Abstract: In order to comprehensively evaluate the resistance of tobacco varieties to M.incognita and select the disease resistance index, this study took 20 tobacco varieties as experimental material, measured their relative growth rate and relevant disease resistant indexes 60 d after artificial inoculation with M. incognita by seedling pot cultivation, and analyzed the test data by combining subordinate function with clustering analysis method. The results indicated that there were differences in relative growth rates and disease resistant indexes of 20 tobacco varieties infected by M.incognita. The result of clustering analysis on gall index was very similar to that of the other indexes, and there was less difference from that of clustering analysis on relative growth rates. The results of comprehensive identification on tobacco varieties gained from combining clustering analysis with subordinate function were consistent with the results of the other research method. Synthetically, the gall index can basically reflect the resistant level of tobacco varieties to M.incognita.

Key words: tobacco variety, M. incognita, disease resistance, subordinate function, clustering analysis

摘要： 为了综合评价烟草抗南方根结线虫的能力，筛选出抗病指标,以20份烟草品种为试验材料，采用盆栽培育烟草幼苗人工接种南方根结线虫的方法，测量供试烟草品种在接种60 d后相对生长量和有关抗性指标，利用隶属函数和聚类分析相结合的方法对试验数据进行分析。结果表明，20个烟草品种受到南方根结线虫侵染后各器官的相对生长量、有关抗性指标均有差异。相对于其他指标，根结指数、抗性综合指标的聚类结果最相似，与相对生长量综合指标的聚类结果差异性也较小；通过隶属函数和聚类分析相结合的方法对烟草品种进行综合鉴定的结果与其他研究结果相符。综合表明，根结指数可基本反映烟草品种抗南方根结线虫的水平。

关键词: 烟草品种, 南方根结线虫, 抗病性, 隶属函数, 聚类分析