不同氮肥施用量对大豆生长状况的影响

Effect of Different Nitrogen Fertilizer Amount on the Growth of Soybean

为了摸清氮肥施用量对大豆生长状况的影响,设置不同梯度氮肥试验。结果表明:施用氮肥能够显著增加大豆株高、叶绿素含量,促进植株干物质的积累,不同施氮水平下,株高和叶绿素含量以及植株生物量在N3P2K(高氮)处理中达到最大值,但对大豆根瘤的形成和生长则表现出抑制作用,表现为减少根瘤数量和根瘤干重,降低固氮酶活性。与低氮处理相比,其它处理的根瘤固氮酶活性较弱。增加施氮量能够改善大豆产量性状,增加大豆单株荚数和粒数,但与N1P2K(低氮)处理相比,N2P2K(中氮)、N3P2K(高氮)处理的产量稍有下降,分别减少了6.8%、1.1%。

In order to find out the effect of nitrogen fertilizer amount on the growth of soybean,different gradient nitrogen tests was conducted. The results showed that the application of nitrogen fertilizer could significantly increase the plant height and chlorophyll content of soybean, and promote the dry matter accumulation. Plant height,chlorophyll content and biomass of plants were the maximum under N3P2K treatment which inhibited the formation and growth of soybean rhizobia,reduced the number of nodules and nodule dry weight,decreased nitrogenase activity. Compared with low nitrogen amount treatment,other treatments got the weak of nitrogenase activity of nodules. The yield of soybean improved, pod number per plant and grain number could be increased with the increasing of the nitrogen fertilizer amount . However, compared with N1P2K, the yield of N2P2K and N3P2K decreased slightly by 6.8 % and 1.1%, respectively.