Rice Stink Bug, Oebalus pugnax (F.)

Pair of adult rice stink bugs mating on a rice panicle. Photo by J. Saichuk, LSU AgCenter.

Damage caused to rice leaf by rice stink bug feeding. Photo by J. Saichuk, LSU AgCenter.

Rice stink bug egg mass on the leaf of a rice plant. Black, barrel-shaped eggs are laid in parallel rows. As the eggs mature, the color turns to red. These eggs have already hatched. Photo by J. Saichuk, LSU AgCenter.

Overview:

Adult rice stink bugs are shield-shaped, metallic-brown insects (½-inch long). Adults overwinter in grass clumps and ground cover until they are attracted to rice during the bloom stage. Females lay eggs on the leaves, stems and panicles of rice plants. In less than 2 weeks, immature stink bugs (nymphs) emerge from eggs. Nymphs develop through five instars in about one month. With each successive molt, nymphs increase in size, and the color of later instars becomes tan-green. Adults live about one month.

Facts:

• Nymphs and adults feed on rice florets and suck sap from developing rice grains.
• Feeding during the flowering and milk stages causes empty grains and reduces yield.
• Feeding during the soft-dough stage introduces pathogens into the grain causing discolored and pecky rice grains.

What you should look for:

• Scout using a 15-inch sweep net for adult RSB.

How you can manage rice stink bugs:

• Insecticidal control based on the results of field scouting is recommended when rice stink bugs exceed the treatment threshold. Please consult your local extension service for the current threshold.