The adults are small, yellow and brown, about 3 cm in body length, with conspicuous, broad, brown stripes running laterally through the eyes and extending posteriorly along the wings. The antennae are short, much less than the length of the body. When in swarms, they are in their migratory phase and are called locusts.
They are found in all rice environments but are prevalent in rainfed areas. They tend to localize in dry areas and rice fields adjacent to grasslands where they breed. They cannot be found along rice field margins during early hours of the morning and after sunset. Pampanga and several provinces in Mindanao are areas where they have caused havoc to cultivated crops, including rice.
Grasshoppers can damage rice at all stages of crop growth. Nymphs eat newly germinated rice seedlings and cause them to wither. Adults feed on the leaves and shoots, and may eat the base of the panicle causing it to wither and die.
If the emerging flowers are attacked, the resulting grains become chaffy. Swarming locusts can remove most of the foliage in a rice field leaving only the base of tillers.
Management options
Cultural
- Flooding the stubble drowns grasshoppers.
- Shaving of bunds kills egg pods.
- Sweeping along the bunds reduces their numbers.
- Adults are sluggish at night, can be picked directly from the foliage, and eaten by people.
Biological
- Small wasps attack grasshopper eggs.
- Parasitic flies, nematodes, and fungal and bacterial pathogens kill nymphs and adults.
- Birds (house sparrow), frogs, and web-spinning spiders are major predators of nymphs and adults.
