Environmental drivers of Lygus species distribution in faba bean fields across Saskatchewan (2019–2023)

This study evaluates the incidence and severity of Lygus infestations in faba bean fields across Saskatchewan from 2019 to 2023. Surveys were conducted in collaboration with Saskatchewan Pulse Growers, the Saskatchewan Ministry of Agriculture, and the Entomology Laboratory of the University of Saskatchewan. Lygus insects were collected using standard sweep nets at BBCH 72 stage of faba bean growth. Environmental data, including cumulative degree days, total precipitation, and geographical variables, such as soil climatic zones and crop district, were integrated to assess their influence on Lygus species composition and abundance. Statistical analyses, including PERMANOVA and non-metric multidimensional scaling, revealed that year significantly influenced Lygus community composition, accounting for 22.77% of the variation. A significant interaction between year and crop district explained 40.74% of the variation. Generalized linear mixed models showed species-specific responses to environmental factors: Lygus lineolaris showed a significant association with cumulative degree days and total precipitation, while Lygus borealis and L. elisus responded more to soil climatic zones and precipitation. In contrast, Lygus keltoni exhibited weaker responses to both temperature and precipitation. This study highlights the complex relationships between climate, geographic conditions, and species distribution, providing valuable insights for improving Lygus management in faba bean crops.