赛克津(Sencor)对大豆生育、共生固氮及土壤微生物的影响

本研究结果表明,在土壤有机质含量2.25％～2.35％,土壤水分条件较好的情况下,不同浓度的赛克津除草剂进行土壤处理对大豆种子发芽和幼苗出土均无影响。施量高于0.25 kg/ha的各浓度处理对大豆幼苗均产生药害,药害程度随苗期的延长,用药浓度的增加而加重。开花期的株高和株重,各处理均低于对照。赛克津低浓度0.25 kg处理对大豆根瘤的共生固氮无不良影响;而0.5 kg以上浓度处理,对大豆根瘤的形成和株固氮总活性有较明显的抑制作用。成熟大豆植株的株高(除0.25 kg外),分枝数、荚数、株重及株粒重均低于对照,随用药浓度的增加而降低。赛克津除草剂对土壤中细菌,放线菌和霉菌在数量上有一定刺激作用。

THE EFFECT OF SENCOR ON GROWTH AND DEVELOPMENT OF SOYBEAN SYMBIOTIC NITROGEN FIXATION AND SOIL MICROORGANISMS

This study showed that when the soil organic matter content was 2.25%～2.35% and the soil water condition was favorable, soil treatment with the herbicide, Sencor, of different concentrations had no effect on the germination and emergence of soybean seeds. Treatments with concentration higher than 0.25kg/ha were harmful to soybean seedlings and the harmful effect was enhanced with the increase of seedling age and the concentration of Sencor. soybean plant height and weight during the flowering period in all treatments were lower than check. A low concentration of 0.25kg/ha of Sencor was harmless to symbiotic nitrogen fixation of the soybean root nodules, but concentrations higher than 0.5kg/ha significantly suppressed the formation of soybean nodules and the total nitrogen fixing activity of the plant. Plant height(except 0.25 kg/ha), numbers of branches, and pods, plant weight and seed weight per plant were all lower than check in all concentrations and decreased with the increase of concentration. The herbicide Sencor had some stimulative effect on the numbers of soil bacteria, actinomycetes and mold fungi.