Invasive Stink Bugs and Related Species (Pentatomoidea)

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472 Invasive Stink Bugs and Related Species (Pentatomoidea)


herbaceous weeds around coffee stems as well as on castor oil trees and filaos, Casuarina equisetifolia
L. (Casuarinaceae), which are often associated with Arabica coffee as windbreaks (Wilkinson 1924).
A. thunbergii also has been reported on Chrysanthemoides monilifera (L.) Norlindh (Asteraceae) and
Leucosidea sericea Eckl. and Zeyh. (Rosaceae) (Le Pelley 1942, Greathead 1966b). In the DRC, Lefèvre
and Hendrickx (1942) collected Antestia bugs on forest jasmine, Jasminum abyssinicum Hochst. ex DC.
(Oleaceae) and on Trema orientalis (L.) Blume (Cannabaceae) in the Kivu region. In Cameroon,
A. intricata was collected on Asteraceae such as Vernonia amygdalina Delile, Ageratum conyzoides L.,
Bidens pilosa L., and Amaranthaceae (Achyranthes sp.) (Mbondji Mbondji 1999). In Ethiopia, A. intri-
cata once was recorded on Mauritius thorn, Caesalpinia decapetala (Roth) Alston (Fabaceae), during
the time when green berries were not available on coffee trees (Crowe and Gebremedhin 1984), and on
orange flowers, Citrus sinensis (L.) Osbeck (Rutaceae) (Bayissa and Tadesse 1981).
Rearing of Antestia bugs on some of these plants has been attempted in the past, with limited success.
Best results were obtained in the DRC, where Antestia bugs fed and developed until the fourth instar
on Galinsoga parviflora Cav. (Asteraceae) (Lefèvre and Hendrickx 1942), whereas in Cameroon, some
adults were obtained from nymphs reared on Vernonia amygdalina (Mbondji Mbondji 1999). In the
Ivory Coast, the full development of Antestiopsis intricata was obtained on Solanum anomalum Thonn.
(Solanaceae), which abounds as a weed in coffee plantations (Lavabre 1952). However, because most of
these plants are common within or in close association with coffee plantations, they usually are consid-
ered to be temporary hosts of Antestia bugs.
Authors uniformly agree that coffee, and especially Coffea arabica, is the favorite host plant of Antestia
bugs. In the Ivory Coast and the DRC, Antestiopsis intricata has been found on two additional cultivated
coffee species, C. canephora Pierre ex A. Froehner and C. liberica W. Bull ex Hiern, but these two hosts
are considered occasional because no significant and long-term infestation has been reported for them.
Five wild species in the family Rubiaceae (i.e., Pavetta elliottii K. Schum. and K. Krause, Psychotria
nairobiensis Bremek, Galiniera coffeoides Delile, Vangueria apiculata (Verdc.) Lantz, and Canthium
sp.) are known to be host plants for A. thunbergii in Eastern Africa (Hargreaves 1936, Le Pelley 1942).
These plants allow the development of large populations of Antestia bugs and, because they are common
in environments surrounding coffee, they evidently form reservoirs for reinfestation of coffee plants.


10.3.2.2 Feeding on Coffee


Antestia bug species feeding on coffee plants have similar habits. They feed on flower buds, berries at
different stages of development and maturation, and green shoots and leaves. The feeding preferences
for these different organs are controversial. Most authors agree that green berries, flower buds, and green
twigs are consumed first. Mature leaves and berries with solid beans inside are chosen only if no other
feeding sources are available (Kirkpatrick 1937). Le Pelley (1942, 1968) reported that large green berries
and red berries are preferred, followed by small berries, and then shoots. Foucart and Brion (1959) wrote
that feeding habits of Antestiopsis thunbergii ghesquierei were a crucial parameter of the pest develop-
ment, more important that climate conditions. However, they reported that food preferences varied over
the bug’s development as well as over the year.


10.3.3 Phenology with Descriptions of Developmental Stages


10.3.3.1 Antestiopsis thunbergii


10.3.3.1.1 Egg Stage


Eggs of Antestiopsis thunbergii are 1.2 mm long and 1.0 mm large, white and attached to the substrate by a
secretion of adhesive material. They usually are laid in clusters of twelve (Figure 10.1D). The incubation
period varies greatly with temperature. Because most past rearing attempts were conducted in insecta-
ries at room temperature, the locality, elevation, and period of the year are crucial factors affecting devel-
opment duration. In Kenya, at ≈1800 m asl, Anderson (1919) reported an egg incubation period of 7 to 9
days from January to April and 13 to 15 days from May to December, whereas Le Pelley (1968) reported
an incubation period of 6 to 15 days at mean temperatures from 22.5 to 16.9°C. In Uganda, at ≈1200 m

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