Research on the isolation and identification of black spot disease of Rosachinensis in Kunming, China

Through a survey of rose diseases in the South Tropical Garden in Kunming, China, it was found that black spot was the most common and serious disease of rose cultivated in the open air there, with an incidence of more than 90%. In this study, fungus isolation was performed on leaf samples of five black spot susceptible varieties of rose from the South Tropical Garden by tissue isolation. 18 strains of fungus were initially obtained, and seven of them were finally identified to cause black spot symptoms on healthy leaves of rose after verification by Koch's rule. By observing the morphology of colonies and spores, and constructing a phylogenetic tree by combining molecular biology and multiple genes, two pathogenic fungus were identified, namely, Alternariaalternata and Gnomoniopsisrosae.G.rosae was the first pathogenic fungi of rose black spot isolated and identified in this study. The results of this study can provide a reference base for further research and control of the black spot disease of rose in Kunming.

Automated summary

A survey of rose diseases in the South Tropical Garden in Kunming, China revealed that black spot was the most common and serious disease of rose cultivated in the open air, with an incidence rate of over 90%. This study isolated fungi from leaf samples of five black spot susceptible varieties of rose and identified two pathogenic fungi, Alternaria alternata and Gnomoniopsis rosae, through colony and spore morphology observation and molecular biology analysis. G. rosae was isolated and identified as a pathogenic fungus of rose black spot for the first time in this study. The results of this study can serve as a reference for further research and control of black spot disease in Kunming.