Molecular Diagnostics and Characterization of Begomovirus Causing Leaf Curl Disease in Potato (Solanum Tuberosum)

Abstract

Potato (Solanum tuberosum) is a starchy, tuberous crop belonging to family Solenaceae and genus Solanum. It is an important crop for ensuring food and nutritional security to the developing world. Potato is vulnerable to many viral diseases which causes decline in yield and quality. Potato apical leaf curl disease occurs due to whitefly transmitted begomovirus. The present study was focused on the molecular diagnostics and characterization of begomovirus causing leaf curl disease in potato. 36 samples were collected from villages of Meerut distinct showing typical symptoms of leaf curling; yellow mottling, stunting, yellowing or mosaic leaves, crinkling. Molecular diagnostic of Tomato leaf curl virus was performed using polymerase chain reaction. Total DNA was extracted from infected Potato leaves using coat protein gene specific primers. Out of 36 samples, only 18 samples were found to be positive in PCR with amplification of ~770 bp. RCA based diagnostics ofTOLCV was developed. The amplified product of coat protein gene was eluted and cloned in pTZ57Rff and confirmation using colony PCR and restriction digestion approaches. The cloned product of coat protein gene ~750 and DNA-B RCA product of ~2700 bp was also cloned in pTZ19R and sequenced. Further, the sequences obtained were subjected to Jn-silico analysis through BLAST analysis and phylogenetic tree construction using MEGA5.0 software which revealed close similarity of sequences with coat protein gene and DNA-B components of other potato begomoviruses which are all tentative strains of ToLCNDV. Based on these findings the virus infecting potato has been identified as an isolate ofToLCNDV with bipartite genome.