三种土壤中大豆根瘤菌共生固氮量估测

EVALUATING SYMBIOTIOTIC NITROGEN FIXATION OF INDIGENOUS RHIZOBIUM JAPONICUM IN THREE TYPES OF SOIL

摘要:

在三种不同土壤上大豆根瘤菌共生固氮量黑土为122.5～129.5公斤/公顷/年。白浆土为95.04～158.6公斤/公顷/年,淡黑钙土为68.5～163.4公斤/公顷/年。三种土壤上无明显差异。种一年大豆,大豆生长期从生物固氮获得氮占大豆全氮百分数来看,白浆土47.9～67.0%,黑土60.5～74.1%,淡黑钙土为50.1～74.5%。
从本试验看大豆的氮素来源主要从根瘤菌共生固氮获得,占50.1～74.1%。其次从土壤获得21.2～47.3%。肥料氮利用较少,仅2.54～4.75%,固定的氮对大豆生殖生长有良好作用。

Abstract:

In pot and field experiments, the amount of N₂ fixed by rhizobium japonicum was estimated bycacalculating the difference between the total nitrogen contained in nodulating and non-nodulating islines of soybean cv.Harosoy and by isotope dilution AN-value method and differerence method in three types of soil (light chernozem, Baijing soil and black soil) in Jilin province.The result; (1) In general, the amount of N₂ fixed was 68.5-163.4 kgN/ha.year in light chernogem, 95.04-158.6 kgN/ha.year in Baijiang soil and 122.5-129.5 kgN/ha.year in black soil.There were no obvious difference in the amount of N₂ fixed among the three types of soil. (2) The percentage of N₂ in the plant of soybean derived from N₂ fixation was 47.9-67.0% in Baijiang soil, 60.5-74.1% in Black soil and 50.1-74.5% in light chernozer. (3) The nitrogen of soybean plant was derived from N₂ by nitrogen fixation 50-74.1% mainly, and from soil 21.2-47.2% and a little from fertilizer 2.54-4.25% in this experiment. The nitrogen derived from N₂ was more available to the reproductive growth of soybean.