【摘要】 本试验采用乙炔——乙烯还原法(Hardy等人1968)使用SP—2305型气相色谱仪研究了不同施肥方法对大豆结瘤固氮和产量的影响。其主要结果如下:1、大豆施肥必须考虑大豆共生固氮的特点,施肥既能促进根瘤的发育发挥其固氮能力,又能给大豆补充营养。2、在当前生产条件下,种肥每亩施磷5～10斤于种籽下3～5厘米时,据大豆根瘤菌的固氮酶活性测定,大豆生育期的单株固氮量较对照增加61.4％,达到了“以磷增氮”的效果。增产7.9～14.9％。因此,大豆增产重视磷肥的施用是必要的,在缺磷的土壤上效果更显著。3、氮素作追肥,亩追施氮7斤于垅侧开沟深施复土和结荚鼓粒期叶面喷氮肥,亩施尿素1.5～2斤加水60～80斤。氮素主要抑制大豆主根根瘤的发育,对侧根根瘤的发育是促进的,单株根瘤数比对照高16.2～67.6％,单株根瘤重增加4～14.9％,增产10.1～13.1％。结荚鼓粒期叶面喷氮肥,增产4.3～5.9％。更多还原

【Abstract】 The effect of different methods of fertilization on nodulation, nitrogen fixation and seed yield of soybean was studied by ethyne-ethy-lene method using gas chromatograph Model Sp-2305. The results of this study were described as follows: (a) Applicafion of fertilizers not only enhanced the development of nodules and their nitrogen fixing ability,but also supplement nutrients for symbiotic nitrogen fixation of soybean must be of consideration in soybean fertilizer program; (b) Phosphate fertilizer was applied under seeds within a distance of 3-5cm under present cultucral onditions. According to the determination of nitrogenase activity of Rhizobium, the amounts of nitrogen fixation per plant was increased, and the seed yield was increased by 61.4, 7.9-14.9% respectively, and in consequence the porpose of increasing nitrogen was obtained by application of phosphorus; (c) The top-dressing of 3.5kg N per mu was applied deeply at the sides of row and covered with soil immediately, and foliar spray of 0.75-1kg urea as N source with dilution of 30-40 kg water during the periods of pod setting and seed filling. The development of nodules in the main roots was inhibited that in the lateral roots was stimulated by nitrogen. The number of nodules, their weight and seed yield were increased by 16.2-67.6,4-33.9 and 10.1-13.1%, respectively. Foliar spray of nitrogen at pod setting and seed filling cou 1dincrease grain yield by 4.3-5.9%.更多还原