Abstract:

【Objective】 In order to screen the resistant tomato rootstocks, the screening method and the resistance to Meloidogyne incognita were studied in the experiment. 【Method】 The relative growth rate and relevant disease resistant index of 16 tomato rootstock seedlings planted in pots and inoculated with M. incognita were measured after 50 days, moreover cluster analysis and subordinate function were used in the experiment. 【Result】 The results showed that different relative growth rates of different organs, different disease resistant indexes of 16 tomato rootstock seedlings and their different coefficient variances resulted from the infection of M. incognita were different, in which the coefficient variances of relative root fresh mass of five relative growth rate was 20.20%, the highest, but that of relative stem diameter was only 6.22%. The results of clustering analysis with the relative growth rate and the disease resistant index were same as GI, but be a little different from the results of clustering analysis with DI. By the method of subordinate function, the sequence of resistance from strong to weak successively was determined.【Conclusion】 The result of cluster analysis with multiple indexes and total indexes was more accurate than other single index for the resistant class of tomato rootstocks to M. incognita. By the method of clustering analysis and subordinate function, Baliya is determined as an immune material; BESUPA, Banzhen No.2, Rootstock 606, Rootstock002, Rootstock001, TMS-150, SUPPORT, MIKADO, Rootstock 401 are resistant materials; Anka-T is a disease tolerant material; Banzhen No.1 and Beijing No.1 are sensitive materials; 128, BF xingjing 101, and LS-89 are highly sensitive materials.

Key words: tomato rootstock, Meloidogyne incognita, relative growth rate, disease resistant index, clustering analysis, subordinate function analysis