YELLOW-BERRY IN HARD WINTER WHEAT 



By Herbert F. Roberts 

 Department of Botany, Agricultural Experiment Station of Kansas State Agricultural 



College 



In an earlier publication ^ of the Kansas Agricultural Experiment 

 Station, data were presented to show that yellow-berry in wheat is 

 heritable and that improvement in the ability of wheat to resist the disease 

 can be accomplished by breeding. The investigations reported therein 

 have been extended, and some studies pertaining to the physiological 

 processes that result in yellow-berry have been made. It is the purpose 

 of this paper to present the results of these later studies.^ 



THE NATURE OF YELLOW-BERRY 



The yellow-berry problem has two aspects, the one practical, the other 

 theoretical. The presence of yellow-berry in wheat causes it to grade 

 lower and sell at a lower price than clear, hard wheat high in gluten. 

 Furthermore, as Bailey says (i, p. i8) : 



If the kernels are soft in texture, or represent what is termed the "yellow-berry" 

 condition, the percentage of flour will be reduced, since it is mechanically impossible 

 to free the bran from the floixry portions so nearly as when the endosperm is hard 

 and vitreous. 



It is apparent that if the yellow-berry condition were eliminated from 

 hard wheats, the practical interests of both the grower and the miller 

 would be subserved. 



The term yellow-berry has been defined by Roberts and Freeman 

 (6, p. i) as — 



the appearance [in hard, flinty wheats] of grains of a light yellow color, opaque, soft, 

 and starchy. These opaque yellow grains, constituting what are called the " yellow 

 berries," may have this character throughout; but sometime from a small fraction to 

 half of a grain will be yellow and starchy, while tlie remainder of the kernel will be 

 hard, flinty, and translucent. The difference in color between the flinty grains and 

 the "yellow berries " is due to differences in the structure and contents of the cells 

 of the endosperm. 



The cause of yellow-berry in wheat has been the subject of some in- 

 vestigation. It appears to have been reported first by Bolley (2, p. 35-36) , 

 who held that the opaque, yellow spotting of the kernels was due not to 

 heredity but to climatic factors, and that — 



this peculiar mottling is due to the action of moistiu"e, air, and sun upon the grain 

 while it is yet in the chaff. If the weather action is long continued, the grains become 

 evenly bleached over the entire siuface. The color and hardness of the grain can be 

 maintained by proper care in harvesting and curing. 



' Reference is Tnade by number (italic) to " Literature cited," p. 169. 



' Credit is due the Department of Chemistry for the chemical analyses reported herein. 



Journal of Agricultural Research, Vol. X\TII, No. 3 



Washington, D. C. Nov. i, 1919 



sr Key No. Kans.-ip 



134793°— 19 4 (155) 



