Screening Clubroot-resistant Germplasm Resources from 20 Brassica napus Varieties

Simulated root disease conditions,twenty varieties of rape(Brassica napus) varieties inoculated with infested soil of fungi in pots were cultured for identifying the root disease resistance.According to the disease index,the 20 rape varieties were divided into five groups:high resistant,resistant, low sensitive, middle sensitive and high sensitive.The disease index of Huaza 9 and Huashuang 3 were 25.06 and 25.03,respectively, so they belonged to high resistant varieties. The disease index of Yunhuayouzaoshu 1 and Shanyou 8 were 34.6 and 36.92 respectively,belonged to resistant varieties.The disease index of Zhongshuang 9,Huayou 5 and Huayou 8 were 45.8,46.89 and 47.33,respectively,belonged to low sensitive varieties.Yuhongyou 2 and other four varieties belonged to middle sensitive varieties.Ningyou 16 and other seven varieties belonged to high sensitivity varieties.Huaza 9 and Huashuang 3 showed high resistance and could be used as clubroot-resistant breeding for further study.