Timely Detection, Integrated Management Key To Controlling Bacterial Blight In Paddy

Indian Council of Agricultural Research–National Institute of Biotic Stress Management (ICAR-NIBSM) advises farmers on early identification and scientific management of the disease

Bacterial leaf blight is an important bacterial disease that can affect paddy crops in Chhattisgarh and other major rice-growing regions of the country. The Indian Council of Agricultural Research–National Institute of Biotic Stress Management (ICAR-NIBSM) has advised farmers to regularly monitor their fields for early detection of the disease and adopt integrated disease management practices. The disease is primarily caused by the bacterium Xanthomonas oryzae pv. oryzae.

Bacterial leaf blight generally begins at the edges or tips of paddy leaves. Infected leaves develop water-soaked, pale yellow or yellowish-green spots and streaks. As the infection progresses, the symptoms spread across larger portions of the leaves, which gradually turn yellow and acquire a straw-coloured appearance before drying. Severe infection during the early growth stage may lead to a condition known as ‘kresek’, in which affected plants begin to wilt.

Timely identification of the disease is important as its early symptoms may resemble those of other leaf diseases. Farmers have been advised to seek confirmation from agricultural scientists, experts, Krishi Vigyan Kendras or the Agriculture Department when suspected symptoms are observed in the field.

According to ICAR-NIBSM, temperatures ranging from 25 to 34 degrees Celsius and relative humidity above 70 per cent are generally favourable for the development of bacterial blight. Continuous rainfall, strong winds, high moisture levels and excessive water in fields can facilitate the development and spread of the disease. Excessive application of nitrogen fertilisers, particularly heavy late top-dressing, may also increase disease severity.

For effective disease management, farmers have been advised to give priority to resistant or tolerant varieties, balanced nutrient application, proper water management, field sanitation and integrated disease management practices. Copper-based products, such as copper oxychloride, may be used wherever necessary and as per prevailing government recommendations. The appropriate dosage and method of application should be determined strictly on the advice of the local Agriculture Department or agricultural experts.

The institute has cautioned farmers against unnecessary, repeated or excessive application of antibiotics, as such practices can contribute to the development of antimicrobial resistance. The use of antibiotics or other chemical products should be undertaken only in accordance with current government recommendations and the advice of agricultural experts.

Farmers have been particularly advised to maintain regular surveillance of paddy fields during periods of rainfall and high humidity. The appearance of yellowing from leaf margins, water-soaked spots or streaks, straw-coloured leaves and wilting plants should be treated as warning signs requiring immediate attention. Timely detection, balanced crop management and treatment based on scientific advice can help minimise the impact of bacterial blight on paddy production.