Selection for high and low productivity in perennial rye-grass (Lolium perenne L.)

摘要

Summary In Lolium perenne the progress of selection for high and low productivity was slow in the second generation, estimates of heritability being generally of the same order (5–30%) as calculated from the preceding generation of diallel crosses of four plants, selected at random from old pastures. Progress was also influenced by inbreeding depression and some heterosis at different seasons. The effects of selection changed with season, the interaction being most marked in winter. Selection for tiller number was less efficient than the correlated response in tiller number to selection for herbage production. Selection for herbage producti'On yielded correlated responses in date of ear emergence, seed-weight, and total seed production.