Identification Of Resistance To Barley Yellow Dwarf Virus In Wheat Varieties And Infectious Cloning Inoculation Of BYDV-GAV

Wheat yellow dwarf disease is an important viral disease caused by barley yellow dwarf viruses(BYDVs),which often causes serious yield loss in winter wheat areas in northern China.BYDVs are spread by a variety of aphids for long-term specialization,and the virus returns to non-proliferation in the aphids.BYDV-GAV is the main pathogen of wheat yellow dwarf disease in China.Screening and identification of resistant varieties is an important method to control wheat yellow dwarf disease.Reverse genetics studies using infective cloning are important methods for analysing the gene function and pathogenesis of BYDV-GAV.In this study,field resistance test and film feeding technology were used to identify yellow dwarf resistance of various wheat varieties(lines),and virus propagation of BYDV-GAV invasive clones was explored.The main results are as follows: :1.Using pile measurement methods to identify the resistance of 96 wheat varieties to yellow dwarf disease,such as Yangmai 158,Shan 229,Shanyan 582,Xi Nong 211,Xi Nong 59,Fu Mai 2,Xi Nong 979 showed better resistance,which had low disease index and less affected by BYDV.The disease indexes of wheat varieties,such as Yiyang 106,Xiaoyan 16,Xi'an 118,Lingke 608,Dongfanghong 1,Xiong 151,Xichun 958 and Plain 50 were higher than 50,which showed high susceptible,while other varieties were middle susceptible.Field identification results indicated that BYDV-GAV infected wheat showing the symptoms of reduced plant height,ear length,thousand seed weight and chlorophyll content;decreased hormone leves of BR,JA and SA,increased hormone leves of ABA and IAA,and increased SOD,POD,CAT and MDA activities.2.Using the methods of film feeding,pCass-GAV-RZ vector was transferred from N.benthamiana to wheat by means of aphids.After RT-PCR verification,the virions had the ability of transcription and replication in wheat,and the further studies confirmed that infective clones could pass back to wheat with normal activity.These efforts provide data support and theoretical basis for screening,utilizing wheat yellow dwarf resistance resources,and analyzing the pathogenicity of BYDV-GAV.