弱光对杂交稻氮素积累、分配与子粒蛋白质含量的影响

Effect of low-light stress on nitrogen accumulation, distribution and grains protein content of Indica hybrid

以 3个不同基因型的中籼杂交稻组合为材料 ,利用遮荫制造 3种光强研究了灌浆期间弱光对水稻氮素积累、分配及子粒蛋白质含量的影响。结果表明 ,弱光下植株各器官的氮含量均上升 ,遮荫处理后 2 8d叶片氮含量比对照增加 7.2 0 %～ 2 5 .2 3% ,遮荫期间茎鞘平均氮含量比对照高 36 .5 7%～ 5 6 .16 % ,穗平均氮含量比对照高 11.35 %～ 2 9.89%。遮荫后子粒蛋白质含量极显著上升 ,4 9%遮荫、6 9%遮荫处理分别比对照高 14 .6 2 %、37.5 9%。弱光下植株对氮的吸收强度及累积量减少 ,氮素分配比例改变 ,分配到叶片、茎鞘的氮素增加 ,分配到穗部的减少 ,且叶片和茎鞘的氮素输出量以及穗的氮素输入量呈低于对照的趋势。子粒蛋白质产量随光强下降极显著降低。

A three-replicate, split-plot design was used with 3 species as main plot treatments and 3 light densities as the subplot treatments. Light treatments were under control, wrapped with one layers of 49%-shade and two layers of 69%-shade. Shading treatments began after 10% panicles heading. The plants dry weight, nitrogen content, yield and protein contents of grains were measured. The results of the experiment showed that the nitrogen contents were higher under low-light stress than control. The nitrogen content of leaves at 28d after shade increased 7.20%-25.23% relative to control, and the average nitrogen contents under low-light higher 36.57%-56.16% of stems and sheaths and 11.35%-29.89% of panicles than control. The protein content of grains increased significantly followed light densities decreased, and it was 14.62% higher under 49%-shade and 37.59% higher under 69%-shade. But the N accumulation amount per day decreased under low light. At the same time, the distribution rate of nitrogen to leaves, stems and sheaths increased, and to panicles decreased under low light. The export rate of the nitrogen from leaves, stems and sheaths and the import of the nitrogen to panicles under low light were lower than control. The grains protein yield under low light were significantly lower than control.