Chemical plant strengtheners find increasing use in agriculture to enhance resistance against pathogens. In an earlier study, it was found that treatment with one such resistance elicitor, BTH (benzo-(1, 2, 3)-thiadiazole-7-carbothioic acid S-methyl ester), increases the attractiveness of maize plants to a parasitic wasp. This surprising additional benefit of treating plants with BTH prompted us to conduct a series of olfactometer tests to find out if BTH and another commercially available plant strengthener, Laminarin, increase the attractiveness of maize to three important parasitic wasps, Cotesia marginventris, Campoletis sonorensis, and Microplitis rufiventris. In each case, plants that were sprayed with the plant strengtheners and subsequently induced to release volatiles by real or mimicked attack by Spodoptera littoralis caterpillars became more attractive to the parasitoids than water treated plants. The elicitors alone or in combination with plants that were not induced by herbivory were not attractive to the wasps. Interestingly, plants treated with the plant strengtheners did not show any consistent increase in volatile emissions. On the contrary, treated plants released less herbivore-induced volatiles, most notably indole, which has been reported to interfere with parasitoid attraction. The emission of the sesquiterpenes (E)-β-caryophyllene, β-bergamotene, and (E)-β-farnesene was similarly reduced by the treatment. Expression profiles of marker genes showed that BTH and Laminarin induced several pathogenesis related (PR) genes. The results support the notion that, as yet undetectable and unidentified compounds, are of major importance for parasitoid attraction, and that these attractants may be masked by some of the major compounds in the volatile blends. This study confirms that elicitors of pathogen resistance are compatible with the biological control of insect pests and may even help to improve it.

The predatory bug Orius albidipennis (Reuter) (Hemiptera: Anthocoridae) has tremendous potential as a biological control agent, especially in its native range around the Mediterranean Basin and East Africa. The need to exploit native biological control agents is growing in importance as concerns over the introduction of non-native species continue to increase. However, little is known of the effects of different prey on development and reproduction of O. albidipennis compared with other species of Orius. Therefore, we compared the development, survival, reproductive biology, and prey consumption of O. albidipennis when fed eggs of Ephestia kuehniella Zeller, Tetranychus urticae Koch, and Trialeurodes vaporariorum (Westwood), and larvae of Gynaikothrips ficorum (Marchal), under laboratory of 26 ± 1°C, 60 ± 10% RH and 16L:8D photoperiod. Individuals were reared from the neonate stage until death on one of the four prey types. The type of prey had profound effects on all measured performance traits. The highest survival rate was recorded for nymphs that were fed on E. kuehniella eggs, while the lowest survival rate was observed for those fed on T. vaporariorum eggs. The shortest nymphal period was recorded for nymphs fed on E. kuehniella eggs, while the longest was measured for those fed on T. urticae eggs. During the nymphal period, O. albidipennis consumed significantly more eggs of T. urticae than other prey types, whereas the lowest number of consumed prey were eggs of E. kuehniella. Adult females and males consumed significantly more T. urticae eggs than other types of prey. However, Orius albidipennis females showed the highest fecundity when fed on E. kuehniella eggs, and the lowest when fed on T. vaporariorum eggs. Adult females and males that fed on G. ficorum larvae had significantly longer life spans compared with those fed other prey. Because of their relatively rapid development and high fecundity, O. albidipennis fed E. kuehniella eggs had a significantly higher net reproductive rate (R o ) and intrinsic rate of increase (r m ) than O. albidipennis fed other prey types. Overall, eggs of E. kuehniella were the most suitable diet for nymphs and adults of O. albidipennis. Although less suitable, O. albidipennis could survive and reproduce on the other prey types, which is a favourable attribute in biological control agents. These results on the effect of different prey types on development and reproduction of O. albidipennis will also contribute to Handling Editor:

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The Integration BetweenTrichogramma EvanescensWest. (Hymenoptera: Trichogrammatidae) and Selected Bioinsecticides for Controlling the Potato Tuber MothPhthorimaea Operculella(Zell.) (Lepidoptera: Gelechiidae) of Stored PotatoesThe efficacy of the egg-egg parasitoidTrichogramma evanescens(Hymenoptera: Trichogrammatidae) and certain bioinsecticides (e.g., Neemix, Virotecto, Agerin, Dipel 2x and Spinosad) for controlling the potato tuber moth (PTM),Phthorimaea operculella(Zeller) (Lepidoptera: Gelechiidae) under storage conditions was studied. Single and combined treatments ofT. evanescensand the bioinsecticides were tested. Neemix and spinosad were evaluated as spray treatments. Virotecto, Agerin and Dipel 2x were evaluated as dust and spray treatments. Data were recorded in terms of rate of infestation, reduction of infestation, number ofP. operculellapupae, and number of mines per 20 tubers as well as percentage of edible parts. Data revealed that the percentage of infestation in the control treatment was as high as in the Neemix treatment being 96.67 and 90% after one and two months of storage, respectively. Obviously, Spinosad and Dipel 2x were the most effective bioinsecticides in reducing tuber infestation and number ofP. operculellarecovered pupae. Virotecto and Agerin reduced rate of infestation and number of recoveredP. operculellapupae over that of the control, but their effect was significantly lower than that of Spinosad or Dipel 2x. Moreover, there were significant differences among treatments in the form of the number ofP. operculellatunnels and percentages of edible parts after two months in storage. Data further indicated that the integration between the tested bioinsecticides andT. evanescensenhanced the control ofP. operculella.Significant differences in percentages of infestation, edible parts, number of recovered pupae as well as number of mines in stored potatoes existed between individual treatments (withoutTrichogramma) and combined treatments.

A new subgenus and species, Glyptomorpha (Zanporiu) egyptiaca from Egypt, Arabia, Yemen and Pakistan are described and illustrated. G. Zanporia differs from G. Glyptomorpha in the form of the scapus and the lengh of the ovipositor. The status of Teraturus Kokujev is reconsidered and it is proposed that it should be treated as a subgenus of Glyptomorpha Holmgren, The relationship of Glyptomorpha to Rhadinobracon Szépligeti and Victoroviella Tobias is also discussed.

A new genus Mesobraconoides Sarhan & Quicke is described for the species M. psolopterus (Wilkinson) comb. n. (type species) and M. truncatus (Szepligeti) comb. n. Both species have been transferred from Mesobracon. M. psolopterus is here recorded from Sierra Leone as a parasitoid of the pyralid, white rice borer, Maliarpha separatella Ragonot, widespread in the Afrotropical region. M. psolopterus is redescribed and illustrated and a key provided to separate it from M. truncatus.

The toxicity effect of five insecticides (Dipel 2x, Radiant, Proclaim, Aphox and Coragen) on two species of entomopathogenic nematodes (EPNs) (Heterorhabditis bacteriophora BA1 and Steinernema carpocapsae BA2), were evaluated under laboratory conditions at different concentrations 100%, 50% and 25% of field rates (FR). Moreover, the virulence of insecticide-treated EPNs against the l st nymphal instar of the greater wax moth Galleria mellonella L. (Lepidoptera: Pyralidae) was also evaluated. Data indicated that all insecticides showed negative effect on the tested infective juveniles (IJs) of EPNs and the percentages of mortality were in order of H. bacteriophora BA1>S. carpocapsae BA2 and were concentration-dependent; significant differences existed between untreated (control) and insecticide treatments EPNs. Proclaim insecticide recorded the highest mortality rate in EPNs at all tested concentrations 24, 48 and 72 hours post treatment. Regarding the effect of tested insecticides on the virulence and the reproductive capacity of treated EPNs, data indicated that the ability of insecticide-treated EPNs to locate and infect larvae of G. mellonella decreased after exposure to insecticide and consequently reproductive capacity of EPNs was significantly reduced.