Isolation and Identification of Pathogens Causing Rust Disease on Taraxacumkok-saghyz Rodin in Xinjiang

【Objective】 This project aims to identify the pathogen causing Taraxacumkok-saghyz Rodin rust disease and provide scientific basis for the effective control of the disease. 【Methods】 According to Koch's rule, the pathogen of rubber grass rust in the field was isolated and inoculated with healthy rubber grass to verify its pathogenicity. The morphology of summer spores of rubber grass rust was observed under the microscope. The 28S rDNA and its gene sequences of rust were amplified and sequenced by PCR with fungal universal primer NL1 / NL4 and rust universal primer ITS5-u/ITS4rust. The phylogenetic tree was constructed by its sequence to analyze the genus status of the strain. 【Result】 The rust isolated from field samples could infect healthy plants, and the symptoms were consistent with those in the field. The summer spores of rubber grass rust were nearly spherical, oval or ovoid, and the size was (24-32×21-26)μm, light yellow to chestnut brown, spiny, single cell, wall thickness of 1-2.5 μm. Its sequence genetic analysis showed that rubber grass rust in Ili, Xinjiang was the closest to Pucciniahieracii, and its sequence homology reached 99.06%. 【Conclusion】 The pathogen causing Taraxacumkok-saghyz Rodin rust disease was Pucciniahieracii.