A looming belowground threat: assessment of climate-driven global expansion risk of Meloidogyne spp. in tobacco-growing regions

The global distribution of tobacco (Nicotiana tabacum), a crop of major economic importance, and its soil-borne pest root-knot nematodes (Meloidogyne spp.), which cause substantial yield losses worldwide, is strongly influenced by climatic and soil edaphic factors. Identifying regions of spatial overlap between tobacco suitability and nematode occurrence is essential for assessing vulnerability to pest-induced yield losses under changing environmental conditions. In this study, species distribution modelling was applied to quantify current and projected global suitability for Nicotiana tabacum and Meloidogyne spp. using the Maximum Entropy (MaxEnt) modelling across baseline (1970–2000), mid-century (2021–2040), and late-century (2081–2100) periods under three Shared Socioeconomic Pathways (SSP126, SSP245, and SSP585). Models were developed using global occurrence records and predictor sets comprising 19 bioclimatic variables, elevation, and soil edaphic properties, including soil texture, soil organic carbon, and soil pH, evaluated both jointly and independently to disentangle their relative contributions. Model performance was high for Meloidogyne spp. (training AUC up to 0.93) and moderate for N. tabacum (AUC ≈ 0.78), indicating reliable discrimination of suitable habitats. Baseline projections revealed extensive suitability overlap in major tobacco-producing regions such as South and Southeast Asia, sub-Saharan Africa, and parts of South America. Soil edaphic factors emerged as primary determinants of nematode suitability, whereas tobacco distribution was more strongly constrained by temperature and precipitation seasonality. Future projections indicated progressive contraction and fragmentation of tobacco-suitable areas, accompanied by pronounced spatial restructuring of nematode suitability and an expansion of high-risk overlap zones under intermediate and high-emission scenarios. These results demonstrate that climate change may intensify crop–pest interactions in specific regions, emphasizing the importance of integrating climatic and soil constraints into long-term agricultural risk assessment and management strategies.