Eco-friendly management of root-knot nematodes (Meloidogyne spp.): biological and botanical control strategies

Abstract

Root-knot nematodes (RKNs, Meloidogyne spp.) are major agricultural pests, infecting over 5,000 plant species and causing significant economic damage by forming galls and interfering with nutrient flow. Due to the environmental and health risks associated with chemical nematicides, there is an increasing demand for environmentally sound management measures. This review explores sustainable alternatives, focusing on biological and botanical control strategies. Biological control utilizes natural antagonists such as bacteria (Bacillus, Pseudomonas, Pasteuria penetrans) and fungi (Trichoderma, Purpureocillium lilacinum), which suppress nematodes through mechanisms like direct killing, parasitism, and inducing plant resistance. These agents not only regulate RKN populations but also promote plant growth and systemic resistance, supporting a safer agro-ecosystem. Botanical control involves using plant-derived nematicides like neem seed cake and extracts from plants such as Melia azedarach and Brassica macrocarpa. Key bioactive metabolites, including alkaloids, terpenoids, and phenolics, contribute to nematode control by exhibiting direct nematicidal activity and bolstering plant defense reactions. Essential oils and allelopathic cover crops are also highlighted as eco-friendly tactics. The integration of biological and botanical methods, often combined with organic amendments and crop rotation, offers a holistic and multi-faceted approach to nematode management, aiming for increased efficacy, reduced chemical reliance, and prolonged agricultural sustainability. Despite the potential, constraints like variability in field efficacy, economic barriers, and the complexity of developing resistant cultivars limit widespread adoption. Future directions include the application of omics technologies and nanotechnology to support sustainable management.