Effect Of Tagitinin A On TSWV Genes Replication And Its Field Application Experiment

Tomato spotted wilt virus is a representative species of the Orthotospovirus genus,which can infect various crops such as tomato,tobacco,and pepper and cause seriously economic losses to agricultura every year.The previous study have found that Tagitin A(Tag A)which was extracted from Tithonia Diversifolia could inhibit TSWV infection by inducing jasmonic acid(JA)pathway.On the basis of previous research,our study analysed the Tag A inhibited TSWV gene replication through VIGS and overexpressing of the key gene acyl coenzyme A oxidase(ACX)which was JA pathway synthesized gene.The results have been obtained as follows:(1)TSWV was inhibited by Tag A.The experiments of protecition and curtion were conducted and the cultivated tobacco K326 as materials,the samples of inoculated leaves were taken at 1dpi,3dpi,5dpi,and 7dpi for ID-ELISA detection.The results showed that the levels of TSWV were lower in the control and prevention experiments compared to the positive control group;at the same time,q RT-PCR was used to detect the expression level of TSWV N gene.The results showed that the treated samples compared with the positive control,TSWV N gene replication was delayed 2dpi in the inoculated leaves.In the protecition experiment,TSWV N gene replication was not delayed,but significantly lower than the positive control.The above results indicated that greenhouse cultivation experiments further verifing that Tag A inhibit the TSWV infection.(2)Tag A inhibits the replication of TSWV-NSm and NSs genes by inducing the ACX gene of JA synthesis pathway.The key gene ACX synthesized through the VIGS silencing and overexpression JA pathway was used to detect the changes in gene replication of the motion protein NSm(NSm)and silencing suppressor NSs(NSs)of TSWV using q RT-PCR.The results showed that the gene replication of TSWV NSm and NSs was significantly higher than that of the positive control after the ACX gene was silenced;after overexpression of the ACX gene,the replication of TSWV-NSm and NSs genes was significantly lower than that of the positive control.The results showed that Tag A inhibited the replication of TSWV-NSm and NSs genes by inducing the JA synthesis pathway ACX gene;(3)Tag A could inhibit TSWV infection and increase yield is higher than Ningnanmycin in the field experiment.The field experiment was conducted with dimethyl sulfoxide(DMSO)as the negative control,ningnanmycin as the control agent,and Tag A as the treatment group.The results showed that the incidence rate after treatment with Tag A was 11.67%,and the relative control effect was 46.15%,lower than that of the control agent.In summary,Tag A inhibits the replication of TSWV-NSm and NSs genes by inducing the JA synthesis pathway ACX genes,and has certain field application value,It provides theoretical basis and lead compound for field green prevention and control of TSWV.