RESUMO
Grapevine Pinot gris virus (GPGV) is a novel member of Trichovirus genus in Betaflexiviridae family. During 2018-2019, 114 leaf and green shoot samples were collected from the main vineyards in Iran Zanjan, Hamedan and East Azerbaijan provinces. After total RNA extraction and cDNA synthesis, the samples were tested by PCR assay using two pairs of specific primers corresponding to the coat protein (CP) and movement protein (MP) regions of GPGV, in which 6 out of 114 samples were found to be infected by GPGV. Population genetics analysis and molecular evolution of GPGV were done based on the CP and MP gene sequences of six new Iranian isolates and 53 additional isolates from several different countries in three continents: Asia, Europe, and America. The phylogenetic tree of GPGV isolates was clustered into two independent clades with significant F ST values (> 0.44). The ω values were calculated < 1 for the GPGV isolates for both genes. These findings demonstrated that the GPGV evolutionary selection pressure is under negative selection. To our knowledge, this is the first detailed study on the molecular characterization, phylogenetic analysis, and provide a better understanding of the population evolution of GPGV isolates from vineyards in Iran. The new Iranian isolates were lied in a new cluster near to European isolates. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02914-5.
RESUMO
Tomato spotted wilt virus (TSWV; Genus Orthotospovirus: Family Tospoviridae) is one of the most destructive viruses affecting a wide range of horticultural crops on a worldwide basis. In 2015 and 2016, 171 leaf and fruit samples from tomato (Solanum lycopersicum) plants with viral symptoms were collected from the fields in various regions of Iran. ELISA test revealed that the samples were infected by TSWV. The results of RT-PCR showed that the expected DNA fragments of about 819 bp in length were amplified using a pair of universal primer corresponding to the RNA polymerase gene and DNA fragments of ca 777 bp and 724 bp in length were amplified using specific primers that have been designed based on the nucleocapsid (N) and non-structural (NSs) genes, respectively. The amplified fragments were cloned into pTG19-T and sequenced. Sequence comparisons with those available in the GenBank showed that the sequences belong to TSWV. The high nucleotide identity and similarities of new sequences based on the L, N, and NSs genes showed that minor evolutionary differences exist amongst the isolates. The phylogenetic tree grouped all isolates six clades based on N and NSs genes. Phylogenetic analysis showed that the Iranian isolates were composed a new distinct clade based on a part of polymerase, N and NSs genes. To our knowledge, this is the first detailed study on molecular characterization and genetic diversity of TSWV isolates from tomato in Iran that could be known as new clade of TSWV isolates.
