The present study was conducted to investigate the etiology, mode of transmission and molecular relationship of the causal virus associated with Sunflower leaf curl disease with other related viruses. Leaf curl disease on sunflower caused by a begomovirus was observed to an extent of 40% for the first time on some hybrids grown in experimental plots at Main Research Station (MRS), Raichur, Karnataka, Southern India. Symptoms like curling, malformation of leaves, leaf thickening, leaf enations and severe stunting were observed on infected plants. The disease was successfully transmitted by whitefly, Bemisia tabaci. The experimentally inoculated plants produced symptoms similar to that of naturally infected plants. The causal virus was detected using two sets of begomovirus specific degenerate primers. The core Coat Protein (CP) gene fragment of 575 bases was amplified from naturally as well as whitefly inoculated plants. Phylogenetic analysis of the core CP gene sequence of the virus with those of other begomoviruses clustered next to Tomato Leaf Curl Karnataka Virus isolate Lucknow (ToLCKV-(Luc) (Accession No. EU604297.2) and Tomato Leaf Curl Virus-Bangalore II (ToLCBV-(Ban2) (Accession No. EU604297.2) and shared 97.5% nucleotide identities. Thus, its exact taxonomic status will require sequencing of the complete ssDNA viral genome. The begomovirus infecting sunflower, which we tentatively called Sunflower Leaf Curl Virus (SuLCV).
M.R. Govindappa, I. Shankergoud, K.S. Shankarappa, W.A.R.T. Wickramaarachchi, B. Anjeneya Reddy and K.T. Rangaswamy, 2011. Molecular Detection and Partial Characterization of Begomovirus Associated with Leaf Curl Disease of Sunflower (Helianthus annuus) in Southern India. Plant Pathology Journal, 10: 29-35.