菜地土壤及小麦、水稻根围土壤中的腐霉及其种群消长

对杭州市郊菜地土壤、小麦根围土壤及水稻根围土壤中的腐霉种类及消长规律进行了较系统的研究，共分离鉴定了１６个腐霉种，土壤中的腐霉种群数量消长呈明显的季节性，以冬春季为高峰，而夏秋季较少；小麦和水稻根围土壤中的腐霉则与作物生育期有关，作物生育前期腐霉种群数量达到高峰，后期减少。

Fluctuation of Pythium Species from Vegetable Field Soil and Rhizosphere Soil of Wheat and Rice

Pythium species and their fluctuation from vegetable root-free field soil and wheat/rice rhizosphere soil in the suburbs Hangzhou were studies in this paper. 16Pytheium species were identified in this studies, and seasonal variations of Pythium spp.were found. Generally,the highest Pythium population levels were in cool and humid season (winter and spring)and lowest in hot and dry summer. The fluctuations of Pythium spp. from wheat/rice rhizosphere soil related to the stages of plant,the population peaks were in early growing stages of plants.