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The pathogenicity difference of P.brassicae on cabbage were carried out under 7 different temperature and 6 different soil pH with the soil with the resting spore concentration of 1 × 108 spores/g in the soil.The disease condition was investigated after 90 days.The results showed that there here different infection rates of clubroot of cabbage among different temperature sets, the effect of temperature on the incidence of clubroot in descending order as follows: 30℃ >25℃ >20℃ > 35℃ > 15℃ > 10℃ >5℃under pH 6, the infection of clubroot was weak and the infection rate was low under the temperature value of 5℃ and 10℃.The disease rate increased with increasing soil temperature under the temperature value of 5 ~30℃, but decreased at 35℃, the infection rates of clubroot were 80.36%, 100%, 65%,10.77%, 3.23%, 0% under the soil pH 4, 5, 6, 7, 8 and 9 at 25℃, respectively, the growth of cabbage was inhibited and the survival rate was reduced under pH 4, the infection rates of clubroot were low under pH 7 and 8, and the infection rate of P.brassicae was 0% under pH 9.The Chinese cabbage grew better under pH of 5 and 6, but had the high infection rates of clubroot.The infection rate of clubroot was related to the temperature and soil pH closely.