大白菜品种对软腐病抗性评价指标的研究

ESTABLISHMENT OF QUANTITATIVE CRITERIA FOR EVALUATING RESISTANCE OF CHINESE CABBAGE TO SOFT ROT

用8个品种测定了大白菜软腐病菌的根系侵入、潜伏侵染和伤口侵染,由此建立了品种抗性评价的3个指标,即根系侵染抗性、潜伏侵染抗性和伤口侵染抗性,以及属于这3个指标的7个参数。将不同品种在7个参数中的测定值从高到低(只一项为从低到高)分别划分为5个数值范围,并相应地记为1～5分,以表明品种抗性从弱到强的差别;以得分总和作为品种抗病性的综合定量指标。由此将8个品种分为综合抗性强、中、弱3组,其中以品种81-5和福山包头综合抗性最强,品种青石最弱。

Eight cultivars of Chinese cabbage were tested for their root invasion, latent infection, and wound infection by Erwinia carotovora subsp. carotovora, the pathogen of soft rot disease, in the lab and fields. Three criteria with 7 parameters were established for evaluating the cultivar resistance to the disease, and expressed as resistance to root invasion, to latent infection and to wound infection resp. The measured values of the seven parameters were separately divided into 5 grades from higher to lower (only one was opposite), and scored from 1 to 5 so as to indicate the relative resistance of cultivars. The total score value of each cultivar was functioned as a quantitative and comprehensive criterium of resistance to the disease. In term of comprehensive resistance, the tested cultivars were divided into 3 groups, i.e., resistant, middle-resistant, and susceptible. The cultivars 81-5 and Fushan were the most resistant, while Qingshi was the most susceptible.