丙硫菌唑和氟唑菌酰羟胺复配对小麦赤霉病菌的联合毒力

Combined virulence of prothioconazole and fluazole hydroxylamine compounds against fusarium head blight

为探明丙硫菌唑、氟唑菌酰羟胺对禾谷镰刀菌引起的小麦赤霉病的联合毒力。本研究采用菌丝生长速率法,测定丙硫唑菌和氟唑菌酰羟胺对禾谷镰刀菌的室内生物活性,确定丙硫菌唑和氟唑菌酰羟胺防治小麦赤霉病的最佳复配比例。结果表明,丙硫菌唑、氟唑菌酰羟胺对小麦赤霉病菌的EC_(50)分别为22.44、0.33 mg·L^(-1)。在丙硫菌唑和氟唑菌酰羟胺的3个不同配比中,2∶3配比时EC_(50)最小,为0.19 mg·L^(-1);1∶1配比时EC_(50)值最大,为0.47 mg·L^(-1)。丙硫菌唑和氟唑菌酰羟胺质量比为1∶1、2∶3和1∶2的共毒系数分别为137.54、285.91、175.36。综合增效作用考虑,丙硫菌唑和氟唑菌酰羟胺以2∶3混配效果最佳。结果表明,50%丙硫菌唑·氟唑菌酰羟胺悬浮剂300、400、500 mL·hm^(-2)施药25 d对小麦赤霉病的防治效果分别为91.76%、97.03%、99.77%,防治效果突出。50%丙硫菌唑·氟唑菌酰羟胺悬浮剂可以防治小麦赤霉病,在小麦赤霉病发生初期使用,施药2次,2次施药间隔10~15 d。

The purpose of this study was to investigate the combined virulence of prothioconazole and fluazole hydroxylamine against fusarium head blight caused by Fusarium graminearum.In this study,the mycelial growth rate method was used to determine the indoor biological activity of prothioconazole and fluazole acylhydroxylamine against Fusarium graminearum,and to determine the optimal ratio of prothioconazole and fluazole acylhydroxylamine for the control of fusarium head blight.The results showed that the EC_(50)levels of prothioconazole and fluazole acylhydroxylamine against fusarium head blight were 22.44 and 0.33 mg·L^(-1).Among the three different ratios of prothioconazole and fluazole hydroxylamine,the EC_(50)was the smallest at 2∶3,which was 0.19 mg·L^(-1).The EC_(50)value was the highest at 1∶1 ratio,which was 0.47 mg·L^(-1).The results showed that the co-toxicity coefficients of prothioconazole and fluazole hydroxylamine were 137.54,285.91 and 175.36,respectively,with the weight ratios of 1∶1,2∶3 and 1∶2,respectively.All things considered,the best blending effect of prothioconazole and fluazole hydroxylamine at 2∶3 was the best.The control efficacy of 300,400 and 500 mL·hm^(-2)of 50%prothioconazole fluazole hydroxylamine suspension on fusarium head blight was 91.76%,97.03%and 99.77%,respectively,after 25 days.50%prothioconazole fluazole hydroxylamine suspension can prevent and control fusarium head blight,which is used in the early stage of fusarium head blight,applied twice,and the interval between the two applications is about 10-15 days.