Biological Control of Insect Pests: Southeast Asian Prospects - EcoPort

USA
USSR
4.4 Aphis gossypii 69
Lysiphlebus testaceipes parasitised 74.5% of Aphis gossypii on strawberries
and Aphelinus semiflavus a smaller number. Seven hyperparasitoids were
reared (Oatman et al. 1983b). L. testaceipes was considered by Schlinger
and Hall (1960) to be the most effective aphid parasitoid in southern
California and to give excellent control there of Aphis gossypii. At least 8
hyperparasitoid species were also reared (Schlinger and Hall 1960).
Entomopathogen infection was the primary cause of a reduction in
A. gossypii population that occurred during the week after peak aphid
abundance on cotton in Mississippi and continued pathogen activity,
combined with predation, maintained aphids at a low density for the
remainder of the season. Early in the season parasitisation and predation
may have reduced aphid population growth (Weathersbee and Hardee 1993,
1994).
In untreated cotton plots small predators (spiders and Geocoris spp.:
Hemiptera, Lygaeidae) had the greatest impact on A. gossypii populations
and the parasitoid Lysiphlebus testaceipes was never abundant. Fungi killed
many aphids and constituted the most important natural enemy factor in
insecticide treated plots (Kerns and Gaylor 1993). Fungi attacking
A. gossypii in USA include Neozygites fresenii (Steinkraus et al. 1992,
1993a,b,c; Sanchez-Pena 1993, Smith and Hardee 1993) and
Cephalosporium (= Verticillium) lecanii (Sopp et al. 1990, Yokomi and
Gottwald 1988). The coccinellid predators Hippodamia convergens and
Scymnus louisianae, the chrysopid Chrysoperla carnea, and Syrphus sp.
were effective in reducing populations of A. gossypii in Texas (Vinson and
Scarborough 1989). In Alabama the hemerobiid Micromus posticus is an
important predator (Miller and Cave 1987).
In southern USSR coccinellid beetles are important predators of aphids.
Adult Coccinella undecimpunctata and larvae of Hippodamia variegata are
the most voracious and prefer A. gossypii, whereas Coccinella
septempunctata prefers A. craccivora (Belikova and Kosaev 1985).
There are many papers dealing with the control of A. gossypii and
associated pests in glasshouses. The lacewing Chrysoperla carnea was
effective only when released at a predator: aphid ratio of 1:20, whereas
Chrysopa sinica was effective at 1:50 (Shuvakhina 1983). Other predators
utilised include Chrysopa perla (Ushchekov 1989) and the cecidomyiid
Aphidoletes aphidimyza (Begunov and Storozhkov 1986). Under conditions
of high humidity, high aphid mortality was caused by the fungi
Cephalosporium lecanii, Beauveria bassiana and Paecilomyces
fumosoroseus (Pavlyushin and Krasavina 1987).