Abstracts - Antonioni A. C. Moliterno


Antonioni A. C. Moliterno1, Camila B. C Martins1, Daiane Szczerbowski1 , Zawadneak M.A. C2 and Paulo H. Zarbin1*

1 Laboratório de Semioquímicos, Departamento Química - Universidade federal do Paraná, PR, Brazil; acm.moliterno@gmail.com

2Laboratório de Entomologia, Departamento de Patologia Aplicada, Universidade Federal do Paraná, PR, Brazil.

* pzarbin@ufpr.br

Lobiopa insularis (Castelnau, 1840) is a pest of the strawberry culture, as larvae and adults feed on the fruits, damaging them for consumption. The convention control is based on pesticides, causing negative effects on the environment and on man. In this sense, studies on semiochemicals appear as an alternative method of control. We investigated aeration obtained extracts of males and females using a gas chromatograph (GC) and a GC coupled with mass spectrometer (GC-MS); the chemical characterization was based on co-injections of the natural extract with synthetic standards, besides comparisons of Kovats Indices and of GC-MS library. The quantification of compounds was based on an external standard calibration. Results indicated the presence of three male specific compounds, identified as (i) 2-nonanone (RI: 1087), (ii) 2-undecanone (RI: 1296), and (iii) 2-undecanol (RI: 1303). The compounds were produced only during scotophase, in a concentration of 6.03 ± 5.15, 1.37 ± 1.50 and 0.30 ± 0.15 ng per insect, in 24 hours, respectively. The stereochemistry of compound iii was conducted by GC-Chiral chromatography employing a β-ciclodextrine column, which confirmed that males produced a mixture of enantiomers, in a ratio of 3.5:1, of the S:R isomers, respectively. Field tests using pitfall traps were conducted combining the compounds with ripe strawberry, totaling 25 replications. Results showed that the attractivity of insects towards the binary mixture of ketones (2-undecanone and 2-nonanone - T3) differed from control traps (T5), and traps containing 2-undecanone alone (T4), and 2-undecanone combined with racemic 2-undecanol (T2). Catches presented a proportion of 59% males to 41% females (1:0.7), indicating that L. insularis produces an aggregation pheromone. Of all tested treatments, the mixture of 2-undecanone and 2-nonanone (T3) obtained the best results being recommended for the field control of L. insularis. Future studies include tests with different concentrations of T3 in the field (lower, standard and higher).