Repeat weather pattern of 2022 triggers paddy dwarfing virus outbreak in Punjab

This year’s outbreak of the Southern Rice Black-Streaked Dwarf Virus (SRBSDV), which causes severe dwarfing in paddy crops, appears to be closely linked to recurring climate patterns. A preliminary report of the study conducted by Punjab Agricultural University (PAU) has found that the weather conditions in 2025 — marked by similar rainfall, temperature, and daylight hours — mirror those of 2022, when the last major flare-up occurred.

The virus, transmitted by the white-backed planthopper (WBPH), leads to stunted growth, poor tillering, shallow roots, and narrow upright leaves. Infected plants often fail to mature, resulting in significant yield losses.

“We were introspecting why the disease hit in 2022 and again in 2025, skipping two years in between,” said Dr SS Gosal, Vice Chancellor, PAU. “One striking similarity was the weather pattern — overcast skies, hot and humid conditions, and identical rainfall and daylight hours. Our study confirms that these factors have contributed to the virus resurfacing.”

Dr Gosal added that climate plays a crucial role in crop health, influencing pest migration, disease outbreaks, and overall productivity. Even minor shifts in temperature or rainfall can alter the vulnerability of crops to infections. In the case of the SRBSDV, the virus thrives under specific climatic conditions, making weather a key trigger for its spread.

Surveys conducted by PAU across 20 districts in July and August confirmed the presence of SRBSDV in sub-mountainous areas, including Pathankot, Gurdaspur, Ropar, Fatehgarh Sahib, and Patiala. Field observations revealed that early transplantation played a major role in infection rates. Crops transplanted before June 20 were more vulnerable, while those transplanted after June 25 largely escaped infection.

“In the same village, we observed fields with and without the disease. The difference was transplanting dates,” Dr Gosal added. “We are compiling a detailed report to be submitted to the government.”

To contain the spread, PAU has issued insect-vector management guidelines. Farmers are advised to monitor WBPH populations and use only recommended insecticides such as Pexalon, Ulala, Osheen, Imagine, Orchestra, and Chess, in specified doses and water volumes.

Leading the on-ground response, Dr Gosal visited affected villages with senior scientists and urged farmers to stay alert and follow advisories issued by PAU’s Krishi Vigyan Kendras and Farm Advisory Service Centres.

As the study progresses, PAU emphasises timely action and informed practices to mitigate losses and guide future policy.