The efficacy of different aqueous dilutions of crude seed extract of Millettia ferruginea (Hochst.) Baker (1, 3, 5 and 10%) was evaluated under field conditions in terms of the level of damage and yield loss of maize caused by the maize stemborer Busseola fusca (Fuller) in Hawassa, southern Ethiopia. The insecticide lambda-cyhalothrin 5EC, applied at a rate of 16 g active ingredient/hectare, was used as the reference product. The experiment was carried out in a randomized complete block design with four replications. The maize variety A511 was planted in individual plots of 60 m2. Data on stand count, leaf infestation, bored stem and dead heart were collected weekly. Plots sprayed with the 5% concentration of Millettia showed low levels of damage (9–11% leaf infestation, 0.4% dead heart, 14–17% bored stem and < 0.2% bored ear), compared with plots sprayed with lambda-cyhalothrin. The treatments with 1 and 3% concentrations of Millettia were inferior to those with lambda-cyhalothrin and 5 and 10% concentrations of Millettia. In contrast, the treatment with the 10% concentration of Millettia led to the death of plants, thereby lowering the yield. About 80% of the total length of individual maize stalks from the untreated plots was internally tunnelled by the feeding larvae, while the internal stem tunnelling was low ( < 7%) in plants treated with Millettia at concentrations of 3, 5 and 10%. Among the treatments with Millettia, higher yields (37–48 decitonnes/hectare) were obtained from maize plots treated with 5% concentration. The use of the aqueous crude seed extract of M. ferruginea at a concentration of 5% applied two to three times is recommended for the control of B. fusca in maize.

The human body louse aggregates on filter paper impregnated with an aqueous extract of louse faeces. Chemical analysis of the faeces revealed the presence of haemoglobin, xanthine, hypoxanthine, uric acid and ammonium salts. Of all these compounds, only ammonium salts caused marked aggregation of lice. Excretory products of other insects and ticks also failed to induce aggregation. Total faecal material was more attractive than ammonium, and led to greater aggregation of females than of males. Antennectomized lice reacted neither to faeces extract nor to ammonium carbonate solution.

Vector-borne diseases such as malaria, lymphatic filariases, schistosomiasis, leishmaniasis, onchocerciasis, trypanosomiasis, dengue and dengue haemorrhagic fever (DHF), yellow fever and Japanese encephalitis, globally account for suffering amongst more than one billion people, mostly from the developing world. Geographical distribution and prevalence of these diseases have been discussed. In addition to the mortality caused by these diseases, millions of people lead a hopeless life and are socially unable to achieve self-realization and be economically productive, as a result of these diseases. Examples of such economic impact and the costs of these diseases and methods of control have been given. Economic benefits of control of some of these diseases have been discussed. These concepts are of utility when resource allocation for control of these diseases is under consideration.

In the present study, the synergistic effects of Beauveria bassiana (Bals.-Criv. Vuill.) (isolate Bb11) and Bacillus thuringiensis var. kurstaki (Berliner) with neem oil were evaluated in three agroecological zones in Bénin. Four bioinsecticide treatments (neem oil, neem oil and B. bassiana used separately for different target pests, neem oil mixed with B. bassiana and neem oil mixed with B. thuringiensis) were compared with a calendar-based treatment using synthetic insecticides and a control without insecticides. The bioinsecticide treatments were less effective than the calendar-based treatment at controlling cotton pests. There was no difference in yields and the number of damaged bolls in plots under treatments with the four bioinsecticide formulations, suggesting an absence of synergy between neem oil and B. bassiana and neem oil and B. thuringiensis. The numbers of natural enemies in all the bioinsecticide treatment plots and the control plots were similar and higher than those in the calendar-based treatment plots. The highest yield and profitability were obtained with the calendar-based treatment. Screening the compatibility of plant-based products and biopesticides through bioassays is essential for a successful application of their combinations in any integrated pest management strategy.

The African rice gall midge (AfRGM) Orseolia oryzivora Harris and Gagné is an important insect pest of rice in Nigeria. Studies were conducted at Ogidiga (forest zone) and Edozhigi (southern Guinea savanna) in Nigeria, under rainfed lowland conditions during the 2006 and 2007 rainy seasons, on the population dynamics of AfRGM adults using light trap and random sampling of % tiller infestation (plant damage due to AfRGM) and % parasitism by Platygaster diplosisae Risbec and Aprostocetus procerae Risbec (parasitized larvae and pupae and parasitoid species present in dissected tillers). The results obtained showed that AfRGM populations were relatively low in June and July – the beginning of the 2006 and 2007 rainy seasons, respectively – and increased abruptly from September, reaching a peak in October at both locations. The increase was attributed to the rapid build-up of the pest populations at both locations. There were strong positive correlations between adult populations from light-trap catches and % tiller infestation, and between % tiller infestation and parasitism. The peak period of parasitism by P. diplosisae and A. procerae occurred towards the end of the rainy season in October, coinciding with high level of % tiller infestation. It is concluded that conservation of the parasitoids early in the cropping season (i.e. to improve their synchronization with the host) could become an effective management strategy against AfRGM.

Laboratory and field studies were undertaken to establish the efficacy of some selected botanicals in the control of the tea red spider mite, Oligonychus coffeae Nietner, a major pest of tea. Bioassays were performed to evaluate the dose-mortality response of adults and eggs of O. coffeae to aqueous plant extracts. The order of adulticidal toxicity based on LC50 and slope values was Sapindus mukorossi L. > Nyctanthes arbor-tristis L. > Phlogacanthus thyrsiformis Nees. The order of ovicidal activity was reversed and was P. thyrsiformis > N. arbor-tristis > S. mukorossi. In addition, different concentrations of the aqueous extract of these plants exhibited repellent properties against adult mites and also significantly decreased the deposition of eggs by the mites on treated tea leaf surfaces. In field conditions, the extracts significantly reduced O. coffeae populations compared to propargite, a synthetic acaricide. There was no phytotoxic effect and the quality of tea was not adversely affected by the treatments. Further, the plant extracts caused no mortality or decrease in the predation efficacy of the adults and fourth instar larvae of Stethorus aptus Kapur, a natural predator of O. coffeae. Using the procedure adopted in this study, tea growers can easily formulate these low-cost eco-friendly botanicals for O. coffeae management in tea plantations.

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 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.

One tactic of importation of natural enemies for biological control of stemborers and other pests is the use of parasite species that have had no previous association with the pest. This ‘novel association’ approach offers the possibility of using parasites that have proven effective against a stemborer species other than the target stemborer pest. Nevertheless, creation of a novel host-parasite association requires that the novel host be ecologically and physiologically equivalent to the ancestral host. Selecting natural enemies based on ecological and physiological equivalence offers the best possibility of temporal, behavioural, nutritional and immunological compatibility in the host-parasite interaction, and reduces the chances of failure with the imported parasite species.

In this study, the effect of the application of three powdery mildew fungicides, namely triadimenol, triadimefon and sulphur, on the African weaver ant (AWA), Oecophylla longinoda Latreille, was evaluated for two seasons in two cashew fields, one each in the Bagamoyo and Mkuranga districts, Coast region, Tanzania. The fungicides were applied at monthly intervals, and the dynamics of AWA were monitored monthly by counting the number of leaf nests per tree and trails on main branches. There were no significant differences among the treatments on AWA at different observation dates in terms of the number of leaf nests and colonization of AWA trails per tree in the two cashew fields studied. In August 2011, for example, the number of leaf nests before application ranged from 7.8 to 9.0 and 13.6 to 14.6 in Bagamoyo and Mkuranga, respectively, and after application, it ranged from 7.8 to 10.0 and 12.4 to 15.2 in Bagamoyo and Mkuranga, respectively. The three powdery mildew fungicides did not have detrimental effects on the abundance of AWA in cashew fields and can, therefore, be used together with AWA as important components of an integrated pest and disease management programme for cashew crops in Tanzania.

Host preference studies were conducted on Trichogramma sp. nr. mwanzai at 25 ± 2°C, 40–60% r. h. In the laboratory, using eggs of C. partellus, B. fusca, E. saccharina, S. cerealella and B. mori in choice and no-choice tests. Adults emerged within 9–10 days; ca. 70% parasitoids of both sexes emerged and mated between 0800–1000 hr, with a peak at 0800 hr. There was no significant difference (P < 0.05) between the number of progeny per female from eggs of C. partellus (33.9 ± 9.2), B. fusca (30.1 ± 4.5) and S. cerealella (30.9 ± 9.9) in no-choice tests, but progeny production was significantly less from E. saccharina and no parasitoid emerged from B. mori. In host age selection tests on C. partellus, there was no significant difference (P < 0.05) between the number of offspring per female from eggs of age groups 0–2 days; offspring of day 3 were significantly less, and no parasitoid emerged from day 4 eggs. Up to 4 (mean, 1.9 ± 0.6) adults emerged from a single egg of C. partellus. Since mass rearing technology exists for C. partellus and is available at ICIPE, it was concluded that day 0–2 eggs of this borer are more suitable for mass production of T. sp. nr. mwanzai.

The effectiveness of maize (Zea mays L.) planted at different times in a maize–cucumber intercrop to reduce the density of cucumber insect pests was investigated in 2007 and 2008. The cucumber varieties Marketmore and Hybrid F1 were established from seed as a monocrop or intercropped with maize, and with maize established 2 weeks before cucumber (2WBC), the same day with cucumber (SDC) or 2 weeks after cucumber (2WAC). Irrespective of the cucumber variety, there was a significant reduction (over 50%) in the density of insect pests in the cucumber–maize intercrop compared with cucumber alone. Similarly, in both years, fruit damage was significantly lower (about 50%) in the intercropped cucumber, particularly at 2WBC and SDC, compared with cucumber alone. Cucumber fruit yield was significantly higher at SDC but significantly lower at 2WBC relative to the other times. In both years, a relatively higher yield for cucumber was obtained at SDC than at 2WBC and 2WAC. Therefore, a significant control of cucumber insect pests and a higher cucumber yield were obtained when cucumber and maize were planted on the same day.

It is known that in citrus orchards, the citrus psyllid Trioza erytreae (Homoptera: Triozidae) preferentially chooses certain varieties for egg laying, feeding and larval development. However, the selection mechanism in citrus nurseries is poorly understood. The aim of the present work was to study in the nursery, the behaviour of T. erytreae with respect to choice of egg laying and feeding sites in three species of citrus, namely Villafranca lemon, Mexican lime and Fremont mandarin. One hundred young plants of each were exposed to the citrus psyllid on the fourth month after germination, and psyllids and pit galls counted every month. The impact of the psyllid's damage on citrus was also assessed. Adults of T. erytreae were highly attracted to the young citrus plants three weeks after the germination of seeds. The average number of adults, eggs and larvae of T. erytreae by plant varied with the particular citrus plant: on young plants, adult, larval and egg populations were highest on lime. Four months later, 100 % of lime, 97% of lemon and 76 % of mandarin plants were attacked by T. erytreae. Those plants attacked shortly after germination were stunted and their leaves greatly deformed. In the absence of pest management in the citrus nursery, citrus psylla can cause the loss of up to 91 % of young plants.

Coptotermes heimi (Wasmann) is a termite widely present throughout Pakistan and causes detrimental effects in standing trees. In this study, the feeding preferences of C. heimi for 18 different wood species were determined through choice and no-choice trials under laboratory and field conditions. In no-choice laboratory trials, different combinations of wood blocks were used to determine wood consumption by C. heimi. Weight loss, consumption/individual and survival rate were evaluated. Populus euramericana was found to be the most susceptible wood species and Syzygium cumini the most resistant one. Nine different wood combinations were used under choice laboratory conditions; maximum feeding was recorded in P. euramericana and Pinus roxburghii (50.8–24.5 mg). However, minimum feeding was recorded in S. cumini (2 mg) and Tectona grandis (14.9 mg). Under no-choice field conditions, minimum feeding was recorded in S. cumini (9.5 mg) and maximum feeding in P. euramericana (60.5 mg). Under choice field conditions, maximum (58 mg) feeding was recorded in P. euramericana and minimum feeding in S. cumini. Feeding preferences in descending order based on wood consumption as a quantitative parameter documented were as follows: P. euramericana>Ailanthus excelsa>Azadirachta indica>P. roxburghii>Butea monosperma>Morus alba>Bauhinia variegata>Albizia lebbeck>Dalbergia sissoo>Heterophragma adenophyllum>Erythrina suberosa>Cassia fistula>T. grandis>Mangifera indica>Eucalyptus camaldulensis>Jacaranda mimosifolia>Bambusa bamboo>S. cumini.

Use of plant derivatives for insect pest control was common in the tropics before the advent of synthetic pesticides. Plants such as neem, Azadirachta indica A. Juss, chinaberry, Melia azedarach L., and Warburgia spp., have been known for insect repellent and antifeedant properties in addition to other plants possessing insecticidal and growth regulating properties. Practical usefulness of antifeedants derived from plants for management of insect pests in selected field crops and stored grains is discussed. These products would, however, require some definitions of quality control and standardization of biological properties for large-scale use.

The progress of the South African Sugar Association Experiment Station's 15-year-old biological control programme against Eldana saccharina Walker is reviewed. Two approaches at controlling this borer, a ‘new association’ and a ‘modified’ classical biological approach are summarised. Constraints identified as limiting the successful establishment of 10 egg, 12 larval and 2 pupal ‘new association’ parasitoids include host incompatibility, climatic incompatibility, poor ecological and biological life history knowledge, incorrect parasitoid searching ability and hyperparasitic tendencies. The 3 egg and 7 larval ‘modified’ classical biocontrol parasitoids which could be reared in the laboratory had constraints such as parasitising ability, different host habitat, differing host behaviours in different habitats and initial host identification difficulties to overcome. Difficulties encountered in this biological control programme against an indigenous pest insect show that biological control is not easy. Knowledge of constraints identified during this programme will hopefully be of use to others embarking on similar projects.

Laboratory studies were conducted to assess the toxicity and growth-inhibitory activity against Aedes aegypti larvae, of the crude acetone extracts of Polygonum senegalense (Meissn.) leaves, its flavonoid component 2',6'-dihydroxy-4'-methoxydihydrochalcone and the internal tissue flavanol quercetin. The first two showed significantly high insecticidal and growth-inhibitory activity even at low concentrations, whereas quercetin was toxic only at concentrations above 7μg/ml.

Adult pale morphs of an aphidophagous lady beetle, Propylea dissecta (Mulsant) (Coleoptera: Coccinellidae), were reared on a non-insect diet for periods ranging from 0 to 30 days after eclosion. The prey-deprived females, when provided with the cowpea aphid, Aphis craccivora Koch (Homoptera: Aphididae), laid fertile eggs, indicating that they had retained their reproductive potential. The oviposition period, post-oviposition period, fecundity, viability of eggs and longevity of females decreased significantly, whereas the pre-oviposition period and developmental period of progeny increased significantly with an increase in the duration of prey deprivation. There was no significant effect on the mean reproductive rate (16.14 ± 0.53 to 18.03 ± 0.67 eggs per day) at various prey deprivation levels, although the reproductive output and oviposition duration decreased. These findings indicate that lady beetle females can withstand the stress of prey non-availability, by switching to alternative food sources and reproducing when essential prey becomes available again.

An inventory of arthropods was carried out at locations in the desert area of Touggourt, southeast Algeria. Samples were collected from two diverse habitats, a palm grove (agricultural habitat) and dunes (natural habitat). Using the Barber pitfall trap, 1100 specimens, divided into four classes, 15 orders, 44 families and 99 species were obtained. In the palm grove, 660 arthropods were trapped, belonging to four classes and 12 orders. Of these four classes, Insecta dominated followed by Crustacea, Arachnida and Entognata. Insecta accounted for 59.49% of the total capture and was dominated by two orders: Hymenoptera (41.81%) and Amphipoda (34.55%). In the Hymenoptera, Cataglyphis sp. was the most abundant (38.2%), followed by Pheidole pallidula (2.3%). In the dunes, 440 individuals were trapped. Insecta was the most abundant (90.69%), and Crustacea and Arachnida were scarce. Of the dominance by insects, Hymenoptera was most abundant (68.15%), and within that order, Cataglyphis bombycina (35.5%) was the most abundant followed by Monomorium subopacum (8.9%). In the palm grove, 42 species were recorded, compared to 57 in the dunes. The Shannon–Weaver index and equitability varied in both stations. In the palm grove, the diversity was 2.6, and the equitability was 0.5. By contrast in the dunes, the diversity was equal to 4 and the Equitability equal to 0.7. The differences in vegetation between the two sites reflect the differences in species diversity.

Little is known about the efficacy of sampling methods for monitoring bee communities in agricultural landscapes in sub-Saharan Africa, in general, and in Uganda, in particular. To provide baseline information on the effectiveness of different sampling methods, 26 sites with varying landscape characteristics were sampled in 2006 in agricultural landscapes in Uganda. Bees were sampled using line transect count, coloured pan trap and hand net methods. In total, 80,883 bee individuals were collected. Totals of 59, 314 and 559 bee species were recorded in transect counts, pan traps and hand nets, respectively. Thus hand nets captured the most species overall. There were few species that overlapped across the three sampling methods. Wild bees were significantly more abundant in yellow pan traps than in blue or white ones. In contrast, bee species richness was significantly higher in blue pan traps than in white or yellow pan traps. Overall, pan-trapping was found to be a complementary method to hand-netting for monitoring bee communities in Uganda.