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THESIS FOR DEGREE OF M. 8.

ELMER WALKER BRANDES

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THE INHERITASICE OF YELLOVW-BERRY
IN WHEAT

Thesis for Degree of W.S.

Kilmer Walker Brandes
=—*

1915
THESIS
ACKNOWLECENENT
I wish to thank ‘r.Frank A.Spragce,head of the Office of
Plant Ereeding of the UWichigan Agricultural College,under
Whose supervision the investigation was carried on,for kindly

advice and assistance during the course of the work.

94238
INDEX

 

 

 

 

page
The Crop,its Culture,Value and “Naladies ee
The Yellow-berry Problem, Abnormal Anatowy = __ 7 _7
Previous Work ss ~ oe __9
‘lendelism and Explanation of Terns _ oN?
Selection,Influence of, == —=—s—s—<sM—<~—SsSsaseseseeseseseseseese
Crossing, Discussion of Results wee

 

Bibliography __ 41

cer ee ee ~ — were - we) eee ee ee

 
THE CROP
Its Culture,Value and Maladies

In view of the vast economic importance of the wheat plant
any factor which interferes with its maximum financial returns
to the growers,even to a very slight extent,is bound to be
of tremendous importance in the aggregate,provided that the
disturbing factor is universally distributed. The condition
known as "yellow-berry" is such a factor. Apparently no wheat
growing region is absolutely free from it although the amount
of damage caused by it varies considerably in different
localities. The fact that millers object to wheat in this
condition is apparent by their refusal to pay the top market
price for grain which has any considerable amount of yellow
kernels. In some cases they refuse to accept affected grain
under any consideration when healthy grain is available, the
reason given being that it affects the color and quality of
the flour. A local investigation of the attitude of the mil-
lers on this subject has disclosed the fact that they regard
the deterioration due to yellow-berry serious enough to
discount from two to ten cents per bushel,depending on the
percent of yellow-berry present,fron the price which they
would be willing to pay for healthy wheat.

Keeping these facts in mind,a short review of the wheat
industry will reveal the enormity of the financial loss
suffered by wheat growers on account of this depreciating
factor.

Wheat is a plant which is widely distributed over the civil-
ized world,and constitutes the main article of food wherever
its culture is practiced. Its history is coincident with that
of the human race. The United States leads all countries in

the production of wheat and the maximus: capacity for produc-
®

tion hes not yet been reached. Land suitable for raising this

cerial is still available and more careful methods will

increase the output from the land already in use. Figures from

the "Statisticak Abstract of the United States" indicate that

we may expect a continued increase in production. The follow-

ing table,taken from that source,and including a record of all

the crops from the year 1870 to 1910 at ten year intervals

and also the cror for 1913 shows a uniforn increase up to the

present time.

Year

1870
1880
1890
1900
1910
1913

Area
acres

18,992,591
37,986,717
36,087,154
42,495,385
45,681,000
50, 184,000

Production
bushels

235,884,700
498,549, 868
399,263,000
522,229, 505
635,121,000
763, 380, 000

Farm Value
dollars

222,766, 969
474,201,850
334,773,678
383,525,177
561,051, 000
610,122,000

Av .Yield Av.Farm
per acre Value

13.4
13.1
li.l
12.3
13.9
15.2

94.4
95.1
83.8
61.9
88.3
79.9

Estimating the loss due to yellow-berry at five percent, and

there 1s reagon to believe that it exceeds that amount,it

may be seen by consulting the above tabe that the income of

American farmers during the year 1913 was reduced by over

thirty-five million dollars. Some states suffered more heavily

than others,not only on account of the relative size of the

crops,but because the percent of yellow-berry varies in

different regions. During the last fifty years there has been

@ constant movement of the center of wheat productiog from

east to west in the United States. This has proceeded much

more rapidly than the center of population. In 1850 New York

was one of the great wheat growing states,and the Genessee

Valley was the greatest wheat growing region in the United

states. Since that time the wheat production of New York has
decreased over three million bushels,and its proportion of
the entire crop has declined from 13.1% to 1.6%,while the
four states which now produce the most wheat were,with the
exceptioyj of Ohio, still unsettled. The latter state was also
at one time the leader in wheat production,and the rich Miami
Valley succeeded the Genessee Valley as a wheat region. But
While Ohio is still a large producer of wheat,its relative
production has declined from 14.4% to 7.6%. Southern Wisconsin
and Northern Illinois was once the great wheat growing region
of the country,but this was again superceg¢ded by Minnesota
and North Dakota. For the past few years Kanses has been
producing more wheat than any other state. It seems probable
that the great plains area of western Kansas and Nebraska and
of eastern Colorado and Wyoming and perhaps northern Texas

is destined to be the next great wheat growing region. Some-
thing more than a mere following up of the center of popula-
tion may be observed from these facts. The culture of wheat
is gradually moving away from the humid regions and toward
the semi arid regions of the country,a point to which we will
presently recur.

For pirposes of comparison with yellow-berry,the damage
caused by the other important maladies of wheat will be here
considered, They may be classified as unfavorable environment
insect pests and fungus diseases. The first of these,unfavor-
able environment,would include drought;hail,wind and rain
storms;floods;fire;frosts;hot waves;excessive moisture and
unfavorable soil. Very little specific information can be found
as to the extent cf the danage caused bt unfavorable environ-

ment. Loss occures every year from one or more of these factors

but usually it is restricted to linited areas,and on account
of the conpensating distribution of favorable metecrolozical
conditioys,it is not felt much by the crop as a whole. The
average loss for a period of fifty years in France occasioned
by the most serious of these,the hailstorm,was 0.81.
There;are about one hundred species of destructive insects
which damage wheat to a greater or lesses degree. Less tham
a dozen however,occasion enough loss to be considered of very
great importance.

Perhaps the nost inportent of the destructive insects is
the Hessian Fly. In 1900 the Ohio loss was placed at over
sixteen million dollars. The Chinch Bug is next in destruct-
iveness. In years when the Chinch Bug has been unusually
severe the loss to single states has been variously estimated
at from ten to twenty million dollars. The Wheat Midge has
been known to cause the loss of from one half to two thirds
of the crop in single states. Plant Lige are thought to cause
an annual damage of about two percent in some regions. Locusts
Or grasshoppers used to devastate extersive areas,but of late
years have ceased to be of great economic imrortance. Large
porticns of their breeding grounds are now cultivated and
this restricts their multiplication. The Grain Aphis,popular-
ly known as the "Green Eug" can be found in the wheat fields
any year but it is rather erratic in its serious outbreaks.
These generally occur after a mild oren winter followed by
a cold wet spring,due to the fact that it can stand a lower
tenperature than its natural enemies. Other insect enemies
are the Wheat Straw Wern,the Joint Worm,the “heat Bulb Worm,
the Cut Worm,ssveral species of Saw Flies and the Army Worn,

the damages fron which ere local and can be controled.
While these losses seem to be enormous,it must be remembered
that the occurence of most cf the pests is epidemic,and the
interval between outbreaks is erratic. Probably the aggregate
loss occasioned by all of the destructive insects would
average less than twenty percent of the annual crop.

There are several important fungus diseases of wheat. The
Wheat Scab(Gibberella Saubbyjetii) causes a loss which is
usually light but which may reach a maximum of ninety percent
in some fields. Stinking Smut(Tibletia foetans and T.tritici)
has ruined half of the crop in Wisconsin.Loose Snut(Ustilago
tritici) is said to be responsible for the loss of over half
of the cror in North Dakota in 1905. The rusta Of wheat are
another source of loss. Two kinds are common. The Leaf Rust
(Puccinia rubigo-vera)causes a loss in North Dakota which was
estimated by Bolley to be ten percent of the crop annually.
The well knowm Stem Rust(Puccinia graminis)causes an annual
loss of over five nillion dollars in the United States.Leaf
Blight (Leptospheera tritici)and Powdery Mildew(Erisiphe gramin
is) occasionally cause slight losses in certain localities.
Vhat is true of the destructive insects in regard to the
epidemic nature of the outbreaks is alse true of the furgus
diseases.

The occurence of yellow-berry is constant and unifornly
distributed over the years. The devastations of insects and
fungi are more sensational than the losses which can be
attributed to yellow-berry, but the loss occasioned by them

if taken on the average will be found not nearly so great as

©)
Would be suspected by an examination of the foregoing figures.
It is probable that yellow-berry causes at least cone tenth
of the averaze annual loss sustained vy the wheat crop of the

United States. This tremendous loss has been overlooked
largely because it does not affeet the.size of the crop but

nerely the quality of the grain.
 

THE YELLOW-EERRY PRORLEW
Aonorm2al Anatony

Yellow-berry is a tern used to designate a condition of the
wheat kernel which gives it a spotted or uottled appearance,
due to an abrornel condition of the internal structure of the
kernel. It is most conspicucus in the tyre known as hard winter
wheat,and is varicusly terned "yellow-berry", "white-belly",
"Starchy Kernels","ealy Kernels", "piebald", "off color"etc.
The normal kernel of a hard winter wheat is more cf leas
transiucent,hard and vitreous. The spots of an affected kernel
vary in size,shape and location,often being very srall but
sometines invelving the entire kernel. These spots are seen
to be opaque when viewed in transnitted light. The gross
appearance cof an affected xernel may te compared with a cake
of clear transparent ice which has been kicked violently with
the heel or struck with some blunt instrunent,causing air
spaces to aprear between the ice crystals and nakine the area
Opaque. The nicroscopic examination of an affected berry
reveals the fact that there actually are larger and more
Nurercus alr vacucles in the cells of the affected spots than
in the healthy tissue. The spots may be near the surface,in
which case they .aresharpiy cutlined,cr they may be internal,
when they are not so conspicuous. They may occur amywhere in
the endosperm. A distinction is nade between a "scft" wheat
such as is grown in the Pacific ccast region,and a yellow-
berry kernel of a hard wheat. Sone confusion seeis to exist

setween these two in the minds of many,and some writers have
considered ther identbcal,i.e.,they have regarced the soft
wheats as merely one hundred percent yellcw-berry. That this
Opinicn is erroneous is brought out by Lycn and Keyser's
investigation(Nebraska Station Bulletin 89),on the specific
gravities of the several types of wheat. For a clearer
understanding of this experiment the chemical contents of the
kernels must te first considered. Analysis has determined the
soft wheats to be rich in starch but deficient in protein,

a condition which is also true of the yellow kernels of the
the hard type. Now the true soft(starchy)wheats are found to
posses the highest srecific grevity on account og the higher
specific gravity of the carbohydrates(starch 1.53,sugar 1.60,
cellulose 1.53),as compared with the proteids(gluten 1.397).
The hard wheats therefore,on account of their larger percent
of proteids,are lighter than the soft wheats. On the assump-
tion that the yellow-berry kernels of the hard wheats ere
identical with the soft wheats we would cxpeet to find a4
hisher specific gravity in the yellow-berries than in the
healthy kernels from the same soupwee. Eut the reverse of this
is true. Experiment has demonstrated that the yellow-berries,
notwithstanding their relatively larser starch content,are
actually lighter than the healthy berries with their larger
percent of proteins. The presence of the nhmerous air vacuoles
previously alluded to,nay be offered as an explanation for
this apparent anomaly. At any rate it is evident that ea sharp
distincticn exists between the internal structure of the soft

wheats and the yellow-berry kernels of the hard wheats.
PREVIOUS WORK

In regard to the cherical analysis of the contents of the
kernels fron a common source, Snyder,iiinnesota Station Bulletin
S5,found the difference in protein content to range from 1.6%
to 4.€7% in favor of the glutinous(healthy) kernels. That he
was dealing with what we define as yellow-berry is evident whe
he says,"In nany cases it was rossible to distinguish starchy
and glutinous seeds in the same wheat head.". He found that
dark colored,glutirous grains fron the sane source contained a
higher percent of nitrogen than the lisht colored starchy
grains. In regard to the relative value of these two types
he says,"For purpcses of nutrition wheats with the maximum
amount of protein or gluten are the nost valuable. Wheat of
Waxinun gluten content contains as much protein as average
beef,while that of mininun content contains no more than rice."

An explanation of the opaque and dead whit appearance of the
affected grains or spots is offered by Hackel,who says,"If the
alburencids so fill up the intervals between the starch grains
that the latter arrear to be exbedded in cement,the albumen
appears translucent and the fruit is called corneous,but if
the union is less intinate,there remain numerous small air
cavities,and the albumen is opaque and the fruit mealy. toth
conditions occur in the s-ne variety(wheat)and they seen. to
be occasioned by differences in climate and soil."

The yellow kernels are knewn te contain mere neisture than
the flinty kernels of the sane variety,even in grain which
has been standing for several months. This would tend to
confirn. the thecry of a more condensed accunulation of proteid

in the flinty kernels.
10

T.L.Lycn and Alvin Keyser carried on an in vestigation of te
yellow-berry problem the results of which were published in
1900 in Nebraksa Bulletin 89, An experiment to determine the
part which weathering and bleaching plays in the production
of yellow-berry was carried cn by them as foliows;half sheaves
were taken fron the field and cured in a dry room,moderately
lighted,and the other halves were allowed to renain in the
field from July 10 until Ausust 21. The bundles were then
threshed and separated into two portions,"yellow-berry" and
"horny red", The bundle kept in the dry dark rocn had only
twenty-five percent of yellcw-berry,while the exposed bundle
had 97.6 percent of yellow-berry.

Cuttings were made of the seme wheat at intervals of fcur
days and it was discovered that the percent of yellow-berry
increased as the grain becane riper. That there is a definate
relation vetween the percent of yellow-berry and the character
of the season,insofar as the latter affects the date of
ripening was determined by the amount of yellow-berry in the
crops of different seasons. The amcunt of yellow-berry
increases with the lateness of ripening,and it was further
indiceted that crops of large yield and low nitrogen content
contained mcre yellow-berry than crors of the orposite kind.
Analysis of samples in every case substantiated the millers
statements that the horny red type contained more gluten than
the yellow-berry wheat(i.e.it had a larger nitrogen content).
The authors attribute the presence of yellow-berry in wheat

tc failure te stack sheeves,and base their suggestions for
11

alleviating the condition on these conclusions. They recommend
early cutting and prompt stacking.

Professcrs Roberts and Freeman of the Kansas Experinent
Station, bulletin 156,1°908,attack the problem fron a different
standpoint and arrive at entirely different canclusions.

In regard to climatic influence they draw attention to the
fact that it has long been known that in cocl moist climates,
such as the naritine regions of western Europe and our own
north Pacific coast,the wheats there grown have larger grains,
are softer and lewer in percent of proteid nitrogen than the
wheats grown in continental areas such as the interior of
Russia,the Falkan States,ifuncary and the central western
states of our own country. In their discthssion of the internal
structure of the wheat kernel they quote Lyon and Keyser as
follows,"The protoplasmic network of the cells in the sections
fron the very horny kernels showed only an occasional vacuole;
sections fron the narkedly yellow kernels showed very much m
more numerous and larger vacucles,neasuring on the average
less than 0.001 willimeter. Mediun yellow-berries had fewer
and smaller vacuoles than the markedly yellow kernels,"

Their investigation of temperature and vegetative period in
relation to the percent of yellow-berry would seen to indicate
that ripens later and at a higher mean temperature has the
least amount of yeliow-berry. These investigators are the
first to discuss the possibility of yellow-berry being an
hereditary tendency. In regard to this possibility the authors
consider the elinination of yellow-berry by the method of plah
plant breeding as wholly depentent upon the extent to which
yellow terry is distinctly a heritable product,and not a

fluctuatin: variation common to all the strains cf glutinous
wheats when grown under certain seasonal conditions. From the
data gathered it was found that the nwiniinum anount of yellow-
berry in the groups studied in 1907 cane from those groups
showing the minimum amount in 1906. This points to a certain
desree of actual inheritanve of the yellow-terry tendency.
A study of pedigreed wheats in 1906 and their progeny in 1907
showed a ccrrelation in the agount of yellow-berry., which coulda
coe ascribed only to an inheritance of the condition on the
part of the individual piants. Their deductions are sunned up
in the following words;"In view of the fact that but one head
from each plant of the pedizree parent stocks had to furnish
the grains upon which an estinate of the percentaze yield of
yellow-berry in the plants as a whole was tased,the result
is surprisingly confirmatcry of our hypothesis that the yellow
berry is a 'tendency' which finds expression ir certain strains
or races more markedly than in others and is heritabie",

G.W.Shaw and E.t.Walters,California Station Bulletin
have brought out some interesting facts in regard to the rela-
tion of soil and climate to the gluten content of wheat,and
to the percent of "starchy kernels". Realizing that niost of
the earlier work had been done in the presence of two variables
soil and climate,they set abcut to bring two types of soil
under identical climatic conditions. This was accomplished by
shipping a sufficient amount of Kansas soil in tags to the
test plat in California. The chemical and mechanical analyses
of the soils were determined and also the analysis of the
wheats grown. The tabulated results do not show that the soil
had any marked effect on the sluten content of the wheat.

They found that the soil nitrosen content had little if any

Girect influence on the nitrozen content of the crop,but that
13

some Climatic factor conpletely overshadowed the soil factor.

This conclusion is in direct opposition to the deductions
mace by Headon,Colorade Station Eulletin 205,who states that
the elements of the soil is the one and only controlling factor
in the production of yellow-berries. Shaw and Walters go
farther in stating that it appears as though the nitrogen
content of the orisinal seed,when grown elsewhere than in a
Climate within which it has been acclimated has little or no
inflvence on its progeny,and that even if it be acclimated,
still sone seasonal ciimatic factor is sufficient either to
lower the nitrogen content of a hich gluten wheat,or raise the
nitregen content of a low gluten original. Another interesting
result of the experiment was the presence of more "starchy
berries"(8%) in the check plat than in the plat where the soil
had been disturbed,i.e.the soil had been removed for a depth
of three feet and the same soil replaced to make the
conditions the same as for the imported soil. The grain from
this disturbe2 soil plat was of high milling quality and
contained no"starchy berries". No reason was assigned for this
very interesting developement.

Neadon, Wm.P.,Col.Sta.Bul.205 states,"I do not think that the
there can be any question of the identity of the affection of
our wheats with that of Kansaes,iWwebraska or North Dakota, and
alnost no queation but that the starchy,opaque wheats of
California and the Pacific coastdstates,in general,are identi-
cal in their character with extreme cases of yellow-berry in
Colorado anid have the sane cause." This statement is not at al
in harnony with the results of the experiment previously cited

concerning the difference in nicroscopic anatony and specific
14

gravity between these two wheats. There is reason to believe
that there is a sharp distinction between the internal
structure of a true starchy wheat,and that of a yellow-berry
xKernei of a hard glutinous wheat,and that yellow-berry may
occur in the true starchy wheats just as it does in the hard
wheats,but is not so noticeable by a superficial exarination.
Dr.iieadon apparently bases his opinion upon the macroscopic
aypearance of tnese two tyres of wheat,which are very

Sinilar as far as their gross anatomy is concerned. The
investization which Dr.Headon conducted during the years of
1913 and 1914 included thirty-six experinents each year, the
the resuits cf but twelve each year being publisneda for the
sake of brevity. In 1913 he planted twelve rlats of wheat,
four plats of each of the three varieties tested. The first
plot of each variety was treated with nitrogen fertilizer

at the rate of eighty rounds to the acre,the second nlot with
soluble rhosphcorus,forty pounds per acre,the third piot with
potassiun,one hundred and fifty reunds rer acre and the fourth
wlot of each variety wes zrown as 2a check. The foilowing year

the experiment was repeated,using the same plots for the

Cb

respective varieties,and usins the 1913 crop for seed in 1914.

The results may be best shown in tabular form.
15

Percentage of Yellow-verry in Crops of 1913 and 1914

Variety Fertilizer tyelleow-berry “yellow-berry

in 1913 in 1914

Tefiance ~itrogen none none
Phosphorus 1C .0 50.9

Potassiun 30.0 63,0

Check et .0 36.0

Red Fife Titrogen none et 0
Phosphorus 24.0 97 .0

Potassiuni 42.0 98,0

Check 31.0 96.0

subanka ditrogen none 23.0
Phosphorus 35.0 94.0

Potassiun 37.0 96.0

Check 31.0 97.0

In discussing these results Dr.Headon says,"The only causes
heretofore assigned for the appearance of this affection in
wheat are over-riveness of the grain,standing too long ih the
shock, exposure to the action of moisture,air and sunshine,a
heritavle 'tendency',the action of fungi and the climatic and
weather conditions, -~ no one of which can be considered as the
cause in our case.*** The question of a tendency which is
heritable is fully set aside by the fact that we can,fron the
sar.e lot cf seed,under identical conditions of climate, grow
crops affected with or free from yellow-berry.*** We can see
that in every case,the application of nitrogen,which was in
the forr. of sodic nitrate, greatly reduced the aniount of yellow
berry,in sone cases preventirg it altogether." Again in the
surnmary of this bulletin he says,"Yellow-berry can be very
much lessened or entirely prevented by the application of a
sufficient amount cf available nitrogen. Yellow-berry can be
greatly intensified or increased by the application of avail-

able potassium."
These resuits ure very interesting and show beyond a doubt
that the soil elements influence the evident or rerceptible
amount of yellow-berry to a large extent.

The couwplicated,and in many cases contradictory results
secured in this line of investigation have resulted ina
wide divergence of opinion as to the factors which influence
this condition of the wheat kernel. Some consider it the

result cf a3ezeneration in the variety,otherg telieve it to

be due to soii ana cli:natic conditions,or regard it as the
consequence of growing the sane seea year after year,wiile

still cthers attrioute it to the condition of the crop at

\

the time of harvesting. Tne possivility of its being a char-
acter inherent in the individual has been considered and it is
the aprarent logic of this latter solution, resulting fron
observations covering a period of years,that leai to th

inception cf the present investigation.
17

monwloblsd AND EXPLAUATICN ©

ry

TLRS

Before entering into tne technical details of this probdlem
it will be well to voriefly sunmarize the rules governing the
more important phases of heredity,especially those which have
@ direct bearing on dominance and segregation. The most signal
achievements in this field were accomplished in an unostenta-
tious manner by Greszor Johann wendel,and Austrian monk,who
in the privacy of hidé cloister garden carried on experiments
with the com:.on garden pea which result#d in his publishing
in 1866 the first fundamental contrivdution to the laws which
govern the inheritance of unit characters. itils work consisted
in tne hyoridizaticn of the several varieties of Pisun,the
two parents of which were selected on account of differences
in the same unit characters,such as white or colored flowers,
green or yellow endosperm,elongated or snorterned stens etc.
The progeny of these crosses,termed by “iendel the first filial
(F, ) generation,were carefully watched,and a careful record
kept of the proportions in which the unit characters appeared
in the offspring. He discovered that in most cases one of the
two opposing characters was dominant while the other was reces
sive,i.e. the character in the offspring was not intermediate
between those of the two parents,but was to all appearances
identical with that of the dominant parent. In the next gener-
ation newever,it was found that the erogeny were not all like
the dominant grandparent, >but had segregated into the two types
Which had been mated together in the first place. The most

remarkable part was that they had segragated according to
18

af

definate numerical ratios in every experinent Which Nendel
perfcrmed and these results have given rise to what is known
as "Mendel's Law", It may be briefly fornulated as follows;
“nen two organisms that ure unlike in resvect to any unit
character are crossed,all of the offspring,coupesing the Fy
generation will resemble one of the parents identically in
their somatic constitution, but will differ in their germinal
constitution. In the Fo zeneration,however ther will be 85%
ef the offspring like the dominant grandparent,25% like the
recessive grandparent and 5Cy like the rarents,which,it will
be remembered resenbled the dominant grandparent. Since the
first and last of these groups are to all appearances iden-
tical,the apparent ratio will be three to one of doninants
and recessives respectively. ‘iendel's original experiment
will serve to illustrate the actual working cf this law.
Tall and dwarf peas were crossed and the seeds from this unton
planted. They gave rise to tall plants only. The seeds fron
this crop were planted,and the offspring were observed to be
in the proportion of 75% of talls to 25% of dwarfs. Mendel

explains this result diazranatically as follows;

(Tall) oN CN
Tt F

1
TT Tt TEE Fo

The unit characters or genes represented by T and t are
double because every sexual individual is made up cf contribu-
tions from each of the two parents. When these contributions

are alike,as is the case in both parents here shown,the
condition is known as homozygous. If they are unlike,as is
the case in the Fy generation the condition is known as

heterozygous. The phenomena of segregation arises from the
uniog of two of these heterozugous individuals. It may be

represented graphically in this manner;

 

 

T t
T TT Tt
t Tt tt

 

 

 

 

Every possible combination of the gametes of the male and
female parent is shown in the proportion in which they would
occur no matter what numbers were involved,1l TT:2Tt:l tt.
This is due to the law of chance which alone governs the
union of pollen grain and ovule.

When the homozygous individuals breed, their offspring will
come true,but when heterozygous individuals breed their
offspring will segregate in exactly the same manner as was
shown for the Fo generation. Since the promulgation of the
"Presence and Absence Hypothesis",which has been generally
accepted,the terms duplex,simplex and nulliplex have replaced
homozygote and heterozygote. According to this hypothesis a
character determiner (gene) is either present or absent in
an individual. If two germ cells possessing the character for
tallness unite,they rroduce a duplex(TT),if one parent has
the character and the other has not they produce a simplex
(Tt),if neither rarent has the character they produce a

nulliplex(tt).
An allelomorph is the reaction of a gene with its absence
in a Mendelian distributbon. Yellow-berry and absence of
Yellow-berry might be assumed to be the allelomorphic pair
in the following discussion.

Autogamy (self marriage) is a term used in plant breeding
to designate self fertilization in plants. The wheat plant is
autogamous.

A population is all the decendents of a single seed,whether
they are genotypically alixe or not.

Progeny usually refers to the immediate offspring of a plant
Od

SELECTION

It has been demonstrated that the selection of kernels free
from spots for use in propogating has not resulted in estab-
lishing strains which have no yellow-berry. For years the
idichigan Agricultural Experiment Station has culled the
"off colors" and planted nothing but kernels of the ideal type
and yet the progeny of these healthy kernels contained varying
amounts of yellow-berry. This disproves the theory that the
spotted condition is dominant,for in that case the healthy
kernels would be recessive,consequently nulliplex,and would
breed true,under natural conditions because wheat is a self
fertilized rlant. If the healthy condition were dominant,
considering healthy and yellow-berry as the allelomorphic
pair,we would expect to find in autogamy under no selection,
a slight preponderance of healthy berries. The following chart
in which healthy berries are represented by the duplex HH,
and simplex sih,and the yellow-berries by the nulliplez hh,

will show the expected rroportions.

 

 

CHART I
Generation 2 3 4 5 6 7 8 9 10 n
HH 1 3 7 #15 31 $83 187 255 511 gn-Il—}
Hh 2 8 8 8@ 8 82 8 8 8 2
bh 1 3 #7 #15 31 63.187 355 511 gn-l—})
summation 4 8 16 38 64 128 256 512 1624 @2n

At the end of ten generations the proportion would be 513
to 511 of healthy to yellow-bcrries and at the end of n
generations the difference would be practically negligible.
This approximate proportion is net with in many pure lines
which have been bred with no selection for a number of

eenerations at this station.
Assuming the same condition of dominance,if mass selection
were practiced we would expect the duplexes and simplexes
(healthy) to gain an overwheluing preporiderance over the

nulliplexes(yellow-berry)in a few generations according to the

 

 

 

 

 

formula;
CHART II
Generation o 3 4 5 6 7 8 9 10 n
_ HH 1 3 7 15 31 63187 255 511 jgn-l~j
Hh 2 8 2 8 8 8 8 8 2 8B
hh 1 12 322221 2212 ~=«2~@«21~«21
Summation 4 6 10 #138 34 62 130 258 514 °&1«°gn-I 42

In the experirents conducted at this station,mass selection
has resulted in no such preponderance of healthy berries, so
it would seem that the healthy condition is not at least a
Bimple dominant of an allelomorphic pair. At the same time it
does not disprove that yellow-berry is inherited according to
some definate iendelian ratio,as there are many exceptions to
the law of dominance. The mathematical precision whth which
dominance wes found to act by Mendel in his experinents with
the garden pea has been found to breax down in some cases of
other organisms. Imperfect dominance,as in the case of the
blue Andalusian fowl,reversed doninance,illustrated by Lang's
experinents with srails(Helix),in which snails with yellow
shells were found to ve sometimes dominant over those with red
shells althougn the reverse of this was generally the case,
the phenomena of potency and blending inheritance are sone of
the factors which are exceptions to the general rule of simple
dominance.

Selection has resulted in strains which vary greatly in the
0:
GI

amount of yellow-berry present. Red Rock,a variety originated
at this station is singularly free fron yellow-berry,while
other strains have been dropred altogether on account of the
large percentage of affected kernels. These wheats were all
grown under the same environmental conditions. This would
tend to show that the amount of yellow-berry is influenced by
other than environmental factors.

Until last fall no yellow kernels were planted,all of the
selecticns being made from the ideal type of kernel,but at
that tine yellow-berries as well as healthy berries were
planted in an attempt to discover the prorortions of healthy
and yellow kernels reg’ulting fron yellow-berry seed. These
results of course will be very important but ugfortunately
they cannot arpeur in this paper,which must be rresented befor

tne crop is hervested.
24

CROSSING

The work upon which the opinions of the present paper are
based was undertaken by the Experiment Station of the Michigan
Agricultural College,not as a study of the inheritance of
yellow-berry,but for the general inprovenent of Michigan
wheat. This was started in ]9}2 with the crossing of several
different types of wheat the progeny of which were planted the
following year and individual records kept of every plant.
This method has been pursued until the present time at which
the progeny of those of the original crosses that were re-
tained aniounts to about seven hundred and fifty thousand seeds.
During the course of this work it was observed that yellow-
berry occured very unevenly in different individuals grown un-
der identical conditions of soil and climate. Until last year
no accurate counts were made of the proportions in which
yellow-berry occure: in the individual plants. The 1914 crop
was harvested and stored,as in previous years,in manilla
paper envelores,each envelope containing the seeds from a
single plant,whose ancestry could be traced back three years.
The plants were all numbered according to the systemmin use
by the plant breeding office of the farm crops department.
The harvest fro. each plant is placed in an envelope and an
entry nade in the record book,noting all the characteristics
under consideration of the plant in question. Individual
populations were grown in separate plots which measured
approxinately three by five feet. This fact is is:portant in
what is tc follow as it, indicates that the plants were in close
enougn proximity to eliminate any differences due to
environmental influence,such as waves of soil fertility,

une
uneven distribution of fertilizer,moisture and so forth.

A hereditary tendency has ceen offered as a pessible solu-
tion of the yellow-cerry problen,and observations by
ur.Frank Spragg,head of the plant breeding office of the
College tended to confirm this theory. Consequently the
present work was undertaken under ‘ir.Sprageg's direction in
the hore that it night contritute to the xnowlese of this
condition of wheat,which has been such a serious provlen to
the inprovers of grain during the past few years.A study of
the various types of Nichigan wheats revealed the fact that
none of then are free from yellow-berry,and niost of them are
affected to an alarming extent. As before stated,the extent
to which an individual may be affected ranges from a single
minute spot,which may be located anywhere in the interior of
the grain to a condition whereby the entire endosperm is
involved.The spots are conspicuous and can be readily detected
when located near the perirhery,but it is extremely difficult
to detect an affetted berry when the spot is situated near the
center of the grain. Owing to this fact it is easy for error
to creep in when separating the grains by inspection into
yellow-berry and healthy classes. It is desireable for the
operatcr to section a number of rains of the various classes
in order to become thourouchly familiar with the correlation
between internal structure and outside aprearance,as it
Would be impossible to section every kernel on account of the
numbers involved and becouse the seed would of course be
destroyed and the experiment terminated. Thus it may be seen

that there will be nume@rous individuals of uncertain
Classification and unavoidable error will enter to a slight
extent. It is hoped however that this error is sore or less
compensating ani that the proportions will be found quite
accurate. On account of the persistence whth which all the
affected grains of scone progenies tented toward partial
yellow-berry while others tended toward complete yellow-berry
it was decided to separate the seeds of each progeny into
three classes,terned for the sake of convenience, healthy
berries,spotted berries and yellow-berries. Those grains
which were apparently unaffected were put into the healthy
class,those which were entirely affected were put into the
yellow-berry class and those which were internediate between
the two extremes,i.e.those which exhibited an affected area
ranging from a minute spot to almost total yellow-berry were
put into the spotted class.The progeny of each plant was
examined separately and the seeds sorted into these three clas
Classes. The progenies wer: found to have segregated into

all three classes in most csases8,but some were entirely healthy
some entirely yellow-berry and sone had segregated into any
two of the three classes.Apparentiy neither the elements of
the soil nor the climatic conditions were the controlling
factors because there could be found plants included in the
small area of a test plat exhibiting a most startling range
in the percent of yellow-berry. It might be argued that an
unequal distribution of fertilizer or a cow dropping here

and there might account for these differences, but the root

system of a wheat plant is sufficiently large to insure
ao?

individuals,whose maximum distance apart is fwom three to five
feet(the size of the plot)feeding on the same soil elements.
An examination of some cf the seed counds of the individual
plants grown in the same plots,taken at random from the note
book, which is much too volumincus to reproduce here in full
show that these differences were not occasional,but frequent
and uniformly distributed.
TABLE I
Results of Count in Plot II of 1914

hea ee Pearl Grains
Plant No. Healthy Spotte ellow Ttlealthy Spotted Vellow>

40201 36 74 33
40208 7 164
40203 14 g 87
40204 7 13 84
40205 23 70 34
48206 105

40207 28 10

40208 73
40209 97 25 27
40210 154 45 30
40211 94 66 26
40212 57 37

40213 3 11 66
40214 56 g

40215 26

40216 4 3 32
40217 48 85 44

402618 15 29 1a
Red .«._ Grains _ _Pearl . Grains
Plant No. Healthy Spotted Yellow “Healthy Spotted Yellow

40219 89 72 21

40220 88 2

40231 74 16 6
40222 13 71 114

40223 77 3

40224 58

40225 4 9 19

40226 36 13

40287 4 269

40228 13 33 63

40229 27 81 42

40230 50 66 25

40231 10 _B? 38

40232 25 44 13

40233 24 293

40234 21

40235 6 19 82

402836 39 22 33
40238 6 33 104

40238 33

40239 34 14 43

40240 60 3

40241 26 Bl 54

40242 139

40243 190 4

40244 137 20 41

40245 105 — 13

 
Red Pearl
r —T~ “ ? “
Plant no. tealthy Spotted Yellow Uealthy Spotted Yeliow

 

40246 3a

40247 2 3 132
40248 16 34 oh
40249 52

40250 23 "35167
40251 g 12 «198
40258 63 32 136
40253 g 10 17
40254 9 41 45
40255 7 17 48
40256 167 33 aS
40257 196
40258 4g 1

40259 1c]

40260 88

40261 19 1
40262 74

40263 30 39 51
40264 7 32 72
40265 49 26 16
40266 44
40267 44
40268 4 4 34
40269 5 28 126
40270 29 5 124
40371 6 31 240
40272 43

40273 62 598 oA
 

Red Pearl
Plant No. Healthy Spotted Yellow “Healthy Spotted Yellow
40274 25 30 124
40275 98 46 136
TOtal 1464 1441] BEL
RATIO - 09799 : 1.0058 : 2.014
EAPHCTEE RATIO - 1.0000 : 1.0000 : 8.C0C

This populatiob represents the Fo generation of a cross
between wheats number 60101 and number 6C0801,pearl and red
wheats respectively. The totals given are the totals of those
progenies which segregated into all three classes. They can
be seen to have segregated in regard to color also,but we are
not concerned with that fact beyond its proving the strain to
be a true hybrid. The term "expected ratio" 1s used advisedly.
It is not neanf$ to convey that an undivided ratio of 1:1: 06
will finally be found correct,but merely is used because the
tendency of the material seems to be in that direction,and it
will serve for purposes of discussion. This population is seen
to come very close to this expected ratio. The difference
between spotted and complete yellow-berry may be merely
quantitative,so that these two groups can be lumped together
in which the ratio would be one to three of healthy and
yellow-berries. They were separated originally on the assunp*
tion that the spotted condition was intermediate between
healthy and conplete yellow kernels. Assuming that this is
& normal .iendelian sezgregation,it would indigate that the
yellow-berry condition is dominant cver the healthy grain.

Our present knowlege of the phenor.ena of segregation, however,
dees not uphoid this assunption,since it has been shown that
the healthy berries do not breed true(p.2l)as they would if

they were nulliplex,
There is absolutely no uniformity in the amount of yellow-
berry to ove found in the individual plants to indicate that
it is the result of soil elenents or climatic conditions
alone. On the other hand the great variation in the percent
of yellow-berry seens to point out very forcibly that it is
due to differences in the individual germ cells.

The following tables are extracts taken at random from the
data of various popuiations,which,for the sake of brevity
will not be given in full.

TABLE II
Result of Count in Plot III of 1914

 

——— RED PEARL _
Plant to. tealthy Spotted Yellow “Healthy Spotted Yellow
403001 S 18 13%
4030Ce 35 49 161
403003 li 11 176
403004 1 6 26
403005 42 38 43
403CC6 2 28 179
403007 13 13 126
403C0C8 5 S 26
403009 60 25 193
403010 ' 14 18 Lit .
403063 7 200
403064 72
403066 131
40306E: -~ 142 39 65
4C3C67 . 187 .
403077 26 1
4C30EC 159

 
38

Red Pearl
a Ne tea ame eee eae a
Plant .io. sealthy Spotted Yellow Healthy Spotted Yellow

 

 

 

403081 1 118
* * *
403109 32 3 3
403116 35 46 87
4031lil 28
4C31l1é 100 48 51
403113 15 4 OOo |
Total 2548 1755 10546

RATIO - .7733 : .46C4 : 8.7803
variation in
The extreme,anount of yellow-berry is exhibited by the indi-
vidual plants of this population as was the case in the
previous one. This was the result of a cross between the
Same two wheats that were the parents of the preceeding.
TABLE III

Fesult ef Count in Plot IV of 1914

        

BD PEAR

Plant sic. iealthy crotte ellow ‘siealthy Spotted Yellow
404033 118 31 9
404034 127 31 3
404035 1 4 1C6
40403¢ 62
404037 1 62
404032 16 52 83
4C4039 44 70 68
404040 , 181
404041 1 48
404042 168

m ® *
+04187 104
4041868 150 112 17

404165 6 Lol 10S
AS P.
—me —_ $e) Fanaa
Plant Ne. Healthy Spotted Yellow TUealthy Spotted Yellow

 

 

 

404190 3 136 125
404161 4 30 7
404192 2 18 30
404193 2 12 80
404154 - 3 159
404195 46
404196 3 51 50.
Total 3657 309 B5o9
RATIO - .8541 : 1.9485 : 3.0974

The ratio here has a tendency toward the expected ratio of
one to one to two. Here afain the cross was between the same
wheatgas in the yrevious populations. The abrupt change from
all healthy progenies to all Bellow progenies in consecutive
plants is again illustrated.

TAELE IV
Result cof Count in Plot VII of 1914

R. RP
Plant ilo. Healtny spotted Yellow “Healthy Spotted Yellow

 

407032 117 5S
407033 129
407034. 42 9 3 1
407035 111 1 1
407036 186
407037 168
407038 191
* b a

407081 2 51 50
497082 3 38-150

Total 977 1540. 2917

RATIO - 270205 ?: 1.136 : 6.151
54

This was a cross between wheats £135C2 and 60101,both of
which were pearle.The progenies which did not segregate ran
pretty uniforsly toward yellow-berry.It is interesting to note
that two of the plants in this series produced red graine
although both parents were supposedly rure pearls. This fact
is the nore inexriicable on account of the fact that red was
clearly shown to be the doninant in the previcus crosses. Of
course there is always the rpossidliity that they nay be
nutaticns,

TABLE VI
Result of the Count in Plot XIV of 1914

a ee .
Plant No. Jealthy Spotted Yellow Healthy Spotted Yellow

 

41401 115 65 50
41402 7 20 229

41403 138 20

&14CA 64 7 31

41405 37 10 83
41406 190 67 90

41407 210 21 60

41468 10 15 B62

4140¢ 13 19 171

41410 3E0 23 31

41411 170 13 44

41412 _ 4 271

Total 1638 - 360 2071

PATIO - 1.633 : .3539 : 2.C36
This was a cross tetween wheats 03417 and SSzZO0l,rearl ana

red respectively. There were only twenty three plants in the
prorulation,hardly enough to base any deductions upon. Every
plant segregated into healthy and yellow berry grains and in
nost of then all three classes were represented.
TABLE VI
Result of Count in Plat &V of 1914

R. p
Plant No. ‘tealthy Spotted Yellow Tealthy Spotted Yellow

 

 

 

415C1 37 5 97

41503a 128 2 5

41503 169 2 6

41504 45 1528

415C5 47 3 e

4150 125 29

41507 115 2 7

41572 eo? 73 73

41503 34 E3 “50

41510 5 10 246

41511 152 6 14

41512 46 25 160

41513 o7 SO 126

41514 wo 59 150 .
41520 238

41521 | 39 72 110
41526 125 4° 1Oo

41523 1s 663

Total 798 450 1340 —

RATIO - 1.623 : .7635 : 1.3993

This population was a cross between the same wheats as the
preceeding. The ratic here aprrcaches the exrectei one to one
to two pretty closely.
TASLE VII
Result of Count in Plot AVIII of i914

PrP
nn lthy Guatten Valiayn
icalthy Spotted Yellow

 

 

Plant “io
41601 75 75 77
418C2 65 3 3
41803 141 ES 40
4]€C4 64 1¢ 59
4465C5 OS 8 12
41605 30 1C¢ 10
418C7 S 64 59
41ECS 35 1
4£1ECS S1 61 46
41810 518 3 1
41611 BOG 6 c
41612 oS o 2
41€13 S6 oS 40
41814 37 1
41815 LES C5 S5
41616 13¢ 5 . 6 .
41€136 5 7 159
416137 164 34 1
41813 _ 65  _._ 7 E92
Total 4156 SSéC 4562
RATIO - 1.497 3: 1,05 1.453

 
ov

The two parents here were 6C101,4 pearl wheat and 95401,
a red wheat. fs far as variation in the individual plants
is concerred it is not very different from the other popu-
lations cited,
TABLE VIII

Result cf @ount in Plot XIA of 1914

 

 

 

P.
Plant No. realthy Spotted Yellow

419117 56 9 1
415118 140 34 168
419112 7 40 165
416150 8 59 40
419131 102 45 305
41$122 19 12 3 10 29 85
415123 70 75 71
419134 124
419125 2 30
419126 50 18 40
4191327 1 1 29
419128 102 2
419129 15 30 324
415130 40 38 13¢
416131 117 34 Ge
419132 . 8 4 156
19133 40 O5 102
419134 60 16 200
419135 45 35 65
419136 39 70 403

419137 29 £2 350

 
38
TAELE VIII(contirved)
Total 7587 SESS 2244
RATIO - 1.4726 : .695 : 1.335

This population and the preceeding,both of which came from
the cross 60101795201 do not approach the expected ratio of
three to one very closely. However they show the same variae-
tion in percent of yellcw-berry in adjacent plants which has
been characteristic of all cf the pepulaticns. It is very
evident that sone innate elernent in the individual rlant is
responsible for these variations. It would te manifestly
wrong,however,in the face of the evidence of other investiga-
tors to ascribe the presence of yellcw-berry th inheritance
unreservadely.

Judging by the results of these other investigations it
Would seen. probable that certain factors,such as soil and
clinate,influence the degree to which the characteristic
beccnes evident. However it is not overstepping the bounds
justified by our evicence to assert that the fundamental
factor is some unit character within the germ cell. That is,
it is a character which is latent,and under certain environ-
mental conditicns may be entirely suppressed,but under other
conditions may become very noticeable. The conditions which
seer to favor the suppression of yellow-berry are dry,short
crowing seasons,(Lyon and Keyser, Neb.fta.Pul.e9.) and an
excess cf nitrogen in the soil, (Headon,Col.€ta.£ul.s05.),
While the environnental influences which bring about the

Opposite condition are long moist growing seasons and an
3g

excess of potessiun fertilizer. Just how these factors exert
their influence in regulating the perceptible amount of yellow
berry is a proble:: fer the plant physiologist.

At the present stase cf this investigaticn no final state-
ment can be nade of the proportions into which the different
types or classes of yellow-terry segregate. A summation of
all of the segregating rerulaticns shows the healthy berries
and yellow-berries to be in the proportion of 28.62% to 71.38"
which is very nearly a “Verndelian ratio of cne to three, but
on account cf the erratic behavior of some of the individual
porulations the significance of this is questionable. It is
provable that yellow-berry is not a sinple Mendelian character
or if it is,there are certain influences which may obscure
the condition and make the results difficult of interpretation.
Coupled with these outside influences are other considerations
such as the exceptions to the general rule of dominance,
illustrated by imperfect doninance,tlending inheritance,
reversed douinance,the necessity for nore than one factor for
the production of yellow-berry or.abdsence of yellow-berry and
so forth which would confuse our results with the available
data. Only the data of succeeding generations can,with any
certainty,estarlish the establish the exact rrorortions in
which yellow-berry is transnitted. The present work is,at best
merely a contributicn to cur knewlege of the phenomena
attending the inheritance of yellow-berry,which is as yet

an unsolved problem. The object of this paper is to show that
40

there is sonething nore than environmental factors concerned
in its prevalence,and the evidence points strongly to the
fact that yellow-berry is due fundamentally to some innate

character in the germ ccll,and is heritable.
12064.

1504,

1905.

1906.

1909.

EIBLIOGRAPHY
Johannsen
Sone Investigations on the Relation of Size of Grain
to the Nitrogen Content in Wheat,
Ex. Sta.Rec.18,p.356
Influence of Climate and Soil on Conposition and
-arxket Qualities cf Wheat.
Tenn.Sta.cul.,Vol.16,"%0.4,¢p.179-188.
onyder,
Glutinous and Starchy Crains
winn.Sta.2ul.€5,rr.179 -1EEe
Eolley
Study cf Elevator Canples of Wheat.
x.eD.Sta.Ful.,Rept.1904,pr.44-51.
Lyon and Xeyser
tature and Causes of Yellow Eerry
Neo. ota. £ul.89,r7.23-35.
Inproving the Quality of Wheat
Lyon
BeP.I.,bul.78,7r.160.
noberts and Freenian

The Yellow Berry Problem in Kansas

Yellow Eerry in Hard Winter Wheat
Farmers Bulletin 365,pr.317-32c0.
iieadon

a
The Cause and Prevention of Yellew-bverry
Col. Sta. Bul]. 205.
ROGM USE ONLY

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