Genetic improvement of yield responsiveness to nitrogen fertilization and its physiological determinants in barley

摘要: Traditionally, barley in Argentina has been cultivated low-yielding environments. A study was conducted to test whether breeding for improved performance under these conditions would have also the responsiveness nitrogen availability. Four cultivars of two-rowed malting (released 1944, 1960,1982 and 1998) were grown 4 rates fertilizer at sowing (20, 50, 110and 160 kgN ha-1). All increased their yield with increase soil nitrogen. But modern responded more strongly than old ones. For cultivars, grain 12 ± 0.6 kgha-1 each 10 kg ha-1 mean (environmental index). Absolute values genetic gain related availability: 1.59, 2.58, 4.52 4.29 g m-2 year-1 N20, N50, N110 N160 treatments, respectively. Grain associated number m-2, which dependent on spikes grains spike-1. Total biomass maturity explained changes yield. It is concluded that selection stress was, this case, beneficial identify high yields a wide range availabilities.