"By their fruits ye shall know them" 
Fruit Characteristics Reveal Cell Factors 
fX 
Green Bartlett and Yellow Bartlett sectorial chimeras, and the tree which produced them 
The Growth is Mixed—the Problem is to Segregate; 
Greening Bud Selection Does This 
The tree and pears shown above are from the Ex¬ 
periment Station Farm at the Michigan State College, 
Lansing, Michigan. The scions came from a transi¬ 
tional limb found by Dr. V. R. Gardner, of Michigan 
State College, and Dr. E. J. Kraus, of the University 
of Chicago, when the two were working together in 
Oregon a number of years ago. The original transi¬ 
tional limb was. a mixture of Green Bartlett and Yel¬ 
low Fruited Bartlett variation. 
Ordinarily, color variations can be seen only in the 
fruit, but in this unusual case, new growth from 
vegetative buds exhibits these same color variations. 
Many different combinations of the two factors are 
to be found in this tree. One small branch is unmixed, 
segregated to normal Green Bartlett. The Yellow 
Fruited Bartlett still shows in the young twig growth 
hair-line lines of green, which indicate that segregation 
is still incomplete for the Yellow Fruited variation. 
Here we have two kinds of living tissue in one 
stem—the green tissue can produce Green Bartlett 
Pears only and the yellow can produce Yellow Fruited 
Bartlett Pears only. The growth is mixed. The prob¬ 
lem in propagating under such circumstances is to 
unmix, divide, separate and segregate. 
Selections based upon these principles of segrega¬ 
tion were made in the Summer of 1927 and are now 
growing at the Graham Experiment Station, Grand 
Rapids, Michigan, where they are under observation 
and study constantly by Greening observers. It is 
this sort of study which has made Greening Bud Selec¬ 
tion possible, practical and profitable. 
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