Damage of Spodoptera frugiperda (Smith) in different maize genotypes cultivated in soil under three levels of aluminium saturation

This study was conducted to assess the damage caused by artificial infestation by the fall armyworm Spodoptera frugiperda (J. E. Smith) larvae in Al-tolerant and Al-susceptible maize cultivars at different levels of Al saturation (low, medium and high) in an acid soil. The experiments were conducted in the field, in Sete Lagoas, MG, Brazil, during four consecutive years in plots corrected with lime, according to the soil analysis to provide three levels of aluminum saturation: toxic (m>50%), intermediate (m<20%), and without aluminum (m<5%). Three maize cultivars were used, BR 201 tolerant (hybrid with yellow endosperm), BR 400 (yellow sweet maize) and BR 451 (High Quality Protein Maize, white endosperm) sensitive to toxic levels of Al saturation, respectively. The treated plots were artificially infested with young larvae. The non-infested plots were maintained free from natural infestation of the fall armyworm using granular insecticide applied directly to the whorl. Yield reductions due to fall armyworm larvae were 57.6, 28.9 and 21%, when the attack was on BR 400, BR 451 and BR 201, respectively. There was no interaction between levels of aluminum and genotype or fall armyworm infestation.