Economic injury levels and economic thresholds for Leptoglossus zonatus (Dallas) (Hemiptera: Coreidae) infesting seed maize

BACKGROUND Although Leptoglossus zonatus is considered a secondary pest of maize grown for grain, when grown for seed, this pest can cause significant economic damage. There are no records of management recommendations for this pest. The objectives of this work were to quantify losses caused by L. zonatus to different genotypes used for seed maize production and to estimate the acute toxicity of select insecticides to L. zonatus using different application technologies. The ultimate goal was to calculate economic injury levels (EILs) and develop economic thresholds (ETs) for L. zonatus infesting seed maize. RESULTS EILs and ETs varied, respectively, from 3-8 and 2-6 adults 1,000 plants-1, depending on the genotype insecticide and application technology. Effective control was obtained by using aerial or ground application of λ-cyhalothrin (10.6%) + thiametoxan (14.1%) or permethrin (38.4%) at the rates of 1.48 mL ha-1 and 27.10 mL ha-1, respectively, or ground application of methomyl (21.5%) at the rate of 244.06 mL ha-1. CONCLUSION Maize grown for seed is susceptible to L. zonatus damage during reproductive stages, and the pest densities requiring management vary with genotype, insecticide, and application technology. These results provide significant contributions towards IPM for seed maize.