Effects of different nitrogen and water treatments on phytic acidcontents and protein components in rice grain

Two rice genotypes (Xiushui 110 and Chunjiang 15) were used to analyze the influence of nitrogen treatments, water management methods and their interaction on grain phytic acid content and protein components by a field experiments of two water treatments, including traditional irrigated cultivation (C1) and dried stress cultivation (C2) with 3 level nitrogen fertilizers (N1, 0 kg/ha; N2, 100 kg/ha; N3, 200 kg/ha) for each water treatment. The results showed that C2 treatment (dried stress cultivation) had relatively higher phytic acid content in rice grain, while the effect of nitrogen treatments on grain phytic acid were water managementdependent, with slight high phytic acid content for 100 kg/ha nitrogen application (N2) and no nitrogen application (N1) relative to high nitrogen treatment(N3) under the condition of traditional irrigated cultivation (C1), but the opposite was true for the effect of N treatment to grain phytic acid when C2 treatment was exposed. The varying contents of grain phytic acid for different water and level nitrogen fertilizers were poorly correlated with grain total protein, 4 protein components and rice yielding traits (available panicle per areas, grain number per panicle, 1000grain weight and seed setting rate), although the decreasing yield levels and low grain quality generally occurred at the extremely high application of N fertilizer; The varying extent of phytic acid, total protein contents and 4 protein components in different grains within a panicle was also related to water management and N fertilizer application, with relative high phytic acid for the bottom location grains compared to those located at upper and middle location within a panicle, implying that appropriate water management and N fertilizer application were generally benefit for the reduce of grain phytic acid content except for achieving a high yield level in rice production.