Biological Control of Insect Pests: Southeast Asian Prospects - EcoPort

152 Biological Control of Insect Pests: Southeast Asian Prospects
BRAZIL
Bisexual D. brevipes is present wherever pineapples are grown, but it is not
recorded whether the parthenogenetic strain also occurs. Mealybug wilt was
rare in 1946 and large mealybug colonies uncommon and always covered
with soil mounds built by Solenopsis sp. ants. Sparse green spotting was
general on the leaves of these plants. Natural enemies were numerous and
included Anagyrus sp., Hambletonia pseudococcina and Pseudaphycus sp.
The latter parasitised mealybugs on the aerial parts of the pineapple plant, so
that large colonies were rare. It was never found on colonies under the soil
surface. Its life cycle lasts 14 to 20 days and up to 6 individuals may emerge
from a single host. Predators, mainly coccinellids, were generally present
and attacked the underground mealybug colonies (Carter 1949).
COOK IS
Carter (1973) reported that mealybug wilt of pineapple was a serious threat
to the newly-developing pineapple industry on Atui and Mangaia.
D. brevipes was present, but not D. neobrevipes, and the mealybug was
attended by Pheidole megacephala.
FIJI
D. brevipes is the main pest on pineapple and causes pineapple wiltÑthe
only record in the Pacific outside Hawaii of this condition. It is also a minor
pest of sugarcane. It is controlled to some degree by the coccinellids
Cryptolaemus sp., C. montrouzieri and Scymnus sp. (Lever 1945). Three
chrysopids were predators, including Chrysopa ramburi and C. irregularis
(Lever 1940).
GUATEMALA
Two coccinellid predators of D. brevipes were reported by Carter (1935),
Scymnus bilucenarius was widespread except in highest elevations, but it
apparently exerted little control; and Brachycantha sp. which was
uncommon. A drosophilid fly, Pseudiastata nebulosa, which was heavily
parasitised by two chalcidid wasps, was found and frequently in large
numbers. It was regarded as a promising species for biological control by
Carter (1935), who introduced it to Hawaii in 1932, but the colony died out.
Cecidomyiid predators were very common in the lowlands and occurred
occasionally in the highlands. They attacked large mealybug colonies on
fruit, but were apparently a minor control factor. No hymenopterous
parasitoids were discovered.
GOLD COAST
The parasitoid Pseudaphycus angelicus was reared on D. brevipes in the
laboratory (Anon. 1953) as also was Anagyrus ananatis from California
(Anon. 1957). Both were released in 1953Ð54 and the former became
established. Scymnus sordidus was also introduced from California, reared
on D. brevipes and released, but establishment is not reported (Anon. 1957).