水稻耐氨固氮菌施用效应研究

早、晚两季的田间试验结果表明，在电脑推荐施N水平上,耐氨固氮菌的增产效果不显著；在低N情况下(每公顷减纯N37.5kg)，耐氨固氮菌的增产效果达显著水平，早、晚稻分别增产8.41％和7.21％。15N示踪盆栽试验结果表明，耐氨固氮菌对根系生长有明显的促进作用，在秧苗期明显增加秧苗对肥料15N的吸收．禾苗分蘖盛期则增强了禾苗根系的吸氮能力。

Effects of Ammonia Resistant Strains of N2-fixing Bacteria on Paddy Rice

Field trials were conducted on the early rice and the late rice. The results showed that the yield increased by Ammonia Resistant Strains of N2-fixing Bacteria (ARSNFB) was insignificant when nitrogen was supplied enough at the recommended amount. But the increased yields were significant when nitrogen supply was lower (when N was decreased by 37.5 kg/hm2 ), which were 8.41% in early rice and 7.21% in late rice. In pot trials with 15N tracer, root growth was evidently promoted by ARSNFB, the 15N contents of paddy shoots were increased, and nitrogen absorption capacity was enhanced at peak tillering after transplanting.