苜蓿、牛尾草混种模式的探讨及其固氮评估  

DISCUSSION ON THE PLANTING PATTERNS OF ALFALFA AND MEADOW FESCUE IN MIXED CULTURE AND EVALUATION FOR THEIR CONTRIBUTION FROM N 2 FIXATION

作　　者：姚允寅[1] 张希忠[1] 陈明[1] 

机构地区：[1]中国农业科学院原子能利用研究所

出　　处：《同位素》1996年第2期70-75,共6页Journal of Isotopes

基　　金：国际原子能机构资助

摘　　要：田间试验采用裂区设计，在不同种植模式下采用１５Ｎ示踪研究了苜蓿与牛尾草混播及单播草地的产草量、产氮量和固氮量的变化。结果表明混作条播优于混作撒播和间作条播，前者更有利于发挥豆禾牧草混作草地的优势，三种处理年均牧草干重分别为１５３５．９、１２８０．８和１２４９．３ｇ／ｍ２；相应全氮产量为５０．８３、３６．６５和３６．８６ｇ（Ｎ）／ｍ２，年均固氮量分别为４２．３７、２８．２１和２８．４２ｇ（Ｎ）／ｍ２，年均固氮百分率分别为８３．４％、７７．０％和７７．１％。并对１５Ｎ同位素稀释法、１５Ｎ天然丰度法及全氮差值法测定的固氮百分率和固氮量进行了比较。Effects of planting patterns on dry weight, N yield and dinitrogen fixation in alfalfa meadow fescue pasture are studied by using split plot design in the field for two successive years. The results show that the pattern of row seeding in mixture(RM) is superior to the pattern of broadcasting in mixture (BM) and intercropping(TC), and advantageous to develop the superiority of legume grass mixed pasture. The annual average of dry weight for RM, BM and TC is 1 535.9 g/m 2, 1 208.8 g/m 2 and 1 249.3 g/m 2 respectively. The annual average of N yield of them is 50.83 g(N)/m 2, 36.65 g(N)/m 2 and 36.86 g(N)/m 2. The annual average Ndfa is 42.37 g(N)/m 2, 28.21 g(N)/m 2 and 28.42 g(N)/m 2, and %Ndfa is 83.4%, 77.0% and 77.1% for RM, BM and TC respectively. The comparison of 15 N isotope dilution method, natural 15 N abundance method and total N difference method to measure %Ndfa of herbage for all the treatments are made.

关 键 词：苜蓿 牛尾草 混种 种植模式 固氮 

分 类 号：S54[农业科学—作物学]