EVALUATION OF DAMAGE BY Spodoptera frugiperda (J.E. SMITH) (LEPIDOPTERA: NOCTUIDAE) AND CHARACTERIZATION OF THE LEAF MORPHOLOGICAL TRAITS IN LANDRACE POPULATIONS OF MAIZE (Zea mays L.)

Background. The fall armyworm Spodoptera frugiperda is one of the most damaging pests of maize in tropical areas. Objective. To evaluate the damage caused by S. frugiperda and the leaf morphological traits in 15 populations of maize landrace. Methodology. The leaf damage caused by S. frugiperda and four-leaf morphological traits (leaf blade thickness, leaf blade hardness, specific leaf area and trichome density) were evaluated at 20, 30 and 40 days after emergence (DAE) in two seasons, dry (March and April) and rainy (June and July). Spearman correlation between the degree of leaf damage and each leaf morphological trait was also evaluated. Results. Maize populations showed differential response to the damage caused by S. frugiperda among seasons and evaluating date. The leaf morphological traits were different between seasons and among evaluating dates. The trichome density had intermediate negative correlation with the level of leaf damage in rainy season (rs = − 0.32, p < 0.001). Implications. The lower leaf damage may be indicator of resistance against S. frugiperda. Conclusion. The population 2020−M62 had low susceptibility to S. frugiperda, this population may be candidate for maize breeding program.