草铵膦对麦田土壤微生物数量及酶活性的影响

为给草铵膦的科学使用提供理论依据,设置5个不同草铵膦施用量(0、2、4、6、8L·hm^-2),研究了草铵膦对麦田土壤微生物(细菌、放线菌、真菌)数量及其土壤酶(过氧化氢酶、磷酸酶、脲酶、脱氢酶)活性的影响。结果表明,随着草铵膦施用量的增加,土壤微生物数量随着小麦生育期的推进呈现先增加后减少趋势;在草铵膦施用量为6L·hm^-2时,微生物数量均高于其他处理;细菌和放线菌数量较对照增加,其增加幅度随着小麦生育期的推进逐渐增大,成熟期达到显著水平;喷施草铵膦对真菌数量影响不显著。在低浓度(2、4和6L·hm^-2)草铵膦处理下,被测土壤酶活性均随着草铵膦施用量的增加而增大;在高浓度(8L·hm^-2)草铵膦处理下,酶活性均受到抑制,其中过氧化氢酶与其他处理差异显著。在本试验的条件下,推荐麦田草铵膦的施用量为4～6L·hm^-2。

Effect of Glufosinate-Ammonium on Soil Microbial Biomass and Enzyme Activity in Wheat Field

In order to provide a theoretical basis for the scientific use of glufosinate-ammonium, five different amounts of glufosinate-ammonium(0, 2, 4, 6 and 8 L·hm^-2) were applied, to study the effect of glufosinate on the soil microbe quantity(bacteria, actinomycetes and fungi) and the activity of soil enzymes(catalase, phosphatase, urease and dehydrogenase) in wheat field. The results showed that as the amount of glufosinate increased, the number of soil microorganisms increased first and then decreased with the growth of wheat. The amount of microbe was higher than that of other treatments when the amount of glufosinate was 6 L·hm^-2. The number of bacteria and actinomycetes increased slightly compared with the control, and the increase rate gradually increased with the progress of wheat growth period, and reached a significant level at maturity. The effect of spraying glufosinate on the number of fungi was not significant. Under low concentration(2, 4 and 6 L·hm^-2) glufosinate treatments, the measured soil enzyme activity increased with the increase of glufosinate application rate. Enzyme activity was inhibited under high concentration(8 L·hm^-2) glufosinate treatment. Among them, the activity of catalase is significantly different from that of other treatments. Under the conditions of this test, the application amount of the herbicide glufosinate in wheat field is recommended to be 4 to 6 L·hm^-2.