1Institute of Vegetables and Flowers，Chinese Academy of Agricultural Sciences，Beijing 100081，China；2Microbiology Institute of Chinese Academy of Sciences，Beijing 100101，China
Abstract：In 2011，the disease known as‘base stem rot’of Chinese cabbage〔Brassica campestris L. ssp. pekinensis（Lour）Olsson〕was prevalent in Beijing，Hebei and Jiangsu Provinces．12 fungi isolates were collected from rotten stem of Chinese cabbage．The morphological identification show the isolated bacteria strain is Rhizoctonia solani．PCR of rDNA-ITS was propagated by general primer ITS1/ITS4 and the sequencing result was compared and analyzed in GenBank．The results of molecular identification and morphological identification were the same．Then the isolated bacteria strains were inoculated to the healthy Chinese cabbage stems．The symptoms resembled the ones originally observed in the fields．Finally，the pathogen’s identity was confirmed by re-isolation from lesions of infected plants．Based on the tests of morphological characteristics，pathogenicity and molecular biology，the pathogens of Chinese cabbage‘base stem rot’found in Beijing，Hebei and Jiangsu Provinces were the same as brown rot，Rhizoctonia solani．etc.
