Occurrence and strain differentiation on turnip mosaic potyvirus and sources of resistance in Chinese cabbage in China

摘要

After extensive studies on 94 cruciferous plant species, a set of new differentiation hosts consisting of six cruciferous vegetable varieties was established. Nineteen major isolates of turnip mosaic potyvirus (TuMV) selected out of 5739 samples from 10 cities or provinces in China were examined. They fell into 7 strain groups based on the reaction in the 6 differential hosts. Sixteen hybridoma cell lines secreting monoclonal antibodies reactive to various strains of TuMV were established. The results of serological reactions were compared with the reaction on the new set of differential hosts. Of more than 3000 Chinese cabbage (Brassica rapa vars. pekinensis [B. pekinensis] and chinensis [B. chinensis]) germplasm accessions systematically examined with the 19 TuMV major isolates, 8 were immune or highly resistant to all TuMV isolates in the 7 strain groups. Breeding programmes utilizing TuMV-resistant germplasm from the collection resulted in release of 28 new resistant cultivars grown on more than 300 000 ha in China.