Artificial baits treated with imidacloprid or Beauveria bassiana (Bals.-Criv.) Vuill. reduce damage by Sphenophorus levis Vaurie, 1978 (Coleoptera: Curculionidae) in sugarcane

Abstract

The sugarcane weevil, Sphenophorus levis Vaurie, 1978 (Coleoptera: Curculionidae), causes severe damage to the basal portion of sugarcane stalks, and its management is limited by the low efficiency of conventional soil-directed control methods. This study evaluated the effectiveness of solid artificial attractive baits treated with imidacloprid or Beauveria bassiana (Bals.-Criv.) Vuill., applied at different densities, in reducing damage caused by S. levis in a commercial sugarcane field. The experiment was conducted in Mineiros do Tietê, São Paulo State, Brazil, using a randomized block design with six treatments and five replicates under commercial field conditions. Evaluations were performed at 0, 7, 15, 30, 45, and 60 days after the beginning of biweekly bait distribution, assessing the percentage of damaged stalk bases and the number of immature stages and adults per meter. From 30 days onward, baits treated with imidacloprid (50 and 200 baits ha⁻¹) and B. bassiana (100 and 200 baits ha⁻¹) promoted significant reductions in damage compared with the untreated control, with more consistent effects observed at 60 days. Counts of larvae, pupae, and adults were low throughout the experimental period, supporting damage assessment as a sensitive indicator of treatment effectiveness. The results demonstrate that solid artificial baits, particularly those treated with B. bassiana, represent a viable and operational alternative for integrated management of S. levis in sugarcane.