用15N富积标记和稀释法研究旱作水稻/花生间作系统中氮素固定和转移

采用花生叶片15N富积标记法和15N同位素稀释法两种标记方法研究了水稻 花生间作条件下花生的生物固氮以及花生向水稻的氮素转移。盆栽结果表明,两种方法都证明在水稻花生间作的共生期内发生了氮素转移,花生固氮量的2%～3.5%转移到水稻体内。同位素稀释试验还表明,间作对花生固氮有促进作用,能提高其固氮效率(BNF)。本文还对两种同位素标记方法的优缺点进行了讨论。

Comparision of two methods used to study the biological nitrogen fixation and nitrogen transfer from peanut to rice in aerobic soil of intercropping system

Pot experiments was carried to study biological nitrogen fixation and nitrogen transfer from peanut to rice in aerobic soil of intercropping system wi th two different methods: ¹⁵N-foliar feeding and ¹⁵N-isoto pe dilution methods. E vidence of nitrogen transfer was obtained in all of the two methods, which repre sents about 2.0%-3.5% of total N fixed by peanut. Root partition experiments al so suggested that the relative proximity of the root system of the associated tw o components is essential for increasing of N-transfer. The two methods gave id e ntical results. The advantages and disadvantages of the tow methods are also dis cussed in the paper.