Avaliação da atratividade de três espécies de moscas-das-frutas (Diptera: Tephritidae) aos compostos voláteis da amendoeira-da-praia, terminalia catappa e produtos comerciais

Abstract

Fruit flies are among the most relevant pests in the world. Due to economic losses caused by oviposition, host fruit becomes unfeasible for consumption and commercialization. Ceratitis capitata, Anastrepha fraterculus, and Anastrepha obliqua are the most economically important pest species for Brazil. Aiming to control these insects, traps containing attractants are applied, which may be associated with toxic baits. Phytosanitary products are used to control this pest. However, it may contain high toxicity and a grace period, in addition to generating a risk of environmental and human contamination. Currently, the high rates of pesticide residues are among the limiting factors for the free export of fruits, together with their infestation by fruit flies. Currently, the high rates of pesticide residues are among the limiting factors for the free export of fruits, together with their infestation by fruit flies. Thus, behavioral control using semiochemicals has been one of the most promising alternatives to monitor and suppress these insects in the field. These compounds have the advantages of being non-toxic, species-specific, ecologically acceptable, and used in small amounts. This work aimed to identify volatile compounds from almond fruit and grape extract and essence that can attract three species of fruit flies. The insects used in the experiments come from the creation maintained at the Laboratory of Behavioral Ecology of Insects - LECI, following the guidelines of the FAO/IAEA. The beach almond extract was obtained by aeration of ripe fruits for 24 hours and subsequent elution of the adsorbent with HPLC grade hexane, followed by sample concentration by nitrogen flow and analysis by GC-MS and GC-EAD bioassay. The extraction of volatiles from commercial products was performed by SPME, followed by analysis by GC-MS. The test of the attractiveness of these compounds was carried out in glass arenas (45cm x 30 cm x 30 cm). Data were analyzed by GLMM in Rstudio software. The characterization of volatile compounds resulted in the identification of 72 compounds present in the extract of the ripe almond fruit, 45 compounds in the glycolic extract of grape, and 13 in the grape essence. The electroantenography bioassay revealed five compounds from the almond extract that elicited response for females of A. obliqua and 4 for females of C. capitata. There were no conclusive results in this bioassay regarding the species A. fraterculus. The active compounds were identified by gas chromatography coupled with mass spectrometry (GC-MS). 1-hexanol, 1-octen-3-ol, ethyl hexanoate, geranyl acetate, and geranyl acetone were active for A. obliqua. For C. capitata the following compounds generated active response, 1-penten-3-ol, isoprenol, 2-buten-1-ol-2-methyl and prenol. The attractiveness test performed in arenas with glycolic extract and grape essence indicated that the glycolic extract of grape has potential attractiveness for males and females, virgins, and copulates of A. fraterculus, p-value <0.05. Grape essence did not show any significant difference in the capture of these insects. These results indicate that females may identify specific compounds, which may contribute to the semiochemicals application in monitoring and controlling these pests in the field.