Association of Begomovirus with Okra (Abelmoschus esculentus L.) leaf curl virus disease in southern India

A severe leaf curl disease of Okra with high disease incidence and loss of production was observed during field survey of various locations of Southern India, and causal organism was identified as Begomovirus and its association was confirmed by polymerase chain reaction (PCR) but also by cloning and sequencing of amplified PCR products and whitefly transmission. The DNA β and Coat protein gene was cloned and sequenced. The sequence data were assembled and analyzed by using the Bio-Edit (version 5.0.9). The nucleotide sequences of DNA β and Coat protein gene showed highest identities with Bhendi yellow vein mosaic virus isolates. But the most important and novel observation was recorded that the infected plants with severe leaf curl disease never develops yellow vein mosaic symptoms during same field conditions. These findings suggest that the association of Begomovirus with severe leaf curl disease could be strain of Bhendi yellow vein mosaic virus occurring in southern India. The above findings require more study to confirm strong association of causal organism with this unique symptom.