Pheromonal Cross-Attraction in True Bugs (Heteroptera): Attraction of Piezodorus hybneri (Pentatomidae) to Its Pheromone Versus the Pheromone of Riptortus pedestris (Alydidae)

Abstract

We investigated the attractiveness of a synthetic form of the pheromone of the soybean stink bug, Piezodorus hybneri (Gmelin), under field conditions, and compared it with that of (E)-2-hexenyl (E)-2-hexenoate, a pheromone component of a competitor, Riptortus pedestris (Fabricius). Many adult stink bugs were attracted to traps baited with 100 mg of the synthetic pheromone (1: 1: one mixture of β-sesquiphellandrene, (R)-15-hexadecanolide, and methyl (Z)-8-hexadecenoate), but few were attracted to 1 or 10 mg. More than twice as many females as males were attracted to this male-produced pheromone. None of the individual pheromone components (30 mg) attracted conspecifics. In summer (June-July), when field P. hybneri were not in diapause, (E)-2-hexenyl (E)-2-hexenoate was more attractive to P. hybneri than the synthetic pheromone. The sex ratio of the adults attracted to the synthetic pheromone was highly female-biased, yet almost equal numbers of both sexes were attracted to (E)-2-hexenyl (E)-2-hexenoate. Most females attracted to both attractants were mated and had mature ovaries. However, adults attracted to (E)-2-hexenyl (E)-2-hexenoate were likely to have less food in their stomach than those attracted to the synthetic pheromone. In late autumn (October-November), when the bugs were in reproductive diapause, both attractants attracted many sexually immature female and male adults that had well-developed fat body. The synthetic pheromone also attracted a large number of conspecific nymphs. These results suggest that P. hybneri pheromone and R. pedestris pheromone component, respectively, have different functions for P. hybneri. The male-produced pheromone system of P. hybneri seems to be sex-related but to have other roles.

Life History Traits of the Pentatomidae (Hemiptera) for the Development of Pest Management Tools

“…Sex and aggregation pheromones have been identified in approximatively 50 species where the pattern of responses is divided between those that appear to attract only females, and those that attract both sexes, as well as nymphs when this has been tested (Table 1) [16,17,57,58]. The only exception is for Piezodorus hybneri (Westwood); its pheromone appears to be bifunctional, acting either as a sex or aggregation pheromone, depending on the time of the year [59,60]. In comparison, sex-aggregation pheromones have only been identified for a few species (Table 1).…”

The use of the lactone motif in chemical communication

“…132 Besides 118-121, smaller amounts of the unsaturated analogues 123-130 occur possessing a Z-double bond at the u-7 or the u-9 position. 133,134 Lactones 118,119,120,125,126,128,129, and 130 proved to be active in electrophysiological assays using coupled gas chromatography/mass spectrometry. 130 The results showed that large molecules such as the 25 membered ring lactone 129 are volatile enough to serve as a volatile signal.…”

“…125 Field experiments showed attraction only in high doses. 126 Lactone 116 and macrolides 117, 118, and 119 are also constituents of the scent gland secretion of several male Heliconius butteries, i.e. H. melpomene, together with similar uand u-1 macrolides ranging from C 12 to C 20 .…”

Age-related and Individual Variation in MalePiezodorus hybneri(Heteroptera: Pentatomidae) Pheromones

“…Male adults of P. hybneri attract conspecific adults of both sexes [3] via a pheromone comprising β-sesquiphellandrene (Sesq), (R)-15-hexadecanolide (R15), and methyl (Z)-8-hexadecenoate (Z8) [4]. These synthetic chemical mixtures attract conspecific adults, especially females in fields [5]. Our previous study [6] revealed that P. hybneri males produce the pheromone simultaneously with their development to sexual maturity, and that diapausing males produce no pheromone components; thus, the pheromone is likely to play a role in sexual communication.…”

“…The biological function or attractiveness of each pheromone components or its blends for P. hybneri is largely unknown. In fields, each P. hybneri pheromone component alone lacked the attractiveness, while three-component mixture was attractive to P. hybneri [5]. Leal et al [4] showed that the full three-component mixture was attractive more than the any binary mixtures in laboratory conditions, whereas the attractiveness of the different blend ratios has never been investigated.…”