丙硫菌唑与5种常用杀菌剂复配对水稻、小麦纹枯病菌的联合毒力

Combined Virulence of the Mixtures of Prothioconazole with Five Kinds of Commonly Used Fungicides to Rhizoctonia solani and Rhizoctonia cerealis

为明确丙硫菌唑与5种常用药剂的复配潜力,笔者采用菌落生长抑制法,测定丙硫菌唑与各杀菌剂不同配比对水稻、小麦纹枯病菌的联合毒力。结果表明,丙硫菌唑单剂对水稻、小麦纹枯病菌的EC_(50)值分别为2.2025μg/mL和3.4162μg/mL,其他几种杀菌剂单剂的EC_(50)值则在0.0347~1.7922μg/mL和0.0670~1.4463μg/mL。将丙硫菌唑与各药剂分别按3∶1、2∶1、1∶1、1∶2和1∶3的比例复配后,对于小麦纹枯病菌来说,以丙硫菌唑与氟环唑复配增效最为明显,2∶1配比下最大SR值可达6.69;对于水稻纹枯病菌,则以丙硫菌唑与吡唑醚菌酯3∶1复配联合毒力最强,SR值为1.92;丙硫菌唑与咯菌腈复配效果最差,各配比下对水稻、小麦纹枯病菌的SR值均小于1.0,说明除咯菌腈外,丙硫菌唑具有与多种杀菌剂复配,并进一步研发成制剂的潜力。

In order to determine the mixing potentiality of prothioconazole with five kinds of fungicides used to control rice sheath blight and wheat sharp eyespot in field,EC_(50) values of these mixtures were tested by the colony growth inhibition method.Results showed that the EC_(50) values of prothioconazole for R.solani and R.cerealis were 2.2025μg/mL and 3.4162μg/mL,while other fungicides for R.solani and R.cerealis were from 0.0347μg/mL to 1.7922μg/mL and from 0.0670μg/mL to 1.4463μg/mL,respectively.When prothioconazole was mixed with each fungicide at the ratios of 3∶1,2∶1,1∶1,1∶2 and 1∶3,the mixtures of prothioconazole and epoxiconazole had the highest combined virulence and showed obvious synergistic effect at each ratio,and the maximum SR value reached 6.69 at the ratio of 2∶1.When prothioconazole and pyraclostrobine were mixed at the ratio 3∶1,the mixture had the highest combined virulence to R.solani and the SR value was 1.92.The mixtures of prothioconazole and fludioxonil had lower virulence to R.solani and R.cerealis,and all the SR values were less than 1.0.All above showed that prothioconazole could be used to mix with several fungicides and these mixtures had the potential to be further developed into formulations.