CHEMICAL PROFILE OF ORGANIC COMPOUNDS PRESENTED IN THE CUTTLE OF MALES AND FEMALES OF THE SPECIES Pachycoris torridus (SCOPOLI, 1772) (Hemiptera: Scutelleridae) SUBMITTED OR NOT ANESTHETIC PROCEDURE AND IN DIFFERENT TIMES

Abstract

Pachycoris torridus (Scopoli, 1772) (Hemiptera: Scutelleridae) is the main pest of the Jatropha curcas (Linnaeus) (Euphorbiaceae) specie. The study of cuticular compounds of this pest is an alternative for understanding their intraspecific chemical communication in an attempt to develop methods to their behavioral control. This study has as objective to detect variations of the chemical profile of organic compounds contained in the cuticle of P. torridus at different times and extraction method. An adult of each genus of the P. torridus specie, with normal behavior and basic chromatic patterns, was immersed separately in a glass vial (10mL) containing 2mL of HPLC grade hexane bidestilado for 10 seconds (with/without previous anesthesia) and 10 minutes (with/without previous anesthesia), with four replications per treatment. After this time, the extract was gathered and placed in a 1.5mL vial and then in a freezer at -20°C. 1μl aliquots of the extracts (n=32) were analyzed in a gas chromatograph coupled to a mass spectrometry (GC-MS). The chemical evaluation was focused on the concentrations of the volatile compounds [(E)-2-hexenal (E)-4-(oxo)-2-hexenal, (E)-2-hexenil acetate, (E)-2-Octenal, undecane, dodecane, 1-tridecene, unknown, tridecane, (Z,Z)-2,7-octadien1-ol acetate, Tetradecane and Tetradecanal] identified in the extracts. Finally, the cuticular chemical profiles of the major compounds [(E)-2-Hexenal, Tridecane and (E)-4-(oxo)-2-Hexenal] of males and females of the P. torridus specie was the same. As to preparation of extracts protocol, it is recommended to use the immersion of the entire body of the insect at both times (10 seconds and 10 minutes) without anesthesia, in order to enlarge the detection of compounds.