Department of Plant Pathology, Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore-641003.
Abstracts of Research Papers Presented during the National Symposium of Indian Virological Society at Unit of Plant Virology, Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi-110 012, October 14–1.
Bhendi (Abelmoschus esculentus L., Family: Malvaceae), commonly known as lady's finger or okra is an extensively grown vegetable crop in India. The crop is afflicted by a number of diseases and among them viral diseases are very important. Recently, a new virus disease has been noticed in bhendi fields of TNAU. In field, the symptoms initiated on leaves as small chlorotic rings with yellow spots in the centre, which gradually increased in size and coalesced and caused leaf malformation. Orange discoloration of terminal young leaves was also noticed in case of systemic infection. The virus induced chlorotic rings, necrotic rings and veinal necrosis on inoculated cowpea plants. Out of the fifteen plant species tested, eleven showed susceptible reaction. The symptoms manifested varied from local lesions to systemic infection. The dilution end point of the virus was found to be between 10–3 and 10–4. The virus was inactivated at a temperature between 50°C and 60°C. The virus remained infective in buffered sap up to 24h at room temperature and up to 36h at 4°C. Electron microscopic observation of sap from infected leaves revealed isometric particles. On the basis of symptomatology, biological studies, physical properties and particle morphology the virus was identified as ilarvirus. This is the first record of natural occurrence of ilarvirus in bhendi in Tamil Nadu.
