Síntese dos feromônios de agregação decanoato de metila, (E)-dec-2-enoato de metila, (Z)-oct-2-enal e (2E,4Z)-decadieno-2,4-ato de metila e aplicação para controle de Astylus variegatus e Euschistus h

Abstract

By the environmental imbalance and the increase in monocultures, insect pests have become increasingly frequent and causing serious agricultural problems. Control of these insects was limited until recent years to chemical insecticides that are normally non-selective, causing a negative impact on the nature and human health. Alternative methods have been sought, among them we highlight pheromones, which are applied according to the function, such as: sexual, aggregation, trail, alarm, among others. Thus, this work aimed to synthesize, characterize and field test four compounds (methyl decanoate, methyl (E)-dec-2-enoate, (Z)-oct-2-enal and methyl (2E,4Z)- decadieno-2,4-ate) as aggregation pheromones of the coleopteran pests Astylus variegatus and the stink bug Euschistus heros, which are insects that cause problems in corn, sorghum, beans and vegetable crops. To this end, these compounds were synthesized in two- and three-step reactions with average yields between 64 and 90%, purified by distillation, with their chemical structures characterized by hydrogen and carbon nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR), by highresolution mass spectrometry (APCI-QTOF) and gas chromatography with mass spectrometry detection (GC-MS). For crop field tests, 5 mg of product was used impregnated in individual rubber septa and applied to plates containing entomological glue, which were placed in delta-type traps. These were installed on soybean and porongo crops. 1319 insect pests Astylus variegatus were captured in the soybean crop, 3 Dichelops furcatus insects and 6 Tyanta perditor insects for the porongo crop. The pest bug E. heros was not present in any. [resumo fornecido pelo autor]