Identification And Detection Of GLRaV And Reseach On Techniques Of Gapevine Viruses Elimination

Grapevine leafroll disease is the most devastating disease of grapevine in many grapeving producting areas, and the pathogens of it are more than one virus . In these viruses, grapevine leafroll associated virus 3 is the most important one , and it is the only one that has a nature transmission vector .It was investigated that the occurrence of GLRaV is more than 64 varieties and block grown in the east of Helan mountains, Ningxia . The results showed that no symptoms of GLRaV were found in the American species of Eavitis and Eastern Asian species of Eavitis while the highest percentage of infected varieties were found in V. vinifera. The results also showed that some hybrids of V.vinifera and other species had the symptom of GLRaV . In V. vinifera ,the Probes accidentalis and the Probes pantica had higher percentage of GLRaV infection than the Probes orientals. Moreover , infected grapevines are lower than healthy ones in chlorophyll content , photosynthesis and economic production, and fruit of GLRaV had less sugar and higher acide content. These resulted in a weak grapevine quality .Comparision of three ELISA methods for detection of GLRaV showed that DAS-ELISA,PTA-ELISA and PAS-ELISA could detect GLRaV and GFLV. DAS-ELISA could shorten the detection time. The techniques , however, have higher strain specificity and the false negatives can be caused . Therefore, PTA-ELISA and PAS-ELISA must repeatedly dectect some important samples.A series of broad spectrum media for stem tip tissue Virus- ree culture and propagation of grapevine was prepared. These media could shorten the culture time by 12?9 days as compared with the media used commonly. With heat treaement and stem tip tissue Virus梖ree culture, the survival rate of the plant and elimination rate of GLRaV increased more 10.9% and 9.2%, respectively, than singlar stem tip tissue Virus梖ree culture. Moreover, in the survival rate, the changable heat treatment increased more 12.4% than contant heat treatment while the elimination effect of the virus in grapevine showed little difference. The addition of WCT and FenYuanBao in medium exhibited the inhibitory effect on virus multipliction. It, however, had negative effect to the rate of plantlet.Activity of peroxidase (POD) was analyzed in leaves of grapevine after inoculation of GLRaV. The infection of GLRaV resulted in increase in activities of POD in the resistant and susceptible varieties, and activity of enzyme was significantly greater in resistant varieties than in susceptible ones. Moreover, analysis of POD isoenzyme showed that the number of enzyme bands in resistant varieties varied directly with symptom of plant while in susceptible ones ,varied versely with it,especially mid- late period.