Copulation behaviour of Helopeltis bakeri Poppius (Hemiptera: Miridae) under laboratory conditions.

Abstract

There is interest in exploring biodegradable chemicals, e.g. sex pheromones, in behaviour manipulation to control the polyphagous mirid species Helopeltis bakeri Poppius. Understanding this insect pest's reproductive behaviour is critical for identifying and isolating semiochemicals. H. bakeri rate of sexual maturation was determined by identifying the time the winged adult changed colour after the 5th and final nymphal form. We verified that there was no significant difference in the rate of colour change for both sexes. Copulation lasted an average of 167.0 ± 77.1 min and was observed on mating pairs >72 h old from the time of final molt. Close-range copulation behaviour of H. bakeri was recorded using the Behavioral Observation Research Interactive Software, and sequential behaviour analysis was performed by creating adjacency matrices. The ethograms revealed the absence of specific calling behaviour from either of the sexes. However, the male's active pursuit of the female may indicate the latter's role in releasing sex attractants. Using a wind tunnel, it was observed that the number of male visitations of 96-h to 120-h-old females significantly differed from the attraction in younger females (p < 0.05) and peaked from 2:00 PM to 12:00 AM. This supports the crepuscular nature of this mirid species. The difference in the sex maturation age and maximum male attraction implies that the secretion of sex attractant could happen after the completion of development, i.e. the exhibition of colour dimorphism.