Bioscience Evidence 2026, Vol.16, No.4, 249-263 http://bioscipublisher.com/index.php/be 251 2.2 Habitat improvement Habitat improvement aims to maintain vegetation around rice fields, protect flowering plants, and reduce unnecessary disturbance. These practices provide food, shelter, and alternative prey for natural enemies. Agricultural fields are often disturbed by farming activities, making it difficult for predators and parasitoids to survive throughout the season. Improving ecological infrastructure can provide nectar, pollen, shelter, and alternative hosts, helping natural enemies remain active in both space and time. In rice production, ecological engineering usually includes preserving field-edge vegetation that supports overwintering parasitoids, planting flowering plants on field bunds, and reducing unnecessary insecticide applications during the early growing season to maintain the natural food web. Lower insecticide use, selective pesticides, and better habitat management are all important for conserving natural enemy populations. Field studies have shown that planting nectar-producing flowering plants along rice field bunds increases the abundance of natural enemies, improves parasitism rates, and strengthens pest suppression while maintaining stable rice yield with less pesticide use. Flowering species such as marigold, cowpea, and sesame are highly attractive to many beneficial insects. Rice fields with flowering plants supported larger populations of lady beetles, ground beetles, rove beetles, mirid bugs, damselflies, and spiders. These fields also produced higher rice yields and better economic returns than conventional fields (Meera et al., 2026). 2.3 Conservation of natural enemies Rice fields naturally contain a complex food web, where many predators and parasitoids help suppress herbivorous pests. Common natural enemies include spiders, predatory true bugs, parasitoid wasps, and many other beneficial insects that attack important rice pests. Surveys in early-season rice fields found that generalist predators such as spiders and mirid bugs were already abundant during the early crop stages. The application of organic materials and the maintenance of decomposer communities provide alternative prey for these predators, allowing their populations to establish before pest numbers increase (Hajjar et al., 2023). Spiders, dragonflies, damselflies, predatory mirid bugs, and egg parasitoids have repeatedly been identified as key natural enemies in eco-friendly rice production. Rice fields planted with flowering plants consistently supported higher numbers of spiders, damselflies, dragonflies, green mirid bugs, and parasitoid wasps. These fields also showed higher egg parasitism rates of brown planthoppers, striped stem borers, and rice leaffolders. In a biological control program carried out in the Greater Mekong Subregion, IPM based on Trichogramma parasitoids increased the abundance of natural enemies. Spider populations doubled, insecticide applications were reduced by 1.5 sprays per season, and rice yield increased by 2%~10% (Babendreier et al., 2020). Different groups of natural enemies attack pests at different life stages, feeding sites, and activity periods. Their complementary roles often provide stronger pest suppression, especially when rice fields offer diverse habitats that reduce competition among beneficial species (Snyder, 2019). 2.4 Integrated eco-friendly measures Light trapping is one of the most widely used physical control methods in rice production. Besides directly reducing pest populations, it also provides continuous monitoring information with little dependence on chemical pesticides. Solar-powered light traps can capture yellow stem borers, rice leaffolders, leafhoppers, planthoppers, rice bugs, and other important pests. Field studies showed that these traps significantly reduced pesticide applications and lowered pesticide costs by an average of 1 034 BDT per hectare (Rashid et al., 2022). Optimizing trap height and operating time further improves trapping efficiency and allows light traps to be integrated into IPM programs under different ecological conditions. Field experiments with Internet of Things (IoT)-based light-trap systems reported major reductions in both pest populations and pesticide use. In one study, pesticide use decreased by 91.67%, showing the strong potential of intelligent physical pest control technologies (Simpao et al., 2025). Sex pheromone traps are more selective and are especially useful for monitoring and controlling lepidopteran pests. In striped stem borer field trials, pheromone traps caught more moths throughout the season than light traps. Fields using pheromone traps had the lowest rates of white heads and dead hearts and produced the highest rice
RkJQdWJsaXNoZXIy MjQ4ODYzNA==