Promoting biodiversity for climate-resilient pest management in rice

Rice, a staple food in Southeast Asia, is a major source of greenhouse gas emissions. Climate change exacerbates insect pest risks in rice production. Innovative, sustainable solutions are critical for enhancing rice sector resilience. Biodiversity management in rice-based ecosystems is promising but faces adoption challenges. This study aims to assess farmer’s preferred biodiversity management strategies for ecosystem services and profitability. Initial consultations with farmers identified mung bean as the preferred bund crop and watermelon as the preferred dry season crop after wet season rice. During the field study from 2022 to 2024, we compared four treatments: 1) rice grown without pesticides and with no bund crop in the wet season and no crop in the dry season, 2) rice grown without pesticides, but with mung bean as a bund crop in the wet season and watermelon in the dry season, 3) rice grown with pesticides but without a bund crop in both seasons, and 4) rice grown with pesticides but without a bund crop in the wet season and watermelon in the dry season. We assessed arthropod diversity, insect pest damage, agronomic metrics, cost-benefit and greenhouse gas emissions. Results indicate less thrips damage in pesticide-free treatments, consistent grain yields across treatments, and a higher benefit-cost ratio for the rice-watermelon system. The relative abundance of arthropods is affected by treatment and development stage of crop and the GHG emissions are lower in the diversification system. Further analysis will provide insights into the effectiveness of biodiversity management for climate resilience.