Associations of soil type and previous crop with plant-feeding nematode communities in plantain agrosystems

Understanding the influence of soil properties and cultural practices on the communities of plant-feeding nematodes (PFNs) in agrosystems is a prerequisite for cost-efficient and environment-friendly pest control. Although plantain is a staple food crop in the Caribbean, the relationships between PFN communities and environmental factors are poorly understood in plantain agrosystems. In this study, which was conducted in Martinique (French West Indies), we quantified the PFNs in 301 root samples taken from 53 plantain fields that differed in climate, edaphic conditions, and cultural practices. The physico-chemical properties were also determined for the soil in each field. Coinertia analysis (CI) and General Linear Mixed Models (GLMMS) were used to investigate the relationships between the PFN communities, soil properties, and cultural practices. Four nematode taxa were found in plantain roots: Radopholus similis, Pratylenchus coffeae, Helicotylenchus multicinctus, and Meloidogyne spp. The lesion nematode P. coffeae was the most prominent PFN species, followed by the burrowing nematode R. similis, root-knot nematodes Meloidogyne spp., and the spiral nematode H. multicinctus. P. coffeae was significantly more abundant in ferralsols and nitisols (which have a low organic matter content and a high exchangeable cation content) than in andosols (which have a high organic matter content). Nematode abundances were apparently affected by the previous crops e.g., P. coffeae was slightly more abundant in fields where tuber plants such as sweet potato, yam, or dasheen were the previous crop; R. similis was particularly abundant in fields where banana or plantain was the previous crop; and Meloidogyne spp. were abundant in fields where a market garden was the previous crop. The results of this study will be useful for the design of PFN control methods in plantain. (Résumé d'auteur)