月季枯枝病病原物鉴定、生物学特性与防治药剂筛选OA

[Objective]This study aimed to identify the causal pathogen of branch blight in Rosa chinensis,characterize its biological properties,and evaluate effective fungicides to establish a scientific foundation for disease for disease control.[Method]The pathogen was isolated and purified using tissue isolation.The isolate was characterized morphologically and phylogenetically by multi-locus sequence analysis.Mycelial growth kinetics were assessed under varying carbon/nitrogen sources,pH values,and temperatures using the growth rate method.5 fungicides were evaluated for inhibitory effects by poisoned medium technique.[Result]The purified strain R1007 induced disease symptoms upon wound inoculation,and the same strain was re-isolated from infected tissues.Morphological characteristics matched Nectria ulmicola,and Blast analysis with p hylogenetic analysis confirmed high genetic similarity to the type strain CFCC52117 of N.ulmicola.Optimal growth conditions were maltose(carbon source),yeast extract(nitrogen source),pH 7.17,and 25℃.Among tested fungicides,carbendazim showed the strongest inhibition(EC50=0.338 8 mg·L-1).[Conclusion]The causal agent of R.chinensis branch blight was identified as N.ulmicola.The optimal growth conditions were maltose and yeast extract as carbon and nitrogen sources,pH 7.17,and 25℃.Carbendazim shows promise as an effective fungicide for disease control.[Ch,5 fig.2 tab.28 ref.]