表油菜素内酯对冬小麦产量及氮素吸收、积累和分配的影响

为明确表油菜素内酯对高产小麦氮素吸收积累和产量的调控作用,以小麦品种石麦18为材料,设置起身期、起身期+孕穗期、孕穗期3个喷施时期为主区,0~0.15mg·L-1 4个喷施浓度为副区的裂区试验,测定小麦各器官含氮量、产量及其构成因素。结果表明,起身期或孕穗期1次喷施或起身期+孕穗期2次喷施0.05或0.1mg·L-1表油菜素内酯时,小麦穗粒数、千粒重和产量均提高。喷施以后植株含氮量和氮积累量增加,生育后期氮在茎和穗中的分配比例提高,氮的净吸收量和花后向籽粒的净转运量增加。其中,起身期喷施或起身期+孕穗期2次喷施0.1 mg·L-1表油菜素内酯的上述作用最显著,孕穗期喷施0.05mg·L-1的上述作用最显著。在所有处理中,起身期+孕穗期2次喷施0.1mg·L-1的效果最明显,其次为起身期喷施0.1mg·L-1。起身期喷施的作用高于孕穗期喷施。因此,冬小麦应用表油菜素内酯,以起身期或起身期+孕穗期2次喷施0.1mg·L-1为宜。

Effect of Epibrassinolide on Grain Yield, and Absorption, Accumulation and Distribution of Nitrogen in Winter Wheat

In order to clarify the regulating effects of epibrassinolide on absorption and accumulation of nitrogen, and yield of highly-yielding winter wheat,a field experiment designed as spilt plots, with three foliar spraying stage combinations of erecting stage, erecting & booting stage, booting stage, as main plots, and four spraying concentrations of 0, 0.05, 0.1 and 0.15 mg·L^-1, as split plots, was conducted with a wheat variety Shimai 18 as material.Nitrogen content in wheat plants,yield and its components were determined. The results showed that, the grain number per spike, grain weight and grain yield of wheat increased in the treatments with 0.05 or 0.1 mg·L^-1 epibrassinolide sprayed at erecting stage or booting stage or both stages. And for these treatments, the content and accumulation amounts of nitrogen in wheat plants, the distribution percentage of nitrogen in stems and spikes during late growing period, the total net absorption and net translocation of nitrogen to grains of wheat all increased. The effects mentioned above was the most significant for the treatment 0.1 mg·L^-1 epibrassinolide among the four concentrations sprayed at erecting stage or double sprayed at erecting and booting stages, but was the most significant for the treatment 0.05 mg·L^-1 among the four concentrations sprayed at booting stage. In all treatments, the effects of epibrassinolide was the most significant for the treatment doubled sprayed 0.1 mg·L^-1 at both stages, then those for the treatment sprayed 0.1 mg·L^-1 at erecting stage. The effects of epibrassinolide sprayed at erecting stage were more prominent than those sprayed at booting stage. According to the results, it is suitable to spray 0.1 mg·L^-1 at erecting stage or at both erecting and booting stages for epibrassinolide application in winter wheat.