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过去十年,由于应用了同位素~(15)N稀释技术,人们对非豆科植物的固氮研究取得了进展,这些植物包括甘蔗,牧草,禾谷类作物和放线菌根植物。这些研究结果是在接种和不接种固氮生物的土壤上获得的。本文旨在确定非豆科植物固氮作用的相对和绝对量以及作为农业氮源的作用。同时也指出了现行有效的总体数据和定量测定非豆科植物固氮量实验方法两方面存在的缺点。田间资料表明,非豆科植物联合固氮对热带主要植物N素营养有一定农业意义,其固氮量可能大于30—40kg·N·公顷~(-1),这些植物包括生长在未接种固氮生物、缺氮土壤上的甘蔗和牧草(羊草,臂形草属,和丛生千金子)。测定表明,植物品种间及品种之内在固氮的相对量上有显著的差异。有限的盆栽试验数据表明,在自然条件下、水稻就可营联合固氮获得收益,并且接种后呈现固氮效应。小麦有接种效应、但有些效应似乎并不是联合固氮作用所致。应用~(15)N稀释技术,肯定了放线菌根植物可固定大量的气态氮。
In the last decade, advances in nitrogen fixation of non-legumes have been made due to the use of isotope-15-N dilution techniques, including sugarcane, pasture, cereal crops and actinomycetes. The results of these studies were obtained on soils with and without nitrogen fixation. This article aims to determine the relative and absolute amounts of nitrogen fixation in non-legumes and their role as sources of agricultural nitrogen. At the same time, it also points out the shortcomings of the existing effective data and quantitative experimental methods of non-legume nitrogen fixation. Field data indicate that the combination of non-legumes with nitrogen fixation is of some agricultural significance to the N nutrition of major tropical plants, and the nitrogen fixation amount may be more than 30-40kg · N · ha -1. These plants include those grown on uninoculated nitrogenous organisms, Nitrogen-deficient sugarcane and pasture (Leymus, Aegilus, and Taxus). Determination showed that there was a significant difference in the relative amounts of nitrogen fixation within plant varieties and varieties. Limited pot experiment data show that under natural conditions, rice can combine campylated nitrogen gain, and nitrogen fixation effect after inoculation. Wheat has an inoculation effect, but some of the effects do not seem to be due to a combination of nitrogen fixation. The ~ (15) N dilution technique was applied to confirm that actinomycetes can fix large amounts of gaseous nitrogen.