The Research On The Control Effect And Mechanism Of Rhodopseudomonas Palustris PSB-06 On Tomato Chlorosis Virus

Tomato chlorosis virus(ToCV)is one of the tomato viruses widely distributed in the world.In recent years,it has been widely transmitted in most parts of China,causing serious losses to tomato production.It is mainly transmitted by Bemisia tabaci in a semi-persistent and non-circular manner.Trialeurodes vaporariorum is also the vector of ToCV.Studying the transmission characteristics of different vectors can provide a theoretical basis for the prevention and control of ToCV.Rhodopseudomonas palustris PSB-06 are prokaryotic organisms with an original light synthesis system.They are rich in nutrients such as protein,vitamins,growth-promoting factors,and immune factors.They can improve the disease resistance of plants.Studying the mechanism of rhodopseudomonas palustris PSB-06 on ToCV can provide a theoretical basis for the prevention and management of ToCV.In this study we found that both B.tabaci and T.abutilonea existed in Inner Mongolia and Guizhou.Therefore,the occurrence of different whiteflies and their impact on the spread of ToCV were investigated.At the same time,the effect of rhodopseudomonas palustris PSB-06 treatment on the occurrence of ToCV was studied.Then the mechanism of the action of photosynthetic bacteria on ToCV was analyzed from the perspective of plant defense and plant nutrition.The main results are as follows:1.The occurrence of ToCV in Chifeng City,Inner Mongolia Autonomous region and Guiyang City,Guizhou province,as well as the number of Bemisia tabaci Q and Trialeurodes vaporariorum on tomato plants were investigated.The results showed that in Chifeng city there was a high tomato infection rate,and the number of B.tabaci Q was high.The virus acquisition and transmission of T.vaporariorum and B.tabaci Q was compared and the results showed that the ability of B.tabaci Q to acquire and transmit virus is significantly higher than that of T.vaporariorum.It indicates that the spread of ToCV is mainly through B.tabaci Q.With the increase of the number of B.tabaci Q,the incidence of ToCV will increase.2.The effects of different treatments on the occurrence of ToCV were compared by spraying rhodopseudomonas palustris PSB-06,5%aminooligosaccharin and water in the field.The results showed that the tomato treated with rhodopseudomonas palustris PSB-06 showed the lowest incidence of ToCV,with the number of 57.10%,and the relative control effect against ToCV was 64.38%,indicating that rhodopseudomonas palustris PSB-06 had a good inhibitory effect on ToCV.3.The effects of rhodopseudomonas palustris PSB-06 treatment on the gene expression and content of plant defense hormones jasmonic acid(JA)and salicylic acid(SA)of tomato were compared using plants infected with ToCV-infected and healthy plants.The results showed that within 1-6 days after rhodopseudomonas palustris PSB-06 treatment,in tomato plants infected with ToCV,the expression of JA-related gene PI II gradually decreased,while the expression of SA-related gene NPR1 gradually increased;in healthy tomatoes,the expression levels of JA and SA in the plants were gradually increased.The content of JA and SA in tomato plants after treatment was detected,and results showed that the content of JA in healthy tomato plants treated with rhodopseudomonas palustris PSB-06 was higher,and the tomato plants infected with ToCV did not change much;after treatment with rhodopseudomonas palustris PSB-06,the SA content of healthy and ToCV-infected tomato plants increased significantly,indicating that rhodopseudomonas palustris PSB-06 treatment can induce plant defense mainly by inducing the SA signalling pathway.4.In healthy and ToCV-infected tomato plants,the plant nutrition treated with rhodopseudomonas palustris PSB-06 was higher than that of plants treated with water,indicating that rhodopseudomonas palustris PSB-06 treatment can promote the growth and development of tomato plants.After spraying rhodopseudomonas palustris PSB-06 on ToCV-infected tomatoes,the number of B.tabaci Q on tomato plants was counted after 24,48 and 72 h.In the observed 24-72 h,B.tabaci Q preferred tomato plants treated with water.