氮肥运筹对棉花干物质累积及产量的影响

Effects of Nitrogen Management on Dry Matter Accumulation and Yield of Cotton

为了寻找最佳氮肥施用时期和比例,提高氮肥吸收利用效率,在氮肥施用总量固定为225 kg/hm2的情况下,调整施肥时期和比例,研究氮肥运筹对棉花(Gossypium hirsutum L.)干物质累积和产量的影响。结果表明,①底肥主要影响营养器官干物重,而对生殖器官干物重没有明显影响,适量的底肥有利于在蕾期和初花期获得较高的生物量;②固定底肥用量为30%时,剩余氮肥全部用于初花期与分两次施用于初花期和盛花期最终获得的生物量和产量相当;③合理的氮肥施用策略有利于提高快速累积期的平均速率、最大速率和快速累积期积累的干物质,最终有利于获得较高的棉花产量。

In order to determine the optimal applying time and proportion of nitrogen fertilizer, and to improve the utilization efficiency of nitrogen absorption, the applying time and proportion of nitrogen fertilizer was adjusted with the fixed nitrogen fertilizer rate of 225 kg / hm2. Effects of nitrogen management on dry matter accumulation and yield were studied of cotton（Gossypium hirsutum L.）. The results showed that the applying amount of base fertilizer mainly affected dry matter weight of the nutritional organs while no significant effects on the dry matter weight of reproductive organs. The appropriate amount of fertilizers at early stage of flowering was beneficial to obtain high biomass. With the fixed fertilizer amount of 30%,the biomass and yield were same when the residual nitrogen fertilizers were all used at stage of flourishing flowering or used once at stage of flourishing flowering and another once at initial stage of flowering. Reasonable nitrogen fertilization strategy could improve the average speed,maximum speed, dry matter accumulated in the fast accumulation period,finally leading to high yield of cotton.