Lindstrom: Chlorophyll Factors of Maize 
EFFECT OF UNFAVORABLE FACTORS 
But what of the distribution of the 
unfavorable factors in the chromo- 
somes? If we can demonstrate that 
many factors causing a reduction in 
the vigor of the maize plant are distrib- 
uted in many different chromosomes, 
it would add positive evidence to the 
present theory on the effects of in- 
breeding. It is the purpose of this 
paper to point out the distribution of 
some such unfavorable factors, espe- 
cially those concerned with the devel- 
opment of chlorophyll. 
Chlorophyll abnormalities are very 
prevalent in all types of corn. They 
have been observed in dent, flint, 
sweet, pop and flour corn. These ab- 
normalities vary from a total absence 
of all pigment (shown in pure white or 
albino. seedlings) to shades of light 
green that are almost indistinguishable 
from normal green. An _ intensive 
search for such chlorophyll defects sur- 
prises one by their frequent occurrence. _ 
The presence of any one of these reces- 
sive chlorophyll abnormalities in a 
commercial strain of corn is a serious 
factor in reducing yield. 
At least eight factors that influence 
the inheritance of chlorophyll have al- 
ready been reported. These are the 
seedling factors producing white, vir- 
escent-white, and yellow seedlings and 
the mature plant factors producing 
golden, green-striped, Japonica (both 
green-white and green-yellow striped), 
fine-striped and lineate plants. In ad- 
dition there are three new factors, still 
under investigation, making a total of 
eleven factors governing the formation 
and expression of chlorophyll in maize. 
It must not be supposed that these 
eleven factors comprise most of the 
actual number concerned in chloro- 
phyll inheritance. They only repre- 
sent the ones that are most easily 
handled. There are certainly many 
others, especially those which produce 
the lighter shades of green so often ob- 
served in different types of maize. 
But these are very difficult to work 
2 Lindstrom, E. W. Chlorophyll inheritance in maize. 
13:1-68. 1918. 
271 
with, since their expression is greatly 
modified by external conditions. Such 
factors also would influence the vigor 
and yield of the plant. It is to be con- 
fidently expected that their inheritance 
will prove to be similar to that of the 
eleven factors already known. 
In a previous publication? it has 
been shown that many of the chloro- 
phyll factors are inherited indepen- 
dently of each other. It has also been 
shown that two of them (I, yellow seed- 
lings and g, golden plants) are linked in 
inheritance. 
Further evidence is now presented 
to show that some of these same chlo- 
rophyll factors are inherited indepen- 
dently of still other factors. 
RELATION OF WHITE (ALBINO) SEED- 
LINGS TO ALEURONE AND ENDO- 
SPERM FACTORS 
A sweet corn with colored aleurone, 
of the composition 14ACCP,P,RR 
Su Sy WW, was pollinated by a plant 
with starchy, colorless endosperm, het- 
erozygous for albino seedlings (#14 ACC 
P,P, rr Sy Sy Ww). The F, endo- 
sperm was starchy and had purple 
aleurone color in all of the grains 
The F, plants were all normal green. 
Ten F, plants were self-pollinated. 
The F, grains on all showed a distinct 
9:3:3:1 ratio of purple starchy, purple 
sugary, colorless starchy and colorless 
sugary grains, respectively. These 
four types of seed from each ear were 
planted separately. Among the ten 
F, seedling progenies, six produced 
nothing but green seedlings, while four 
showed a sharp segregation into green 
and white seedlings. The expectation 
in this respect was of course five and ° 
five. 
The four F, progenies that showed 
segr gation are presented in Table I. 
It will be noted that three of the 
four seedling progenies are grouped 
together while the fourth (2959) has 
been segregated and totalled sepa- 
rately. This was done because 2959 
was a poorly developed ear that showed 
Cornell Univ. Agr. Exp. Sta. Memoir 
