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Anagyrus mangicola Noyes, a primary parasitoid of the mealybug Rastrococcus invadens Williams, a pest of fruit crops in West Africa, was studied under controlled conditions at 27°C and 75% r.h. Data are given on the larval stages, their morphology and duration of immature development. The sex ratios of emerging parasitoids, adult longevity, host stage preference, the relationship of the size of the emerging parasitoid to host stage and development time are also investigated.

Between 1908 and 1959, the predatory coccinellid, Hyperaspis pantherina Fürsch, was released for the biological control of the ensign scale Orthezia insignis Browne in Hawaii, four African countries and Peru. Substantial control was reported after all the releases, although the outcome was disputed in Malawi. Other coccinellid species and predatory Diptera were released against Orthezia spp. in various programmes from 1952 to 1977. In most cases these agents failed to establish, and there were no reported effects on the target Orthezia spp. In 1993, H. pantherina was released in St Helena for the control of O. insignis on the endemic gumwood tree, Comm idendrum robustum (Compositae). Preparatory investigations for this release revealed that the taxonomy and biology of this biocontrol agent were poorly known. Hyperaspis pantherina is redescribed and shown to be the correct name for the species previously known incorrectly as H. jocosa (Mulsant). Hyperaspis laeta Gorham and H. levrati (Mulsant) are transferred to the genus Cyra Mulsant (comb. n.). Hyperaspis metator (Casey) (stat. rev.) is resurrected from synonymy with H. levrati auctt. Studies of the life history revealed that H. pantherina normally lays its eggs directly onto the adult female O. insignis and that the first two instars of the larvae are frequently passed inside the ovisac of the female host, after which the host itself is often consumed. The information on the biology and taxonomy of H. pantherina, together with details of culturing methods, should facilitate the further use of this agent for the classical biological control of O. insignis, a pantropical pest.

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Background and aimsPost-mining landscapes are often lacking in a self-sustaining plant community and in a functional belowground microbial community. Inappropriate management of soil can hinder ecological restoration of mine sites. However, the potential role of microbial inoculants and plant nutrient-acquisition strategies in improving mined substrates and facilitating mine-site restoration remains relatively unexplored. We tested (1) whether a commercially-available microbial inoculant was effective in restoring biological properties of mined substrates, and (2) the effect of plant nutrient-acquisition strategies on improving the chemical properties of mined substrates for the growth of native plants.MethodsWe conducted a six-month glasshouse experiment, growing six native plant species with different nutrient-acquisition strategies and adding a commercial microbial inoculant in three substrates (topsoil, magnetite tailings and a combination of both) from an iron-ore mine site in mid-west Western Australia.ResultsThere was no significant improvement in plant growth by adding a commercially-sourced microbial inoculant. Soil microbial biomass carbon and nitrogen increased significantly after plant growth (main effect of species * inoculation interaction). The non-mycorrhizal disturbance-specialist plant species Maireana georgei was effective in improving hostile conditions of the tailings.ConclusionsOur results indicate that re-vegetating stockpiled topsoil using local keystone species is a desirable practice that can improve soil biological properties and benefit mine-site restoration. Commercially-available agricultural-based microbial inoculants may not be compatible for mine-site restoration using native plants, but future research using indigenous soil microbes is warranted. We recommend selecting native plant species with different nutrient-acquisition strategies and complementary traits (e.g., N-fixing and P-mobilising) when restoring mined substrates.