Abstract:

This study is designed to conduct molecular identification of tomato yellow leaf curl virus (TYLCV) arised in Hebei Province, and analyze their variation and phylogenetic relations. In the study, a pair of specific primers PA1-F/R was designed according to known genome sequence of TYLCV to conduct PCR detection, and then the generated specific segments were collected, cloned and sequenced. Next, a new pair of primers PA2-F/R was redesigned according to the sequence to amplify the near whole sequence of virus sample, and conducting homology comparison and molecular evolution analyzing. The result indicated that all specific segments attained from the 4 virus samples by PA1-F/R primers were approximate 645bp. Also, by sequencing and analyzing on DNA-A, it discovered that total length of the 4 virus samples were 2781-2782 nucleotides, coding 6 ORFs in all. Through comparison of genomes, it found that the 4 sample DNA-A had the highest probability in homology with TYLCV reported in Shandong, Shanghai, Zhejiang, Anhui, Japan and Australia at above 99.0%, and belonged to the same large branch with TYLCV reported in America, Afric and Europe. This study demonstrated that the 4 samples were infected with TYLCV, and it is highly probable that they were isolates of TYLCV-Israel strain.