Investigation Of Resistance To Barley Yellow Dwarf Virus And Detection Of Prevalent Population In Shaanxi

Barley yellow dwarf disease is caused by Barley yellow dwarf virus,in short BYDV.It was difficult for its control at present.It was first found in the wheat of Shaanxi and Gansu provinces,followed by a large-scale spread and result in a lost of more than 500 million kg in 1987.Now the disease is mainly distributed in the winter wheat region, spring wheat region and their hybrid zone of Northwest China,North China,Northeast China,Central China,Southwest China and East China, causing a serious cut.Selecting resistant varieties is the most economical and valid method for preventing and controlling BYDV, scholars at home and abroad had done many detailed research for the screening of BYDV-resistant wheat varieties since 70 to 80 years of the 20th century, but had not found any ideal BYDV-resistant materials. Therefore, make identification and investigation about resistance to BYDV among domestic existing varieties and germplasm resources becomes quite necessary.In 2007-2009, we investigated the natural rsistance to BYDV and the change of morbidity with the methord of strip cropping and artificial inoculation respectively about different varieties of wheat from Shaanxi. Simultaneously, in order to determinate the prevalent population of BYDV in the field of Yangling in Shaanxi province, A multiplex PCR system was stablished for simultaneous detection of BYDV population-GPV, GAV and PAV, eight samples from Yangling infected by BYDV were verified with the multiplex PCR system. We have following results:i. The incidence rate was different year by year.The morbidity of 2009 reached up to 86.5%, while it reduced to 10.6% and 14.0% in 2008 and 2009 respectively.ii. We did a second survey and found the morbidity increased largely while it changed little in some varieties been infected after artificial inoculation.iii. Several varieties such as Xiaobingmai and Yumai34 showed a recovery phenomenon, disease degrees of some of their diseased plants reduced from 5,6 to 2,0 at early and late stages respectively.iv. Qinfeng148, Xinong402, Shan715 and Xinong979 showed resistance to BYDV in successive 3 years while several varieties of Xiaoyan such as Xiaoyan6, Xiaoyan54, Xiaoyan597 showed high susceptibility, the morbidity of Xiaoyan after artificial inoculation account for 13.5% of all the 157 varieties.v. The phenomenon of mixed infection was heavy. The incidence of PAV was 25% in 8 diseased samples. Measured results indicated that our multiplex PCR system was stable and reliable for simultaneous detection of BYDV population.