多菌灵、多抗霉素及其复配对小麦赤霉病菌的生物活性研究

Study on Biological Activity of Carbendazim,Polyoxin and its Mixture against Wheat Fusarium graminearum

[目的]筛选多菌灵和多抗霉素对小麦赤霉病菌菌丝生长抑制效果最好的复配比例。[方法]在室内选用95%多菌灵和10%多抗霉素化学药剂进行复配,计算单剂和混剂对小麦赤霉病菌丝生长的抑制率、毒力曲线及其EC50值,研究其对小麦赤霉病菌复配效果,并选用共毒系数法来确定两种药剂的最佳混配比例。[结果]95%多菌灵和10%多抗霉素对Y73#菌菌丝生长的有效抑制中浓度EC50值分别为6.6和0.7μg/ml,表明四川省雅安生态区小麦赤霉病致病菌Y73#菌对多抗霉素比较敏感,而对多菌灵已经产生了抗药性;95%多菌灵和10%多抗霉素混配后表现出加相或增效作用,混剂中多菌灵含量为20%时,共毒系数最大,CTC值为243.5,表现出较强的增效作用。[结论]多菌灵和多抗霉素的最佳复配比例为1∶4。

[Objective] The study aimed to screen the ratio of the mixture of carbendazim and polyoxin that had best effect on controlling the mycelium growth of wheat Fusarium graminearum. [Method] The 95% Carbendazim and 10% Polyoxin were selected for the mixture and the inhibiting rate,virulene curve and EC50 value of the single agent and mixture agent on the mycelium growth of wheat F. graminearum were accounted to study their complex effect against F. graminearum. The the co-toxicity coefficient was selected to confirm the optimum complex ratio of 2 drugs [Result] When 95% carbendazim and 10% polyoxin were effective for inhibiting the mycelium growth of Y73# F. graminearum,their EC50 were 6.6 μg/ml and 0.7 μg/ml resp. showing that the polyoxin was more sensitive than arbendazim to Y73# F. graminearum and there had some resistance to carbendazim in Y73# F. graminearum in Ya＇an ecotope in Sichuan Province. 95% carbendazim mixed with 10% polyoxin had the efficacy of additive function or synergism. When the carbendazim was 20% in the mixture,the co-toxicity coefficient was biggest,being 243.5 mg/L,indicating a stronger synergism. [Conclusion] The optimum complex ratio of carbendazim and polyoxin was 1∶4.