Molecular Virology Laboratory, National Botanical Research Institute, Lucknow, India.
Abstracts of the papers presented at the XVIII National Conference of Indian Virological Society at Post Graduate Institute of Medical Education and Research, Chandigarh, India, December 11–13, 2008.
Cotton crop is severely affected by cotton leaf curl disease (CLCuD). Cotton leaf curl virus (CLCuV, genus Begomovirus), satellite DNA β and DNA1 (genus Nanovirus) components are associated with CLCuD. DNA β is responsible for symptom development with plants failing to produce cotton bolls in extreme cases. As a first step to down regulate DNA β, attempts were made to express βC1 in Nicotiana tabaccum. Naturally infected plants of cotton showing CLCuD symptoms were collected from Bhatinda district of Punjab. Total DNA was isolated from the leaves of diseased plants, and was subjected to PCR using primer pair specific for CLCuV DNA β. The PCR amplicon (1.3 kb) was cloned and sequenced, and oligo primers specific for βC1 gene (sense and antisense orientations) were designed. The gene constructs carrying βC1 gene (sense/antisense) under CaMV 35S promoter were designed and introduced into Agrobacterium tumifaciens. Nicotiana tabacum was transformed using leaf disc method. The transformed N. tabaccum plants having complementary sense βC1 showed CLCuD symptoms, while those having antisense βC1 showed normal phenotype. The detailed phenotypic evaluation and molecular characterization of the resistant tobacco lines are in progress.
