Resistance Evaluation of Eggplant Root Stocks against Ralstonia solanacearum

Key words: 
• eggplant graft /
• root stock /
• solanacearum lanacearum /
• resistance

Abstract: Eggplant bacterial wilt（ Ralstonia solanacearum） is a major disease in eggplant（ Solanum melongena）,and selection of root stocks resistant to R. solanacearum is a better way to control this disease. Fifteen eggplant root stocks collected were grafted with the scions of eggplant variety Changfeng 2 to evaluate their resistance to R. solanacearum. The eggplant root stocks and their graftings were wounded in the root and inoculated with bacterial solution of R. solanacearum by drenching. Of all the eggplant root stocks,4（ Qing Lian 606,Qing Lian 605,Qing Lian 530 and Ding Qie） were found highly resistant,5 moderately resistant,2 susceptible,4 highly susceptible to R. solanacearum. In the eggplant plants grafted onto 15 root stocks,3（ Qinglian 530,Qing Lian 605 and Qing Lian 606） were highly resistant,2 resistant,5 moderately resistant,4（ such as Ding Qie） susceptible and 1 highly susceptible. Root stocks Qinglian 530,Qing Lian 605 and Qing Lian 606 which are local wild eggplants,and their graftings started to show disease symptoms 5 or 10 days after inoculation.Some of these plants displayed withered leaves at the early stage of disease infection. Their disease indexes were low after the disease turned stable. All of these root stocks and their graftings were highly tolerant. However,the other root stocks,highly susceptible or susceptible,and their graftings started to be infected with R. solanacearum 5 days after inoculation,and the bacterial wilt disease turned to be stable 60 days after inoculation.Their disease indexes were above 54. 44,and most of the plants died 70 days after inoculation. The root stocks Qinglian 530,Qinglian 605,Qinglian 606 and their graftings were highly resistant to R. solanacearum,and hence are promising materials for root stocks.