贵州香蕉炭疽病病原菌的分离鉴定与防治药剂筛选OA

[Objective]The species of pathogenic strains causing banana anthracnose were investigated to screen effective chemical fungicides for controlling banana anthracnose and realize scientific and precise application of fungicides for guaranteeing economic benefits and sustainable development of banana industry.[Method]The morphological characteristics,pathogenicity and species of the purified stain causing banana anthracnose isolated from the suspected banana anthracnose leaves collected from four banana producing areas(Ceheng County,Wangmo County,Anlong County and Xingyi City)in Guizhou were analyzed,verified and identified by observation,Koch's law and molecular biology respectively.The indoor toxicity and controlling efficacy of 50%carbendazim WP,25%myclobutanil EC and 75%trifloxystrobin •tebuconazole WDG against the purified stain causing banana anthracnose were detected by the mycelial growth rate method.[Result]The strain GZXY012 was successfully isolated from the suspected banana anthracnose leaves and identified as Colletotrichum fructicola by morphology and molecular biology.There was a significant difference in inhibitory effect against C.fructicola among 8 tested fungicides,including 50%carbendazim WP,75%trifloxystrobin•tebuconazole WDG,25%myclobutanil EC and 80%mancozeb WP,etc.The EC50 of 45%prochloraz EW,50%carbendazim WP and 70%thiophanate-methyl WP was 0.095 μg/mL,0.176 μg/mL and 1.343 μg/mL respectively.The EC50 of 25%pyraclostrobine SC,10%difenoconazole M and 75%trifloxystrobin •tebuconazole WDG was 4.648-6.416 μg/mL.The EC50 of 25%Myclobutanil EC and 80%Mancozeb WP was 24.713 μg/mL and 91.332 μg/mL.The control effect of 6 tested fungicides×500 times against C.fructicola was 45%prochloraz EW(94.44%)＞50%carbendazim WP(92.22%)=10%difenoconazole M(92.22%)＞75%trifloxystrobin •tebuconazole WDG(88.89%)＞70%thiophanate-methyl WP(86.66%)＞25%pyraclostrobine SC(85.56%).[Conclusion]C.fructicola is one of main pathogens causing anthracnose in Guizhou's banana-growing regions.Three fungicides of prochloraz,carbendazim and difenoconazole with a good control effect against C.fructicola causing banana anthracnose should be used in banana production in Guizhou.