施氮水平对棉花农艺性状、倒四叶光合特性及产量的影响

Influence of Nitrogenous Fertilizer Level on Agronomic Characters,Fourth Leaf from Top Photosynthetic Characteristics and Yield of Cotton

研究了5种不同氮素水平(kg/hm2):337.5(N1),450.0(N2),562.5(N3),675.0(N4),787.5(N5)对棉花倒四叶及产量的影响。结果表明:N3,N4水平的氮素处理倒四叶叶宽、光合速率要大于其他处理,叶绿素含量也具有类似趋势,说明氮肥影响叶绿素含量的变化,而倒四叶叶柄硝态氮含量在初花期与施氮量具有一定的相关性且随氮肥用量的增加呈上升趋势。各处理棉花产量N3>N4>N5>N2>N1,最高皮棉产量3 156.0 kg/hm2,最低1 942.5 kg/hm2。表明只有合适的氮肥量才能促进源库关系的协调,使叶片合成的光合产物向棉铃的输送效率提高,促进棉铃数量增多、库容扩大、提高产量。

The present objective of this article was to investigate the influence of 5 kinds of different nitrogenous fertilizer level 337.5 kg/hm^2 （N,）, 450.0 kg/hm^2 （N2）, 562.5 kg/hm^2 （N3） ,675.0 kg/hm^2 （N3）, 787.5 kg/hm^2 （N5） on fouth leaf from top photosynthetic characteristics and yield of cotton. The results indicated that nitrogen processing four blade widths, photosynthetic speed rate of N3, N4 were greater than that of other processing,but actually the chlorophyll content also had the similar tendency,which showed that nitrogenous fertilizer had influence on the change of chlorophyll content, but four petiole nitric nitrogen content had a certain relativity with nitrogenous fertilizer amount in the first flowering stage. It was increased with the increase of amount of nitrogenous fertilizer. Based on its influence on yield of cotton, the： order of yield of cotton with different processing were as following： N3〉 N4 〉 N5 〉 N2 〉 N1. The highest cotton-lint was 3 155.0 kg/hm^2 ,but its lowest yield was 1 942.5 kg/hm^2 ,which indicated that only when amount of rational nitrogenous fertilizer was applied,the source warehouse relation coordination would be promoted, the quantity of cotton boll would be increased and the storage capacity of cotton would be expanded.