Study on the resistance to black spot disease of pear germplasm

The resistance to black spot disease of 368 pear genetic resources, including 5 species of Pyrus Linn, were studied in the field conditions in the national sand-pear repository at Wuhan, Hubei province, 35 accessions were evaluated by artificial inoculation. The results showed that the P. betulaefolia Bge was the strongest one and P. communis L weakest one. Resistant indexes (0%) of district clones of sandpear were: Guangdong pear 10.42、Fujian pear 12.50、Hunan pear 18.33、Guangxi pear 21.53、Zhejiang pear 21.82、Guizhou pear 27.50、Sichuan pear 23.68、Yunnan pear 23.81、Hubei pear 24.53、Japanese pear 25.00 and Jiangxi pear 27.50. 1 high resistant 8 resistant varieties or clones were identified by artificial inoculation.