Effect of belt expert (Flubendiamide plus Thiacloprid), Imidacloprid, Thiamethoxam seed treatment and economic impact on fall armyworm (Spodoptera frugiperda) infestation on Maize in Nigeria

Fall Armyworm (FAW) Spodoptera frugiperda infestation in Nigeria has reduced the yield of maize by over 40%, especially where control measures are not implemented adequately or effectively. The concealed feeding behavior of the larvae in the leaf whorl makes its control with insecticide difficult, especially for older larvae as a high volume of insecticide will be required to reach the hidden larvae. This can increase the potential of pest exposure to insecticide, selection pressure and consequent development of resistance. One of the new control strategies being developed for this pest is the use of new insecticides of a different mode of action; Belt Expert (Flubendiamide + Thiacloprid) applied at a threshold of 20% (11,000 plant samples/ha) infestation. Flubendiamide + Thiacloprid gave yields similar to conventional insecticides (Emamectin Benzoate and Lambda-cyhalothrin + Chlorantraniliprole) which were better than the untreated. Another approach is the use of seed treatments (Imidacloprid, Thiamethoxam, Apron plus) followed by 2 foliar sprays with Ampligo (Lambda-cyhalothrin + Chlorantraniliprole) at 2, 4, 6 and 8 weeks after planting (WAP). Treatment with imidacloprid or thiamethoxam seed treatment flowed with foliar application of Ampligo at 4WAP significantly had the lowest larval count and highest percentage maize grain yield with a significant yield increase of >15% over the untreated. The use of insecticide with a different mode of action in the targeted pest density and a seed management-based approach may be significant in the management of pest resistance. Future works should focus on integrating some of these approaches in the management of FAW in Nigeria.