苯噻草胺对水田土壤呼吸强度和酶活性的影响

EFFECTS OF MEFENACET ON MICROBIAL RESPIRATION AND ENZYME ACTIVITIES IN PADDY SOIL

研究了除草剂苯噻草胺对水稻田土壤呼吸强度和酶活性的影响。表明苯噻草胺使用后初期刺激土壤呼吸作用但随后产生轻微抑制 ,能激活脱氢酶的活性 ,但抑制过氧化氢酶活性随后产生一定的刺激作用。苯噻草胺强烈抑制脲酶活性 ,轻微抑制蛋白酶活性 ,但对磷酸酶具有刺激作用 ,而且随苯噻草胺施用浓度的增加而刺激作用增强。

This paper deals with the influences of herbic ide mefenacet on soil respiration and the activities of dehydrogenase, catalase , urease, proteinase and phosphorylase in paddy soil. The results showed that after application of mefenacet with concentration of 0.067,0.100,0.133,0.200 and 0.267 μg g -1 dried soil, soil respiration was stimulated at the beg i nning but reduced slightly afterwards, and the activity of dehydrogenase was en hanced in paddy soil. The soil catalase was less active than dehydrogenase, eve n inhibited within the first two weeks. The soil urease was strongly depressed a nd the activity of proteinase took on the slight inhibition within the whole per iod of experiment. The activity of phosphorylase, however, was raised with the increase of mefenacet concentrations within the first 18 days. Mefenacet had lo wer effects on soil respiration and enzyme activities than butachlor, an old ge neration of herbicide.