Biological Control of Insect Pests: Southeast Asian Prospects - EcoPort

74 Biological Control of Insect Pests: Southeast Asian Prospects
The care needed in selecting a biotype appropriate to the target pest is
also illustrated by the following example. A. colemani from Aphis nerii
mummies on a garden plant (Tweedia coerulia) in Canberra was readily
reared for some generations in an insectary on the banana aphid Pentalonia
nigronervosa before release in Tonga for biological control of that species. It
has not been recovered from the banana aphid, but is now well established on
A. gossypii attacking cucurbits (Carver et al. 1993; Wellings et al. 1994).
When P. nigronervosa colonies are small they are mainly located deep in the
leaf sheaths and they only extend into more exposed areas as they increase in
size. Stadler and Všlkl (1991) found that Lysiphlebus testaceipes searched
mainly in exposed areas for hosts, whereas A. colemani searched both
exposed and concealed areas. This suggests that A. colemani would be the
more appropriate of the parasitoids for hosts in concealed situations and,
interestingly, it has been reported from P. nigronervosa in the field in
northern New South Wales (M. Carver pers. comm.), where it is rare and was
not encountered in recent searches (P.W. Wellings pers. comm.).
A. colemani (often under one of its synonyms) has been introduced to
several countries for the biological control of a range of aphid species (Starù
1975).
Aphidius gifuensis Hym.: Aphidiidae
This species is native to the Oriental region. Details of its fecundity,
oviposition period and longevity are provided by Fukui and Takada (1988).
Aphidius matricariae Hym.: Aphidiidae (= A. phorodontis)
This species is native to the temperate zones of the Palearctic region and has
been recorded from more than 40 aphid species in Europe, North Africa, the
Middle East, Israel, Mongolia and North and South America. It has a
preference for the green peach aphid Myzus persicae in Israel (Rosen
1967a,b) and California (Schlinger and Mackauer 1963). After contact with
honeydew or an aphid host the time spent in searching that region for hosts
increased (Masum 1994).
Ephedrus persicae Hym.: Aphidiidae
This is an almost cosmopolitan species, which is probably native to the
Middle East or Central Asia, and now occurs in the Far East, Europe, South
Africa, Madagascar, Australia and North America. It prefers leaf-curling
aphid hosts, mainly belonging to the Myzinae and, less frequently, to the
Aphidinae (Aphis spp.) (Mackauer 1963, 1965; Starù 1966). A review of the
taxonomy and biology of Ephedrus persicae and E. plagiator is provided by
GŠrdenfors (1986).