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THE YIELD OF TOMATOES, CUCUMBERS, AND
SWEET CORN WITH ALFALFA HAY APPLIED AS A
SIDEDRESSING

Thesis for the Degree of M. S.
MICHIGAN STATE UNIVERSITY
GEORGE DAMIAN MORRIS
1977

ABSTRACT

THE YIELD OF TOMATOES, CUCUMBERS, AND
SWEET CORN WITH ALFALFA HAY APPLIED AS A SIDEDRESSING

By

George Damian Morris

Air dried alfalfa hay (Medicago sativa L. cv. 'Vernal') was shredded

 

and evenly applied at planting in a band beside and below vegetable seed

in field experiments. Tomato (Lycopersicon esculentum L. cv. 'Campbell

 

1327') and cucumber (Cucumis sativa L. cv. 'Green Star') tests were con-

 

ducted at two locations. Sweet corn (§E§.EEX§.L° cv. 'Spring Gold') was
tested at one location. One hundred to 400 kilograms per hectare of
alfalfa hay did not increase yields of these crops when compared to con-
trols receiving equal levels of mineral fertilizer. Supplemental nitro—
gen applications increased the yield of tomatoes and sweet corn at one
location. Tomatoes treated with alfalfa hay had equivalent yields to
treatments receiving starter solution at planting. On a medium ferti-
lity soil, tomato yields of both the 200 kilogram per hectare of alfalfa
hay plus starter and the starter solution treatments were as high as

supplemental nitrogen treatments receiving starter fertilizer solution.

THE YIELD OF TOMATOES, CUCUMBERS, AND

SWEET CORN WITH ALFALFA HAY APPLIED AS A SIDEDRESSING

By

George Damian Morris

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of
MASTER OF SCIENCE
Department of Horticulture

1977

ACKNOWLEDGMENTS

I wish to thank the following persons: my advisor, Dr. Stanley
K. Ries, for guidance, insight, and aid in my research and writing;
Drs. Alan Putnam and George Ayers for their support and constructive
criticism of my writing; Drs. Hugh Price and James Notes for their
excellent help in the field and willingness to provide needed cultural
information; Mrs. Violet Wert, for technical advice and moral support;
my parents, Evelyn and George Morris, who have always strengthened
and help guide my efforts; and finally, graduate students and friends
who have aided, guided, and provided moral support in my research, L.
Kolker, R. Hangarter, H. Bittenbender, T. Richman, A. Lockwood, and

A. Carpenter.

ii

List of Tables ..

Introduction ....

Literature Review

TABLE OF CONTENTS

OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO

Materials and Methods ..........................................

Results and Discussion .........................................

Literature Cited

OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO

iii

Table No.

l.

L\

LIST OF TABLES

Available Nutrients and Recommended Fertilizer
Applications Rates for Sodus and East Lansing

in 1976.

Plot Dimensions and Cultural Practices Utilized
in Growing Direct Seeded Tomatoes and Cucumbers
at Sodus and East Lansing.

Response of Direct Seeded 'Campbell 1327' Tomatoes
to Band Applications of Alfalfa Hay at Sodus and
East Lansing.

Response of 'Campbell 1327' Tomatoes to Band
Applications of Alfalfa on Two Soil Fertility
Levels at East Lansing.

Yield in Dollars per Hectare of 'Green Star'
Cucumbers at Sodus and East Lansing Following
Organic Matter Additions at Planting (three
harvests were made at each location).

Response of 'Spring Gold' Sweet Corn to Band
Applications of Alfalfa Hay and Broadcasted

Fertilizers at East Lansing.

iv

Page No.

10

14

’16

19

21

INTRODUCTION

The incorporation of existing crop residues and the broadcast
application and incorporation of added organic materials at high rates
may improve the physical properties of soils. The effect of band appli-
cations of organic matter in crop production and their potential physio—
logical consequences have not been established. Ries et al. (1976) re—
ported that band applications of alfalfa hay at rates as low as 234
kilograms per hectare increased the early yields of direct seeded
tomatoes and cucumbers. This could not be explained on the basis of
the nitrogen available from the hay. Math and Suryanarayana (1927)
increased seedling growth of wheat, tomatoes, and other plants by adding
yeast at two milligrams per kilogram of sand in sand culture and Ruiz
and Etchevers (I975) improved the physical properties of a soil by
adding seaweed at the rate of about two metric tons per hectare in
container experiments. These additions of organic matter may have
marked effects on early plant growth, resulting in yield increases.

Band applications of organic matter with a gradual release of nutrients
and organic substances in the root zone of seedlings could maximize

the effects. The purpose of this study was to evaluate the merits of
alfalfa hay applied as a band sidedressing in the production of several

vegetable crops.

LITERATURE REVIEW

Stimulation of plant growth by organic matter, especially prior
to 1940, was frequently confused by the lack of micronutrients in con-
trols and poor control of microorganisms. It was difficult to deter-
mine if the cause of the stimulation was the organic matter or microbial
decomposition products (Swaby 1942). In conducting research with soils
and organic matter, no reaction that may occur in the soil should be
ignored until it is proven unimportant for the system under study
(Patrick et al. 1964). Although plants can have optimum growth with
only inorganic nutrients (Patrick et al. 196A), plants grown in a
microbe-free system are usually smaller than plants grown in contami—
nated systems (Lindsey 1967). The lack of some plant requirement in
the microbe—free system and the production of growth regulators by
saprophytic microorganisms were suggested as possible explanations for
larger plants in microbe—contaminated systems (Lindsey 1967).

Comprehensive reviews have been written on soil microorganisms
and plant growth substances (Schmidt 1951), rhizosphere relations
(Starkey 1958), and phytotoxic substances from soil microorganisms and
crop residues (McCalla and Haskins 1964; Patrick et al. 1964).

Organic matter affects soil fertility by improving soil structure,
increasing water holding capacity, increasing buffering and exchange
capacity, and supplying nutrients (Bremner I956). The fertility of
coastal plain soils is largely determined by the organic matter

content of the soil (Hester and Shelton 1937).

[Q

Organic matter additions to soils may increase carbon dioxide levels
in the soil and the availability of soil phosphorus (Stanford and Pierre
1953). Water extracts of decomposing organic matter may also increase
phosphorus availability. Increased microbial levels from organic sup—
plements may produce additional anions that can replace soil phosphates.
Organic supplements can also decrease the capacity of soils to fix
added phosphorus (Hester and Shelton 193%; Stanford and Pierre 1953).

The quantity of nutrients released from organic matter is the sum
of mobilization and immobilization. Mobilization or mineralization of
nutrients from materials occurs only if the nutrient is in excess of
that needed for microbial growth in the decomposition process. Materials
with 1.2 to 2.6 percent nitrogen content, and carbon to phosphorus ratios
of less than 200 tend to mineralize readily (Black 1968). Alfalfa,
usually high in nitrogen, phosphorus, and organic substrates mineralizes
its nutrients rapidly. Nitrogen released from alfalfa hay was found to
be 63 percent as efficient as ammonium nitrate applied at the rate of
31 kilograms of nitrogen per hectare (Fribourg and Bartholomew 1956).
Shaw and Robinson (1960) found that the best nitrogen utilization from
added soybean hay resulted with shallow soil incorporations.

Plant materials usually have about two thirds of their phosphorus
content in the organic form (Black 1968). Organic phosphorus has a
greater extended mobility in soils than inorganic phosphorus (Renner
1965; Black 1968). This supports the idea that the biologically effec—
tive quantity of each form may not be the same (Wier and Black 1968).

In phosphorus uptake studies, Fuller and Hannapel (1958) showed that
uptake from added plant residues is greater on soils low in phosphorus

than soils high in phosphorus demonstrating that organic matter additions

can be important on low fertility soils.

Other nutrients may also be more available in soils where organic
matter additions are made. Potassium may be more available due to in-
creased mobility of potassium from clover (Locatusu 1975) and organic
matter additions (Aslander and Armolik 1964). Alfalfa amended soils
have increased release of soil copper (Hurwitz 1948), iron and manganese
(Elliot and Blaylock 1975).

Although the organic matter content of cultivated soils is re-
ported to remain constant (Joffe 1955), numerous short term effects of
adding organic matter to the soil have been documented. The addition
of ryegrass (Broadbent 1948) and alfalfa (Bingeman et al. 1953) are re—
ported to increase the decomposition of soil organic matter. This
increase in decomposition of soil organic matter by added organic mat-
ter has been termed the 'priming action'. The priming effect lasts
longer in soils low in organic matter (Sauerbeck 1966). Organic matter
high in nitrogen causes an accumulation of ammonium inducing an increase
in pH which can increase soil microbial activity (Barrow 1960). Micro-
bial activity increases the production of carbon dioxide, sulfate, and
the mineralization of nitrogen from the soil organic matter. In con-
trast, Mortenson (1963) reported that increased additions of organic
matter decreased the breakdown of soil organic matter. These conflict—
ing results in soil organic matter studies may be due to variability of
.soils or the procedures used by each experimenter.

Plant residues are known to contain substances toxic to other
plants. Detrimental effects to plant growth have been reported from
plant toxins (Bonner 1950), plant extracts (Le Tourneau et al. 1956),

water soluble extracts of straw (Guenzi and McCalla 1962; Kimber 1967,

1973a, 1973b), alfalfa extracts (Nielson et al. 1960), and alfalfa
saponins (Pederson 1965; Shany et al. 1970). Extracts from one
variety of wheat straw decomposed for two days stimulated wheat root
growth by 40 percent (Kimber 1967). With increasing decomposition
times, the toxicity of plant residues usually decreases. After one
month of decomposition, stimulatory effects were observed from plant
residues (Patrick et a1. 1963). Generally, substances that inhibit
germination have stimulatory effects on germination at more suitable
concentrations (McCalla and Haskins 1964).

Added organic materials can exert unique effects on soil micro—
organisms. Soybean meal in a 0.5 percent mixture with soil stimulated
actidione (antifungal antibiotic) production while alfalfa caused no
effect at the same rate (Gottlieb et a1. 1952). Alfalfa juice which
is rich in protein, carbohydrates, vitamins, and minerals was shown

to increase Bacillus subtilis growth (Bickoff et al. 1968). Volatile

 

substances from fresh cut and dried alfalfa hay can increase microbial
respiration (Menzies and Gilbert 1967). Methanol and several aldehydes
were identified as the volatile compounds from alfalfa hay residues

that stimulate germination and decrease the survival of Sclerotium

 

rolfsii. Alfalfa saponins were shown to arrest the growth of S,
rolfsii (Gestetner et al. 1971). Volatile aldehydes and alcohols from
other plants were found to change the composition and activity of soil
microflora (Owens et a1. 1969) indicating the complex relationship
between organic matter and biological systems.

Organic amendments may also affect disease incidence caused by
soil-borne pathogens by increasing the biological buffering capacity

of the soil, reducing the pathogen numbers during anaerobic

decomposition of organic matter, and by affecting nitrification (Huber
and Watson 1970). Alfalfa additions increased nitrification and tended
to reduce the incidence of fusarium and rhizoctonia root rot in
Phaseolus s3. (Huber et al. 1965). Organic matter additions have been
used to stimulate plant pathogen antagonists, but the results are un-
predictable (Baker and Cook 1974).

Additions of soil microbial isolates to sterile cultures of intact
higher plants have accelerated the growth of young plants. Of the 2.4
percent (81 total) of the isolates that accelerated growth, many in-
creased growth 50 percent over control treatments (Hata 1962). Anti—
biotics, such as Penicillin G and Bacitracin, have stimulated the growth

of Lemna minor in aseptic culture tests (Nickell and Findlay 1954).

 

Penicillium urticae 'Bainer', frequently associated with straw decompo-

 

sition in soils, produces a phytotoxic substance (patulin) which at 75
ppm inhibited wheat shoot growth in soil cultures by 50 percent and at
0.01-10.00 ppm acted as an auxin synergist (Norstadt and McCalla 1963).
Associations of growth regulators with the soil and organic materi-
als are currently of great interest in agricultural research. Gross
(1975) discussed natural growth regulators which are involved in plant
growth, but apparently do not show specific action or function. Aliphatic
hydroxycarboxylic acids, neutral lipids, tannins, dihydroconiferyl alco—
hol, and Strigol stimulate plant growth, most of which have been shown
to interact directly with plant hormones. Kampert et al. (1972) stated
that added organic matter could slow down auxin decomposition in soils
enough to be ecologically significant for plant growth. Less optimistic
views are reported by Audus (1963) after reviewing earlier literature.

On a well fertilized soil it is unlikely that vitamins or auxins from

added organic matter would stimulate plant growth unless stimulation
occurred from some presently unidentified substance or by direct
effects from microfloral associations with plant roots (Audus 1963).
Organic matter additions to soils with the formation of humus sub-
stances are an important factor in the maintenance of soil fertility.
Kononova (1966) reviewed the history, formation, and the significance
of these substances. Humus substances are formed mainly from the de—
composition products of plant and animal residues. They consist of a
heterogeneous mixture of molecules which can be extracted from soils by
alkaline solutions. Humic acids are precipitated from the alkaline ex-
tract upon acidification. The other main fraction of humus substances,
fulvic acids, remain in solution upon this acidification. Increased
tomato yields by foliar sprays of sodium humate at 10 ppm (Varshney and
Gaur 1974) and earlier flowering of tomatoes from humic acid root dips
of seedlings (Stanchev 1972) have been reported. Other beneficial
effects attributed to humus substances are: the inhibition of phosphorus
fixation (Hashimoto et a1. 1969), increased phosphorus utilization
(Jelenié et al. 1963), increased root growth (Ivanova 1965), and improved
crop growth under non-optimal conditions (Niggeman 1965; Guminska and
Gracz-Nalepka 1972). Early explanations of humic acid growth promotion
were centered mainly on its chelating effects (Burk et al. 1932, De Rock
1955). Recent studies have shown increased plant growth and the movement
of small quantities of labeled humic acids into plants (Fuhr and Sauerbeck
1966). Humic acids improved growth of wheat plants in sterile solution
culture systems. This established that humic acids enter the plant and
have direct physiological effects (Vaughan and Linehan 1976).

Several other plant stimulating substances related to the organic

matter discussion are naphthenic acids and triacontanol. Naphthenic
acids or petroleum growth substances are a complex mixture of acids
prepared from petroleum that have been shown to cause a general stimu-
lation of plant biochemical processes and increase crop yields. It
appears that an increased photosynthetic efficiency results upon
foliar application resulting in increased yields of many crops (Wort
1976). Triacontanol, isolated from alfalfa hay, has been shown to
stimulate plant growth by applications to the foliage or roots (Ries
et al. 1977). The literature reviewed here indicates that organic
matter additions may have significant roles in crop production due

to factors recently considered unimportant.

MATERIALS AND METHODS

Direct seeded 'Campbell 1327' tomatoes and 'Green Star' cucumbers
were planted at Sodus and East Lansing on Oshtemo loamy sand (0.96%
organic matter) and Spinks loamy sand (1.47% organic matter) soils
respectively. Soil tests indicated that experimental sites at both
locations required supplemental fertilization (Table 1). Soil micro-
nutrient levels were considered satisfactory based on past crOpping
histories, pH ranges of soils (6.4-6.7), and soil tests for manganese
and zinc at East Lansing.

At Sodus, sudan grass was grown the previous season at the tomato
test location and a vegetable crop grown previously at the cucumber
site. Both sites were fall-seeded with rye, broadcasted with 78 kg/ha
of nitrogen as urea in the early spring, then plowed before planting.

Vegetables were grown previously at the tomato test location and the

land was fallow prior to the cucumber test conducted at East Lansing.
Forty kg/ha of nitrogen (N), phosphorus (P205), and potassium (K20)
was broadcast and disked into the soil on April 15 at the East Lansing
site.

A randomized complete block design with four blocks in each ex-

periment was used with the exception of the tomato test at East Lansing,

Table 1. Available Nutrients and Recommended Fertilizer Application

Rates for Sodus and East Lansing in 1976.1

 

LOCATION CROP SITE SOIL TEST (PPM) RECOMMENDED FERTILIZER

APPLICATION - RATE2 (kg/ha)

 

 

P K P205 K20
SODUS3 ' TOMATO 47 156 168 56
CUCUMBER 92 192 28 —-
EAST LANSING” TOMATO 36 44 168 .336
CUCUMBER 36 44 56 224
SWEET CORN 36 44 56 224

 

1Soils tested by the Michigan State University Soil Testing Laboratory.
Available soil phosphorus determined by Bray Pl extraction. Available
soil potassium determined by 1.0 N neutral ammonium acetate extraction.
2Commercial Vegetable Recommendations for Michigan, Cooperative Extension
Service, Michigan State University, April 1970.

3Soil test samples taken in the fall of 1975.

L’Soil test samples taken in the spring of 1976.

10

where a factorial experiment in a split plot design was used. The main

plots were 40 kg/ha of P 2

O and K

2 5 0 versus 80 kg/ha of P20

5 and K00.
Each experiment had seven or eight treatments. Row spacings, plot

lengths, and harvested plot lengths are listed in Table 2.

Table 2. Plot Dimensions and Cultural Practices Utilized in Growing

Direct Seeded Tomatoes and Cucumbers at Sodus and East Lansing.

 

 

 

 

PLOT DIMENSIONS (METERS) TOMATOES CUCUMBERS
SODUS E.L. SODUS E.L.
Row Spacing 1.50 1.50 1.20 1.20
In-Row Spacing 0.46 0.46 0.38 0.20—0.30
Plot Length 7.60 7.60 7.60 6.10
Harvested Plot Length 7.60 7.00 7.50 5.50

 

PRACTICE AND DATE PERFORMED

 

Planting 5/12 5/20 5/27 6/3
Planting Time N 5/27 6/5
Thinning 6/23 6/14 6/28 6/14
6/28
Sidedressing 7/19 7/8
Sidedressing N Supplement 7/12 7/15
Harvest(s) 8/30 8/26 7/22 7/21
9/10 7/27 7/26
8/3 7/31

 

Bales of second cutting 'Vernal' alfalfa hay harvested in 1975 con—

taining 2.82% nitrogen (as determined by micro—Kjeldahl analysis) were

11

used for alfalfa applications. Alfalfa was shredded as an air dry hay
with a Wiley mill without a seive screen. This texture accommodated
manual band applications of 100-400 kg/ha of alfalfa hay. Agricultural
grade alfalfa meal, alfalfa pellets, and soybean meal containing 2.7,
2.7, and 7.68% nitrogen respectively, were sidedressed in cucumber tests
but not tomato tests. Placement of the band applications beside and
below the seed was achieved by spreading the organic materials by hand
in a trench (5 to 7.5 cm deep) previously dug to the side of the marked
row, covering the trench, and seeding with a planter. The tomato and
cucumber rows were seeded approximately 2.5 and 5 cm respectively to
the side of the band of organic supplements. Seeding depth was 2.0 cm
for tomatoes and 2.5 to 3.5 cm for cucumbers.

Direct seeded tomatoes received a pre-emergence spray of diphenamid
at 4.48 kg/ha within one day after seeding followed by an application
of 1.5 cm of water by overhead irrigation to incorporate the herbicide
and enhance uniform germination. Cucumbers at Sodus were sprayed with
2.24 kg/ha of chloramben methyl ester immediately after planting, fol—
lowed by overhead irrigation. No herbicide was applied to the cucum-
bers at East Lansing. The crops were irrigated, weeded, cultivated,
and protected from pests.

Tomatoes were planted with a Dahlman clump planter adjusted to
drop about 6 seeds as a group 23 cm apart in the row. Starter solution
was sprayed on the seeds in the row just prior to soil covering of the
seed by the planter. Nitrogen at 2.2 kg/ha and P205 at 7.5 kg/ha were
applied in the starter solution at both locations. An additional 1.9

kg/ha of K 0 was applied at East Lansing in the starter solution. At

2

East Lansing, a loose starter hose connection during planting required

12

that two blocks be sprayed with the starter on the soil surface on top
of the row. No attempt was made to thin seeded clumps allowing the
establishment of 3 to 12 plants per clump. About two weeks after
seeding urea was applied, at 56 kg/ha, 2.5 cm deep and 25 cm to the
side of designated rows. In mid—June, experiments were thinned to
every other clump leaving 46 cm between clumps. Due to heavy rains

in late June, an additional 20 kg/ha of N as ammonium nitrate was
sidedressed on all treatments in East Lansing. Tomatoes were harvested
at the breaker stage. One harvest was made at Sodus and two harvests
were made at East Lansing (Table 2). The total number and weight of
fruit greater than 3.5 cm were recorded from each plot.

Cucumbers were planted at the rate of 10 to 15 seeds per meter of
row with a V-belt planter at Sodus and a cone planter at East Lansing.
The cucumbers at Sodus were thinned to 20 plants per plot due to poor
emergence. They were thinned to 20 to 30 cm between plants at East
Lansing. Fifty kg/ha of N as ammonium nitrate was applied as a side-
dressing to all cucumbers treatments in East Lansing due to the appear-
ance of nitrogen dificiency symptoms. Three harvests of fruit greater
than 2.5 cm long were made at each location (Table 2). The harvested
fruit from each plot were sized into four standard grades and the total
number and weight of fruit for each grade was recorded. Grades were
assigned values based on research standards.

'Spring Gold' sweet corn was planted at East Lansing to examine
the effects of sidedressed alfalfa applications, broadcasted nitrogen,
and broadcasted phosphorus and potassium on the early yield of sweet
corn. Vegetables were grown the previous season and radishes were har—

vested and disked down prior to the planting of sweet corn at this site.

The same main plots and subplots of the preceding radish experiment
were used for the sweet corn experiment in a split-split plot design.
The same sub-subplots of alfalfa treatments in the previous four block
radish experiment were not utilized due to the wider sweet corn row
spacing. An additional 40 kg/ha of N as urea was broadcasted and in-
corporated to the high N main plots. With this application, the total
applied fertilizer for the season to the two main plots was 40 or 120
kg/ha of N and the two subplots received both P205 and K20 at the rate
of 40 or 140 kg/ha. Row spacings of 0.9 meters and plot lengths of
7.3 meters were used for the sweet corn planting. Sub-subplots con—
sisted of three rates of alfalfa hay (0, 100, and 300 kg/ha) which
were banded 2.5 to 7.5 cm to the side and 2.5 to 5.0 cm below the ex-
pected seed placement. On June 18, the sweet corn was planted 5 cm
deep at the rate of 10 to 15 seeds per meter of row with a cone planter.
A post emergence spray of 0.6 kg/ha of atrazine was applied for weed
control. A week later the plants were thinned to 20 to 25 cm apart.
One main harvest was taken on August 25 with the weight (unhusked)

and number of horticulturally mature ears recorded from 6.4 meter

sections of each plot.

RESULTS AND DISCUSSION

At Sodus, early seedling growth of tomatoes was curtailed by a
severe wind storm. One harvest of tomatoes was made at Sodus to examine
early yield; no treatment response could be detected (Table 3). Early
growth of tomatoes at East Lansing was excellent. A nitrogen defici—

ency developed after heavy rains in late June in treatments not

13

14

Table 3. Response of Direct Seeded ’Campbell 1327' Tomatoes to Band

Applications of Alfalfa Hay at Sodus and East Lansing.

 

 

 

 

 

 

 

 

 

TREATMENT (kg/ha) YIELD (metric tons/ha)
PLANTING TIME SIDEDRESSING SODUS EAST LANSING
STARTER ALFALFA N ALFALFA N
+ --- 56 --- 28 20 2 43 9
+ -—- -— ——— -— 16.7 38 3
+ 200 -- --- -- 19.2 41 9
+ ——- -- 200 -- 21.6 36 7
+ 200 -- 200 -- 18.0 43.2
+ 400 -- -—- -— 18.4 37.2
+ 400 56 --- 28 22.3 46.4
4 400 . —- --- —- 19.0 35.2
L.S.D. at 0.05 level N.S. 6.3
L.S.D. at 0.01 level N.S. 8.7

 

scheduled for nitrogen applications. Two harvests of tomatoes were
made at East Lansing. Highly significant yield increases (based on the
individual F tests) were obtained by nitrogen applications (56 kg/ha of
N after planting and 28 kg/ha of N at flowering) compared to other
treatments receiving starter solutions (Table 3). A nitrogen response
was expected on this sandy soil. The yield of the alfalfa band treat-
ment (400 kg/ha at planting) with N applications was the same as from

the N applications alone. The alfalfa treatment without starter or

15

nitrogen applications yielded as well as the starter fertilizer control;
however, the alfalfa treatment with starter solution also yielded the
same as the starter fertilizer control. This indicates that the addi—
tion of alfalfa had no effect on yield if starter was applied at planting.

No interaction occurred between the treatments and fertilizer levels
(main plot) in the tomato test at East Lansing (Table 4). Clearly, at
the low fertility, only the N applications without alfalfa increased
tomato yields. This implies that alfalfa at 400 kg/ha may have had
detrimental effects on tomatoes in the low fertility soil. Another ex—
planation may be that a nutrient imbalance occurred due to an excess
of nitrogen with respect to a low potassium level in the soil resulting
in a decreased yield (Paterson 1974).

Results obtained in 1976 with 'Campbell 1327' tomatoes contradict
findings reported with 'Heinz 1350' tomatoes in 1975 (Ries et a1. 1976).
In the studies reported here, increased early plant growth was not ob-
served and no increase in early yield was obtained from alfalfa side;
dressings. Improved nitrogen (Qureshi et al. 1972) and phosphorus sup—
plies (Murphy 1964) are known to increase plant height of tomatoes and
may explain the increased height of alfalfa treatments noted in 1975.
There were no observed differences in vigor or height in 1976. A nu—
trient effect from alfalfa is further suggested by work of Ogle et al.
(1964) where additions of nitrogen and phosphorus (P205) up to 112 kg/
ha increased tomato yields on a similarly low fertility soil; in 1975
(Ries et al. 1976) applied only 36 kg/ha of N, P205, and K20. The fol-
lowing reasons are suggested for the lack of response to alfalfa band
applications in 1976 compared to 1975: the use of starter ferti—

lizer; heavy rains earlier in the growing season; use of different

16

Table 4. Response of 'Campbell 1327' Tomatoes to Band Applications of

Alfalfa on Two Soil Fertility Levels at East Lansing.1

 

 

 

 

 

 

 

 

TREATMENT (kg/ha) YIELD (metric tons/ha)
PLANTING TIME SIDEDRESSING SOIL FERTILITY LEVEL
STARTER ALFALFA N ALFALFA N LOW MEDIUM
+ --- 56 --- 28 45.5 43.9
+ --- —— —-— —- 33.8 38.3
+ 200 -- ~-- -- 37.4 41.9
+ -—- -- 200 -- 37.8 36.7
+ 200 -- 200 -- 34.0 43.2
+ 400 —- --- -- 33.4 37.2
+ 400 56 ——- 28 34.9 46.4
- 4OO -- --- -- 34.9 35.2
L.S.D. at 0.05 level 6.9 6.3
L.S.D. at 0.01 level 9.4 8.7

 

1The low fertility level soil received a base fertilizer application of
40 kg/ha of N,P205, and K20. The medium fertility level soil received

the base level application plus an additional 40 kg/ha of P205 and K20.

cultivars of tomato and alfalfa; and the use of clump planting rather
than thinning to single plant stands.

Application of high phosphorus starter solutions to tomatoes at
transplanting has been shown to increase early yields of tomatoes

(Sayre 1938); Jones and Warren 1954) with the response rapidly decreased

17

as phosphorus additions to soils are increased (Arnold 1953). The ready
availability of phOSphorus stimulated early growth of tomatoes which re-
sults in the development of a greater number of flowers earlier by
speeding up flower differentiation (Yamashita and Yoshiak 1963;
Takahashi et al. 1973). This increased early growth leads to a higher
yield and earlier maturity (Hepler 1922). Banded phosphorus applied

5 to 7.5 cm below tomato seed was seven times as efficient as broad-
casted phosphorus on direct seeded tomatoes in a field situation (Hipp
1970). The benefits from these phosphorus applications are similar to
those obtained from alfalfa additions on tomatoes in 1975 without banded
starter fertilizer. Starter fertilizer solutions used in the 1976
tomato tests clarified this point showing that alfalfa additions did

not improve yields above that of starter solution.

Heavy rains (5 cm) on June 30 in 1976, caused a premature nitrogen
stress on tomatoes at East Lansing about two months earlier than noted
in 1975. This deficiency was corrected by a nitrogen application to
all treatments. This stress or the leaching of substances from the
alfalfa treatments may also explain the difference in results between
1975 and 1976.

The toxicity of alfalfa extracts may vary with the year and cutting
of alfalfa (Guenzi et al. 1964) and alfalfa constituents as saponins
may vary between alfalfa varieties (Hanson et a1. 1963). Differences
between alfalfa cultivars with respect to plant growth response in the
field were not studied. It has been determined by Chibnall (1933) that
alfalfa contains approximately 100 ppm triacontanol on a dry weight
basis. At this concentration, 100 kg/ha of alfalfa hay contains 10 gm

of triacontanol. This level is far in excess (1000 fold - based upon

18

1000 E/ha of 10 ug/£ of triacontanol) of the amount found to increase
plant growth from both nutrient and foliar applications (Ries et al.
1977). No field tests were designed Specifically to test tomato culti-
var differences based on the marked responses obtained in 1975 field
tests, greenhouse tests, and the apparent general nature of the side~
dressing study.

Clump planted tomatoes, with two to four seeds per clump, yield
the same and have a more concentrated fruit set than tomatoes which
are thinned to one plant at a given plant spacing (Purdue University
1966). Clumps of over six plants at each within the row plant spacing
were common at East Lansing. The possibility of altered nutrient
requirements and other growth response patterns in relation to alfalfa
additions in 1976 from this plant competition deserves consideration.

'Green Star' cucumbers did not respond to sidedressings of alfalfa
hay, commercial alfalfa products, or soybean meal at Sodus or East
Lansing when compared to controls (Table 5). Despite poor seedling
emergence at Sodus, good foliage development and yields were obtained.
At East Lansing, emergence was excellent; nevertheless, poor growth
occurred throughout the season indicating a nutrient deficiency.
Noting these problems, a late planting of 'Green Star' cucumbers was
made at East Lansing on July 12 (data not presented). In this plant—
ing band treatments of 100 and 200 kg/ha of 'Vernal' alfalfa were
spread directly on top of a mineral fertilizer band (40 kg/ha of N,
P205, and K20) that was beside and below planted cucumber seeds. Al—
though excellent emergence and growth occurred in this late planting,
no yield benefits resulted from alfalfa treatments with fertilizer when

compared to fertilizer controls. Banded applications of phosphorus are

19

Table 5. Yield in Dollars per Hectare of 'Green Star' Cucumbers at
Sodus and East Lansing Following Organic Matter Additions at

Planting (three harvests were made at each location).

 

 

 

 

TREATMENT RATE YIELD ($/ha)
(kg/ha) SODUS EAST LANSING

CONTROL --- 1018 349
UREA 56 N ---- 340
ALFALFA HAY 100 1080 378

" " 200 1023 408

" " 400 1010 375
ALFALFA MEAL 200 1040 359
ALFALFA PELLETS 200 1085 339
SOYBEAN MEAL 60 1048 361
F RATIO N.S. N.S.
c.v. (2) 11.3 14.3

 

more efficient than broadcast applications in supplying phosphorus
(Baker and Mortenson 1965) and may explain the early yield response of
'Earlipik' cucumbers reported by Ries et al. (1976) from alfalfa addi-
tions.

'Spring Gold' sweet corn at East Lansing developed nitrogen defi—
ciencies as the season progressed. No additional nitrogen was applied
in order to observe treatment effects. Sweet corn sidedressed with

alfalfa hay at 100 or 300 kg/ha had equivalent yields to controls

20

receiving no alfalfa (Table 6). No interactions occurred between the
nitrogen, phosphorus and potassium, or alfalfa levels. The high level
of nitrogen (120 kg/ha of N) gave a 31% increase in fresh weight yield
of unhusked ears over the low nitrogen level (40 kg/ha of N). Alfalfa
additions did not supply sufficient nitrogen to show a nitrogen yield
response but they did appear to improve the early growth of sweet corn
plants.

Fourteen other field experiments were conducted with 'Vernal'
alfalfa hay applied as a sidedressing on other vegetable crOps and
field corn, but are not reported here. Sidedressed applications of
alfalfa did not increase yields or visually improve growth in these
tests. In greenhouse and controlled environmental conditions plant
responses to alfalfa additions were variable with beneficial responses
occurring more frequently on lower fertility soils.

Applications of alfalfa hay at low rates as a sidedressing do not
consistently produce beneficial responses under field conditions when
the nutritional status is conducive for plant growth. In retrospect,
studies of organic matter additions with regards to alfalfa hay may
best be studied by examining components of alfalfa on whole plant or
plant part systems and as suggested by Patrick et al. (1964), research
with microenvironments should be emphasized if organic matter additions

are made to soils.

21

Table 6. Response of 'Spring Gold' Sweet Corn to Band Applications of

Alfalfa Hay and Broadcasted Fertilizers at East Lansing.

 

 

 

 

 

 

 

 

SPLIT TREATMENT RATE FRESH WEIGHT (unhusked ears)
(kg/ha) (metric tons/ha)
MAIN PLOT N . 40 6.8
120 8.9
L.S.D. at 0.05 level 0.8
L.S.D. at 0.01 level 1.6
+ 40 8.2
SUBPLOT P205 K20
140 7.3
F RATIO N.S.
C.V. (%) 17.3
SUB-SUBPLOT ALFALFA O 7.7
100 7.7
300 8.0
F RATIO N.S

C.V. (%) 14.1

 

10.

ll.

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