应用^(15)N示踪技术对不同品种大豆的三种氮源吸收利用的研究

STUDY ON THE DIFFERENCES OF NITROGEN NUTRITION OF 3 SOYBEAN CULTIVARS BY USING ^(15)N ISOTOPE DILLUTION METHOD

试验中以３ 个大豆品种为供试作物， 设两个氮水平。试验结果证明施氮水平由 Ｎ１ 增加到 Ｎ２ 时， ３ 个品种大豆全株的全氮积累随之增加， 其中３ 种氮源也分别有所增加。在 Ｎ１ 和 Ｎ２ 两种氮水平下， ３ 个品种大豆全株中对３ 种氮源的积极累量和分配比例也有所不同。

A pot experimcnt has been conducted to study on the differences of nitrogen nutrition from different soybean cultivars. Dongnong-42, Heinong-37 and 90681 have been selected to grow at 2 N rates at this pot experiment. Nitrogen-15 isotope dillution method has been used in estimating nitrogen fixation, the total N accumulations of these 3 soybean cultivars all increase with N rate up from N1 to N2, and that of Heinong-37 and 90681 respectively increase 31 20% and 32 40% , but of Dongnong-42 only 4 30%. At N1 rate, Ndfs(Nitrogen derived from soil) of these 3 soybean cultivars is about 61 605～68 60% total N, and Ndff (Nitrogcn derived from fixaxion) is about 27 7%～34 3. At N2 rate, Ndfs is about 45 40%～46 2% of fotal N, which is almost equivalent to Ndff which is ahout 42 2%～45 80%$$$$