vinegar Fly Drosophila Melanogaster
(Diptera: Drosophilidae) in Michigan Vineyards.” J. Econ. Entomology 115(6): 2020–28.
Hulthen, A.D., Clarke, A.R., 2006. The Influence of Soil Type and Moisture on Pupal Survival
of Bactrocera Tryoni (Froggatt) (Diptera: Tephritidae). Australian Journal of Entomology
45 (1): 16–19.
Jackson, C., Shukla, V., Kolba, N., Agarwal, N., Padilla-Zakour, O.I., Tako, E., 2022. Empire
Apple (Malus domestica) Juice, Pomace, and Pulp Modulate Intestinal Functionality,
Morphology, and Bacterial Populations In Vivo (Gallus gallus). Nutrients 14, 4955.
Jang, T., Lee, K.P., 2018. Comparing the impacts of macronutrients on life-history traits in larval
and adult Drosophila melanogaster: the use of nutritional geometry and chemically defined
diets. Journal of Experimental Biology 221, jeb181115.
Jezek, M., Zörb, C., Merkt, N., Geilfus, C.-M., 2018. Anthocyanin Management in Fruits by
Fertilization. J. Agric. Food Chem. 66, 753–764.
Joshi, N. K., Demchak, K., Biddinger,D., 2023. Seasonal Population of Drosophila Suzukii
(Diptera: Drosophilidae) and Pesticide Use Pattern after Its Invasion in Caneberry Crops in
Pennsylvania (USA). Arthropoda 1 (1): 25–34.
Kanzawa, T., 1939. Studies on Drosophila suzukii Mats. Studies on Drosophila suzukii Mats.
pp.49
Kienzle, R., Groß, L.B., Caughman, S., Rohlfs, M., 2020. Resource Use by Individual
Drosophila Suzukii Reveals a Flexible Preference for Oviposition into Healthy Fruits.
Scientific Reports 10 (1): 3132.
Kim, H., Kim, Y., Roh, G.H., Kim, Y.H., 2023. Comparison of Preference for Chemicals
Associated with Fruit Fermentation between Drosophila melanogaster and Drosophila
suzukii and between Virgin and Mated D. melanogaster. Insects 14, 382.
Kim, W., Bae, S., Park, K., Lee, S., Choi, Y., Han, S., Koh, Y., 2011. Biochemical
characterization of digestive enzymes in the black soldier fly, Hermetia illucens (Diptera:
Stratiomyidae). Journal of Asia-Pacific Entomology 14, 11–14.

52



Kirkpatrick, D., Gut, L., Miller, J., 2018. Estimating Monitoring Trap Plume Reach and
Trapping Area for Drosophila suzukii (Diptera: Drosophilidae) in Michigan Tart Cherry, J.
Econ. Entomology, 111, 1285–1289.
Lalander, C., Senecal, J., Gros Calvo, M., Ahrens, L., Josefsson, S., Wiberg, K., Vinnerås, B.,
2016. Fate of pharmaceuticals and pesticides in fly larvae composting. Science of The Total
Environment 565, 279–286.
Leach, H., Moses, J., Hanson, E., Fanning, P., Isaacs, R., 2018. Rapid harvest schedules and fruit
removal as non-chemical approaches for managing spotted wing Drosophila. J. Pest Sci 91,
219–226.
Lee, J. C., D. J. Bruck, A. J. Dreves, C. Ioriatti, H. Vogt, and P. Baufeld. 2011. In Focus: spotted
wing drosophila, Drosophila suzukii, across perspectives. Pest Manag. Sci. 67: 1349–1351
Lee, J.C., Dalton, D.T., Swoboda-Bhattarai, K.A., Bruck, D.J., Burrack, H.J., Strik, B.C., Woltz,
J.M., Walton, V.M., 2016. Characterization and manipulation of fruit susceptibility to
Drosophila suzukii. J. Pest Sci 89, 771–780.
Lee, J.C., Dreves, A.J., Cave, A.M., Kawai, S., Isaacs, R., Miller, J.C., Van Timmeren, S.,
Bruck, D.J., 2015. Infestation of Wild and Ornamental Noncrop Fruits by Drosophila
suzukii (Diptera: Drosophilidae). Annals of the Entomological Society of America 108,
117–129.
Lee, J.C., Wang, X., Daane, K.M., Hoelmer, K.A., Isaacs, R., Sial, A.A., Walton, V.M., 2019.
Biological Control of Spotted-Wing Drosophila (Diptera: Drosophilidae)—Current and
Pending Tactics. Journal of Integrated Pest Management 10, 13.
Lin, H., Phelan, P.L., 1991. Identification of food volatiles attractive to dusky sap beetle,
Carpophilus lugubris (Coleoptera: Nitidulidae). J. Chem Ecol 17, 1273–1286.
Louis, C., Girard, M., Kuhl, G., Lopez-Ferber, M., 1996. Persistance of Botrytis cinerea in its
vector Drosophila melanogaster. Phytopathology 86 (9): 934-939
Loughner, R.L., Loeb, G.M., Demchak, K., Schloemann, S., 2007. Evaluation of Strawberry Sap
Beetle (Coleoptera: Nitidulidae) Use of Habitats Surrounding Strawberry Plantings as Food
Resources and Overwintering Sites. Environmental Entomology 36, 1059–1065.
Loughner, R.L., Loeb, G.M., Schloemann, S., Demchak, K., 2008. Evaluation of Cultural
Practices for Potential to Control Strawberry Sap Beetle (Coleoptera: Nitidulidae). J. Econ.
Entomology 101, 850–858.
Maicas, S., Mateo, J.J., 2020. Sustainability of Wine Production. Sustainability 12 (2): 559.

53



Marcos, J., Carriço, R., Sousa, M.J., Palma, M.L., Pereira, P., Nunes, M.C., Nicolai, M., 2023.
Effect of Grape Pomace Flour in Savory Crackers: Technological, Nutritional and Sensory
Properties. Foods 12, 1392.
Marshall, S.A.,Woodley, N.E., Hauser, M., 2015. The historical spread of the Black Soldier Fly,
Hermetia illucens (L.) (Diptera, Stratiomyidae, Hermetiinae), and its establishment in
Canada. Journal of the Entomological Society of Ontario 146, 51-54.
Michigan State University Extension, 2004. Michigan Fruit Management Guide E-154.
Mishra, R., Chiu, J.C., Hua, G., Tawari, N.R., Adang, M.J., Sial, A.A., 2018. High throughput
sequencing reveals Drosophila suzukii responses to insecticides. Insect Science 25, 928–
945.
Mitsui, H., Takahashi, K.H., Kimura, M.T., 2006. Spatial distributions and clutch sizes of
Drosophila species ovipositing on cherry fruits of different stages. Population Ecology 48,
233–237.
Molina, J.J., Harrison, M.D., Brewer, J.W., 1974. Transmission of Erwinia carotovora var.
atroseptica by Drosophila melanogaster Meig. I. Acquisition and transmission of the
bacterium. American Potato Journal 51, 245–250.
Montoya, P., Flores, S., Toledo, J., 2008. Effect of Rainfall and Soil Moisture on Survival of
Adults and Immature Stages of Anastrepha Ludens and A. Obliqua (Diptera: Tephritidae)
under Semi-Field Conditions. Florida Entomologist 91 (4): 643–50.
Newton, L., Sheppard, C., Watson, D., Burtle, G., Dove, R., 2005. Using the Black Soldier Fly,
Hermetia Illucens, as a Value-Added Tool for the Management of Swine Manure. North
Carolina State University.
Nikolouli, Katerina, Hervé Colinet, Christian Stauffer, and Kostas Bourtzis, 2022. How the
Mighty Have Adapted: Genetic and Microbiome Changes during Laboratory Adaptation in
the Key Pest Drosophila Suzukii. Entomologia Generalis 42.
Nufio, C.R., Papaj, D.R., 2001. Host marking behavior in phytophagous insects and parasitoids.
Entomologia Experimentalis et Applicata 99, 273–293.
O’Brien, D.M., Min, K.-J., Larsen, T., Tatar, M., 2008. Use of stable isotopes to examine how
dietary restriction extends Drosophila lifespan. Current Biology 18, R155–R156.
Olazcuaga, L., Rode, N.O., Foucaud, J., Facon, B., Ravigné, V., Ausset, A., Leménager, N.,
Loiseau, A., Gautier, M., Estoup, A., Hufbauer, R.A., 2019. Oviposition Preference and
Larval Performance of Drosophila suzukii (Diptera: Drosophilidae), Spotted -Wing
Drosophila: Effects of Fruit Identity and Composition. Environmental Entomology 48, 867–
881.

54



Oliveira, F., Doelle, K., List, R., O’Reilly, J.R., 2015. Assessment of Diptera: Stratiomyidae,
genus Hermetia illucens (L., 1758) using electron microscopy. Journal of Entomology and
Zoology Studies 3(5):147-152.
Paggi, M., Nicholson, C.F., 2013. Federal and State Marketing Orders. US Programs Affecting
Food and Agricultural Marketing. Natural Resource Management and Policy 137–169.
Parra Paz, A.S., Carrejo, N.S., Gómez Rodríguez, C.H., 2015. Effects of Larval Density and
Feeding Rates on the Bioconversion of Vegetable Waste Using Black Soldier Fly Larvae
Hermetia illucens (L.), (Diptera: Stratiomyidae). Waste Biomass Valor 6, 1059–1065.
Peng, C., Williams R.N., 1991. Effect of Trap Design, Trap Height, and Habitat on the Capture
of Sap Beetles (Coleoptera: Nitidulidae) Using Whole-Wheat Bread Dough. J. Econ.
Entomology 84 (5): 1515–19.
Powell, G.S.,2015. A Checklist of the Sap Beetle (Coleoptera: Nitidulidae) Fauna of Indiana,
with Notes on Effective Trapping Methods. Insecta Mundi.
Prange, R., DeEll, J., 1997. Preharvest Factors Affecting Postharvest Quality of Berry Crops.
HortScience 32, 824–830.
Rehman, K. ur, Cai, M., Xiao, X., Zheng, L., Wang, H., Soomro, A.A., Zhou, Y., Li, W., Yu, Z.,
Zhang, J., 2017. Cellulose decomposition and larval biomass production from the codigestion of dairy manure and chicken manure by mini-livestock (Hermetia illucens L.).
Journal of Environmental Management 196, 458–465.
Rendon, D., Hamby, K.A., Arsenault-Benoit, A.L., Taylor, C.M., Evans, R.K., Roubos, C.R.,
Sial, A.A., et al. 2020. Mulching as a Cultural Control Strategy for Drosophila Suzukii in
Blueberry. Pest Management Science 76 (1): 55–66.
Rering, C.C., Quadrel, A., Urbaneja-Bernat, P., Beck, J.J., Ben-Zvi, Y., Khodadadi, F.,
Aćimović, S.G., Rodriguez-Saona, C., 2023. Blueberries infected with the fungal pathogen
Colletotrichum fioriniae release odors that repel Drosophila suzukii. Pest Management
Science 79 (12):4906-4920.
Rondon, S.I., Price, J.F., Cantliffe, D.J., 1969. Sap Beetle (Coleoptera: Nitidulidae) Management
in Strawberries. University of Florida IFAS Extension 2004.
Sato, A., Tanaka, K.M., Yew, J.Y., Aya Takahashi, A., 2021. Drosophila Suzukii Avoidance of
Microbes in Oviposition Choice. Royal Society Open Science 8 (1): 201601.
Schöneberg, T., Lewis, M.T., Burrack, H.J., Grieshop, M., Isaacs, R., Rendon, D., Rogers, M.,
Rothwell, N., Sial, A.A., Walton, V.M., Hamby, K.A., 2021. Cultural Control of Drosophila
suzukii in Small Fruit-Current and Pending Tactics in the U.S. Insects 12, 172.

55



Seehausen, M.L., Valenti, R., Fontes, J., Meier, M., Marazzi, C., Mazzi, D., Kenis, M., 2022.
Large-arena field cage releases of a candidate classical biological control agent for spotted
wing drosophila suggest low risk to non-target species. J. Pest Sci 95, 1057–1065.
Shaw, B., Brain, P., Wijnen, H., Fountain, M.T., 2018. Reducing Drosophila suzukii emergence
through inter-species competition. Pest Management Science 74, 1466–1471.
Shaw, B., Hemer, S., Cannon, M.F.L., Rogai, F., Fountain, M.T., 2019. Insecticide Control of
Drosophila suzukii in Commercial Sweet Cherry Crops under Cladding. Insects 10, 196.
Sheppard, C., 1983. House Fly and Lesser Fly Control Utilizing the Black Soldier Fly in Manure
Management Systems for Caged Laying Hens. Environmental Entomology 12, 1439–1442.
Sheppard, D.C., Tomberlin, J.K., Joyce, J.A., Kiser, B.C., Sumner, S.M., n.d. Rearing Methods
for the Black Soldier Fly (Diptera: Stratiomyidae). J. Med. Entomology 39, 4.
Silva-Soares, N.F., Nogueira-Alves, A., Beldade, P., Mirth, C.K., 2017. Adaptation to new
nutritional environments: larval performance, foraging decisions, and adult oviposition
choices in Drosophila suzukii. BMC Ecol 17, 21.
Singh, J.P., Mandal, B.K., 2000. Role of wrappers and post-harvest application of calcium nitrate
on the storage behaviour of sub-tropical litchi Cv. Manaraji. Journal of Applied Biology 10,
37–42.
Sirrine, R.J., 2006. Tart Cherry (Prunus Cerasus L.) Production in Northern Michigan:
Agroecological and Social Issues. Ph.D., University of California, Santa Cruz.
Souza, Mireli Trombin de, Souza, Michele Trombin de, Rizzato, F.B., Zawadneak, M.A.C.,
Cuquel, F.L., 2019. Feeding of Lobiopa insularis (Coleoptera: Nitidulidae) on strawberries.
Crop Protection 119, 180–184.
Spinei, M., Oroian, M., 2021. The Potential of Grape Pomace Varieties as a Dietary Source of
Pectic Substances. Foods 10, 867.
Stockton, D., Wallingford, A., Rendon, D., Fanning, P., Green, C.K., Diepenbrock, L., Ballman,
E., et al. 2019. Interactions Between Biotic and Abiotic Factors Affect Survival in
Overwintering Drosophila Suzukii (Diptera: Drosophilidae). Environmental Entomology 48
(2): 454–64.
Sturtevant, A.H.,1921. The North American Species of Drosophila. Carnegie Institution of
Washington.
Tait, G., Mermer, S., Stockton, D., Lee, J., Avosani, S., Abrieux, A., Anfora, G., Beers, E.,
Biondi, A., Burrack, H., et al. 2021. Drosophila suzukii (Diptera: Drosophilidae): A Decade
of Research Towards a Sustainable Integrated Pest Management Program. J. Econ.
Entomology 114, 1950–1974.
56



Thistlewood, H.M.A., Gill, P., Beers, E.H., Shearer, P.W., Walsh, D.B., Rozema, B.M.,
Acheampong, S., et al. 2018. Spatial Analysis of Seasonal Dynamics and Overwintering of
Drosophila Suzukii (Diptera: Drosophilidae) in the Okanagan-Columbia Basin, 2010–2014.
Environmental Entomology 47, (2): 221–32.
Tomberlin, J.K., Sheppard, D.C., Joyce, J.A., 2002. Selected Life-History Traits of Black Soldier
Flies (Diptera: Stratiomyidae) Reared on Three Artificial Diets. Annals of the
Entomological Society of America 95, 379–386.
USDA National Agricultural Statistics Service (dataset). 2023.
Van Timmeren, S., Isaacs, R., 2013. Control of spotted wing drosophila, Drosophila suzukii, by
specific insecticides and by conventional and organic crop protection programs. Crop
Protection 54, 126–133.
Vargas, O.L., Bryla, D.R., 2015. Growth and Fruit Production of Highbush Blueberry Fertilized
with Ammonium Sulfate and Urea Applied by Fertigation or as Granular Fertilizer. Hort.
Science 50, 479–485.
Walsh, D.B., Bolda, M.P., Goodhue, R.E., Dreves, A.J., Lee, J., Bruck, D.J., Walton, V.M.,
O’Neal, S.D., Zalom, F.G., 2011. Drosophila suzukii (Diptera: Drosophilidae): Invasive
Pest of Ripening Soft Fruit Expanding its Geographic Range and Damage Potential. J.
Integr Pest Manag 2, G1–G7.
Wang, X., Daane, K.M., Hoelmer, K.A., Lee, J.C., 2020. Biological Control of Spotted-Wing
Drosophila: An Update on Promising Agents. Drosophila Suzukii Management. Springer
International Publishing pp. 143-167.
Williams, R., M. Ellis, G. Keeney. 2017. A Bait Attractant Study of the Nitidulidae (Coleoptera)
at Shawnee State Forest in Southern Ohio. The Great Lakes Entomologist 27 (4).
Wilson, J., Gut, L., Rothwell, N., Haas, M., Pochubay, E., Powers, K., Whalon, M., Wise, J.,
2019. Managing Spotted Wing Drosophila in Michigan Cherry. Michigan State University
Extension.
Woltz, J.M., Lee, J.C., 2017. Pupation behavior and larval and pupal biocontrol of Drosophila
suzukii in the field. Biological Control 110, 62–69.
Yadav, V.K., Singh, H.K., 2002. Effect of preharvest application of calcium nitrate, Topsin-M
and Bayleton on postharvest life of aonla (Emblica officinalis Gaertn.) fruit. J. Appl. Hort. 4
(2): 83–86.
Zalom F, Weakley C, Hendricks L, Bentley W, Barnett W, Connell J. 1984. Cultural
management of the navel orangeworm by winter sanitation. Calif Agr 38(3):28

57



APPENDIX A. RECORD OF DEPOSITION OF VOUCHER SPECIMENS

58



APPENDIX B. CHAPTER 1 SUPPLEMENTARY MATERIAL
Table B.1 GPS coordinates accurate within 3.8m for each experimental replicate per location
per year including cherry cultivar. Logged using GPS Logger ver. 3.2.1 (BasicAirData, Paris,
FR) and processed with GPX Viewer ver. 1.41.2 (Vectura Games OU, Tallinn, EE).
Location code
A
A
A
A
B
B
B
B
BB
BB
BB
BB
C
C
C
C
D
D
D
D
G
G
G
G
GG
GG
GG
GG
A
A
A
A
A
A

Treatment
Control
Crushed
15% Manure
25% Manure
Control
Crushed
15% Manure
25% Manure
Control
Crushed
15% Manure
25% Manure
Control
Crushed
15% Manure
25% Manure
Control
Crushed
15% Manure
25% Manure
Control
Crushed
15% Manure
25% Manure
Control
Crushed
15% Manure
25% Manure
Control
Crushed
15% Manure
25% Manure
Seed Control
Urea

GPS coordinates
45.009864, -85.644006
45.007657, -85.641816
45.008375, -85.642650
45.009173, -85.643197
44.884993, -85.670074
44.884126, -85.670087
44.885091, -85.668656
44.884039, -85.668776
44.883220, -85.668487
44.882486, -85.669206
44.883393, -85.669801
44.882542, -85.667831
44.883223, -85.680222
44.883362, -85.679106
44.882482, -85.678079
44.882441, -85.680421
44.896264, -85.678967
44.896276, -85.674789
44.896295, -85.677473
44.896340, -85.676330
45.136641, -85.650824
45.135776, -85.650503
45.138618, -85.651807
45.137589, -85.651276
45.135792, -85.648505
45.136753, -85.648963
45.137838, -85.649377
45.140211, -85.650452
45.009673, -85.643796
45.010409, -85.644731
45.008292, -85.642503
45.007595, -85.641761
45.009152, -85.643008
45.010927, -85.645219

59

Year
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2021
2022
2022
2022
2022
2022
2022

Cherry cultivar
Montmorency
Montmorency
Montmorency
Montmorency
Emperor Francis
Emperor Francis
Emperor Francis
Emperor Francis
Emperor Francis
Emperor Francis
Emperor Francis
Emperor Francis
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Blushing Gold
Blushing Gold
Blushing Gold
Blushing Gold
Blushing Gold
Blushing Gold
Blushing Gold
Blushing Gold
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency



Table B.1 (cont’d)
Location code
B
B
B
B
B
B
C
C
C
C
C
C
D
D
D
D
D
D
E
E
E
E
E

Treatment
Control
Crushed
15% Manure
25% Manure
Seed Control
Urea
Control
Crushed
15% Manure
25% Manure
Seed Control
Urea
Control
Crushed
15% Manure
25% Manure
Seed Control
Urea
Control
Crushed
15% Manure
25% Manure
Seed Control

GPS coordinates
44.882652, -85.669950
44.885185, -85.670049
44.884408, -85.668486
44.885130, -85.688784
44.882740, -85.667927
44.883648, -85.667954
44.885206, -85.678844
44.885226, -85.680407
44.885225, -85.681789
44.885205, -85.683614
44.884990, -85.684727
44.885207, -85.677429
44.896278, -85.678779
44.896276, -85.676167
44.896282, -85.675038
44.896202, -85.673941
44.896283, -85.680490
44.896260, -85.677485
44.882534, -85.680609
44.881796, -85.680661
44.881839, -85.679559
44.881957, -85.678771
44.883338, -85.680547

60

Year
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022
2022

Cherry cultivar
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency
Montmorency