Relation between green area duration and grain yield in some varieties of spring wheat.

Spring wheat cv. Opal, Orca and Gaby, sown in 1967-8 on various dates at different seed rates or with different levels of N and chlormequat, were assessed for green area of leaves, internodes and ears. Green-area duration (D) for flag leaf and for peduncle were closely correlated with grain yield, the combined value for the 2 parameters accounting for 81 and 61% of the variance in grain yield in the 2 years, respectively. Including all the values of D in a multiple correlation increased the predictive value to 83 and 74%. D for ears was closely correlated with grain yield in 1968 only. The grain: leaf ratio was higher for Gaby than for the other 2 cv. (Abstract retrieved from CAB Abstracts by CABI’s permission)