The Relationship Between The Change Of Endogenous Jasmonic Acid In Rice And RGSV,RRSV

Rice grassy stunt virus(RGSV)and Rice ragged stunt virus(RRSV)are all transmitted by Brown rice planthopper(BPH)in a persistent and propagative manner.BPH is an important pest of rice,it can carry RGSV and RRSV then resulting in a potential threat to rice production.The experiment shows that BPH is prefer to eat rice that infected RGSV or RRSV than health rice when we inoculated virus.The research about synthesis of Jasmonic acid(JA)have been suggested that content and activity of JA can regulate insect resistance of plants.In this study,we are aim to explore whether the activity of JA changes because of the virus proteins that act on the gene of JA synthesis and signaling transduction,then deeply to affect the insect resistance.The experimental methods and results are as below.1.High performance liquid chromatography-mass spectrometry(HPLC-MS)was performed to figure out the difference in JA content in rice at tillering or booting stage.The results showed that JA accumulation in RGSV-infected rice decreased to 4 times when compared to that in healthy rice plants,while in RRSV-infected is 3 times,they have significant difference.2.Real-time qPCR were executed to detect the expression difference of genes related to the JA synthesis and signal pathway from RGSV,RRSV-infected rice and healthy rice.The findings indicated that the expression level of OsAOC,OsACX1 and OsJMTl down-regulated in RGSV,RRSV-infected rice was down-regulated and also the gene OsHPL3,which have the common substrate with JA synthesis.By contrast,the expression level of LOX,OsAOS and OPR gene family in RGSV and RRSV infected rice was higher than that in healthy rice.3.Assays in yeast two-hybrid system analyze the interaction between virus proteins and genes about synthesis of JA and signaling transduction.The results show the interaction between pGBK-P3 and pGAD-OsJMT1,also pGBK-OsJMT1 and pGAD-P3 in RGSV.Other genes also have interaction with JA synthesis genes.4.We plan to use rice genetic fast transformation system to get OsJMT1 transgenic rice plantsto do the BPH behavior experiments to further verify the relationship.This thesis only successfully constructed RNAi vectors and over-expression vectors of OsJMT1,now this experiment is taking root.Based on our experimental data,we can make sure that RGSV and RRSV can influence on the JA synthesis pathway,triggering changes in active JA level,and result in weakness of insect resistance.It preliminary laid the foundation for the molecular mechanism of insect resistance in RGSV and RRSV rice plants by influence JA activity.