According to university spokesman whitefly was sucking pests attacking cotton and many other crops. It damaged crop by sucking the sap from leaves and by vectoring deadly diseases like cotton leaf curl virus. Its feeding resulted in the development of black fungus, a sooty mould on its excreta, which inhibit photosynthesis, he said adding that when unchecked, whitefly ultimately caused burning or drying up of plants.

The scientists have advised farmers to stop using synthetic phrethroids and their mixtures and instead suggested spray of triazophos and ethion on cotton for control of the deadly disease, the spokesman said. Whitefly was confined to lower surfaces of leaves at allstages, fine spraying for through coverage were important for control of the menace. The damage due to pest attack in Punjab may cause severe loss to the current standing crop leading to a dent in the national cotton production.

While international trade in cotton is likely to remain subdued in the year 1999-2000 due to world-wide recession, the cotton crop prospects in the country is likely to witness a better crop during the same year, but may have certain negative implications due to pest attack. The reports emanating from the three cotton growing zones indicate that the production may exceed the crop size of 1998-99. However the area under cotton cultivation in 1999-2000 may be lesser as compared to 93 lakh hectares during 1998-99.

Two years back similar pest attack in the northern belt had caused a severe problem. In a bid to increase cotton production in the northern belts, hit by the leaf curl virus menace, the Indian Council for Agriculture Research (ICAR) had drawn up an action plan for effectivemanagement of the disease. ICAR had asked concerned states and various agencies and seed corporations to initiate effective measures, to contain the menace in the affected areas.

State seed corporations were told to produce more desi varieties such as RG-8 and LD-427 which were more pest resistant. The agriculture departments should ensure the cultivation of desi varieties in the endemic areas and along the international border, the action plan had suggested.

The state agriculture departments were asked to ensure seed treatment with imidochloprid at the time of sowing, which have shown encouraging results to contain the disease. This technology should be popularised among the farmers through electronic and print media, it suggested.

The departments should take care in using insecticides regularly and alternately at 10-12 days interval in the areas affected by white flies in a mild form. Immediate steps such as burning of affected plants should be taken to avoid further spread of the virus, the plansuggested.