Study On The Effects Of An Avirulent Strain Of Ralstonia Solanacearum-GFP On Suppressing Bacterial Wilt Disease In The Tomato

The Bacterial Wilt Disease (BWD) is a fatal bacterial disease caused by Ralstonia solanacearum, which distributes widely in tropic, semitropics and temperate zones. R. solanacearum can invade several hundred plant species of at least 44 different families, and it has led to a great economic losing in agriculture. It has attracted lots of attention on the biocontrol of BWD. The study including the comparison of the colony morphology and single cell morphology of GFP-Rs-L.1.3-020626-1A and Rs-L.1.3- 020626-1A, the best infection system of GFP-Rs-L.1.3-020626-1A on tissue cultured tomatoes, effect of GFP-Rs-L.1.3-020626-1A on the control of tissue cultured tomatoes and preliminary study of the effect of GFP-Rs-L.1.3-020626-1A on the control of potted tomato seedlings.The results indicated that when GFP-Rs-L.1.3-020626-1A inoculated tissue cultured tomatoes by root-injuring with concentration of 104cfu/mL, effect of infection was the best. This system would be used in future studies. The content of GFP-Rs-L.1.3-020626-1A in tissue cultured tomatoes was constantly increasing. Time of roof-submerging didn't affect the content of GFP-Rs-L.1.3-020626-1A in potted tomato seedlings. The content of GFP-Rs-L.1.3-020626-1A in potted tomato seedlings was far less than the content in tissue cultured tomatoes.GFP-Rs-L.1.3-020626-1A was very effective to delay the BWD and reduce the wilt rate. When tissue cultured tomatoes were inoculated by mixture of GFP-Rs-L.1.3-020626-1A and Rs-F.1.2-010618-07V, the BWD delayed. When the 104cfu/mL GFP-Rs-L.1.3-020626-1A and the 104cfu/mL Rs-F.1.2-010618- 07V mixed 1∶1, tissue cultured tomatoes began to wilt 8d after inoculated, 3d later than the control. When Rs-F.1.2-010618-07V inoculated earlier than GFP-Rs-L.1.3- 020626-1A or at the same time, the BWD delayed and the wilt rate didn't reduced. When GFP-Rs-L.1.3-020626-1A inoculated earlier than Rs-F.1.2-010618-07V, the BWD delayed and the wilt rate reduced. When GFP-Rs-L.1.3-020626-1A inoculated 4d earlier than Rs-F.1.2-010618-07V, tissue cultured tomatoes began to wilt 11d after inoculated, 7d later than the control. When GFP-Rs-L.1.3-020626-1A inoculated 5d earlier than Rs-F.1.2-010618-07V, the wilt rate reduced to 6.52%, far less than the control group. When potted tomato seedlings inoculated by GFP-Rs-L.1.3-020626-1A ,the wilt rate reduced to 36.7%,compared 73.3% as control group.