The Relationship Between JA、ETH And Resistance To Rhizomania In Sugar Beet

The plant endogenous JA and ETH can response the interaction between the plant and pathogen, these have been most widespread concerned, this tests were take aboratory simμLation field cμltivation conditions, to resistance and susceptiable sugar beet varieties as tested materials, study on the changes and discrepancy of the difference among species, in order to study the endogenous JA, ETH synthesis, IAA receptor gene, and downstream defense enzymes and some external index and resistant to rhizomnia relationship in resisitance and susceptiable variarties after beet necrotic yellow vein necrosis vius (BNYVV) infection.to explore the relationship between BNYVV and JA、ETH synthesis level, TIR1expression downstream defense enzymes and some external index. The results show as follow:1.Using western blotting to detect BNYVV relative contents in sugar beet. the ages of25to40days is the larger period of BNYVV infection and accumulated, this period can be used as the best period of detection the relationship between beet endogenous JA, ETH and resistance to disease.2.After BNYVV infection, LOX and AOS (JA synthesis key enzymes) activity was significantly enhance in resistant and susceptible varieties, APX and GR activities are enhance than not infected,and the activities resistant higher than susceptible varieties. ACC oxidase and ACC synthetase(ETH synthesis key enzymes) activity are also significantly increased, and the activities susceptible higher than resistant varieties,the enhance quantity of AOS,LOX,ACS,ACO,APX,GR activities have a positive correlation with BNYVV relative contents.3. After seed soaked by JA treatment, endogenous JA synthetase (LOX and AOS) activity increased, ETH synthetase (ACS and ACO)activity was inhibited, disease index decreased, and TIR1expression appreciably increased, APX and GR (disease-resistant enzyme) activity is also increased, the value of SPAD leaves have a little increase4.Take RT-PCR to detect TIR1gene expression, TIR1gene expression have a certain relationship with BNYVV, and grow from seed soaked by JA have a little enhance on the TIR1gene expression.All in all, JA could inhibit the infection of BNYVV in sugarbeet root, and seeds soaking with JA coμLd be through improve LOX and AOS activity that key enzymes of JA synthesis, ACS and ACO activity and stimulate the increased expression of TIRl to enhance the resistance of plant. This research elaborates the effect of JA and ETH in sugar beet Rhizomania, provide the theory basis to sugar beet resistance mechanism and breeding disease-resistant varieties, and these can provide a reference for make new measures to regulate resistance to rhizomnia.