Phylogenetic Analysis of Okra Enation Leaf Curl Virus (OELCV) Transmitted by Bemisia tabaci Using Coat Protein Gene Fragment of OELCV in Tamil Nadu

Okra enation leaf curl virus (OELCV) is a severe emerging disease of okra, Abelmoschus esculentus in India, causes systemic infections and has a very effective mode of transmission by the sweet potato whitefly, Bemisia tabaci; thus, preventing their spread has been made very complicated. It is essential to understand the OELCV isolates to study the disease reactions in plant accessions. The okra OELCV infected young leaves were collected from the Salem (Northwestern Zone) and Madurai (South Zone) of Tamil Nadu and the DNA was extracted and used to amplify the OELCV utilizing specific primers (JKOE34F, JKOE35R) targeting the OELCV coat protein gene and produced a 796 bp band in the polymerase chain reaction (PCR). The homology analysis of nucleotide sequence was carried out using BLAST programme and the results revealed that the Salem region coat protein gene sequence grouped into OELCV clone 6.2, complete genome (MK084768.1) with 99.71% of homology, and Madurai region coat protein gene sequence grouped into OELCV isolate Vijayawada coat protein (AV1) gene complete cds (KT935487.1) with a 99.38% of homology. The amplified OELCV (Salem and Madurai zone) from the study had aligned in the same cluster along with HG938362.1 and KX710156.1. This study had indicated that the OELCV pathogen alike in these zones successfully being transmitted by B. tabaci.