Opposite Fates Under Warming: Climatic Suitability, Niche Divergence and Phenological Exposure of Riptortus pedestris and Nezara viridula in Soybean

The bean bug, Riptortus pedestris (Fabricius), and the southern green stink bug, Nezara viridula (L.), are important pod-sucking pests of soybean, Glycine max (L.) Merr. Their feeding on pods and developing seeds induces soybean staygreen symptoms and causes severe yield losses. To assess their future damage risk, we integrated MaxEnt, PCA env and a phenological matching index (PMI) using global occurrence records, bioclimatic variables and soybean phenology data. Under current climatic conditions, R. pedestris exhibited a predominantly temperate East Asian distribution, with suitable areas extending farther north and northeast. By contrast, N. viridula showed a more southerly and spatially continuous distribution across South and Southeast Asia, with suitability declining markedly toward northern and northeastern Asia. By the 2090s under SSP5-8.5, suitable areas decreased by 26.7% for N. viridula but increased by 34.0% for R. pedestris, and the co-suitable area declined from 9.460 to 7.350 million km2. PCA env indicated low to moderate niche overlap (Schoener’s D = 0.278) with significant niche differentiation. Under fixed soybean calendars, mean PMI generally increased for both pests, although the increase plateaued for R. pedestris under high emission scenarios by the late 21st century. Collectively, these findings indicate that Asian soybean production regions currently face overlapping damage risk, that the potential damage zone of R. pedestris is likely to expand further, and that the temporal overlap between the soybean sensitive period and adult activity windows of both pests will generally increase—despite the projected contraction in the potential damage distribution of N. viridula.