Tomato, pepper, eggplant, okra, tobacco, beans, cotton, cucurbits, citrus, okra, sunkukra, gurhal/ chinese rose, til, potato, brinjal, pumpkin, musk melon, water melon, Luffa, Momordica, sunflower, datura, gul-e-khera, Convolvulus(lehli), Calotropis (ak), Amarantus (karund), jute, Geranium(rattan jote), Euphorbia(hazar dani), Phylanthus(amla),Ipomea, Capsicum(red pepper) etc and other crops as secondary hosts.
Favorable factors for development of disease
Ø Presence of whiteflies
Ø Infected plants
Ø Weedy fields
Ø Viruliferous whitefly
Ø Favorable environment.(Temperature, Humidity, Sun Shine, Rain etc)
Symptoms:
The observable signs of virus infections on plants and provide first clue in the field. virus infect the wide range of cultivated plants causing a variety of symptoms .Symptom expression depends on virus and its strain , host genotype ,stage of infection of the host ,nutrition or growth conditions and environmental factors. Mainly the temperature and light .A virus after entry in the host begins to replicate in the cells and alters its metabolism resulting in biological , physiological and morphological changes primary symptoms develop at the site of virus entry in mechanically inoculated leaves ; called as local lesions . Secondary or systemic infection occurs when the virus is not confined to the site of inoculation but it spreads to other cells with in leaf mesophyll, usually through plasmodesmate connection and reaches vascular system, phloem in most of the cases. there fore ,severe symptoms may develop when a virus has infected a plant systemically. The nature and severity of diseases. symptoms will determine the economic importance of a particular virus in term of yield reduction and reduced quality symptoms ma be internal or external
The first symptoms of infection in cotton appear within 2-3 weeks of inoculation. Initially characterized by deep downward cupping of the youngest leaves. Upward or downward .curling of the leaf margins. Formation of enations on the veins frequently develop into cup-shaped, leaf-like structures.
Infected plant has stunted young leaves and shoots. It grows very slowly, becomes bushy, and dwarfed. The leaf margin rolls either inward or upward and is rather stiff with yellowish margin. Its leaves are thicker than normal, with leathery texture. The young leaves have yellowish color, cupped, thick, and rubbery.
Vector Relationship of CLCuv
- Virus is transmitted by vector and by grafting.
- Not transmitted by seeds; not transmitted by pollen or any other means.
Whitefly Bemisia tabaci(Genn).
- Order Homoptera
- Family Aleyrodidae
- Genera 126
- Species 115
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