Rice seedlings are particularly vulnerable to a fungal disease known as blight, caused by *Rhizoctonia solani*, a soil-borne fungus that thrives in moist environments. This pathogen typically infects the roots and lower stems of young plants through wounds or natural openings such as lenticels. The disease is most prevalent under warm (around 20°C) and humid conditions, but it can also occur during hot and dry periods in July to September when overwatering leads to waterlogged soil. Infected seedlings often show symptoms starting from the root neck, with small, water-soaked lesions that appear light brown and irregular in shape. Over time, these spots expand, leading to rotting of the root cortex and stem base. Within a week, the affected parts may soften, causing the leaves to wilt and the seedlings to easily fall off, leaving only the woody xylem tissue. Similar symptoms can also appear on the leaves, resembling those of the stems.
To prevent and control this disease, several measures can be taken. First, select a well-drained, elevated site for the seedbed, and ensure the soil is loose and fertile. Disinfecting the soil before planting, using organic fertilizers, or treating it with *5406* (a bacterial preparation) can help reduce the risk of infection. During early stages of the disease, infected seedlings should be removed and burned immediately to prevent further spread. Applying a mixture of grass ash and lime (in a ratio of 8:2) around healthy seedlings can also help suppress the pathogen. In more advanced cases, fungicides such as 75% mancozeb at 800 times dilution or 75% chlorothalonil wettable powder at 600 times dilution can be applied.
For chemical control, several effective fungicides are available. These include pentachloronitrobenzene diluted between 200–400 times, or 50% carbendazim at 800–1000 times dilution, which should be sprayed once a week for 2–3 weeks. Alternatively, a Bordeaux mixture (1:1:200) or 0.3–0.5 degrees of lime sulfur can also be used to manage the disease effectively. Regular monitoring and timely intervention are key to minimizing losses and ensuring healthy seedling growth.
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