硒对水稻碳氮代谢及产量的影响

通过盆栽模拟试验研究了硒对水稻生长、碳氮代谢以及产量的影响。结果表明,施硒显著提高了水稻叶片、根及大米中硒的含量,硒对水稻株高影响不大,但显著提高了水稻的秸秆鲜重以及籽粒产量;施硒能提高水稻叶片的叶绿素含量,对光合速率具有提升作用,增强了水稻对光合碳的同化能力,从而提升了植株根及叶片的可溶性糖含量;施硒显著提高了水稻叶片及根中谷氨酸脱氢酶、谷氨酰胺合成酶、谷氨酸合成酶以及硝酸还原酶的活性,增强了水稻对氮素的同化代谢能力;硒对碳氮代谢产物可溶性蛋白影响不大,但是在显著提高水稻叶片氮含量的基础上降低了中间代谢产物游离氨基酸的含量,说明硒促进了碳氮代谢中间产物游离氨基酸向大分子有机含氮化合物的转化。试验结果说明,硒对产量的提升作用可能是通过影响碳氮代谢过程来实现的。

Effects of selenium on carbon nitrogen metabolism and yield of rice

A pot experiment was conducted to determine the effects of application of Se on growth, carbon-nitrogen metabolism and yield of rice. The results showed that application of Se increased leaf, root and rice grain Se contents, straw fresh weight and grain yield, but application of Se had no significant effect on plant height of rice. Application of Se increased SPAD, pho-tosynthetic rate and capacity of photosynthetic carbon assimilation, and then enhanced root and shoot soluble sugar contents. Application of Se increased activities of glutamate dehydrogenase, glutamine synthetase, glutamate synthase and nitrate reduc-tase, and then enhanced the assimilation of nitrogen in rice. Application of Se had no significant effect on soluble protein con-tent, but application of Se increased leaf nitrogen content and decreased intermediate metabolite free amino acid content, which showed that application of Se promoted free amino acid to convert into macromolecular organic nitrogen compounds. This study suggested that the application of Se increase grain yield of rice might be due to the reason of increasing the carbon-nitrogen me-tabolism ability.