【摘要】 在粘壤土中施用 4～ 12μg/ g土三唑酮能提高耐药木霉菌株在西瓜根尖 4～ 1cm处根际土中的种群密度。4 μg三唑酮处理的木霉根际竞争定殖指数、以及在 4～ 8cm和 10～ 14cm根段的根际木霉种群密度均高于不施药对照。土壤接种量为 1× 10 3cfu/ g土时木霉菌在西瓜根际增殖的比例较接种量为 1× 10 6cfu/ g土时大 ,2种接种量下三唑酮处理的根际木霉种群密度分别高于相应的不加药对照。在质地较好、C/ N比值较高的粘壤土中木霉菌在西瓜根际的种群密度较砂壤土和粘土大 ,三唑酮对木霉在西瓜根际的增殖作用也较明显更多还原

【Abstract】 In clay loam soil treated with 4～12 μg triadimefon per gram soil, the population density of Trichoderma harzianum , which is insensitive to the fungicide, was increased in rhizospere at 4～1 cm root tip of watermelon. By the treatment of 4 μg triadimefon, rhizosphere competence index of T. harzianum and its population density at 4 8 cm and 10 14 cm root segments were higher than untreated control. The increased proportion of the population of T.harzianum in rhizosphere soil was higher at the inoculum amount of 1×10 3 cfu/g soil than that of 1×10 6 cfu/g soil, the antagonist population at both inoculum amount with triadimefon treatment were higher than that of untreated control. In clay loam soil with better soil texture and higher C/N ratio, the antagonist population was higher than in sandy loam and clay, and treatment with triadimefon may enable T. harzianum to proliferate in watermelon rhizosphere more obviously.更多还原