Local West African strains of Sitophilus oryzae (L.) and Tribolium castaneum (Herbst) were placed in 200 g of wheat samples, one species after the other, during 6 weeks. The rate of infestation for S. oryzae was 6, 12, 24 or 48 pairs of adults, while it was fixed to 20 for T. castaneum. The generation of S. oryzae was killed by fumigation before T. castaneum infestation of the grain samples. The loss in dry weight and the frass production were recorded at the end of each rearing period of time for each species.

The dry matter loss caused by S. oryzae was highly correlated with the rate of adult infestation and measured as high as 600 mg per infesting pair of weevils. The frass production for both S. oryzae and T. castaneum was highly correlated with the rate of infestation by weevils only. For S. oryzae, the average frass production was about 60 mg per adult pair, while for T. castaneum it was variable from 27 to 44 mg per pair of the primary infestation level by the weevils.

The importance of these results is discussed in relation to standard loss assessment methods when there are several infesting species and particularly when there is a preponderance of secondary species over primary species.

The use of synthetic acaricides in tick control is increasingly becoming more expensive. As a result, a lot of Africa's resource-poor farmers are failing to dip their cattle regularly. Natural products offer these farmers a cheaper alternative to synthetic acaricides. There is indeed a great potential for the use of Africa's huge natural resources, the plants to develop sources of acaricides to reduce the cost of tick control being locally available and potentially being able to be produced and used by farmers themselves or by cottage industries. It is, however, necessary that research centres such as ICIPE encourage the development of systematic research on natural products in order to bring about the Tephrosia vogelii leaf extracts observed to be highly toxic to one-, two- and three-host ticks and cattle sprayed with the extract had a residual protection period of 10 days from re-infestation by ticks.

A headcage technique to screen for resistance to sorghum head bug, Eurystylus immaculatus Odh. (Hemiptera: Miridae) was standardized for use in West Africa. Panicles infested at the half-anthesis to complete-anthesis stage had greater population build-up and suffered maximum grain damage, loss in grain mass, grain hardness and seed germination. Panicles with higher grain damage also showed greater severity of grain mould incidence. Maximum population build-up and grain damage was recorded in panicles infested with 20 pairs of adults. Panicles infested with 30–40 pairs of bugs generally showed a decrease in population build-up, possibly because of crowding. Head bug numbers decreased with a decrease in panicle size, while the extent of grain damage increased. To screen for resistance to head bugs, data should be recorded both on head bug numbers and grain damage. Fifty nymphs (third to fourth instar) or 40 bugs collected at random can also be used in the headcage to screen for resistance to head bugs.

Insects exhibiting swarming habits in Lake Victoria include mainly the Chironomidae, the Chaoboridae and Povilla adusta (Ephemeroptera). Their early life cycles are spent in the lake as benthos and standard bathymetrie procedures were undertaken to estimate the standing crop biomass of the larvae in Murchison Bay. Povilla was principally a boring invertebrate preferring dried logs (113 g Povilla nymphs per kg of host plant material). Cyperus papyrus carried 5 g C. denudalas 2.5 g and Phragmites mauritanus 1.0 g of Povilla per kg of host plant material. Povilla also occurred in the benthos at 40 g/m2. The Chironomidae and Chaoboridae had a mean standing crop biomass of 80 g/m2 and 3 g/m2 respectively. Their total biomass for the bay was estimated at 16060 metric tonnes for the Chironomidae, 7920 m. t. for Povilla and 660 m. t. for the Chaoborids. Adult swarming habits of the lakefly were closely correlated with lunar phases and the adults were easily trapped at night using kerosene lamps. Biochemical tests of the nutrient value of lakefly showed high levels of protein content (62%), minerals (18%), a low fat content (3.9%) and low moisture content (9%). This makes the lakefly ideal as an additive in animal feeds and growth experiments with poultry and aquaculture fish are currently going on to test the suitability of lakefly as an ingredient in animal feeds.

Paper discusses five substantive issues affecting farmer participation (FP) in the development of integrated tick management (ITM). These are the concepts, methods, incentives for and constraints to farmer participation (FP), and finally, case study material illustrating how FP has contributed to the research and development of integrated tick management.

Eucalyptus oil vapour treatment provided to Dysdercus koenigii female individuals as virgin adults or during their fifth instar nymphal life led to a fall in the total protein content accompanied by a rise in the free amino acid titre of haemolymph and fat body. However, the level of total lipids in these two tissues under such condition varied in that a decrease and an increase were recorded in haemolymph and fat body respectively. In the ovary of this adult female, the amounts of total proteins and lipids were low, while the value for total free amino acids was high. The implications of all these findings are discussed chiefly in relation to transport, synthesis and degradation of biochemical constituents in the three tested tissues.

Feeding on Ricinus communis leaf treated with different concentrations (0.1, 0.3 and 0.5%) of ether extracts of Erithrina indica seed and Delonix regia flower against Ergolis merione, Porthesia scintillans and Spodoptera exigua resulted in high larval and pupal mortality. Food consumption, assimilation, conversion and fecundity decrease with increasing concentration. Larval mortality was 20 to 91 % and damage was decreased by 65% through the application of the highest concentration of each chemical.

The various methods of controlling tick infestation on livestock are reviewed, highlighting their strengths and weaknesses. A framework for developing an IPM approach including socioeconomic considerations for ticks control is proposed. Efforts at practising IPM on ticks are highlighted.

Various wood species used for granary or crib construction were tested for their susceptibility to Prostephanus truncatus (Horn), a new stored grain pest in Benin found in 1984. Ten of the widely used wood species were chosen after survey in infested zones. Wood samples were dried in the oven (60°, 72 hr). They were reduced to 20 cm length, with diameter 2.0–2.6 cm and moisture content varying from 11.1–12.7%, respectively. Wood densities ranged from 0.455–0.999 g/cm−3. Fifty adult insects (<7 days old) were released into the middle of a sample made up of the 10 wood species for free-choice assays and 20 insects per wood species in no-choice tests. Four replicates were set up for each category. After 45 days of exposure at a temperature of 20–35°C and 60–90% r.h., data related to number of Insects that had penetrated each wood, number of larvae, and length of tunnelling were assessed. From the overall data analysis, Elaeis guineensis Jacq. and Holarrhena floribunda (G. Don) appeared least susceptible. Tectona grandis L., Fagara xanthoxyloides Lam., Azadirachta indica A. Juss and Mallotus oppositifolius (Geisel). Mull. Arg. were the more susceptible wood species.

Nigeria livestock population is estimated at about 12.3 M cattle, 9 M sheep, 23 M goats, and 1 M pigs distributed nation-wide, but with over 90% in the savannah zones in the country. Ticks and tick-borne diseases are endemic although incidence rate varies with seasons and livestock concentration. Ixodid ticks of the genera Amblyomma, Boophilus, Hyalomma and Rhipicephalus are of the greatest economic importance in livestock production in Nigeria. Control measures have been based mainly on dipping and spraying with acaricides, although a lot of management problems have characterized the drive towards effective tick control.

There is as yet no research centre for ticks and tick-borne diseases in Nigeria. Much of the work being done is carried out at the Veterinary Faculties of five Nigerian universities at Nsukka, Ibadan, Zaria, Sokoto and Maiduguri. A proper epidemiological base line data is still needed in the formulation of effective control measures. Economic losses, attributable to ticks and tick-borne diseases in Nigeria run into several millions of Naira per annum.

An Integrated Pest Management (IPM) approach is considered a long term option for effective tick control in Nigeria.

The predacious mites Amblyseius gossipi El-Badry and A. swirskii Athias-Henroit developed, survived and reproduced successfully on several artificial diets. The best diet consisted of 1 g yeast, 1 g milk, 30 mg cystine, 30 mg proline, 30 mg arginine, 20 mg sucrose, 50 mg glucose, 30 mg streptomycin sulphate and droplets of sorbic acid. Mean eggs/female/day by the two predators was 0.54 and 0.30 when reared on the best diet compared to 1.21 and 0.40 when fed on a natural diet, respectively. Female longevity of A. swirskii was 84.3 days, nearly twice as long as that on a natural diet Eggs showed no abnormalities; larvae fed on diets had normal development, and adults were comparable in size to individuals reared on a natural diet.

Au Rwanda, on a identifié 45 espèces des tiques dont 5 d'entre-elles sont les plus répandues et les plus dangereuses. Ces tiques infestent le bétail qui lui paie un très lourd tribut suite aux effets du parasitisme et à la transmission des maladies graves telles que la théilériose, lababesiose, l'anaplasmose, les rickettsioses, etc. De nombreux efforts sont déployés depuis plus de 35 ans pour contrôler la population des tiques et pour prévenir et guérir les maladies transmises par ces vecteurs. L'insuffisance du budget et du personnel affecté à ce programme compromet les chances de succès des activités pourtant vitales pour l'économie de l'élevage. Il est impérieux de relancer le service national de lutte contre les tiques.

Detailed biology of the sorghum earhead bug, Calocoris angustatus Lethierry was studied at Dharwad, India during 1979–1981. Egg incubation and nymphal developmental period ranged from 5.6–11.0 and 10.0–17.0 days, respectively. The duration of first, second, third, fourth and fifth nymphal instars was 2.2 to 3.4, 2.3 to 3.0, 2.0 to 2.8, 2.0 to 3.0 and 2.0 to 2.7 days, respectively. The males lived for 8.9 to 17.6 days and females for 12.2 to 21.3 days. Fecundity varied from 57.7 to 267.1 eggs per female. Preoviposition, oviposition and post oviposition periods varied from 1.2 to 2.1, from 7.2 to 14.0 and from 5.0 to 15.8 days, respectively. All the developmental stages of the bug are described.