Straw management in sugarcane affects sugarcane billbug (Coleoptera: Curculionidae) dispersal

The prohibition of straw burning for sugarcane harvesting facilitates the accumulation of organic matter in the soil, creating a microhabitat favorable to the survival of pests, such as the sugarcane billbug Sphenophorus levis Vaurie (Coleoptera: Curculionidae). This condition may also modify S. levis behavior, especially dispersal in sugarcane fields. As the inefficiency of the control tactics currently employed has turned this species into a key pest in the crop, straw management could be an alternative to S. levis management. In this study, we evaluated the effect of sugarcane straw management on S. levis dispersal under three conditions: (i) full straw, (ii) windrowed straw in the sugarcane interrow, and (iii) removed straw using the capture-release-recapture technique. The maximum distance traveled by the S. levis varied from 1.5 to 6.7 m in 11 d, depending on straw management, with more restricted mobility when the straw was completely removed. The direction of movement was significantly influenced by straw removal, with a higher number of S. levis recaptured in the same row of sugarcane where insects were released (within-row). Males and females exhibited similar patterns, with greater dispersal activity during the first few days after release. The presence of straw favored the movement of S. levis, whereas its total removal or windrowing restricted its dispersal. Thus, straw removal from sugarcane rows is a potential strategy for managing this pest. These results underscore the importance of cultural management as an integrated pest control strategy.