Semiochemistry of Pentatomoidea 693
adults and nymphs in the naturally occurring ratio of 1.4:1, and all blends generally were more attrac-
tive than either single component (Weber et al. 2014b). Mixed-isomer preparations of 10,11-epoxy-1-
bisabolen-3-ol synthesized from (R)-citronellal (identical to lures for H. halys, see Leskey et al. 2015b)
also were attractive to both adults and nymphs, and presence of the collard host plant increased attraction
(Weber et al. 2014b). Cabrera Walsh et al. (2015), using marked adults, showed that whereas collard plants
baited with mixed-isomer preparations of 10,11-epoxy-1-bisabolen-3-ol synthesized from (R)-citronellal
attracted more bugs than unbaited plants, they did not retain them any longer than unbaited plants.
Given the importance of retention of target insects in a trap crop (Holden et al. 2012), these findings
have important implications for use of M. histrionica aggregation pheromone in trap-cropping schemes.
Murgantia histrionica is a specialist on plants in the families Brassicaceae and Capparaceae.
Isothiocyanates are produced by breakdown of glucosinolate compounds within these plants and, also
are sequestered by the bugs, rendering them distasteful and repellent to predators as reflected by the bugs
in their aposematic coloration (Aliabadi et al. 2002). At least two common isothiocyanates—allyl and
benzyl—are attractive to M. histrionica adults, and these plant volatiles may add to the attractiveness of
the mixed-isomer murgantiol lures (Weber et al. unpublished).
- 2 .11 Nezara viridula (L.) and Nezara antennata Scott
[Pentatomidae: Pentatominae: Nezarini]
Nezara viridula is an important agricultural pest in warmer regions worldwide. It is thought to have
originated from east Africa, with host plants in more than 30 plant families (Capinera 2001). The major
pheromone components were identified as a mixture of trans-(Z)-bisabolene epoxide ( 2 , Figure 15.1) and
the corresponding cis-isomer 1 (Figure 15.1) (Aldrich et al. 1987, Baker et al. 1987). Cribb et al. (2006)
described the unicellular glands on the abdominal sternites from which the pheromone is released. The
pheromone attracts adults of both sexes and nymphs in the field (reviewed in Millar 2005). Females are
attracted from a distance by the male-produced pheromone and then once on the same substrate, both
sexes use substrate-borne vibrational signals and visual signals in shorter-range mate location and court-
ship (Čokl et al. 2007, Zgonik and Čokl 2014). Tillman et al. (2010), using yellow pyramid traps topped
with clear chambers baited with a 3:1 trans- to cis-(Z)-bisabolene epoxide blend and containing a pyre-
throid insecticide, showed that N. viridula can be trapped under field conditions, and that this attraction
is dose-dependent. Shimizu and Tsutsumi (2011), using caged male bugs as lures with water pan traps,
showed that N. viridula and N. antennata males attracted males and females of both species. Nezara
antennata is native to Asia and is known to mate with N. viridula where they are sympatric. Dissections
of N. antennata males and females attracted to N. antennata males showed that almost all were pre-
reproductive and not well-fed, leading Shimizu and Tsutsumi (2012) to conclude that the adults might
use the volatiles emitted by adult males as cues to find food.
15.2.12 Oebalus poecilus (Dallas) [Pentatomidae: Pentatominae: Carpocorini]
The small rice stink bug, Oebalus poecilus, is one of the most important rice pests in South America
(Panizzi 1997) along with other Oebalus spp. and Tibraca limbativentris (see below). De Oliveira et al.
(2013) showed that O. poecilus males produced an attractant pheromone, which was identified as one of
the isomers of 1,10-bisaboladien-3-ol (= zingiberenol) by comparison with authentic standards synthe-
sized from both enantiomeric citronellals using Hagiwara’s method (Hagiwara et al. 2002). To determine
the absolute configuration, the male-produced compound was dehydrated to zingiberene, the retention
time of which on a chiral stationary phase β-DEX 325 column matched that of the known (-)-(6R,7S)-
zingiberene (Figure 15.9) from ginger oil (Soffer and Burk 1985, Bhonsle et al. 1994,), proving the
(6R,7S)-configuration. De Oliveira et al. (2013) also found that zingiberenol from O. poecilus coeluted
with less polar diastereomers of (7S)-1,10-bisaboladien-3-ol synthesized from (S)-citronellal on a DB-5
column. Thus, de Oliveira et al. (2013) recorded the^13 C NMR spectrum of a two-component mixture
of the less polar (7S)-1,10-bisaboladien-3-ols and found that the resonances of the quaternary carbons
bearing hydroxyl and methyl groups were very similar to those in the^13 C NMR spectrum of (1R,4R)-
menthenol (Figure 15.9), suggesting that the relative configurations of the two molecules were the same.