The symptoms associated with leaf scald vary according to plant age and growth stage , cultivar and plant density.
Newly developed lesions on the tips or edges of leaf lamina, are approximately 1-2 cm² in area with a grey-green, water-soaked appearance.
Lesions alternate between light-tan and dark-brown in color.
The affected areas dry out as they mature; this is accompanied by a transition from a zonate pattern to a scalded appearance.
Other symptoms include leaf tip blight (lesions without zonations), leaf blight (reddish-brown spots without necrosis), seedling blight (coleoptile decay with red-brown discoloration and root rot), leaf sheath browning (large areas of brown lesions without necrosis) and head blight (flower deformation and sterility with a light-brown discoloration of the glumes).
Management
Remove infected rice ratoons.
Follow proper weed control.
Avoid excess use of fertilizer.
Apply Nitrogen in split doses.
Incorporate rice stubbles into soil during tillage.
