异菌脲与戊唑醇、吡唑醚菌酯复配对苹果斑点落叶病菌的联合毒力

Synergistic interaction of the mixtures of iprodione with pyraclostrobin or tebuconazole on Alternaria alternata f.sp.mali

为了筛选异菌脲与戊唑醇、吡唑醚菌酯对苹果斑点落叶病菌(Alternaria mali)毒力增效的最佳配方,采用菌丝生长速率法测定异菌脲与戊唑醇、异菌脲与吡唑醚菌酯不同比例混剂对苹果斑点落叶病菌的毒力,并通过田间试验验证。室内毒力测定结果表明:异菌脲与戊唑醇质量比4∶1对抑制菌丝生长为增效作用,增效系数为1.57,其他配比均表现为不同程度的相加作用;异菌脲与吡唑醚菌酯的混剂对苹果斑点落叶病菌均表现为相加作用。田间防效试验结果表明,异菌脲与戊唑醇质量比4∶1的复配剂对苹果斑点落叶病防效为70.77%~78.90%,与单剂相比防治效果更好,并且用药量更低。

To select the best formulation of the virulence of iprodione,tebuconazole and pyraclostrobin against Alternaria mali,the virulence of different ratios of iprodione and tebuconazole,iprodione and pyraclostrobin against Alternaria mali was assayed in laboratory through the method of colony growth diameter test.The results showed that iprodione and tebuconazole with mass ratio of 4∶1 were synergistic in inhibiting mycelial growth,with a synergistic ratio of 1.57,while other ratios showed different degrees of additive effect;the mixture of iprodione and pyraclostrobin showed additive effect on Alternaria mali.The test results in field showed that the efficacy of the 4∶1 mass ratio of iprodione and tebuconazole against apple alternaria blotch was 70.77%~78.90%,which was better than that of the single agent,and the dosage was lower.