The stabling of horses at night reportedly offers protection from African horse sickness and the most significant vector of the disease, Culicoides imicolaKieffer, has been shown to be exophilic. In certain high-lying regions of South Africa, however, C. bolitinos Meiswinkel, may be the major vector of the disease but its entry behaviour into stables is unknown. Accordingly, in the eastern Free State province of South Africa, light trap catches of C. bolitinos inside stables and outside, were compared. Two horse-baited stables, one traditional, and one modern, were used and combinations of stable (old/new), ceiling fans (on/off) and accessibility to Culicoides (stable doors open/closed or windows gauzed/ungauzed) were investigated as treatments. A total of 111,452 Culicoides of 26 species was collected on 60 trap nights; C. bolitinos was dominant (89.1% overall) with C. imicola second in abundance (2.9%). Outside catches were greater on warmer, drier, evenings but were suppressed by high wind speeds. Catches of C. imicola inside stables with doors open, or with windows ungauzed, were less than the numbers captured outside. In contrast, more C. bolitinos were caught in open stables than outside, i.e. open structures may protect horses from the exophilic C. imicola, but may increase attack rates from the endophilic C. bolitinos. The closing of doors and the gauzing of windows, however, led to a 14-fold reduction in numbers of C. bolitinos and C. imicola entering stables. A well-gauzed ‘traditional’ stable was as effective as a closed ‘modern’stable. Ceiling fans had no suppressant effect.

Field experiments were performed in artificial ponds to evaluate how the density of predatory diving beetles (Dytiscidae) would affect the population levels of mosquito larvae (Culicidae). Mosquitoes colonizing the ponds were predominantly species of the genus Culex. In 2000, most of the dytiscids colonizing the ponds were small (Hydroporus spp.), and these predators had no impact on the size of larval mosquito populations, not even in ponds with added dytiscids. In 2001, larger beetles (Ilybius, Rhantus, and Agabus spp.) were more common, and there were significantly fewer mosquito larvae in ponds with the highest numbers of dytiscids. There was a negative correlation between numbers of diving beetles in the ponds and the mean body length of mosquito larvae. In neither year could dytiscid densities be maintained above a certain level owing to emigration. In laboratory tests, there were marked differences between three common dytiscid species in regard to preferences for Daphnia and Culex species as prey: Colymbetes paykulli Erichson chose mosquito larvae more often, whereas both Ilybius ater (De Geer) and I. fuliginosus (Fabricius) preferred Daphnia spp. All of the tested dytiscids consumed large numbers of prey. Since some dytiscid species can efficiently decrease populations of mosquito larvae, they are probably important in the natural control of these dipterans.

The numbers of insects colonizing the dung of cattle injected with the anthelmintics ivermectin or moxidectin were compared with the colonization of the dung from control animals given no treatment, in a blind field trial. Dung was collected 2, 7, 14, and 21 days after dosing and set out in a randomized grid of standard 2 kg pats. Pats were retrieved from each of the three groups group after 7, 14, 21 and 42 days in the field for analysis of insect fauna. There were no significant differences in the number of adult Aphodius spp. (Coleoptera: Scarabaeidae) found in the dung from the three treatment groups with either time of exposure in the field or time after treatment, showing that adult beetles were attracted to all pats equally. However, dung from animals treated with ivermectin prevented the development of larval Aphodius spp. for at least 7 days after treatment. In contrast, the dung from animals treated with moxidectin supported the development of Aphodius spp. at all stages after dosing, as did dung from control animals. There were no significant differences in the number of cyclorrhaphous Diptera larvae in dung from control or moxidectin-treated animals. In contrast, such larvae were largely absent from the dung collected from ivermectin-treated cattle for up to 14 days after dosing. The results show that moxidectin is less toxic to dung-inhabiting insects than ivermectin following standard injection treatment. The results are discussed in relation to the effects of anthelmintics on non-target pastureland insects.

In the course of an experiment in malaria control in an inland region of Kenya and Tanganyika, by the use of house spraying with dieldrin, routine catches were maintained of mosquitos resting in artificial outdoor shelters. During the 18 months of the pre-spraying period, catches in the South Pare district of Tanganyika mainly consisted of the principal vectors, Anopheles gambiae Giles and A. funestus Giles, together with small numbers of A. rivulorum Leeson.

During the three years following the spraying, A. funestus disappeared almost completely from the catches, while A. rivulorum showed an increase of about seven times above its former level.

The preparation and use of a simple, durable silicone membrane for feeding females of Glossina morsitans Westw. are described. Mean fecundity and mean pupal weight were nearly as good on the silicone membrane as on agar/Parafilm or rabbit ears, and survival of females after 108 days was 46·7%, as against 4·4% and 24·7%, respectively.

Arabica coffee was sampled from two sites in the central highlands of Kenya (Rurima, Ruiru) and one site on the western side of the Rift Valley (Koru). Three species of ceratitidine Tephritidae, Ceratitis capitata (Wiedemann), C. rosaKarsch and Trirhithrum coffeae Bezzi, were reared from sites in the central highlands, and an additional species, C. anonae Graham, was recovered from the western-most site. Ten species of parasitic Hymenoptera were reared from these tephritids. The parasitoid assemblage was dominated by koinobionts. Eight of the species are koinobiont endoparasitoids, but only one idiobiont larval ectoparasitoid was reared, and only one idiobiont pupal endoparasitoid. The effects of sampling bias on determination of parasitoid assemblage size associated with concealed hosts are discussed. The potential for use of these parasitoids in biological control is also discussed. Most of the parasitoid species recovered during this study are capable of developing on C. capitata, while several also attack C. rosa. Both flies are notorious pests of tropical and subtropical fruits.

One–dimensional slab polyacrylamide gel electrophoretic techniques, staining systems and isoenzyme banding patterns for 14 soluble enzymes separated from crude homogenates of individuals of six species of cereal aphids (Sitobion avenae (F.), S. fragariae (Wlk.), Metopolophium dirhodum (Wlk.), M. festucae (Theo.), Rhopalosiphum padi (L.) and R. maidis (Fitch)) are described. The value of the techniques and banding patterns to taxonomic and population genetic studies of these and other aphid species are briefly discussed. With the six species, it was possible to separate the different genera as well as individual species within genera. The enzymes found to be most useful for inter–generic and/or -specific separations were adenylate kinase (AK), esterase (EST), glucose-6-phosphate dehydrogenase (G-6-PDH), hexokinase (HK), malate dehydrogenase (MDH), peptidase (PEP), phosphatase (PHOS), phosphoglucomutase (PMG), 6-phosphogluconate dehydrogenase (6-PGD) and sorbitol dehydrogenase (SORDH), whilst glutamate oxaloacetate transaminase (GOT), α-glycerophosphate dehydrogenase (α-GPD), malic enzyme (ME) and peroxidase (POD) were of relatively little taxonomic use. There were no banding pattern differences between the various morphs of S. avenae (first to fourth-instar nymphs, apterous and alate adults using the 14 enzymes.

The soybean pod gall midge is an important pest of soybean in Japan and is known to occur also in Indonesia and China. This gall midge is described from Japan as Asphondylia yushimaisp. n. and is clearly distinguished from its congeners by the arrangement of the lower frontal horns of the pupa and the sequence of the mtDNA COI region. It is concluded that Prunus zippeliana Miquel is a winter host of the soybean pod gall midge since haplotypes of the soybean pod gall midge coincide with those of the Prunus fruit gall midge that produces fruit galls on P. zippeliana. In addition, phenological and distributional information on the two gall midges and on their host plants supports the identification of the winter host. In Japan, the soybean pod gall midge overwinters as a first instar in the fruit galls on P. zippeliana and emerges as an adult from the galls in May. In summer and autumn, the soybean pod gall midge has two or more generations in the pods of soybean, Glycine max (L.) Merrill or wild fabaceous and caesalpiniaceous plants. Thus host alternation by A. yushimai is confirmed. This is the second finding of host alternation by a species of Asphondylia, the first instance being that of Asphondylia gennadii (Marchal) in Cyprus.

New Zealand is currently the only major fruit producing country in the world that is free of economically important fruit flies. As part of the effort to maintain this status, there is a need to supplement quarantine decision-making procedures with a means of rapidly identifying immature life stage infestations to the species level. Here we describe a molecular method that achieves this, using simple restriction patterns of ribosomal DNA (rDNA) as diagnostic markers. The 18S and 18S plus internal transcribed spacer (ITS) regions were amplified from larval DNA by the polymerase chain reaction (PCR). Nineteen species, spanning four genera (including five subgenera of Bactrocera) were analysed. Restriction analysis of the 18S PCR product provided poor resolution, even at the generic level. Digestion of the 18S + ITS PCR product, however, generated thirteen diagnostic haplotypes as defined by the composite restriction patterns from RsaI, Sau3a HaeIII and AluI. No variation was detected at these restriction sites within or between populations. Twenty two restriction enzymes have been screened, but diagnostic RFLPs have yet to been found for six out of the ten Bactrocera (Bactrocera) species; B. passiflorae (Froggatt) cannot be distinguished from B. facialis (Coquillet), nor B. kirki (Froggatt) from B. trilineola (Froggatt) or B. neohumeralis (Hardy) from B. tryoni (Froggatt). Geographic origin could assist in distinguishing the first four species, but the latter pair are very closely related with overlapping origins, hosts and adult morphology. All six species, however, are considered high risk with respect to their likely establishment in New Zealand. Therefore diagnosis based on this molecular technique would support the same quarantine decision. We consider this method could be useful as a diagnostic technique and discuss directions for further development.

The diamond-back moth, Plutella maculipennis, and Crocidolomia binotalis are the main pests of cabbage in Indonesia. Until 1951, good control was obtained with DDT sprays and dusts, but in that year growers near Lembang (Bandung) obtained poor results with DDT against P. maculipennis as compared with previous years. Investigations were started in Lembang, and also in Patjet (on Mt. Gedeh) where no difficulties had arisen. In laboratory experiments, a marked difference in susceptibility to DDT between a Lembang and a Patjet strain of P. maculipennis was demonstrated.

In field tests near Patjet with DDT, BHC and toxaphene, DDT gave satisfactory control and was better than the other two. At Lembang, however, where these three materials were again tested, but with derris and pyrethrum also, toxaphene was the most effective, followed by derris and BHC, while DDT, and also pyrethrum, gave almost no control.

For the time being, toxaphene and derris are recommended, the former during the growing season and the latter subsequently, but it is feared that resistance to toxaphene will develop. It may become necessary to resort to cultural and biological measures.

For some years after the intensive study of mosquitos began in tropical countries, surprisingly little interest was taken in the European species, particularly those of Northern Europe. Ficalbi had published his monographic revision in 1896–99, but from then until 1914 very little further had been done; the adults were assumed to be more or less known, though very few of the larvae had been described. Since 1914, however, a great deal of work has been done all over Europe, bionomic as well as systematic, and considerable advances have been made in every branch of our knowledge of these insects.

The life history of Frankliniella occidentalis (Pergande) was studied at six different temperatures on English cucumbers, cv. Pepinex. Life tables constructed indicate that the highest population growth rate (rm) and net reproduction rate (R0) occur at 30°C and the lowest at 15°C, where the population remains nearly stable. Generation time (T) was the shortest at 30°C and increased as temperature decreased. At 30°C oviposition increased, females matured and reproduced earlier and the time specific fecundity (mx) was higher than at lower temperatures. Adult longevity was shortest at 30°C and longest at 15°C. The threshold value for development was determined as 9.4°C. Average duration of each developmental stage and the sex ratio at six different temperatures are given.

Larvae of Aphidoletes Kieffer and Monobremia Kieffer feed exclusively as predators on aphids. The taxonomic status of these genera and their included species is reviewed and new generic and specific synonymies are given. A. aphidimyza (Rondani), A. urticariae (Kieffer), A. abietis (Kieffer), A. thompsoni Möhn and M. subterranea (Kieffer) are accepted as good species and a neotype is designated for A. urticariae. Diagnostic characters of these species are indicated and characters of the male genitalia, female wings and larval skins are illustrated. Published information on their biology, particularly of the commonest species A. aphidimyza, is summarized and includes details of host ranges and geographical distribution. Lestodiplosis grassator (Fyles), L. pini Barnes, Trilobia aphidisuga Del Guercio, Uncinulella eriosomiperda Del Guercio, Trilobiella siphae Del Guercio and Adelgimyza strobilobii Del Guercio probably prey on aphids but have not been recognized since they were originally described. Comparative assessments of field populations of Aphidoletes by examination of aphid colonies in the field, by incubation of samples in polythene bags and by laboratory examination of samples fixed in 70% ethyl alcohol showed that only the last gives accurate counts of eggs and larvae. Counts of aphids, Aphidoletes, Syrphids, Coccinellids and Anthocorids in 35 samples taken from aphid colonies occurring at Wisley in 1970–72 are tabulated, together with seven samples from other localities. Aphidoletes (mainly A. aphidimyza) was numerically the dominant predator in all three years at Wisley and was about ten times more numerous on wild plants than on cultivated plants.

The percentage infection of secondary symbionts (SS) (Wolbachia, Arsenophonus, Rickettsia, Hamiltonella, Fritschea and Cardinium) in the exotic Bemisia tabaci (Genn.) invaders, commonly known as biotypes B and Q from China, were determined by PCR. In total, 373 biotype B and 1830 biotype Q individuals were screened for the presence of SS. Biotype B was more abundant than biotype Q from 2005 to 2006, and biotype Q was more abundant from 2007 to 2009. Each of the SS, with the exception of Fritschea, was detected in both biotypes B and Q; Fritschea was found in none of the samples examined. For biotype B, the percentage infection of Hamiltonella was the highest (92.0%) followed by Rickettsia (70.2%). For biotype Q, the percentage infection of Hamiltonella was again the highest (73.3%). Arsenophonus was the least common of the SS observed in both biotypes B and Q. The percentage infection of Wolbachia, Rickettsia and Hamiltonella in biotype B was each significantly higher than in biotype Q, whereas the percentage infection of Cardinium in biotype B was significantly lower than in biotype Q. The percentage infection of SS in biotypes B and Q varied from year to year over the period 2005–2009. Furthermore, within biotype Q, two distinct subgroups were identified which differ from each other in terms of their SS complement. We discuss these results in the light of the potentially influential factors and roles of the SS.

Mononychellus tanajoa (Bondar), a spider mite new to Africa, was discovered on cassava in Uganda in 1971. This exotic mite of Neotropical origin has since spread to 27 countries, causing an estimated 13–80% reduction in cassava yield. The history of its introduction and spread in Africa is reported, and present knowledge on the taxonomy, biology, ecology and pest status of the mite, and the evolution of strategies to control it are reviewed. While attempts have been made to control M. tanajoa, it remains a serious pest in most areas. The prospects for classical biological control as an appropriate control strategy are discussed.

Seed predation is an important component of seed mortality of weeds in agro-ecosystems, but the agronomic use and management of this natural weed suppression is hampered by a lack of insight in the underlying ecological processes. In this paper, we investigate whether and how spatial and temporal variation in activity-density of granivorous ground beetles (Coleoptera: Carabidae) results in a corresponding pattern of seed predation. Activity-density of carabids was measured by using pitfall traps in two organic winter wheat fields from March to July 2004. Predation of seeds (Capsella bursa-pastoris, Lamium amplexicaule, Poa annua and Stellaria media) was assessed using seed cards at the same sites and times. As measured by pitfall traps, carabids were the dominant group of insects that had access to the seed cards. In the field, predation of the four different species of seed was in the order: C. bursa-pastoris>P. annua>S. media>L. amplexicaule; and this order of preference was confirmed in the laboratory using the dominant species of carabid. On average, seed predation was higher in the field interior compared to the edge, whereas catches of carabids were highest near the edge. Weeks with elevated seed predation did not concur with high activity-density of carabids. Thus, patterns of spatial and temporal variation in seed predation were not matched by similar patterns in the abundance of granivorous carabid beetles. The lack of correspondence is ascribed to effects of confounding factors, such as weather, the background density of seeds, the composition of the carabid community, and the phenology and physiological state of the beetles. Our results show that differences in seed loss among weed species may be predicted from laboratory trials on preference. However, predator activity-density, as measured in pitfall traps, is an insufficient predictor of seed predation over time and space within a field.

Female Musca vetustissima Wlk. may be allocated to one of seventeen classes of development between emergence and the start of the fourth ovarian cycle, the criteria being the amount of pupal fat body, but chiefly the presence and size of the follicular relics (yellow bodies and beads in the ovaries) during successive ovarian cycles. The duration of these cycles was estimated under standard and differing environmental conditions. Withholding protein for up to two weeks merely delayed the first ovarian cycle, but longer deprivation caused reduced fertility. The initial phase of the first ovarian cycle was independent of protein feeding, but a protein feed was necessary to complete the cycle, and a further protein feed was needed to complete the second ovarian cycle. No development in the first cycle took place below 57°F, but between 58 and 78°F development was progressively faster. Unfertilised females developed and laid the first batch of eggs, but were unable to complete a second batch. Oviposition was delayed by lack of favourable sites, and after one week fertility was progressively reduced. It is shown that, because of these variables, valid estimates can be made only of the minimum age of female bushflies.

(1) Three insects, Tribolium confusum, Ephestia kuehniella and Dermestes vulpinus, have been grown at several humidities and the following factors have been determined: length of larval period; water content of food and of the freshly formed pupae; wet and dry weight of pupae and wet and dry weight of food consumed during larval development. The “net utilisation” of the food has been calculated as the ratio of dry weight of food eaten per larva to dry weight of pupa.

(2) At lower humidities more food is eaten to produce a given unit of body weight. The length of the larval period increases and the weight of the pupae decreases.

(3) More food is eaten at low humidities, because part of the food is utilised as water. As a consequence of this, the larva grows more slowly and its final size is smaller. It is shown for Dermestes at 30 per cent. and Ephestia at 1 per cent. R.H. that less than 32·9 and 7·6 per cent. of the water in the pupae can be derived from water ingested with the food.

The arthropod community associated with irrigated rice grown in five sites in Luzon Island, Philippines, was analysed using guild categories. Phytophages and predators were predominant in all sites. The phytophage species were mainly Homoptera and dominated by Nephotettix virescens (Distant), N. nigropictus (Stål) (Cicadellidae), and Nilaparvata lugens (Stål) and Sogatella furcifera (Horváth) (Delphacidae). Predators were mainly Heteroptera with Microvelia douglasi atrolineata Bergoth (Veliidae), Mesovelia vittigera (Horváth) (Mesoveliidae), and Cyrtorhinus lividipennis Reuter (Miridae) as the most abundant species. Spiders were the next dominant group with Pardosa pseudoannulata (Böesenberg & Strand) and three species of Tetragnatha the most common. Differences in species diversity between the sites were easily differentiated using diversity indices. The relative differences in arthropod abundance, species richness and diversity may be attributed to the median temperatures, cropping patterns, and diversity in crop stages and germplasm in the sites. Predator-Homoptera correlations were significant in all cases. High positive correlations were obtained for veliids, spiders and Cyrtorhinus lividipennis, in most sites.

Insect cytochrome P450 monooxygenases (P450s) play an important role in catalysis of many reactions leading to insecticides resistance. Our previous studies on transcriptome analysis of chlorantraniliprole-resistant development in the diamondback moth, Plutella xylostella revealed that up-regulation of cytochrome P450s are one of the main factors leading to the development of chlorantraniliprole resistance. Here, we report for the first time a novel cytochrome P450 gene CYP321E1, which belongs to the cytochrome P450 gene family CYP321. Real-time quantitative PCR (RT–qPCR) analyses indicated that CYP321E1 was expressed at all developmental stages of P. xylostella but was highest in the fourth-instar larvae; furthermore, the relatively high expression was observed in the midgut of the fourth-instar larvae, followed by fat bodies and epidermis. The expression of CYP321E1 in P. xylostella was differentially affected by three representative insecticides, including alphamethrin, abamectin and chlorantraniliprole. Among them, the exposure to chlorantraniliprole resulted in the largest transcript level of this cytochrome P450 gene. The findings suggested potential involvement of CYP321E1 in chlorantraniliprole resistance of P. xylostella. To assess the functional link of CYP321E1 to chlorantraniliprole resistance, RNA interference (RNAi)-mediated gene silencing by double stranded RNA (dsRNA) injecting was used. Results revealed that injection delivery of dsRNA can greatly reduce gene expression after 24 h. As a consequence of RNAi, a significant increment in mortality of larvae injected CYP321E1 dsRNA was observed after 24 h of exposure to chlorantraniliprole. These results strongly support our notion that this novel cytochrome P450 gene plays an important role in chlorantraniliprole detoxification in the diamondback moth and is partly responsible for its resistance.