分蘖期冷水胁迫下施氮量对寒地粳稻分蘖消长和产量形成的影响

Effects of nitrogen application on tillering and yield of japonica rice under cold water stress at tillering stage

以3个耐冷性不同的寒地粳稻品种东农428、龙稻7和松粳10为材料,设置7个施氮量水平,在分蘖期进行冷水处理,研究分蘖期冷水胁迫下施氮量对寒地粳稻分蘖消长和产量形成的影响。结果表明,冷水胁迫下寒地粳稻分蘖生长速度下降,最高分蘖数、有效分蘖率、有效穗数、每穗粒数、千粒重、结实率和产量均降低。随着氮肥用量的增加,分蘖生长速度加快,最高分蘖数增加,分蘖盛期推迟,有效分蘖率、千粒重、结实率下降。100 kg/hm2的氮肥用量下寒地粳稻的有效穗数、每穗粒数、产量及产量冷水反应指数最接近对照,最能够减轻低温冷害下寒地粳稻产量的损失。

In order to understand the effects of nitrogen application on tillering and yield in rice under cold water stress at tille-ring stage, Dongnong 428, Longdao 7 and Songjing 10 were used as materials. Seven nitrogen application level were conduc-ted. The results showed that the growth rate of tiller, the maximum tiller number, effective tiller number, spike number, kernel number, 1 000-grain weight, seed setting rote and yield decreased under cold water stress during the tillering stage. With the increase of nitrogen application, the growth rate of tiller accelerated, the maximum tiller number increased, the tille-ring stage delayed, the effective tiller rate 1 000-grain weight and seed setting rate decreased. The spike number, kernel num-ber, yield and the CRI value of yield was close to the control under the 100 kg/hm2 of nitrogen application, which significantly reduced the loss of yield under cold water stress at the tillering stage.