DRY MATTER AND NITROGEN ACCUMULATION AND REDISTRIBUTION AND THEIR RELATIONSHIP TO GRAIN YIELD AND GRAIN PROTEIN IN OATS

Abstract

Dry matter and nitrogen (nitrate and reduced) accumulation and redistribution in four different spring oat (Avena sativa L.) genotypes grown at commercial field density were studied on a plant part and whole plant basis over the growing season for 2 yr. The four cultivars displayed significant differences in plant part and total plant dry matter, harvest index, nitrogen content, nitrogen concentration, nitrogen harvest index, and nitrogen translocated values at most sample dates in both years. Grain yield per plant was correlated with dry matter accumulation (r = 0.80*). Harvest index was highly correlated with grain yield per plant (r = 0.88**). Grain nitrogen content was highly correlated with plant nitrogen content (r = 0.94**). Nitrogen harvest index and harvest index were highly correlated (r = 0.86**), indicating that they may be related processes. Since plant dry matter and plant nitrogen content were not significantly correlated, it should be possible to select simultaneously for these traits to effect grain yield and grain nitrogen content increases on a per plant basis. Further research will have to be done to determine how these changes will relate to grain nitrogen concentrations and grain yield per unit area.Key words: Avena sativa L., oat, dry matter, nitrogen, yield, protein