Biological Control of Insect Pests: Southeast Asian Prospects - EcoPort

4.12 Nezara viridula 225
Anastatus japonicus, is known as an egg parasitoid of the gypsy moth
Lymantria dispar and other Lepidoptera (Hokyo et al. 1966b).
KIRIBATI
N. viridula was a pest on the islands of Betio and Tarawa in the 1970s.
T. basalis was released in 1978 and, since 1984, this pest has not been
recorded from Tarawa (E. Dharmaraju pers. comm. 1985).
NEW CALEDONIA
Trissolcus basalis was introduced in 1942Ð43 and became established
(Lever 1943; Clausen 1978).
NEW ZEALAND
N. viridula was first recorded in 1944 and soon became a serious pest of
many crops. T. basalis was introduced from Australia in 1949 and rapidly
became widely established. There followed a gradual decline in the severity
of plant damage and, although populations continued to fluctuate seasonally,
the situation became satisfactory (Cumber 1949, 1951, 1953, 1964). Over
this period T. basalis extended its host range to other pentatomid bugs (e.g.
Cuspicona simplex and Glaucias amyoti), thereby providing a source of
parasitoids to attack any eggs of Nezara that became available. Adaptation
of T. basalis to Nezara under New Zealand conditions may also have been
responsible for its improved performance (Cumber 1964).
Trichopoda pennipes, originally from Florida, was obtained from
Hawaii in 1965 and released over the next 3 summers. Evidence of a
generation in the field was obtained in May 1967, but the fly did not become
established. In addition to Nezara viridula, eggs were deposited on adults of
other pentatomids Antestia orbona, Cermatulus nasalis, Cuspicona simplex,
Glaucias amyoti and Dictyotus caenosus, but a parasitoid was reared only
from G. amyoti whose nymphs are readily parasitised (Cumber 1967).
PAPUA NEW GUINEA
N. viridula is a serious pest in the Markham Valley where T. basalis is
present, but generally results in less than 30% parasitisation. In 1978 a strain
of this parasite from Western Australia was released, but the level of
parasitisation did not increase (Young 1982). In Wau T. basalis and another
scelionid egg parasite are generally effective, although N. viridula
occasionally increases to pest proportions (Gagne 1979). The tachinid
parasites Trichopoda pennipes and T. pilipes were introduced from Hawaii
but failed to become established (J.W. Ismay pers. comm. 1985).
T. giacomelli is being considered for release.
PHILLIPINES
Three decades ago it was reported that N. viridula was not a pest, apparently
being controlled by a native egg parasitoid, Ooencyrtus sp. (Cendana, in
Davis 1967) and it is interesting that Nezara was reported as present, but
unimportant, in 1993 (Waterhouse 1993b). This may possibly be correlated