吡唑醚菌酯和甲基硫菌灵对2种辣椒炭疽病菌的室内联合毒力测定

Joint-toxicity of Mixtures of Pyraclostrobin with Thiophanate-methyl Against Two Kinds of Colletotrichum spp.

为了提高甲基硫菌灵的防效,延缓抗药性产生,采用菌丝生长速率法和孢子萌发速率法测定了新型杀菌剂吡唑醚菌酯与甲基硫菌灵不同质量比的混合物在室内对2种主要辣椒炭疽病菌的毒力,并对其联合毒力进行了评价。结果表明:吡唑醚菌酯与甲基硫菌灵质量比1︰2、1︰4、1︰16、1︰32的混合物表现出相加作用;其中质量比1︰8的混合物对红色辣椒炭疽病菌的菌丝和孢子增效系数(SR)分别为1.98和1.93,对黑点炭疽病菌的菌丝和孢子增效系数分别为1.95和2.11,表现为增效作用。

In order to improve the control effect and delay the resistance of thiophanate-methyl, the toxicities of pyraclostrobin, thiophanate-methyl and their different ratio mixtures against two kinds of Colletotrichum spp. were determined by the methods of mycelial growth and conidial germination assay, and the joint-toxicities of mixtures were evaluated in this paper. The results showed that the mixtures of 1 ： 2, 1 ： 4, 1 ： 16 and 1 ： 32 all exhibited additive effect against mycelial growth and conidium germination of C. gloeosporioides and C. capsici. While the 1 ： 8 mixture showed obviously synergistic interaction with SR of 1.98 and 1.93 to C. gloeosporioides, 1.95 and 2.11 to C. capsici, respectively.