1Indian Agricultural Research Institute, Regional Station, Kalimpong-734301.
2Bidhan Chandra Krishi Viswavidyalaya, Mohonpur-741252.
3Unit of Plant Virology, Indian Agricultural Research Institute, New Delhi-110012.
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.
Chilli (Capsicum annuum) is one of the important spice crop in Kalimpong hill region of West Bengal. In recent years it was noticed that yield of this crop is reduced remarkably due to infection by viruses causing the so called yellow mosaic disease syndrome. Survey was conducted to record the distribution, incidence and severity of this disease in different location with varying altitude.
Per cent infection of the disease was recorded up to 5–100% with 5–75% severity (PDI) depending upon the altitude. In highe raltitude maximum disease incidence was found to be 12% and disease severity upto 15% as against…… to…….% at lower altitudes. The virus infected plants showed systemic mosaic mottling, deformatio of leaves, reduced leaf and plant sizes and in severe cases shoe string symptoms.
The virus was mechanically transmitted to the following different host plants, Chili cv. Kalimpong local, chilli cv Pusa Jawala, Nicotiana glutinosa, Nicotiana rustica, Nicotiana debaryanum, Nicotiana tabacum var and xanthi and White burley. In electron microscope leaf-dip preparation from different infected leaf samples revealed the presence of two types of virus particles, spherical similar to cucumo virus (CMV) and flexuous filamentous virus like potyvirus (PVY). It was also found that single infection by CMV of PVY was also there in some plants while some plants showed mixed infection. These infections were confirmed byISEM and DAC-ELISA.
March planting of the crop in field showed reduced disease severity and increased fruit yield. Plants grown under shade shwoed more disease incidence and severity as compared to direct sunlight. Effect of fertilizer application and spraying of systemic insecticide on the measurement of the disease will be disucssed.
