Investigations on yield in the cereals. I

Abstract

Final yield of grain and straw reflect, or are functions of, the combination of processes conveniently designated “growth.” A successful analysis of “growth” would afford an analysis of “yield” and it is quite patent that “yield” must continue to be imperfectly understood so long as growth remains unanalysed. But although the full solution of the “yield problem” thus rests with plant physiology, it seems within the bounds of possibility that comparative studies upon varieties may bring to light distinctive (varietal) features of “growth” which are correlated with distinctive (varietal) features of “yielding power.” One or more of these may possibly serve as an “index” of yielding power, as the touchstone which is so urgently needed in plant breeding. The reliability of comparative studies of this kind rests fundamentally upon accuracy of “sampling.” For all the experimental attributes of freely tillering cereals, sampling is extremely difficult and the difficulties are most acute for “weight” attributes. Clearly then, a test of accuracy of sampling at all stages of growth is an indispensable preliminary. It was this consideration that determined the lines of the investigation to be recorded here and it is in the light of it that the results will be discussed.