Semiochemistry of Pentatomoidea 703
range. Thus, it remains equivocal as to whether the reported responses to linear hydrocarbons represent
a true, biologically relevant aggregation effect. Aldrich (1988) proposed that one of the functions of the
aliphatic hydrocarbons in the gland secretions is to serve as solvents or carriers, rather than as inherently
bioactive compounds, to modulate the evaporation of the other compounds, suggesting a reason for the
relatively large quantities of hydrocarbons found in stink bug glands.
Most pentatomids aggregate upon hatching and then disperse during later stadia. Several authors have
proposed that 4-oxo-(E)-2-decenal might be involved in the aggregation behavior of first instars (Borges
and Aldrich 1992, Pavis et al. 1994, Fucarino et al. 2004). This compound has been identified from
the DAGs of first instar nymphs for Euschistus heros, E. conspersus, E. tristigmus, Thyanta perditor,
T. pallidovirens, Nezara viridula, and Chinavia aseada (=Acrosternum aseadum), and its potential role
as an aggregation pheromone has been demonstrated for Nezara viridula (Pavis et al. 1994, Fucarino et
al. 2004). Among insects, 4-oxo-(E)-2-alkenals have only been reported from the Heteroptera to date.
15.4 Kairomones for Natural Enemies
Parasitoids and predators can exploit the volatile chemicals produced by their hosts as kairomones to
locate their hosts (Tables 15.2 and 15.3). The compounds exploited can include the host’s defensive secre-
tions (Table 15.2), or compounds produced by the host for intraspecific signaling such as sex, alarm,
or other pheromones (Table 15.3). Alternatively, natural enemies may exploit compounds associated
with products derived from the host such as feces/frass, exuvia, scales, honeydew, or host “footprints”,
where the host has no control over the production of the compounds (Vinson 1985, Vet and Dicke 1992,
Godfray 1994, Borges et al. 2003, Afsheen et al. 2008, Fatouros et al. 2008, Laumann et al. 2009, Conti
and Colazza 2012). Each of these types of kairomonal interactions is considered in more detail below.
Natural enemies often have short adult life spans, and hosts may have only a short time window during
which they can be parasitized; therefore, parasitoids need to locate suitable hosts quickly. Platygastrid
wasp parasitoids, for example, prefer to parasitize pentatomid eggs that are less than 72 hours old (Bin
et al. 1993). Therefore, natural enemies need reliable information about the presence of their hosts, and
semiochemicals from hosts or host-related cues can provide such reliable information.
TABLE 15.2
Allomones from Pentatomoidea That Are Exploited as Kairomones by Natural Enemies
Bug Species Chemicals Natural Enemy Species Reference
Coridius janus
(Dinidoridae)
(E)-2-Hexenal, C 8 , C 10 - C 14 and
C 16 linear hydrocarbonsHymenoptera: Formicidae:
Anoplolepis longipesGunawardena and
Herath 1991
Euschistus biformis (E)-2-Hexenal, (E)-2-octenal,
(E)-2-octenyl acetate,
4-oxo-(E)-2-hexenal, (E)-2-
hexenyl acetate
Mantodea: Mantida
Tenedora aridofoliaNoge et al. 2012Euschistus heros Footprints (the bioactive
compounds were not identified)
Hymenoptera: Platygastridae:
Telenomus podisiBorges et al. 2003Euschistus heros,
Dichelops melacanthus,
Nezara viridula
Tridecane, (E)-2-hexenal,
(E)-2-decenal, undecane,
4-oxo-(E)-2-hexenalHymenoptera: Platygastridae:
Telenomus podisi and
Trissolcus basalisMattiacci et al. 1993,
Laumann et al. 2009Nezara viridula (E)-2-Decenal and (E)-2-octenal Hymenoptera: Platygastridae:
Telenomus podisi
Borges and Aldrich
1994
Nezara viridula Nonadecane Hymenoptera: Platygastridae:
Trissolcus basalis
Colazza et al. 2007Pentatomidae 4-Oxo-(E)-2-hexenal, 4-oxo-(E)-
2-decenal, (E)-2-hexenal,
(E)-2-decenal, tridecane
Hymenoptera: Formicidae:
Harpegnathos saltatorEliyahu et al. 2012