氮肥运筹对水稻养分吸收特性及稻米品质的影响

以水稻品种扬两优6号为材料,研究了田间条件氮肥运筹对水稻养分吸收及产量和品质的影响。结果表明,高氮处理(N240)成熟期氮素积累总量、磷素积累总量和钾素积累总量分别比中氮(N150)和低氮处理(N0)增加了21.5%、18.5%1、8.3%和134.6%、127.0%和82.7%;产量增加了10.4%和39.6%。在相同氮素水平下,采用B种施肥比例(基肥∶分蘖肥∶穗粒肥=30%∶20%∶50%),水稻成熟期氮素积累总量比A处理(基肥∶分蘖肥∶穗粒肥=40%∶30%∶30%)增加了15.4%,产量提高了7.3%。在高氮处理(N240)条件下,采用B施肥比例,蛋白质含量显著提高,直链淀粉显著降低,但提高了稻米的垩百度而使稻米外观品质变劣。

Effects of nitrogen management practices on nutrition uptake and grain qualities of rice

Effects of nitrogen management practices on nutrition uptake and grain qualities of rice were examined using a rice cultivar, Yanglianyou 6, in a field study. The nitrogen fertilizer was applied in three splits, namely, 40% as basal, 30% at 10 days after transplanting (DAT) and 30% at 36 DAT (40-30-30), and 30% as basal, 20% at 10 DAT and 50% at 36 DAT (30-20-50), and the N application rates were set to N 0, 150 and 240 kg/ha, expressed as N₀, N₁₅₀ and N₂₄₀, respectively. Compared to the N₁₅₀ and N₀ treatments, total nitrogen accumulation (TNA), total phosphorus accumulation (TPA) and total potassium accumulation (TKA) of the N₂₄₀ treatment at maturity stage are increased by 21.5%, 18.5%, 18.3% and 134.6%, 127.0%, 82.7%, and rice yields are increased by 10.4% and 39.6%, respectively. Under the same nitrogen application rate, TNA and yield of the 30-20-50 split are 15.4% and 7.3% higher than those of the 40-30-30 split at the maturity stage. The grain protein of rice is improved significantly; while grain amylose content is decreased, and the quality of appearance is worsen due to the improvement of chalkyness of grain under the N₂₄₀ treatment with the 30-20-50 split.