Biological Control of Insect Pests: Southeast Asian Prospects - EcoPort

4.2
Anomis flava
A. flava is regarded as of only minor importance in the Pacific, which is
not surprising since none of its major larval host plants is of much economic
importance there.
Natural enemies
Those reported in the literature are listed in Table 4.2.2.
Egg parasitoids are Trichogramma spp., which on occasion can be
effective: in Mali, 92% parasitisation by Trichogramma sp. was recorded in
untreated cotton (Pierrard 1970), 12.1% to 15% in the Philippines (Ferino et
al. 1982a) and 60 to 80% of eggs on cotton were attacked by T. dendrolimi in
China (Wang et al. 1985, 1988).
As for larval parasitoids, Apanteles anomidis parasitised 27.5% in China
(Xie 1984), Aleiodes aligharensi and Aleiodes sp. together 5.2% in Chad
(Silvie et al. 1989), Charops bicolor 10.2% in China (Xie 1984), Meteorus
pulchricornis 4.9% in China (Xie 1984), Meteorus sp. 50 to 69.4% in Nepal
(Neupane 1977) and Winthemia dasyops 2.5% in Chad (Silvie et al. 1989).
Most other records did not indicate effectiveness or, if they did, it was lower
than 2.5% parasitisation.
A. flava pupae are attacked by at least 5 species of Brachymeria
(Chalcididae). In Madagascar, B. multicolor and B. tibialis parasitised 98%
of pupae in some fields (Steffan 1958).
Further details are provided in the country summaries. It is not easy to
discern a pattern from these although, under some conditions, parasitoids are
clearly able to have a major impact on A. flava populations.
Less is known about the effectiveness of predators, although pentatomid,
carabid, coccinellid, vespid and spider predators have been reported and the
Indian mynah bird consumed large numbers of larvae when they were
abundant (Khan 1956).
Unexplained disappearance of larvae is often attributed to predation,
although heavy rainfall may sometimes be responsible.
Bacillus thuringiensis has been recorded in the field from A. flava larvae
(Yin et al. 1991) and has given promising control on a number of occasions
(Angelini and Couilloud 1972; Delattre 1973; Anon 1976b; Wilson 1981;
Chen et al. 1991).
Both granulosis and polyhedrosis viruses have been recorded in the field
(Table 4.2.2) and it is possible that virus preparations might be used for
control.
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