Efficacy and adoption of neem-lime extract as seed and foliar treatments against African rice gall midge (<i>Orseolia oryzivora</i>) in rice production

The African rice gall midge (AfRGM), Orseolia oryzivora (Diptera: Cecidomyiidae), is a major constraint to rice production in sub-Saharan Africa, causing significant yield losses, particularly under rainfed and irrigated lowland conditions. Farmers often rely on synthetic insecticides, but their high cost, associated environmental concerns and limited effectiveness necessitate sustainable alternatives. This study, conducted from 2023 to 2024 in the rice-growing community of Edozhigi, Niger State, Nigeria, evaluated the efficacy and adoption of neem-lime extract as an eco-friendly management strategy against AfRGM. A 4 × 3 factorial field experiment tested four rice varieties (FARO 37, FARO 44, FARO 66, FARO 67) with two neem-lime extract treatments: seed soaking only and seed soaking plus foliar spray, with a control. In 2023, 80 farmers were trained using a learning-by-doing approach, and adoption was assessed in 2024 through structured questionnaires. Results showed that seed soaking plus foliar spray significantly reduced AfRGM infestation compared to seed soaking alone, particularly when integrated with FARO 67. Tiller infestation negatively correlated with grain yield (R² = 0.34–0.84). The extract enhanced yields (5.67 t ha−1 in 2023; 6.92 t ha−1 in 2024) without adverse effects on agronomic traits. Adoption was high (79.5%), influenced by farming experience (χ² = 17.00, p = 0.002), farm size (χ² = 6.85, p = 0.032) and education level (χ² = 24.23, p = 0.001), but not by age or gender. Most adopters (80.6%) prepared the extract themselves. Neem-lime extract, particularly integrating with FARO 67, offers a practical and environmentally friendly alternative to chemical insecticides for AfRGM management.