The Relationship Between Inducible Expression Of Defense Response Gene And Enzyme Activities With Rhizomania In Suger Beet

Sugar beet rhizomania is a global soil-borne disease caused by beet necrotic yellow vein virus, it causes great harm to sugar beet industry and production.The relationship between different cultivars of sugar beet gene expression and activity of olyphenol oxidase(PPO),Peroxidaseisozyme(POD),Super oxidedismutaseh(SOD),Phe-nylalanineammonialyase(PAL),Lipoxygenase(LOX) in sugar beet leaves and roots with sugar beet rhizomania were studied in Potted(diseased and non-diseased soil) and hydroponics cultivation conditions by using a method of RT-PCR and comparative physiology to in this study.This research produced from the relationship between the defense response gene transcript levels respects and activities of defense reaction enzymes, provides a theoretical basis to the sugar beet physiological and disease resistance breeding.The main results were as followed:1. This study make a detection to beet necrotic yellow vein virus by using RT-PCR method, get better amplified bands, the target fragment size is 324bp.2. Make an optimization to the RT-PCR system for get a better amplified bands, the concentration of primer is 0.4uMol/L,dNTPs is 0.1mMol/L、Taq enzyme is 0.2U/uL、Mg2+is 1.5mMol/L. PCR amplification using a three-step method, annealing temperature is 55 ℃ and 30s; Denaturation temperature is 95 ℃ and 30s;Srength temperature is 72℃ and 30s,45 cycles.3. Under the soil cultivations,resistant cultivars sugar beet leaves and roots have same variation activities of olyphenol oxidase(PPO),Peroxidaseisozyme(POD),Super oxidedismutase(SOD),Phenylalanineammonialyase(PAL),Lipoxygenase(LOX) compa re with susceptible sugar beet cultivars in different growth period (P<0.05).There have higher enzyme activities on the diseased soil than non-diseased, it shows that pathogen infection induced the content of Rhizomania substances and related defense enzymes increased.4. Under the hydroponic cultivation conditions, there have significant difference of olyphenooxidase(PPO), Peroxidaseisozyme(POD), Superoxidedismutase(SOD),Ph enylalanine ammonialyase(PAL), Lipoxygenase(LOX) activities after disease stress with the soil cultivation conditions (P<0.05). It has a bit expression of defense response genes in sugar beet with different disease resistance before unaffected the rhizomania, different varieties has Varying degrees inducible expression from the 35d,the expression of various defense response genes of the resistant varieties were earlier and strong expression than the susceptible ones. Those genes inducible expression has close relationship with Beet resistance, beet necrotic yellow vein virus can stresses and induces the Beet defense genes different levels of expression in beet varieties, then effective activate the different defense response system.