棉田土壤黄萎病菌微菌核的研究

Microsclerotium of Verticillium pathogens at cotton field soil

用改良选择性培养基对棉田土壤黄萎病菌检验结果表明,黄萎病菌在土壤中一年的消长变化以5—7月份微菌核居多,6月份达最大值。89.13%的微菌核分布在0—40cm 土层内,仅有10.8%的微菌核分布在40cm 以下的土层中.地膜覆盖棉田黄萎病的发生比露地棉田早,发病也较重。小麦、玉米与棉花轮作2年以上的棉田微菌核减少.

Using improved selective media for the identification of Verticillium wilt patho-gens in the cotton soil,it revealed the dynamics of that pathogens in the soil that theamount of micro-sclerotium was dominant in 5—7th months in a year and at June itreached the peak.89.13% of the micro-sclerotium were distributed at a depth of 0—40cm of the soil while only 10.8% of them were below the 40cm level.The incidenceof the disease was earlier at the mulched cotton field than the open field with ahigher rate of infection.Rotation with wheat and corn for more than 2 years wouldchcrease the amount of micro-sclerotium at cotton field.