Field studies were done to elucidate the effectiveness of buffalo urine as a tsetse attractant under a variety of test conditions. When traps were baited with the test sample of urine placed in large-necked dispensers allowing evaporation of 2 to 2.9 ml/hr, they performed better than traps baited with similar samples placed in narrow-necked dispensers with evaporation rate of 0.2 to 0.4 ml/hr. Buffalo urine was compared with samples of cow urine: the catch size increased 1.8 times in traps with cow urine when compared to that of the control trap, whereas buffalo urine was 9.6 times more attractive than control. Acetone added to the test sample, even in very small quantity, boosted the effectiveness, increasing the catch size 2.8 times more. Urine samples that had stayed on the laboratory shelves for some weeks or months were more effective than freshly obtained ones.

Intrinsic toxicity of seven insecticides including bromophos, bromophos-ethyl and deltamethrin to the Indian hive bee Apis cerano indica is reported. Bromophos was safer than endosulfan, while deltamethrin was the most toxic.

The use of indigenous plant materials for the construction of biconical traps to control tsetse is described. Preliminary results from field trials indicated that traps made entirely from local materials performed almost as well as a standard design. It is intended to promote the construction and use of these traps on a community self-help basis in sleeping sickness areas of Uganda.

Desmodium tortuosum (Sw) DC (Papilionaceae) is a preferred wild host of Heliothis virescens (Fabricius) (Lepidoptera: Noctuidae) which is an important pest of cotton in Tolima, Colombia. From November 1976 until March 1979, cotton and D. tortuosum were compared and contrasted in the field as hosts of the pest. A very high infestation level of H. virescens in cotton in 1977 was preceded by an extremely low infestation level of the insect in D. tortuosum previous to the cotton-growing season. In 1978 and 1979 moderate infestation levels in cotton were preceded by moderately low infestation levels of H. virescens in D. tortuosum previous to the cotton growing season in both years.

Progressively less eggs were laid on cotton versus D. tortuosum as the cotton plants aged. Peak numbers of H. virescens occurred during the latter part of the cropping season and immediately after. A mean of 13% of first-instar larvae of H. virescens on D. tortuosum were found stuck by the glandular trichomes of the plant. On cotton significantly more eggs were found during the week of full moon than new moon or first quarter. Apparent sterility and pre-hatch mortality of eggs of H. virescens varied between 1–5 and 0 and 7%, respectively, for both hosts combined.

Egg parasitism by Trichogramma sp. (Hymenoptera: Trichogrammatidae) in cotton was 1.5% in 1977, presumably due to excess use of pesticides, and 23.5% in 1978 when pesticides were not used much. Parasitism of eggs on D. tortuosum by the same parasite averaged 1%; the glandular trichomes of D. tortuosum trapped and killed adult Trichogramma.

The fact that infestation levels of H. virescens in cotton were very high in the year that they were very low in D. tortuosum previous to the cotton-growing season, and moderate in cotton during 2 years that they were not as low previously in D. tortuosum suggests that the continued presence of the pest many aid its natural regulation, perhaps by providing a source of hosts to H. virescens specific parasites.

If relative levels of oviposition in cotton could be predicted by lunar cycles this would aid in planning control strategies, such as massive liberations of egg parasites and more intensive monitoring of infestation levels during predicted peak periods.

Males of the Triatominae, Panstrongylus megistus and Triatoma infestons, show a considerable difference concerning the time necessary for them to acquire the capacity for the first mating. P. megistus copulates from the eighth day of adult life, irrespective of whether or not it has been fed, while T. infestons copulates about 17 days after the imaginai moult and only after a blood-meal. These differences might be due to the secretory activity of T. infestons male accessory glands whose full development is reached only after two saturant blood-meals. If allatectomy is performed in male P. megistus soon after the imaginai moult, accumulation of secretion does not occur in 3 of the 4 accessory glands. Topical application of precocene II (200 μg/insect)a few days before or soon after the imaginai moult in P. megistus, halves the amount of secretion in the accessory glands.

The activity of glutamate-pyruvate transaminase (GPT) increases regularly as the fourth instar larva of Zabrotes subfasciatus develops into prepupa. On the other hand, glutamate-oxaloacetate transaminase (GOT) activity increases significantly (P < 0.05) during the first 12 hr, and then remains at a sufficiently constant level during the subsequent development of this larval instar except at 36 hr of development. However, at the time of prepupation, the GOT and GPT-activities show a decline, which is subsequently followed by an increase during the rest of the prepupal development. The activity of GOT is quite high during the early pupal life, i.e. up to 120 hr. On the other hand, GPT-activity falls significantly (P < 0.05) during the first 24 hr of pupal life and rise up to 120 hr during pupal development. Once again, in the late pupal development, the transaminases remain very active on account of the faster rate of histogenesis. During early adult life, the GOT and GPT are still active, as the early part of adult life of the insect is physiologically quite vigorous and accordingly the energy requirements of the body at this stage are intense. Subsequently, there occurs a regular attenuation of the activities of both of the transaminases in the aging bruchid.

Investigations were conducted in the greenhouse to evaluate the biological performance of Aphis fabae Scopoli when bred on two varieties of the common bean, Phaseolus vulgaris L. Mean developmental period of the aphid was 7.8 days at 26.5°C (range 15.0–32.5°C) on the bean varieties Mwezi Moja (GLP.10) and Red Haricot (GLP.3). The reproductive life of the aphid averaged 15.3 days (range 11–17 days) during which each mother aphid produced on average 55.2 and 56.2 nymphs on the two bean varieties, respectively. Nymphs (66.2%) were born during the daytime (0600–1800 hr), whereas only 33.8% of the nymphs were produced during the night (1800–0600 hr). There were two peaks of diurnal nymphal production, and more nymphs were born during the morning peak (0600–0800 hr) than during the mid-afternoon peak (1400–1600 hr). A very high rate of A. fabae population increase was observed.

In an experiment to test the efficiency of carbofuran, as furadan 5G, as an oil palm nursery insecticide, its rate of application is recommended at 1.5 g furadan 5G per plant, which had no adverse physiological effects on seedlings. The number of mealybugs/plant was reduced by between 58 and 95% with increasing application of carbofuran, and the percentage of transplantable seedlings increased by about 6%. The percentage of stunted seedlings decreased with decreasing numbers of mealybugs. Major nursery pests identified were Temnoschoita quadrimaculata and mealybugs (Pseudococous sp.). Minor pests identified were Arantia rectifolia, Eulioptera reticulata, Homeogryllus reticulatus and Pyrgomorpha sp.

Some factors affecting oviposition by Plodia interpunctella (Hubner) were studied under various controlled conditions in the laboratory. The effect of temperature, relative humidity, light and mating on oviposition were investigated.

Temperatures of 25 and 30°C were optimal for oviposition. The best condition was 30°C and 80% r.h. at which an average of 315.3 eggs were laid per female during its lifetime. The least favourable temperatures investigated were 15 and 35°C. Relative humidity did not have significant effect on the number of eggs laid at 15 and 25°C but at higher temperatures of 30 and 35°C, high r.h. increased the number of eggs laid by individual moths.

Light regimes of 12 hr light and 12hr darkness (LD) and 24 hr darkness (DD) were more favourable than 24 hr light (LL) for oviposition.

Virgin females laid fewer eggs than mated females while prolonged virginity reduced the number of eggs laid and caused resorption of immature oocytes and retention of ripe eggs in the ovaries.

Field studies revealed the nettle caterpillar, Latoia ( = Parasa) viridissima, to be multivoltine with four discrete generations a year. The maximum egg (1800/100 fronds) and larval (1500/100 fronds) densities were attained in April/May 1980. The pupal population was generally low; the highest recorded density of 54/100 fronds was attained in March 1980 during the first generation.

Samples of larvae and pupae from the field were attacked by parasitoids in the families Bombyliidae, Braconidae, Chalcididae, Chrysididae, Eulophidae, Ichneumonidae and Tachinidae. These contributed to mortalities ranging from 6 to 30%, but their combined action with microorganisms (bacteria and fungi) accounted for 28–65% mortality of the insect.

The biological effects of six insect growth regulators (IGRs) AI3-37634-c, AI3-36877-b, AI3-37603-b, AI3-36807-b, AI3-37837-a and AI3-36809-a against immature stages and adults of Aedes aegypti have been evaluated. According to IC50 values obtained (concentration to inhibit the emergence of 50% of adults), AI3-36809-a (0.02μg/ml) proved to be the most effective compound, followed by AI3-37603-b (0.04μg/ml), AI3-37837-a (0.11μg/ml), AI3-36807-b (0.17 μg/ml), AI3-37634-C (0.48 μg/ml) and AI3-36877-b (1.4 μg/ml), respectively. The results showed also that the duration of the fourth instar larvae of A. aegypti was prolonged when these larvae were exposed to the effective concentrations of the above compounds.

Apart from delayed lethal action, possible effect of the compounds tested on the basal follicle numbers developed by females of A. aegypti which survived after larval treatment with IC50 of the above-mentioned compounds has been considered. Generally, the results indicate that the females treated have more follicles than the untreated ones of similar age and grown under identical conditions.

Laboratory evaluations were conducted for 94 weeks to compare, under static conditions, residue levels maintained in water treated with three polyvinyl chloride pellet formulations of fenitrothion. The results showed that foamed formulation (polyvinyl chloride + dioctyl phthalate + Triton X-100 + ammonium carbonate + citric acid + water + fenitrothion) gave the highest rates in the percentage of fenitrothion released followed by expanded formulation (polyvinyl chloride + dioctyl phthalate + Triton X-100 + fenitrothion), while non-expanded formulation (polyvinyl chloride + dioctyl phthalate + fenitrothion) gave the least.

The records indicated that increasing both the exposure time of formulations tested into the water and the percentage of active ingredient in the present formulations increased the amount of fenitrothion released from these formulations. However, all tested formulations gave low-initial rate of release.

The results showed that there were two rates of release of fenitrothion. In the first step, the non-expanded formulation gave a slow rate of release, expanded formulation gave a moderate rate of release, and foamed formulation gave a fast release. In the second step, the release rate of fenitrothion was slow for all tested formulations.

The larvicidal activity of the pathogen Bacillus thuringiensis H-14 against mosquito larvae of Aedes aegypti (L.) and Culex pipiens L. has been evaluated.

The results showed that the susceptibility of culicine larvae to this pathogen was closely correlated with mosquito species tested and its larval instars. The toxicity curves indicated that the serotype H-14 had a higher pathogenicity against A. aegypti than C. pipiens. LC50 values showed that, for both mosquito species tested, the second instar larvae were more susceptible to the pathogen used than the fourth instar larvae.

Apart from lethal action, larval treatments with B. thuringiensis H-14 led to a decrease in the reproductive potential of female mosquitoes that emerged from these treatments.

Eggs (1, 2 and 3-day-old), larvae (early and late) and 4-day-old pupae of the rice moth, Corcyra cephalonica (Stainton), were treated with 60Co gamma-radiation at doses from 0 to 100 krads. Evaluation of moth radiosensitivity by the survival of treated eggs, larvae and pupae led to the following sequence of stages in order of increasing radioresistance: for the eggs, 1, 2 and 3-day-old; for larvae and pupae, early larvae (5 days after hatching), late larvae (5 days before pupation) and 4-day-old pupae. Twenty five kiloradians was found to be the most likely unit for disinfestation by radiation of C. cephalonica.

Competition between Corcyra cephalonica (Stainton) and Ephestia cautella (Walker) was studied in broken cocoa beans using the two species alone, introduced one before the other and together. Both species of moths cannot co-exist for an extended period and in competition E. cautella becomes extinct. The results offer an explanation of recent evidence that C. cephalonica is rapidly becoming the most important pest of stored cocoa beans in Ghana today.