Foliar Consumption and Survival of the Fall Armyworm in Landrace Maize Genotypes

Abstract

This study aimed to evaluate the survival and feeding consumption of Spodoptera frugiperda larvae on different landrace maize genotypes and a commercial Bt cultivar, focusing on resistance mechanisms such as antibiosis and antixenosis. Experiments were conducted in a laboratory setting using five maize genotypes (transgenic, Andean purple, red, Xavante, and purple straw). Resistance assays were developed in the laboratory; for survival analysis, leaf sections of corn were offered ad libitum, and the death day of each individual was recorded. Data were analyzed using the Weibull distribution to estimate the mean survival time. For the feeding consumption assay, 2 cm² disks were offered from the basal part of the genotypes in a completely randomized design with 5 replicates and one larva per plot. Survival analysis results showed that landrace genotypes, with emphasis on the Xavante genotype, approached the transgenic maize suggesting moderate to high resistance. These results indicate that genetic diversity in Landrace maize genotypes significantly influences the survival and feeding behavior of S. frugiperda, demonstrating the importance of this genetic material in plant breeding programs for sustainable maize cultivation