The citrus swallowtail Papilio demoleus L. is a serious pest of citrus in many regions of the world. We evaluated the effects of pyriproxyfen, a juvenile hormone agonist, on late-stage larval and pupal development of the pest. Fourth and fifth instars, as well as freshly formed prepupae were treated topically with concentrations of 7.5–60 μg/μl of the juvenile hormone analogue. Effects included prolongation of larval duration, delay in larval–larval and larval–pupal ecdysis, mortality, formation of mosaics with larval, pupal and adult characteristics, decreased and imperfect pupation, and complete inhibition of emergence. These results demonstrate that pyriproxyfen has an adverse effect on the development and metamorphosis of the citrus swallowtail, and further work is recommended, including laboratory and field studies.

A cotton field was used to set up an arena trial for investigating the dose transfer of oil-based ultra-low-volume sprays of Metarhizium anisopliae (Metchnikoff) Sorokin to the cotton bollworm Helicoverpa armigera (Hübner). Two doses of conidia (75 and 50 g/ha, being 3.75 × 1012 and 2.5 × 1012 conidia/ha, respectively) formulated in 2 litres (70:30, kerosene–peanut oil) were applied using a Berthoud ‘Micro Ulva’ to three groups of larvae of cotton bollworms positioned in three rows downwind of a single spray line. Both the distribution of the droplets and the effect of direct contact with spray droplets were quantified. The mean number of droplets decreased from 416 ( ± 60) droplets per cm2 (line 1; 0.4 m) to 45 ( ± 36) droplets per cm2 (line 3; 5 m). To achieve 50% mortality, >10 and >13 days were necessary for 75 and 50 g/ha, respectively. From day 15, the difference in mortality rates was significant between the two treatments. At line 3 (5 m), at 12 days after application, the mortality rate reached 52% for 75 g/ha and 47% for 50 g/ha. The results are discussed in view of optimizing the application of the biopesticides.

The moth Pareuchaetes pseudoinsulata Rego Barros, whose host plant is the invasive alien plant Chromolaena odorata (L.) King and Robinson, was recently discovered in Uson (6° 14′ 30.77″ N, 6° 04′ 41.37″ E), Evbuabogun (6° 15′ 39.33″ N, 5° 38′ 58.29″ E) and Ekae (6° 15′ 34.90″ N, 5° 37′ 19.75″ E) villages in southern Nigeria after its first release as a biological control agent in that country in 1972. The moth seemed to become more abundant as the rainy season progressed. Studies on some aspects of its biology and behaviour were conducted both in the laboratory and in the field. Females laid eggs on the undersides of C. odorata leaves and on the walls of rearing cages. Female pupae were significantly (P < 0.001) larger than the male ones. Also, adult female wingspan was significantly (P < 0.001) longer compared with that of the males. Adults lived for an average of 4.8 ± 0.01 days and they were active at night, when there was good light intensity. Observations on the behaviour and some aspects of the biology and behaviour are discussed.

The impact of vegetational diversity through intercrop and the application of antifeedants were assessed for their ability to reduce the infestation of shoot and fruit borer Leucinodes orbonalis Guen. on eggplant. Intercropping with coriander and fennel reduced the fruit damage to 12–15% compared with the plots with eggplant monoculture. Total yield of intercropped eggplant was significantly higher than the eggplant monoculture yield. Coriander and fennel were found to be equally effective in reducing infestation by L. orbonalis. Neem seed kernel extract (4%) and the neem-based product Neemarin® were found to be more effective in controlling L. orbonalis than ash dust and were lower than the untreated control. The fruit infestation level in the neem treatments (either of them) was 15–16% less than the untreated check. The interaction of intercrop and antifeedant showed that coriander-intercropped eggplant along with foliar spray of Neemarin® significantly reduced fruit damage. In a multiple choice chamber, orientation of female moths to eggplant was significantly reduced in the presence of fennel or coriander. With 38.9 and 37.1 per female, the extent of egg-laying by L. orbonalis on eggplant associated with fennel or coriander, respectively, was significantly less than on sole eggplant (48.4/female).

We selected 50 crystal (Cry) toxins specific to lepidopteran insects. Phylogenetic relationships of whole toxins as well as individual domains revealed that Cry1Jb and Cry1Ac are distantly placed but related to reduced cross-resistance in Helicoverpa armigera. Multiple alignments of Cry1Jb and Cry1Ac amino acid sequences showed significant differences in the composition and length of the loops of domains II and III. This was further confirmed by the superpositioning of 3D structures. cry1Jb and cry1Ac genes cloned in expression vectors were overexpressed in Escherichia coli Castellani & Chalmers, and proteins were harvested. Insect bioassays revealed that the wild-type Cry1Jb and Cry1Ac proteins showed differential specificity to H. armigera (Hübner), Spodoptera litura (Fab.) and Earias vittella F. Chimeric genes were constructed by exchanging the domains between cry1Jb and cry1Ac and overexpressed in BL21(DE3). Substitution of domain III of Cry1Jb with that of Cry1Ac enhanced its activity against H. armigera 7.8-fold. Bioassay of the parental and chimeric toxins against S. litura revealed no activity even at the discriminative dose of 100 μg/ml, but a significant difference in growth was observed. The present results, along with previous domain swapping experiments, suggest that protein engineering not only reveals the mechanism by which endotoxins work, but also generates novel toxins with enhanced toxicity/broader specificity.

The tomato red spider mite Tetranychus evansi Baker & Pritchard is a serious pest of solanaceous plants worldwide. Management of this oligophagous pest in African nightshades has been a challenge to smallholder African farmers due to its high reproductive rate and rapid development of resistance to synthetic pesticides. The aim of the present study was to determine the influence of leaf trichomes on T. evansi by comparing its fecundity and movement on the leaf surfaces of five African nightshade species, namely Solanum sarrachoides Sendter, S. villosum Miller, S. tarderemotum Bitter, S. americanum Miller and S. scabrum Miller. Data were recorded in the laboratory at 23 ± 1°C, 50–70% relative humidity and a 12 h light:12 h dark photoperiod for the effect of trichome type and density of the abaxial leaf surface on mite fecundity. Distances travelled by mites on the leaf surface from the edge of a thumbtack pin inserted on the leaf were also recorded. Different trichomes, glandular and non-glandular types, were identified. There was a significant negative correlation of fecundity and distance walked by mites with the density of glandular trichomes. Significantly fewer eggs were laid on S. sarrachoides in comparison with the other Solanum species. The distance walked by mites was also significantly shorter in this species, indicating that higher densities of glandular trichomes interfere with mite movements. These results suggest that African nightshade genotypes differ in their levels of resistance to T. evansi, which is partially associated with differences in trichome types and their densities.

The objective of the present study was to evaluate the larvicidal potential of the α-amylase inhibitor from the seeds of Macrotyloma uniflorum (Lam.) Verdc. against Aedes aegypti (L.) larvae. Macrotyloma uniflorum α-amylase inhibitor (MUAI) was partially purified using ion exchange chromatography on a carboxymethyl cellulose column. MUAI at concentrations of 20, 60, 100 and 200 ppm was tested against different instar larvae, pupae and adults of A. aegypti to establish its bioefficacy. MUAI showed a strong larvicidal and a moderate adulticidal effect at a concentration of 200 ppm but did not exhibit pupicidal and ovicidal activities. MUAI-treated larvae showed lower α-amylase activity. MUAI also exhibited ovipositional deterrence activity. Dose-dependent mortality was observed, being highest in the first and second instar larvae. The results thus obtained provide a safe and eco-friendly means in the biological control of A. aegypti larvae.

Mass trapping of red palm weevil Rhynchophorus ferrugineus (Olivier) using food-baited pheromone (ferrugineol) traps is a key component of the integrated pest management strategy adopted to combat this pest in date Phoenix dactylifera L. plantations of Saudi Arabia and other Middle Eastern countries. The present study aimed at ascertaining the density at which pheromone traps should be set in the field to mass trap adult R. ferrugineus. Our findings indicate that in plantations with low weevil activity and < 1% infested palms, a trap density of 1 trap/ha is sufficient. In plantations where infestation levels are >1%, 10 traps/ha recorded the best weevil captures. However, in area-wide mass trapping programmes, the pest could be effectively mass trapped at 4–7 traps/ha depending on the resources available.

Availability of non-host food can determine the success of biological control through its effects on parasitoid survivorship. Here, importance of adult food in determining the longevity of Hemiptarsenus varicornis (Girault), a biological control agent of the pest leafminers Liriomyza trifolii (Burgess) and L. sativae Blanchard, was examined by means of laboratory experiments. Male and female H. varicornis lived less than 2 days with only water available. Provision of diluted honey improved the longevity of adult H. varicornis. Females benefited more by feeding on diluted honey than did males, extending their lifetime to around 2 weeks. In another experiment, newly emerged females were fed diluted honey for their first 5 days and with water only for their remaining lifetime. The result showed that both male and female H. varicornis lived no longer than 2 days after diluted honey was withheld, indicating that nutritional reserves that they could store were highly limited. Thus food sources should be continuously available in the environment for their reproduction. The implications of the results are discussed in the context of biocontrol of leafminers in greenhouses.

This study evaluated the potential use of commercial mycoinsecticide formulations against red-gum lerp psyllid Glycaspis brimblecombei Moore in semi-field conditions. Eucalypt seedlings infested with psyllid nymphs were sprayed with different formulations and two concentrations of each product. Conidial deposits were evaluated after spraying for control efficiency. The conidial deposit was affected by the pathogen species and by formulation types. Higher conidial deposits were associated with mycoinsecticide formulation concentrates of lower granulometry and oil dispersion. However, some products with low deposits of conidia were highly efficient against psyllid nymphs. The results showed that the use of entomopathogenic fungi is a promising alternative method for controlling the red-gum lerp psyllid.

Combinations of Bacillus thuringiensis subsp. kurstaki (Btk) and some plant extracts, namely Acacia arabica (Lam.) Willd., Annona squamosa L., Datura stramonium L., Eucalyptus globulus (Labille), Ipomoea carnea Jacq., Lantana camara L., Nicotiana tabacum L. and Pongamia pinnata (L.) Pierre, were studied for their efficacy and synergistic activity against Spodoptera litura (Fab.) larvae. D.stramonium seed extract fortified with Btk recorded highest mean larval mortality of 74.7%, followed by 61% with A. arabica seed extract, 54.4% with N. tabacum leaf extract and 53% with A. squamosa seed extract. Combination of A. arabica seed extract at 25% concentration and Btk resulted in considerable mortality within 24 h. All Btk fortified extracts caused higher larval mortality than with Btk alone, indicating synergistic action except for the A. arabica leaf extract and Btk combination, which showed antagonistic effect.

The circulatory system in insects is formed by a dorsal vessel (heart) that is a tubular structure that pumps haemolymph in the insect body cavity. Up until now, much is known about the structural organization of the heart in certain Brachycera (Diptera) (e.g. Drosophila). In contrast, little information is available regarding members of the Nematocera suborder (e.g. mosquitoes), in spite of their relevance to human health. Considering their importance, details of the heart morphology of six mosquito species (Aedes albopictus, Ae. aegypti, Ae. fluviatilis, Culex quinquefasciatus, Anopheles darlingi and An. aquasalis) were investigated by scanning electron microscopy (SEM). The heart of the adult mosquitoes, both males and females, consists of a dorsal tubular structure in association with pericardial cells located alongside the heart and alary muscles displaying ramifications that extend from the body wall to the heart surface. The SEM analysis also revealed in detail the organization of the heart, including paired valves on the heart wall (ostia). This study provides a detailed analysis of the mosquito heart microanatomy and, in our view, represents a significant contribution towards the understanding of structural–functional relationships associated with the heart of mosquito.

This study was undertaken to provide new knowledge on biodiversity of aphids and their complex of natural enemies in vegetable agroecosystems in Benin. During a 2-year survey (2007/2008 to 2008/2009), aphid species, their host plants and natural enemies were identified from samples collected from 29 vegetable and 22 weed species at 30 vegetable production sites across Benin. A total of 82% of the vegetable species and 12% of the weed species were infested with aphids. Aphis gossypii Glover infested a wide range of the vegetables and occurred on 62% of the species, while Aphis craccivora Koch, Aphis spiraecola Patch, Lipaphis erysimi (Kalt.), Myzus persicae (Sulzer) and Toxoptera odinae (Van de Goot) were collected from a limited number of vegetables, each with a frequency occurrence ranging from 3 to 28%. The weeds Commelina benghalensis L. and Euphorbia hirta L. were common alternative weed hosts for aphids. Common natural enemies were the predators Cheilomenes propinqua (Mulsant), Cheilomenes sulphurea (Olivier) and Ischiodon aegyptius (Wiedemann), the obligate entomopathogen Neozygites sp., and the parasitoids Lysiphlebus testaceipes (Cresson) and Aphelinus ficusae Prinsloo & Neser. Lysiphlebus testaceipes was usually the only primary parasitoid on aphids across the sites and its common host was A. gossypii. From parasitized mummies, five species of hyperparasitoids were collected, the most abundant being Syrphophagus africanus (Gahan). These are the first records of L. testaceipes, S. africanus and A. spiraecola from West Africa. These findings provide baseline knowledge on the aphid fauna of Benin and contribute information for use in the development of sustainable vegetable pest management strategies in the country.

Lepidopteran pests have occurred in eucalyptus plantations in Brazil since 1948, reaching high population levels, reducing tree growth and causing considerable losses in wood production. The control of defoliating caterpillars in eucalyptus forests is complex, mainly due to the large extent of forest plantations and tree height, necessitating the aerial application of chemical or biological insecticides. Due to this complexity, alternative control methods have been proposed, for instance biological control through the use of parasitoids. Trichospilus diatraeae Cherian & Margabandhu, 1942 is a gregarious pupal parasitoid that preferentially attacks species of the order Lepidoptera. This is the first report of T. diatraeae parasitizing pupae of the eucalyptus defoliator Euselasia eucerus Hewitson in Brazil. This parasitoid offers new perspectives for the biological control programmes of this species in eucalyptus plantations in Brazil.

The seasonality and behaviour of tabanids were studied in the Planalto Serrano of Santa Catarina State, Brazil. From March 2007 to February 2009, a total of 915 tabanid flies from 15 species and six genera were collected on an individual horse. The number of tabanid species varied from zero during autumn/winter to ten in summer (December–February). Dichelacera alcicornis Wied. (62.1%) was the most abundant species followed by Chrysops fusciapex Lutz (6.7%) and C. patricia Pechuman (5.9%). Peak catches occurred during the summer (December–March). The landing behaviour varied by genera: Chrysops (100%) preferred the head, Dichelacera (56.3%) the flanks, and Poecilodera (100%), Acanthocera (100%), Tabanus (58.8%) and Fidena (48.7%) the limbs region. This is the first work on tabanids in the Santa Catarina State, Brazil.