The CLIMEX model for matching climates in ecology is used to forecast the favourableness of the Australian environment for Diuraphis noxia (Mordvilko). Parameters used in CLIMEX for D. noxia were derived from the literature and tuned by iterative matching with the known distribution of the aphid in North America. These fitted values were then validated using the known distribution of D. noxia in southern Africa, and with the country-by-country occurrence of the aphid around the world. The results suggest that the drier inland parts of the Australian wheat belt would be very favourable for D. noxia growth and survival. A computer model of the interactions between climate, wheat growth and the biology of D. noxia was then used to simulate the likely infestation rates and potential yield reductions at selected sites in both the summer and winter rainfall regions of the Australian wheat belt. The results indicate that D. noxia has potential to cause severe losses to the wheat crop should it arrive in Australia.

The primary object of the work which is the subject of this paper was to clarify the confusion that has existed for many years in the nomenclature and taxonomy of certain important Agrotid borers of graminaceous crops in Africa.

The genera involved are Spcia, Sciomesa, Poeonoma, Conicofrontia, Bussecla and Sesamia, and of these the first three are new and are described and the others are redescribed. A key to the genera and keys to the species of Sciomesa, Poeonoma and Sesamia are given. The genus Speia is erected for Phalaena vuteria Stoll; the name vuteria Stoll has been wrongly applied to the important pest of sugar-cane in Mauritius, which is, in fact, the well known Sesamia calamistis Hampson. Sciomesa is erected to contain three species previously included in Conicofrontia. Poeonoma also contains three species, of which one is Phragmatiphila serrata Hampson and the other two are new. Hampson's species Conicofrontia sesamoides is redescribed in Conicofrontia and is the only species of that genus dealt with in detail; Phragmatiphila bipartita Hampson is synonymised with it. In the genus Busseola, only the well known pest, B. fusca (Fuller) is described.

The fruit fly genus Ceratitis (Diptera: Tephritidae) comprises several important pest species attacking a wide range of unrelated fruits. This is the second paper in a series revising this genus, and deals with representatives of the subgenus Ceratalaspis. Thirty-six species are recognized, of which five are described as new: C. sucinisp. n., C. hancockisp. n., C. neosticticasp. n., C. paradumetisp. n. and C. mlimaensissp. n.Ceratitis pycnanthi (Ghesquière) is considered to be synonymous with C. striatella Munro, and the possible synonymies of C. giffardi Bezzi and C. sarcocephali (Bezzi) with C. cosyra (Walker), as well as C. lineata (Hering) with C. striatella Munro are discussed. Lectotypes are designated for the following species: C. connexa (Bezzi), C. discussa Munro, C. divaricata (Munro), C. dumeti Munro, C. lentigera Munro, C. lunata Munro, C. marriotti Munro, C. melanopus (Hering), C. parinarii (Hering), C. quinaria (Bezzi), C. scaevolae (Munro), and C. simi Munro. A key is provided, with illustrations of mesonotal and wing patterns and shape of aculeus tip. All species are Afrotropical and most are restricted to the sub-saharan region, except for C. quinaria which is also known from the Middle East (Yemen). Distribution and known host plant data are given. Tentative species groups within the subgenus are discussed.

Saliva was obtained by applying capillary tubes to the mouthparts of the cattle tick, Boophilus microplus (Can.), after the subcuticular injection of pilocarpine hydrochloride. Acid-lipid extracts of this saliva showed prostaglandin (PG)-like activity on bioassay. Chromatographic studies confirmed this activity as being due to PGE2. Extracts from homogenates of B. microplus larvae and salivary gland tissue also showed prostaglandin-like activity. A role for PGs in B. microplus feeding mechanisms is discussed.

Larvae of Pieris brassicae (L.) were reared very successfully on a semi-synthetic diet containing a small amount (1·4% by wt.) of dried powdered green Brassica leaves. At 20°C., development of newly hatched larvae to the time when 50 per cent, had pupated took an average of 23 days, as compared with 21 days for larvae fed on fresh cabbage leaves. Pupal weights and emergence of adults were normal. The cabbage-leaf powder could be omitted if it was replaced by sinigrin and linseed oil, but on this diet development was prolonged by a further one or two days and the average pupal weights were lower. It seems likely that the stocks could be maintained indefinitely on either of these diets. The larvae made satisfactory growth on standard diet which had been stored at – 20°C. for two months.

The tobacco whitefly, Bemisia tabaci (Gennadius), causes severe crop losses in many agricultural systems. The worst of these losses are often associated with the invasion and establishment of specific whitefly biotypes. In a comprehensive survey of biotypes present in central China between 2005 and 2007, we obtained 191 samples of B. tabaci from 19 districts in Hubei province and its surrounds. Biotypes were identified by RAPD-PCR and by sequencing the mitochondrial cytochrome oxidase I gene (mtCO1). We determined that these central Chinese haplotypes included the world's two most invasive B. tabaci biotypes (B and Q) and two indigenous biotypes (ZHJ1 and ZHJ3). The B biotype shared >99.7% identity with other Chinese B biotypes and the Q biotype shared >99.5% of its identity with Q samples from the Mediterranean, USA, Africa and East Asia. By 2007, the Q biotype was dominant over much of Hubei province and appeared to be supplanting all other biotypes, although both the invasive and indigenous biotypes existed in sympatry in some regions. The invasion and rapid establishment of the Q biotype in China mirrors events elsewhere in the world, and we suggest that this is a consequence of its reproductive isolation, its polyphagous nature and its broad-spectrum resistance to insecticides. Its dominance has severe implications for the sustainability of some insecticide groups and for the production of a number of crops.

The responses of female Aedes aegypti (Linnaeus) to a variety of stimuli were studied using an olfactometer bioassay. Mosquitoes responded significantly to convection currents produced by a human hand. The addition of water vapour to convection currents enhanced significantly the mosquitoes' response. Lactic acid, either alone or in combination with water vapour or/and convection currents however, did not increase the response level. Sweat extract elicited higher response than convection currents, water vapour and lactic acid. Human hands elicited significantly higher responses than any other stimuli. The presence of active chemicals other than lactic acid in human odour extract is discussed.

Natural populations of four species of the Anopheles gambiae complex occurring in southern Africa were sampled and individuals identified using ovarian polytene chromosomes (19 species A, 190 species B, 140 species C and 54 A. merus Dön.). The genotypes of these same insects were scored for three loci coding for non-specific esterases, and one locus coding for tetrazolium oxidase, after electrophoresis. There is no intra-specific variation at the tetrazolium oxidase locus; species A, B and C share a common allozyme and A. merus is unique. The relative gene frequencies for the 16 allozymes of the three esterase loci for each species give a minimum probability of correct identification of 0·9533 under the worst conditions of sampling, i.e., where samples consist of equal mixtures of species. In practice, resort to such probabilities is necessary only in the discrimination between species A and C. This system of identification is superior to the chromosome method because all adults, whether male or female, and at whatever stage of the gono-tropic cycle, are identifiable.

A rapid technique is described for characterizing and monitoring, in single insects, the insensitivity of acetylcholinesterase (AChE) to organophosphorus and carbamate insecticides. Ninety-six insects are homogenized simultaneously in a microtitre plate and portions (e.g. 0·05 for Musca domestica L.) assayed colorimetrically with acetylthiocholine in the presence and absence of diagnostic concentrations of insecticide. Reactions are monitored by a kinetic microplate reader linked to a microcomputer that determines mean AChE activities automatically by linear regressions of absorbance-time data. Mean inhibited activity is then expressed as a percentage of uninhibited activity. Several inhibitors can be tested against the same insect to yield an ‘insensitivity profile‘ of individuals and strains. In tests on M. domestica adults of known AChE genotype, the assay clearly distinguished not only between a sensitive and two slightly (3-15-fold) insensitive AChE variants but between all six genotypic combinations of these three alleles.

The establishment and survival of larvae of Chilo partellus (Swinh.) on two sorghum cultivars in the six days after hatching was investigated in the field in India. During this period relatively few larvae are present outside the whorls of the plants, and the numbers present six hours and three days after hatching are proportional to the numbers hatching. The number of larvae in the plants declines during these first three days, but subsequently is stable. Some dispersal to adjacent plants occurs during this period and, at the plant spacing used, approximately seven plants were infested by larvae from a single egg-mass of 40 eggs. The relative susceptibilities of the two cultivars, IS 1151 and IS 2205, altered with the age and size of the plants. This is a vulnerable period in the life-history of the insect and attention should be focused on it in developing resistant cultivars, but because the susceptibility of the plants changes with age it is important to decide the age at which protection would have the greatest economic value.

Only pyrethroid insecticides have so far been recommended for the treatment of mosquito nets for malaria control. Increasing resistance of malaria vectors to pyrethroids threatens to reduce the potency of this important method of vector control. Among the strategies proposed for resistance management is to use a pyrethroid and a non-pyrethroid insecticide in combination on the same mosquito net, either separately or as a mixture. Mixtures are particularly promising if there is potentiation between the two insecticides as this would make it possible to lower the dosage of each, as has been demonstrated under laboratory conditions for a mixture of bifenthrin (pyrethroid) and carbosulfan (carbamate). The effect of these types of treatment were compared in experimental huts on wild populations of Anopheles gambiae Giles and the nuisance mosquito Culex quinquefasciatus Say, both of which are multi-resistant. Four treatments were evaluated in experimental huts over six months: the recommended dosage of 50 mg m−2 bifenthrin, 300 mg m−2 carbosulfan, a mosaic of 300 mg m−2 carbosulfan on the ceiling and 50 mg m−2 bifenthrin on the sides, and a mixture of 6.25 mg m−2 carbosulfan and 25 mg m−2 bifenthrin. The mixture and mosaic treatments did not differ significantly in effectiveness from carbosulfan and bifenthrin alone against anophelines in terms of deterrency, induced exophily, blood feeding inhibition and overall mortality, but were more effective than in earlier tests with deltamethrin. These results are considered encouraging, as the combination of different classes of insecticides might be a potential tool for resistance management. The mixture might have an advantage in terms of lower cost and toxicity.

A comparative analysis was performed on 18 mitochondrial DNA sequences, or haplotypes, of Lutzomyia (Nyssomyia) whitmani (Antunes & Coutinho) isolated by PCR from 28 individual flies originating from 10 Brazilian locations 150–2500 km apart. A phylogenetic analysis using maximum parsimony indicated support for three to four major lineages (Outgroups were haplotypes of Lutzomyia (Nyssomyia) intermedia (Lutz & Neiva)). One L. whitmani lineage was found in the Atlantic Forest zone of the North East, including the species' type locality, and is distinct from a second monophyletic group of haplotypes located in the drier interior of Brazil, stretching from the Tropic of Capricorn to Teresina just outside Amazonia. This provides no support for a previous hypothesis that L. whitmani sensu stricto is a single form widely-distributed south of Amazonia, and characterized by derived anthropophilic and synanthropic behavioural traits. The ranges of both lineages include populations incriminated in the peri-domestic transmission of Leishmania braziliensis sensu stricto. A third, Amazonian, group of haplotypes was less well-defined. It appears to consist of two sub-lineages which, like the two Leishmania species associated with them, are strictly silvatic and are separated by the Amazon floodplain. The zoophily of the Amazonian populations was not shown to be an ancestral trait. The geographical distributions of the Brazilian lineages are concordant with the broad patterns of bioclimate believed to have persisted since the late Tertiary period. These findings are part of ongoing research on the behavioural genetics of L. whitmani sensu lato aimed at understanding the evolution and maintenance of peri-domestic transmission of human cutaneous leishmaniasis.

A major assumption of the high-dose/refuge strategy proposed for insect resistance management strategies for transgenic crop plants that express toxins from Bacillus thuringiensis is that resistance traits that evolve in pest species will be recessive. The inheritance of Cry1F resistance and larval survival on commercially available Cry1F corn hybrids were determined in a laboratory-selected strain of European corn borer, Ostrinia nubilalis (Hübner), displaying more than 3000-fold resistance to Cry1F. Concentration-response bioassays of reciprocal parental crosses indicated that the resistance is autosomal and recessive. Bioassays of the backcross of the F1 generation with the selected strain were consistent with the hypothesis that a single locus, or a set of tightly linked loci, is responsible for the resistance. Greenhouse experiments with Cry1F-expressing corn hybrids indicated that some resistant larvae survived the high dose of toxin delivered by Cry1F-expressing plants although F1 progeny of susceptible by resistant crosses had fitness close to zero. These results provide the first direct evidence that the high dose/refuge strategy currently in place to manage resistance in Cry1F-expressing corn is appropriate.

The field of ecological immunology currently relies on using a number of immune effectors or markers. These markers are usually used to infer ecological trade-offs (via conflicts in resource allocation), though physiological nature of these markers remains elusive. Here, we review markers frequently used in insect evolutionary ecology research: cuticle darkening, haemocyte density, nodule/capsule formation, phagocytosis and encapsulation/melanization via use of nylon filaments and beads, phenoloxidase activity, nitric oxide production, lysozyme and antimicrobial peptide production. We also provide physiologically based information that may shed light on the probable trade-offs inferred when these markers are used. In addition, we provide a number of methodological suggestions to improve immune marker assessment.

The insect growth regulator buprofezin was tested using a leaf-dip assay on immatures of Bemisia tabaci (Gennadius). The method was robust and repeatable, and baseline data were calculated for a laboratory strain and a number of field collections from Pakistan where the insecticide has not been used. A baseline LC50 of 0.53 ppm buprofezin was defined and compared to other field collections. Populations known or suspected to have been intensively selected with buprofezin showed substantial tolerance to the insecticide at both the LC50 and at specific diagnostic doses, with the highest resistance factor of 47 fold in a population from the Netherlands. Reasons for the variation between populations, biotypes and geographical areas are discussed and the dangers of human-assisted movement of resistance genes are highlighted.

A sandwich enzyme-linked immunosorbent assay (ELISA) test was developed to detect blood-meals in insects and identify the host fed on. The test proved both sensitive and specific. Very small quantities of fresh blood (about 0·02 μl) can be detected; in practice, this enables blood in mosquitoes which are about three-quarters gravid to be identified. In trials in both Zambia and Britain, positive reactions were easily identified visually; consequently, this enabled the ELISA technique to be used as a routine field test. In addition to those of mosquitoes, blood-meals of a few Culicoides species were also successfully identified.

Termites were sampled using randomized soil pits in 64 cropping plots, each 25 x 25 m, forming an experimental agrisilvicultural system in both a 6- and an 18-year-old Terminalia ivorensis plantation, in which canopy cover, crop, cropping system and land preparation were the principal treatment variables. The treatments were established in April 1995 and sampling was carried out in November 1995, February 1996 and July 1996. A total of 82 termite species were found, of which 67 were soil-feeders. Overall termite abundance and the abundance of soil-feeders increased between November 1995 and July 1996, reaching a mean of nearly 6000 m-2. Pooling termite data from these sampling dates, in the old plantation, the high canopy cover treatment (192 stems ha-1) had a greater abundance of termites, compared with the low canopy cover treatment (64 stems ha-1) and this effect was independent of crop type (plantain or cocoyam), cropping system (single stands or mixed crops) and land preparation (mulch retained or burned, plantain only). The young tree plantation (same tree densities as in the old plantation) showed no significant difference in termite abundance between high and low canopy (levels of tree foliage) densities, though the high canopy sheltered a greater number of termites. Analysis of covariance showed that crop yield (both plantain and cocoyam) was not directly linked to the abundance of all termite populations, but that the cocoyam yield was positively correlated with the abundance of soil-feeding termites (the majority in the assemblage) in the young plantation. This may be due to the beneficial conditioning of soil resulting from the foraging and construction activities of soil-feeders.

A series of host-transfer trials using both laboratory-cultured and field-collected individuals of the aphid parasitoids Aphidius ervi Haliday and A. rhopalosiphi De Stefani Perez were done in order to clarify inconsistent results from several previous studies. A. ervi cultured on Acyrthosiphon pisum (Harris) produced very few mummies when confined with Microlophium carnosum (Buckton), whereas those cultured on M. carnosum produced as many mummies on A. pisum as they did on their original host. Mummy production was correlated with the attack rate of adult parasitoids on potential hosts. The production of mummies on M. carnosum by parasitoids reared on A. pisum was often greatly improved if their male parent had been reared on M. carnosum, suggesting that genotype strongly influences host preference. Aphidius rhopalosiphi from laboratory cultures produced significantly more mummies on Metopolophium dirhodum (Walker) than on Sitobion avenae (F.) regardless of their original host, but this preference was not shown by parasitoids from field populations. It is concluded that inadvertent selection occurs in laboratory cultures of aphid parasitoids as a result of low founder numbers, genetic drift and genetic bottlenecks and that this can strongly influence experimental results in biology and behaviour studies, which has important implications for biological control workers.

The dynamics of Bemisia tabaci (Gennadius) were followed during two years in treated and untreated cotton fields in three locations in Israel. Two parasite species, Encarsia lutea (Masi) and Eretmocerus mundus Merc., were the only important natural enemies, but percentage parasitism did not rise with increase in the host population. The whiteflies reached peak populations at the end of the summer. Their distribution upon the plants was not uniform, rather, they tended to concentrate on a few leaves. The leaf bearing the maximal population was the sixth or seventh until mid-July. From then on, its location was variable according to the growth pattern of the foliage. Insecticide treatments, in particular with aldicarb, resulted in depression of both whitefly and parasite populations, but neither was exterminated.

Five capture-recapture experiments with three species of the group of Anopheles punctulatus Dönitz were undertaken in four villages in Madang Province, Papua New Guinea. Females were collected in landing catches, blood-fed, marked with fluorescent powder according to time and location of capture, and released. Recaptures took place for 4–13 nights after release. A proportion of the recaptured mosquitoes was dissected for evidence of recent oviposition and gonotrophic age determination. Two models were developed to test a number of the assumptions that underlie the analysis of capture-recapture data from mosquitoes. Species abundance and numbers collected varied within and between villages, but marked mosquitoes dispersed at random within the mosquito population. No heterogeneity was found between indoor and outdoor biters of any of the three species. Survival rates were similar in all species. Significant differences were found in the duration of the oviposition cycle between species and village. This was 2·7–3·7 days for A. punctulatus, 2·4–3·2 days for A. koliensis Owen and 2·1–3·0 days for A. farauti Laveran. No differences were found in the duration of the oviposition cycle of nulliparous and parous females of A. farauti. Thus temporary pool breeders had a longer cycle than permanent pool breeders. This tended to be due to a delay in returning to feed rather than a delay in oviposition. It is concluded that differences between local environments exert a greater influence on the duration of the oviposition cycle than do species specific differences.