The Evolution Dynamic Of Potato Virus Y Group In China

Potato virus Y(PVY)is one of the most harmful potato viruses in China.It not only harms the potato industry in China,but also has a huge impact on China's tobacco industry.As an RNA virus,its variability is strong and many strains have evolved so far.Different strains of PVY have different resistances.Therefore,The potato industry urgently needs a method that can effectively identify the potato virus Y strain and the evolutionary trend of the PVY strain population for targeted management.This study first selected potato from Zhengzhou market for total RNA extraction from plants and performed RT-PCR to amplify PVY RNA sequences.After sequencing,strains were identified by establishing a phylogenetic tree.Secondly,this experiment selected multiple strain identification methods to compare and verify each other to determine the most simple and accurate strain identification method.Finally,this experiment through the in-depth excavation of a large number of Chinese PVY virus sequences in the database and strain identification of these sequences,fully simplifies the experimental process,shorten the experimental time,preliminary explored the evolution of PVY strains in various regions of China,analysis of PVY strains Department of evolutionary trends.Firstly,the phylogenetic tree was established by NJ method to identify the PVY-ZZ isolates as PVYN strains.Secondly,the methods of DNA sequencing,multiplex RT-PCR,amino acid mutation site verification,Blast database comparison and difference establishment of phylogenetic tree were used.After the comparison and verification,a strain identification technique based on the phylogenetic tree was established.This technique does not rely on complicated detection equipment,and the experimental operation is convenient and simple,and the experimental results are accurate and reliable.This technique mainly utilizes a large number of PVY gene sequences already published in GenBank.Through sequence analysis,the occurrence of PVY strains in each region and the evolution of strains are ascertained.The phylogenetic tree established by NJ method is the best method for strain identification.The establishment of a phylogenetic tree based on the MP method to verify the results of the establishment of trees can minimize the strain identification time and reduce the operationdifficulty.In rare cases,there will be a picture that cannot clearly distinguish between strains.At this point,the serotype amino acid variation site analysis and the BLAST database alignment result can be used to analyze the graphs to determine the final strain.Finally,this experiment found that the dominant PVY strains in the country are N:O strains,the secondary dominant strains are O strains and N strains,and the C strains,NTN strains,and NW strains are in a weak position in China..With the change of time,N:O strains have good evolutionary conditions and strong transmission in the four major planting areas in China compared to other strains,and gradually evolved into mainstream strains.