One of the most destructive insect pests of rice is the rice weevil, which eats the grains both in the field and in storage. The rice stem borer, a caterpillar, destroys rice fields. Stunt, a virus disease that dwarfs rice plants and reduces their production, has caused famines in eastern Asia.

Hoja blanca (Spanish for "white leaf") is a virus disease introduced into the United States from Latin America in 1958 and 1959. This disease turns the leaves white, injures the spikelets, and cuts the yield 80 per cent or more.