Rapid Detection Plasmopara Viticola By Molecular Methods

Grape (Vitis L.), one of the most important fruit in the world, is becoming more and more valuableand widely planted in China, and grape industry is an important part of agriculture and socio-ecnomicdevelopment in some countries. Grape downy mildew was first noted in France in1870s with theintroduction of rootstocks resistant to phylloxera of American wide grape species, then graduallyspread throughout the world, has resulted in disasters for many times. The disease was highlydestructive to vines and had significant impact on the healthy development of grape industry. Since theinvention of Bordeaux mixture in1882, chemical control is always the main method to control grapedowny mildew. However, applying fungicides for many times will increase the risk of pesticides.Prediction and forecasting is the key to successfully control grape downy mildew, precisely applyfungicides and finally reduce risks of pesticides application. Therefore, developing methods ofprediction and forecasting are of great significances to successfully control this disease. Moleculardetection methods can provide molecular basises for accurate prediction and forecasting. At present,there are hardly any reports on the detection of Plasmopara viticola by rapid molecular methods.In this study, two molecular detection methods of P. viticola with features of high efficiency,rapidity, specificity and sensitivity were explored and established in order to provide molecular basisesfor timely and accurate prediction and forecasting of grape downy mildew. The results were as follows:1. A rapid LAMP detection method of P. viticola with high specificity was successfully established.This method can successfully detected33fg/μl genomic DNA of P. viticola in just55min and thesensitivity of it was100times than conventional PCR.2. A Padlock Probe with high specificity was developed and a PLP detection method for P. viticolawas explored and preliminarily established. The detection limit was9.4pg/μl. The PLP and thedetection method for P. viticola will lay a solid foundation for the development of combined detectiontechnology for many grape pathogens in the future.3. Genomic DNA of78samples were extracted by a rapid DNA extraction method and tested byLAMP and PLP methods. The results showed that all samples infected by P. viticola could besuccessfully detected wherever they were from and whatever varieties they were on.