Non-systemic Infection of Tobacco streak virus on Cotton in Warangal District, Andhra Pradesh

摘要

During 2005, cotton was sown on 3.67 lakh acres in Warangal district of Andhra Pradesh, 62 per cent of it being Bt seeds. Hybrid RCH - 2 Bt alone was sown on 1.20 lakh acres. During late August 2005, several farmers complained about a disease causingchloroticecrotic lesions on leaves accompanied occasionally with leaf purpling, necrotic buds and drying up of young bolls in their cotton fields. It was also noticed that the incidence of the disease was more on Bt cultivars, compared to non Bt cultivars. A survey was conducted in some of the cotton fields to ascertain the extent of incidence and also to collect disease samples for the identification of causal agent. Samples collected during the survey were tested by Enzyme linked immuno-sorbent assay (ELISA) and studies carried out subsequently with cotton Tobacco streak virus (TSV) isolate gave interesting results, which we report hereunder.