Alternative control methods for Fall army worm in some agroecologies in Cameroon

Abstract

Maize cultivation in Cameroon faces threats from the fall armyworm (Spodoptera frugiperda), significantly reducing crop yields. This  study explores eco-friendly, safe, and accessible pest control methods. Trials were conducted in Garoua (zone I), Foumbot (zone III), and  Ntui (zone V) using six treatments: Control, Emamectin (RAPAX), Bacillus thuringiensis, Soap, A. indica oil (neem), and Bacillus  thuringiensis + Emamectin. All treatments showed insecticidal effects compared to the control, with Emamectin, Bacillus thuringiensis +  Emamectin, A. indica oil, and Bacillus thuringiensis being most effective. High incidence rates were found in zones I and III (55.82% and  44.17%) versus zone V (34.72%). Significant positive correlations existed between attack severity and incidence (r=0.801), larval numbers  with incidence (r=0.639) and severity (r=0.420), while grain yield had significant negative correlations with incidence (r= -0.736), severity  (r= -0.931), and larval numbers (r= -0.690). Yield analysis showed significant effects (P<0.05) from all treatments compared to control.  Emamectin yielded 2950kg/ha, followed by Emamectin + Bacillus thuringiensis (2783kg/ha). Control treatments yielded 1100kg, while  soap, A. indica, and Bacillus thuringiensis yielded 2257kg/ha, 2607kg/ha, and 2750kg/ha respectively. No significant zone effect was  noted. The study emphasizes balancing economic and efficacy factors in pest control method selection, with neem oil, emamectin  benzoate, and RAPAX suitable for various pest pressures and environmental conditions.