Response to two-way selection for harvest index in two wheat (Triticum aestivum L.) crosses

Abstract

A two-way selection experiment was conducted during 1974 and 1975 with two wheat (Triticum aestivum L.) crosses with a view to measuring the direct response of harvest index and its correlated response of grain yield. In the F2 generation, 10% selection intensity was applied for high as well as low harvest index and the selected populations were grown in the F3 generation. The progenies selected for low harvest index in the F2 generation gave low harvest index in F3 plants also, while those selected for high harvest index in the F2 generation segregated into high and medium harvest index in F3 plants. Simple and partial correlations of plant weight and grain yield with harvest index suggested a moderate to high positive association of grain yield with harvest index in the F3 generation. Estimates of heritability and gain from selection were high. The crosses under study provided evidence on the possible use of harvest index as a selection criterion for yield improvement in early segregating generations.