陕西省大白菜黑腐病苗期人工接种抗性鉴定方法研究

Study on Resistance Identification Method of Black Rot at Seedling Stage of Chinese Cabbage in Shaanxi Province

为给大白菜抗黑腐病的新品种选育和种质创新提供技术保障,以陕西省大白菜主产区致病力强的黑腐病病菌株YL-17做菌源,以4个不同抗病性的大白菜品种为试材,研究了苗龄、接种浓度和发病温度对抗病性鉴定的影响,建立了优化的大白菜黑腐病苗期人工接种鉴定方法,即接种方法采用喷雾法,接种菌量为1.0×10^8pfu/mL,接种时期为4-5叶期,发病温度控制26℃。该方法鉴定结果准确可靠,能客观反映不同大白菜品种的抗病性能。

In order to provide a technical support for breeding new varieties and germplasm innovation of Chinese cabbage （Brassica campestris L. ssp penkinsis ）with resistance to black rot, the representative Chinese cabbage leaves of black rot were collected in central Chinese cabbage fields of Shaanxi province, then the pathogen bacterium （Xanthomonas campestris pv. campestris （Pam.） Dowson,） was separated, purified and classified according to its morphologic characteristics and Koch＇postulates, the bacterium strian YL-17 , which has strongest infection capacity in 35 representative bacterium strains, was selected and used in resistance inoculation, by comparing the effects of seedling stage, temperature and concentration of bacterium on the disease identification. The optimizing artificial inoculation method for black rot identification were set up, which key procedure is praying bacterium liquor of 1×10^8 pfu/mL on seedling with 4-5 true leaves stage, and keeping at 26℃. its results was effective and exact and was in accordance with the resistance type of different Chinese cabbage.