大豆生育期间土壤无机态氮与植株硝态氮变化规律的研究

Changes Rule of Content of NO_3^--N and Inorganic-N in the Soil and Plant Analysis during the Growing Seasons of Soybean

试验以2个大豆品种,3种施氮肥水平(N0:0 kg hm-2、N75:75 kg hm-2、N150:150 kg hm-2),对大豆生育期间土壤无机态氮(铵态氮、硝态氮)与植株硝态氮含量及变化规律加以研究,结果表明,土壤中无机态氮与大豆植株中硝态氮含量均呈下降趋势,三种施氮肥水平相比,除土壤铵态氮含量表现为N150>N75>N0,土壤硝态氮与植株硝态氮含量在各氮肥水平处理间未表现出明显的差异,并且大豆茎、叶柄中硝态氮含量与土壤中硝态氮含量呈极显著正相关(r=0.9316**;r=0.9355**),土壤铵态氮与土壤硝态氮含量呈极显著正相关(r=0.8746**,)可以用茎、叶柄中硝态氮含量来表征土壤无机态氮营养状况。

This study was conducted with two soybean cultivars and nitrogen treatments（N0：0 kg hm^-2,N75：75 kg hm^-2,N150：150 kg hm^-2）t,o study the content of NO3^--N in the soil and plant during the growth period.The results showed that the contents of NO3^--N in the soil and plant were downtrend,and the contents of NH4^＋-N in the soil were N150N75N0.The contents of NO3^--N in the soil and plant were no obvious differences among different nitrogen treatments,and there were highly significant correlations between the contents of NO3^--N in stem and petioles and in soil（r=0.9316^＊＊ and r=0.9355^＊＊ respectively）,and the correlation between the contents of NH4^＋-N and NO3^--N in soil reached the positive correlative level（r=0.874^6＊＊.） In conclusion,the contents of NO3^--N in stem and petioles could be used to characterize the nitrogen nutritional status.