Identification Of Grapevine Viruses In Inner Mongolia Autonomous Region And Full-genome Sequence Analysis Of Grapevine Pinot Gris Virus Inner Mongolia Isolate

Grape(Vitis vinifera)is one of the world's oldest cultivated fruit trees,with apples,oranges and bananas,and listed as the world's four big fruit,but it is also one of the most vulnerable to viruses infect fruit trees,the virus will seriously affect the grape yield and quality,in recent years,Inner Mongolia autonomous region facilities and outdoor grapes grape acreage showed a trend of increasing,In order to understand the classification of grapevine virus species and isolates in the region,this study used conventional RT-PCR combined with gene sequencing technology to detect 14 grapevine viruses in 69 grape samples collected from 7 urban areas of Inner Mongolia Autonomous Region,and the results showed that a total of 9 grapevine viruses were detected.The detection rates were 8.7%(6/69)for GFab V,68.1%(47/69)for GFk V,7.2%(5/69)for GINV,2.9%(2/69)for GLRa V-2,39.1%(27/69)for GLRa V-3 and 23.2%(23.2%)for GPGV(16/69),GRSPa V was 63.8%(44/69),GVB was 2.9%(2/69)and GVE was 5.8%(4/69).All of these viruses could infect the plant with other viruses.Sequence analysis showed that the evolutionary tree could be divided into the following two rules.The first one was that the effective sequences of GFab V,GLRa V-2,GVB and GVE isolates were all in the same evolutionary branch and belonged to the same group.The second one was that the effective sequences of GFk V,GINV,GLRa V-3,GPGV and GRSPa V isolates were located in two or more evolutionary branches and belonged to multiple groups.Meanwhile,the second grape virus had different effective sequences of the same isolate distributed in different evolutionary branches.The effective sequences of 9 isolates from Inner Mongolia showed no specificity of geographic origin.The nucleotide consistency analysis showed that the nucleotide consistency range of the effective sequences of the Inner Mongolia isolates was significantly different from that of the corresponding reference sequences,with either 100.0% identical or 69.1% at the lowest level.Grapevine Pinot Gris Virus(GPGV)was first discovered in Italy in 2012.Michel et al.believed that China might be the origin country of GPGV through phylogenetic and genetic diversity analysis.However,only one GPGV genome has been reported in China.In this study,to enrich the genome-wide population information of GPGV in Chinese grapes,the whole genome of GPGV isolated from Inner Mongolia was cloned from the above GPGV positive grape samples.Two GPGV Inner Mongolia isolates were named GPGV1 Inner Mongolia and GPGV3 Inner Mongolia,respectively,and their genomic structures were similar to those of other known isolates.Sequence analysis showed that no recombinant event occurred in the whole genome of the two GPGV Inner Mongolia isolates.The nucleotide consistency was low with other known GPGV isolates.From the perspective of the evolutionary tree constructed by the whole genome,Rd Rp and MP,the two GPGV isolates from Inner Mongolia belonged to the same independent subgroup as the previously reported GPGV isolates from China and had a special isolation status.From the perspective of the evolutionary tree constructed by CP,GPGV3 Inner Mongolia belongs to the same subgroup as GPGV isolates previously reported in China and most of the other GPGV isolates,while GPGV1 Inner Mongolia forms an evolutionary branch independently.