Paddy or rice is a staple food in many parts of the world. Unfortunately, rice crops are vulnerable to many pests and diseases, causing significant yield losses. One of the most damaging pests in rice cultivation is the stem borer, which can cause up to 50% yield loss in affected fields. In this article, we’ll discuss the control of stem borer attack in paddy.
The stem borer is a moth whose larvae bore into the rice stem, causing physical damage and creating entry points for diseases. The larvae damage the plant’s vascular tissues, causing the plants to wilt, reducing yield, and often resulting in plant death. The adult moths lay eggs on the paddy leaves’ undersides, which then hatch into larvae and bore into the stem. The incidence of stem borer attack increases during the rainy season, as moisture and high humidity favor the insect’s development.
There are various strategies to control stem borer attack in paddy. These include:
1. Cultural practices: Farmers can practice crop rotation and avoid planting rice in the same field in consecutive years. This reduces the stem borer population and break the pest’s life cycle. Farmers can also plant resistant paddy varieties to minimize damage. Removing crop residues and plowing rice fields after harvest also reduces the chances of stem borer infestation.
2. Mechanical control: Trapping adult moths using light traps can reduce the stem borer population in paddy fields. Stem borer-infested plants can be removed and destroyed manually, or an infected patch of field can be burned to eliminate the insect’s habitat.
3. Biological control: The use of natural enemies of stem borers can be an effective way to control their population. Hymenopteran parasitoids, such as the egg parasitoid Telenomus and the larval parasitoid Cotesia, can be introduced into paddy fields to control stem borer populations. These beneficial insects lay eggs on or inside stem borer larvae, eventually killing them.
4. Chemical control: Insecticides can be applied to paddy fields to control stem borers. However, chemical control should be the last resort as it is hazardous to human health and the environment. Overuse of insecticides can also result in the development of resistance in stem borers, making control efforts ineffective. If using insecticides, farmers should use a licensed professional and follow the application guidelines strictly.
In conclusion, stem borers pose a significant threat to paddy cultivation. Farmers can use cultural, mechanical, biological, and chemical control measures to minimize damage and keep stem borer populations under control. Integrated pest management techniques combining several control methods can be implemented to reduce stem borer numbers and protect the rice crops.