氮素营养对小麦干物质积累与转运的影响

Nitrogen Nutrition Affects Dry Matter Accumulation and Transportation in Winter Wheat

在大田条件下,以冬小麦"长旱58"为供试材料,研究不同氮肥用量对小麦干物质转运、积累和分配的影响,共设5个氮水平,即N1(0kg/hm2)、N2(80kg/hm2)、N3(150kg/hm2)、N4(195kg/hm2)、N5(300kg/hm2)。结果表明:在氮肥用量为195kg/hm2的水平下,籽粒获得最高产量,N1处理产量最低。其余茎中干物质对籽粒贡献率最大,而颖壳是灌浆期干物质转运最先发生的部位。N4处理下花后干物质积累最大,而花前同化物转运率最小,N1和N2处理花前同化物对籽粒的贡献率最大,N5处理花后干物质积累小于N4,说明合理的增施氮肥可增加灌浆期光合同化物积累,从而提高产量。

An field experiment was carried out on drought-resistance wheat cultivars changhan-58 （Triticum aestivurn L. ）to investigate how the nitrogen （N） fertilization affects the accumulation, dis- tribution and remobilization of dry matter during the grain-filling period, the treatments involved in five different nitrogen levels： N1 （0 kg/hm2）, N2 （80 kg/hm2）, N3 （150 kg/hm2）, N4 （195 kg/hm2）, N5 （300 kg/hm2）, respectively. The main results showed as following： The highest grain yield was found in N4 treatment, however N1 treatment have lower yield than others. For different source organs, the lower stem contribute most dry matter to grain, but the earliest net remobilization of dry matter happened in glume. The higher dry matter accumulation during post-anthesis and the lower dry matter remobilization efficiency were detected in N4 treatment~ but N1 ,N2 treatments have the highest contribution of pre-anthesis dry matter to grain, it seems that the increase of the N appli- cation allowed the higher dry matter accumulation during post-anthesis, which is a guarantee for the higher yield under semiarid conditions.