Sheath Blight (Hawar pelepah)

Sheath blight is a significant disease in rice plants. This disease destroys the midrib, so it is necessary to open the planting canopy to find and recognize the condition. The disease causes plants to fall quickly. The earlier it falls, the greater the loss it causes. This disease causes the grain to be less filled or even empty. Sheath blight usually occurs when the plant begins to form tillers until just before harvest. However, this disease can also occur in young plants.

The disease is caused by the fungus Rhizoctonia solani, with early symptoms of pale white oval or round spots on the midrib. Under favorable (moist) conditions, the disease can reach the flag leaf. Pathogens survive and spread with the help of a resistant structure called the sclerotium.

This disease is challenging to control because the pathogen is polyphagous (has a vast host range). Plant fertilization with a dose of 250 kg urea, 100 kg SP36, and 100 kg KCl per ha can suppress the development of this disease. How to prevent the disease:

• Arrange the planting in the field so that it is not too close;
• Dry the fields for a few days at the time of maximum tillering; 45
• Deep plow to bury infected plant debris;
• Crop rotation with nuts to lower attack disease;
• Remove weeds and diseased plants from the fields;
• Use fungicides (if needed), including those with active ingredients: hexaconazole, carbendazole, canecanazole, sulfur, flutalonil, diphenoconazole, propiconazole, or validamycin A

Source: Putra, R. (2018). Hama dan penyakit tanaman padi dan deskripsi padi sawah. Balai Pengkajian Teknologi Pertanian Kepulauan Riau.