Identification of Colocasia esculenta(L.) Schott var. Lipu Taro leaf blight disease causal pathogen and its protoplasts preparation

ObjectiveThe present study was conducted to identify the causal pathogen of taro leaf blight disease by using morphology and molecular methods , and establish a protoplast preparation protocol , in order to provide scientific basis for pathogen detection of taro leaf blight, pathogenesis and virus-free and healthy seedling production. MethodThe samples were collected from taro production area in Lipu county, Guangxi. The pathogen was isolated, and identified through morphological examination combined with rDNA-ITS sequence analysis. Protoplast of pathogen was prepared by enzymatic digestion.ResultThe taro leaf blight pathogen was preliminarily identified as Phytophthora colocasiae based on its morphological characteristics and pathogenicity test. The results of rDNA-ITS sequence analysis indicated that the nucleotide sequence of the isolate was 99% similar to the isolates of P. colocasiae strains available in GenBank , which confirmed further that the isolate was P. colocasiae. Furthermore , the prepared protoplasts of P. colocasiae were circular or nearly circular, small or large, transparent.ConclusionThe causal pathogen of taro leaf blight in Lipu of Guangxi is identified as P. colocasiae and its prepared protoplast could be used for pathogenesis study of taro leaf blight disease.