GRAIN-YIELD, GRAIN NITROGEN CONCENTRATION AND SOME ASSOCIATED PHYSIOLOGICAL ATTRIBUTES OF A SEMIDWARF AND TALL ARGENTINEAN WHEAT CULTIVARS

We studied the effects of the semidwarfing genes on accumulation and distribution of dry matter and nitrogen through a tall and semidwarf Argentinian cultivars. In two field experiments the semidwarf cultivar showed a greater grain yield than the tall one. This was attributed to its higher harvest index associated to a higher number of grains per m2. Similarly, Buck Pucara showed both a greater grain nitrogen yield and a higher nitrogen harvest index. There was no difference in grain nitrogen concentration. Most of the main differences between cultivars were defined before the anthesis stage.