Investigation on genetic and pheromonal variability of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) Brazilian populations from different locations of the country

Abstract

Many sexual pheromones used for monitoring or controlling important agricultural pests are synthesized starting from insect populations of other countries and not always from Brazilian populations. Previous studies demonstrated that there are differences in the chemical composition among pheromones of distinct and geographically distant populations, what can negatively affect the attractiveness of the compounds. Even the pheromone commercialized in Brazil, for the Fall Armyworm, Spodopterafrugiperda (J. E. Smith) (Lepidoptera: Noctuidae) is not efficient for its monitoring in some Brazilian States, suggesting that distinct populations may occur. This project aims to investigate the genetic and pheromonal variability of Brazilian populations of S. frugiperda from different locations of the country. For that, field populations will be obtained from corn crops, corn and rice races will be separated, the most abundant haplotypes in each population will be identified and selected, and then rearings will be established in the laboratory for the extraction and identification of the pheromone produced by females of each population. These works will be developed at the Instituto Nacional de Ciência e Tecnologia (INCT) de Semioquímicos na Agricultura, from which ESALQ/USP and UFV (Insects Biology and Behavior), UFPR and UFAL (Identification and Synthesis) make part. The steps of this research with S. frugiperda include: (i) collection and identification of the corn and rice races; (ii) characterization of the genetics diversity of the populations; (iii) establishment laboratory rearing; (iv) extraction of the natural pheromones of virgin females; (v) identification of the active compounds in the extract by gas chromatography and electroantennography (GC-EAD); (vi) identification of the compounds by gas chromatography and mass spectrometry (GC-MS); (vii) synthesis; (viii) assays in wind tunnel and validate the use of the pheromone on field. (AU)