关键词: 主成分分析, 主成分分析, 综合评价, 土壤养分, 湘西

Abstract:

Using three rice genotypes with different nitrogen use efficiency (NUE) and three rice genotypes with different nitrogen harvest index (NHI), the effects of nitrogen rates (0 kg N?ha-1, 180 kg N?ha-1 and 360 kg N?ha-1) on accumulation and transfer of dry matter and nitrogen in relation to NUE and NHI were investigated in pot experiments. The results showed that the increasing nitrogen rate reduced NUE and NHI, and the genotypic differences of NUE in low nitrogen and NHI in high nitrogen were highest. The increasing nitrogen increased accumulation and transfer amounts of dry matter and nitrogen over the whole growth period and after anthesis in rice. The ratio of dry matter and nitrogen transfer to grain and contribution ratio of transferred dry matter and nitrogen to grain in rice genotypes with different NHI increased with the increasing nitrogen rate, but those in rice genotypes with different NUE reduced. The differences of pre-anthesis dry matter accumulation and post-anthesis dry matter transfer amount in different rice genotypes with NUE were the largest and the differences of post-anthesis dry matter accumulation and post-anthesis dry matter transfer amount in different rice genotypes with NHI were the largest. The difference of post-anthesis nitrogen accumulation in different rice genotypes with NUE was the largest and the differences of post-anthesis nitrogen accumulation and transfer amount in different rice genotypes with NHI were largest. Correlation analysis indicated that the relationships between NUE and total dry matter accumulation, post?-anthesis nitrogen accumulation, ratio of nitrogen transfer to grain and contribution ratio of transferred nitrogen to grain were significant, the relationships between NHI and post-anthesis dry matter transfer amount and contribution ratio of transferred nitrogen to grain were maximum. It is suggested that increasing total dry matter accumulation, decreasing post-anthesis nitrogen accumulation and accelerating post-anthesis nitrogen to grains in rice were the important approaches for increasing NUE, increasing post-anthesis dry matter accumulation and contribution ratio of transferred nitrogen to grain in rice were advantage for increasing NHI.