Abstract: Combined effects on soil microbial activity of nutrient and pest management in hybrid rice double annual cropping system were studied. The results of field experiment showed significant changes in soil parameters with different management practices and at different growth stages. Marked depletions in the soil microbial biomass phospholipid contents were found with the advancement of crop growth stages, while the incorporation of fertilizers and/or pesticides also produced slight changes, the lowest microbial biomass phospholipid content was found with pesticides alone application. A decline in the bacterial abundance of heterotrophic bacteria and proteolytic bacteria was observed with the continuance of crop growth stages, and the lowest abundance of heterotrophic bacteria and proteolytic bacteria was found with pesticides alone application, which coincided with the similar decline of soil microbial biomass. A consistent increase in the electron transport system (ETS)/Dehydrogenase activity was measured during the different crop growth stages of rice. The use of fertilizers (N,P,K) alone or together with pesticides increased electron transport system activity, while a decline was noticed with pesticides alone application as compared with the control. The soil protein content was found nearly stable with fertilizers and/or pesticides application at various growth stages in both crops taken, but notable changes were noticed at different growth stages.

Key words: nutrient management, pesticide management, soil microbial activity, hybrid rice

摘要： 田间实验表明在不同的管理方式和不同生长期所研究的土壤参数均发生显著变化。土壤微生物生物量/磷脂含量随水稻生长期延长而显著减少，同时，单独施用肥料或农药和同时施用肥料和农药均导致土壤微生物生物量/磷脂含量发生一定变化，单独施用农药的土壤中土壤微生物生物量/磷脂含量最低。异养型细菌和蛋白质分解菌数量随水稻生长期延长持续减少，单独施用农药的土壤中异养型细菌和蛋白质分解菌数量最少，异养型细菌和蛋白质分解菌数量的变化趋势与土壤微生物生物量/磷脂含量相似。电子运输系统/脱氢酶活度随水稻生长期延长持续增强。与对照相比，单独施用肥料或同施农药和肥料导致土壤中电子运输系统活度增强，而单独施用农药土壤中电子运输系统活度明显下降。单独施用肥料或农药及同时施用肥料和农药处理中，土壤中蛋白质含量相对稳定，但在不同生长期存在较大变化。关键词

关键词: 养分管理, 农药管理, 土壤微生物活性, 杂交水稻