Jatropha curcas L. is a stem-succulent shrub that produces high concentrations of seed oils that are convertible into biodiesel. In this study, the incidence of four insect pests on Jatropha, Strabala rufa, Gnathamitermes tubiformans, Pempelia morosalis, and Acanthoplus discoidalis was recorded over three years in a semi-arid climate in Gaborone, Botswana. The occurrence of these insects was concentrated in the summer season from October to April, while lower numbers of all species were found in May as the temperature began to reduce towards the winter season, suggesting that insect pests of Jatropha exhibit a unique temporal pattern in this region. A considerable variation was observed among Jatropha accessions regarding the insect pest occurrence, indicating a vast difference in the susceptibility to insect pests among Jatropha accessions.

The study reported here evaluated the distribution, relative abundance, and malaria transmission potential of Anopheles mosquitoes at 30 sites representing different ecological strata in western Kenya. Seasonal variation in anopheline densities and transmission potential, as expressed by Entomological inoculation rates (EIR), was investigated. Of the 6491 indoor resting anopheline mosquitoes collected at the 30 sites, 91.3 % (n = 5926) were An. gambiae s.l. and 8.7 % (n = 565) were An. funestus with an average house density of 6.58 and 0.63, respectively. Analysis of the data indicated significant variation in mosquito densities between study sites, species and season. High densities of both An. gambiae and An. funestus were recorded in the northern and northeastern parts of the district, while generally low densities were recorded in the south. Anopheles gambiae s.s. and An. arabiensis comprised 60.3 % (n = 3573) and 39.7 % (n = 2352) of the total number of An. gambiae s.l. mosquitoes collected, respectively. The composition of the An. gambiae s.l. sibling species showed temporal and spatial variation. Entomologic inoculation rates were estimated at 1.55 and 0.12 infective bites per person per month for An. gambiae s.l. and An. funestus, respectively. This study reveals considerable seasonal and site-specific variation in vector distribution, composition and transmission potential. Application of control interventions must therefore consider seasonal variations since the vectorial system changes quite rapidly over a short period of time.

The red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier), is one of the most destructive pests of date palm in United Arab Emirates. We conducted field trials in Abu Dhabi from May 2010 to April 2011, to evaluate the effect of weekly stirring of water and dates in the RPW pheromone trap on adults captured in brown and white traps, using a randomized complete block design with four treatments and five replications. Each trap contained: (1) a dispenser of the RPW male aggregation pheromone (Ferrolure™) containing 700 mg of the active ingredient (4-methyl-5-nonanol (90%) + 4-methyl-5-nonanone (10%)) at 95% purity; (2) an ethyl acetate (EA) dispenser (Weevil Magnet™) containing 40 ml of the active ingredient of EA at 98% purity; (3) 350 g of fodder date fruits; and (4) 4 L of water. Mean adults captured in white traps was 22.5 ± 0.50 and 16.8 ± 0.41 adults/trap/month with and without stirring, respectively, while in brown traps the mean was 39.9 ± 1.31 and 28.3 ± 0.51, respectively. The overall mean of adults captured was 31.2 ± 6.21 and 22.6 ± 4.81 adults/trap/month with and without stirring, respectively. The highest number of weevils caught was in the brown traps with stirring, while the lowest was in the white traps without stirring. The results of these trials suggest the use of brown traps containing aggregation pheromone, 350 g of date fruits, EA and water. It is necessary to stir the water with dates in the traps to increase their efficacy.

At intervals of 2 months over 1 year, 64 royal cells were removed from mounds of Macrotermes michaelseni to find out whether a new royal pair was produced. In five mounds replacement reproductives were found. Young reproductives from incipient laboratory colonies were never accepted as replacements if they were introduced after the removal of the primary reproductives. One out of 10 royal pairs was accepted if the royal cell was introduced immediately after removal of the original one, and three out of 10 survived if the royal cell was introduced 1 week after the removal of the original one.

Replacement reproductives were only produced when nymphs or alates were in the nest at the time the primary reproductives were removed. It was not possible to find out at what time after the removal a new royal pair was accepted but measurements of the replacement queens showed that they can become fully physogastric within 7 months.

As an important measure for increasing grain production, hybrid sorghum has been cultivated in the whole area of the Peoples Republic of China since 1970. Over the past 10 years the sorghum shootfly has gradually become the worst pest of sorghum in several places in the southern parts of China. In 1973, some regions of Gung Dong, Gui Chou and Gung Xi Provinces were affected by the shootfly with a rate of 30% for the heavier damage, and a few even exceeding 90%.

Essential oil of sweetflag, Acorus calamus L. was fed (in artificial diet) to the variegated cutworm, Peridromo soucia Hubner, to assess its antifeedant and growth inhibitory effects. The oil decreased food consumption and larval growth in a dose-dependent manner in both neonate (first instar) and second instar larvae. Calamus oil applied to cabbage leaf discs significantly inhibited feeding by fourth and fifth instar larvae in a choice test. Nutritional experiments with fourth instar larvae using topical application or dietary exposure confirmed that sweetflag oil induces both antifeedant and growth inhibitory effects in Peridroma saucia, the latter possibly being independent of feeding behaviour.

Various species of sandflies were collected from outdoor natural resting sites from three districts in Kenya which are endemic for kala-azar (Machakos, West Pokot and Baringo). Their blood-meals were analysed to find out host preferences. Female fed-flies were dissected for parasitological investigation. Lizards from these areas were also trapped and blood and internal organs were examined and cultured for isolation of leishmania parasites. Only the lizards obtained from West Pokot and Baringo revealed leishmania parasites in cultures. Bloodmeal analysis showed that Phlebotomus anten-natus, P. bedfordi, P. schwetzi, P. africanus, P. martini, P. affinis and P. rodhaini fed on reptiles. Additionally, promastigotes were seen and isolated from these sandfly species. The disease incidence appears to be less in areas where leishmania parasites were encountered both in lizards and the sandflies in the same locality.

The termite Macrotermes herus builds domed earth mounds with no external openings. The internal structure is described here. There is no specialized ventilation system in the mound, unlike those of other Macrotermes species.

Efficacy of olfactory attractants incorporated in biconical traps to enhance the catch size of Glossina pallidipes Austen was investigated. Preliminary studies considered the effectiveness of a mixture of waste products from buffalo (Syncerus caffer) and that of warthog (Phacochoerus aethiopicus). The results were compared with the known tsetse olfactory attractants, carbon dioxide and acetone. When the waste product components from buffalo were used in the traps separately, buffalo urine was found to be by far the most effective. This component, used in its natural state inside the trap, increased G. pallidipes catches almost 10-fold when compared with the control catch.

The presence of biofertilizers can affect the life and movement of subterranean organisms in the soil. In the current study, the effect of three biofertilizers (Unigrow, Rhizogold and Rhizogold Plus) alone and in combination with diatomaceous earth (DE) and insecticides on mortality and movement of subterranean termites, Coptotermes heimi (Wasmann), was investigated under laboratory conditions. The mortality of termites in soil mixed with biofertilizers was low as compared to the control treatment, which led to significant mortality. Length of galleries formed by termites with the addition of Unigrow in the soil was significantly higher as compared to the other two biofertilizers and control treatments. Mortality increased in the presence of insecticides and DE in the soil substrate. Unigrow mixed soil having chlorfenapyr had maximum mortality and minimum gallery length followed by Rhizogold and Rhizogold Plus. The addition of DE and insecticide further enhances mortality, and we recommend that some toxic elements should be incorporated in biofertilizers to control subterranean termites.

A survey was conducted in Ibadan, Nigeria, between 1 November and 30 December 2000 to examine the mango mealybug Rastrococcus invadens Williams infestation. Results obtained prompted another study in which the population of R. invadens and its parasitism were monitored from January 2001 to December 2005 on smoke-polluted infested mango trees after relocation of smoke sources. A third study was conducted between January and April 2007 in Ibadan, Nigeria, where mealybug-infested mango trees were searched for and the levels of pollution around them characterized using a derived rating scale. The survey results showed that only 7.5% of a total of 489 mango trees examined in 2001 were infested with mango mealybug and were located in exhaust, car park, motorway or converging environments. In study 2, the mango mealybug population significantly (P < 0.05) declined, and parasitism significantly increased on trees from where pollution sources were relocated. All the 86 mango mealybug-infested trees scouted for in study 3 were located in smoke-polluted areas. Significantly higher numbers of infested trees and mealybug population, and significantly lower parasitism levels were found on mango trees in exhaust areas, compared with others. Pollution level was correlated with mealybug population (positively) and parasitism (negatively) in 2000 and 2007. Whereas mealybug population gradually built up on hitherto clean trees where pollution sources were relocated, parasitoid activity seemed to be enhanced by the relocation of smoke sources. The effectiveness and conservation of the parasitoids may therefore depend on the air quality around the infested trees.

Insect species can respond adaptively to stress temperature conditions including both thermal limits and reaction norms. In this study, we considered two populations of the whitefly Bemisia tabaci (Gennadius), in which adaptive differentiation was detected for tolerance to upper thermal limits. These two populations are found in two regions of Colombia with climatic differences: the Caribbean region with high environmental temperatures and the Southwest region with lower temperature regimens. We assessed the thermal responses to a range of 1 h heat shocks (37, 39, 41, 43 and 44 °C) performed below the thermal limits for this species. Thermal responses were measured using three life-history traits involved in fitness: survival, fecundity and viability of the offspring after heat shocks. Survival or fecundity as a response to heat shocks did not differ among populations; however, there were significantly different responses for viability between populations. The Southwestern population showed higher viability responses to low heat shocks than the Caribbean population. This relationship suggests a potential trade-off, which appears to be associated with climatic regions. In addition, these results suggest that adaptation under thermal limits does not necessarily involve similar responses throughout the reaction norm. A potential ongoing evolutionary response is taking place through the thermal reaction norms for viability after the invasion by this pest in Colombia.

Grass pea Lathyrus sativus L. plays a major role in the nutrition of many poor people in Ethiopia. However, the crop suffers heavy damage by pea aphids Acyrthosiphon pisum (Hemiptera: Aphididae). To test potentially more sustainable and harmless alternatives to the commonly used insecticides, some botanicals (neem, garlic and hot pepper), soap, kerosene and the aphicide pirimicarb, were tested for their efficacy against A. pisum at Wondata village, close to the town of Bahir Dar, in northwestern Ethiopia, from 1999 to 2002. After pirimicarb, hot pepper was consistently the most effective botanical in controlling the pea aphid in terms of both pea aphid population as well as grain yield. Compared to the untreated control, there was up to 83 and 55% lower aphid population on pirimicarb- and hot pepper-treated plots in the 2000/2001 cropping season, respectively. There was also up to 93 and 54% higher grain yield on plots treated with pirimicarb and hot pepper extract, respectively. Soap was less effective, while kerosene caused phytotoxicity. Infestation levels increased with advancing maturity of the crop, rising exceptionally suddenly and dramatically near crop maturity. Combined ANOVA over years and crop growth stages indicated that aphid populations varied with years and growth stages. In 2001/2002, aphid populations were higher and grain yields were lower compared with the other years. Percentage parasitism of aphids was significantly higher on pirimicarb-treated plots (∼40%) than other treatments (<20%). Parasitism was essentially a late-season occurrence. Predator population, especially of ladybird beetles (Adonia spp.), was especially higher on hot pepper- and garlic-treated plots, and lowest on pirimicarb treated plots. Grain yield was positively correlated with level of aphid parasitism, ladybird beetle population and number of pods per plant, and strongly negatively correlated with aphid population. In conclusion, a fresh extract of hot pepper sprayed at the rate of 70 ml/4 m2 was selected for further research on rate, frequency and cost of application.

An account of the history of tick control in Uganda is given. It is presented in three phases. Phase one covers the years 1935–1970, being a period of relative stability, while phases two and three cover the periods 1971–1985, characterized by wars and political instability, and 1986 to-date, years of calm and national rehabilitation, respectively.

Mention is also made on the future strategies for the control of ticks based on new technologies and earlier experience.

Epidinocarsis lopezi an exotic parasitoid to Africa, was first released to control the cassava mealybug (CM), Phenacoccus manihoti, at IITA (Ibadan) in November 1981, and a year later at Abeokuta, both in southwestern Nigeria. Population dynamics study of CM and its natural enemies was conducted for 4 years. CM population peaks usually occurred during the second half of the dry season (January–April). E. lopezi was the only natural enemy that was found during the whole year and in high densities. Parasitization rates of E. lopezi alternated with CM densities, thus suggesting a regulatory effect on CM populations by this parasitoid. CM populations were drastically reduced in release fields when compared with control fields. Subsequently CM populations have been maintained below injury levels for 4 years. E. lopezi is considered an efficient parasitoid of the CM.

Bionomics, morphometric measurements and partial mitochondrial cytochrome oxidase I gene (mtCOI) sequences were examined for a population of Bemisia afer (Priesner & Hosny) (Hemiptera: Aleyrodidae) collected from cassava in Uganda. The development of the eggs, first to fourth instar nymphs and adults required respectively, 12, 31 and 10 days, with a total life duration of approximately 53 days on the cassava cultivar Ebwanateraka. Each female laid one egg per day for 13 days and about 40% of the eggs failed to develop into adults. The male: female sex ratio was 1:4. The length and width of the four nymphal instars were positively correlated (correlation coefficient=0.97). Females were bigger than males and the sexes differed significantly based on body length (P<0.001) and width (P<0.001). Overlaps in their body sizes, however, makes sex assignment based on size alone unreliable. The B. afer population shared 68% mtCOI sequence (817 nucleotides) identity with a cassava Bemisia tabaci population (Namulonge) from Uganda. This is the first study on B. afer fecundity and morphometrics, and the variability that might exist in this species is discussed.

The biology of the aphid, Cerataphis variabilis H.R.L., on Raphia hookeri Mann & Wendl., was studied in the laboratory and the field using a ‘clip-on’ cage and a sleeve cage. The first instar lasted 5.1 days. The second and third instars each lasted 2.45 days, while the fourth instar lasted 2.4 days. The total developmental period of the nymphs was 11.3 days at 26.4 ± 1.43°C and r.h. 83 ± 1.46%; 11.6 days at 26.4 ± 1.63°C and r.h. 85 ± 1.19%; 12.9 days at 27.9 ± 1.04°C and r.h. 75.5 ± 1.64%; 12.95 days at 27.8 ± 0.33°C and r.h. 69 ± 1.23%; 15 days at 21.4 ± 0.58°C and r.h. 45 ± 1.77%. These periods were significantly different at 5% level (LSD = 0.59 days). The higher the temperature and relative humidity the shorter the developmental period (with temperature: r = −0.69, 20.8–28.9°C; r.h.: r = −0.97, 43.2–86.2%). The number of progeny per adult ranged from 54 to 60 in a period of 28–31 days. The longevity ranged from 31 to 34 days.

Upwind flight has been elicited in tsetse, Glossina morsitans exposed to host odour and to active components of host odour (carbon dioxide, acetone and 1-octen-3-ol) in a wind tunnel. With the exception of octenol the odours also produce marked kinetic effects in G. morsitans, G. austeni, G. pallidipes and G. palpalis. Threshold concentrations for G. morsitans are in the region of 0.2% for ox odour, 0.01% for carbon dioxide and 400 μgl−1 for acetone.

Thirty-five pearl millet cultivars of short, medium and long maturity cycle were screened in Senegal during 1985–1986 crop seasons to study field reaction to the attack of stalk borer, Coniesta (Acigona) ignefusalis Hmps.; spike worm, Heliocheilus (Raghuva) albipunctella De Joannis; millet midge, Geromyia penniseti Felt; head smut, Tolysporium penicillariae Bref; and ergot, Claviceps fusiformis Lov. Insect and disease incidence varied considerably depending upon cultivar maturity cycle. Least susceptible cultivars were IBV-8001 and P8 against spike worm; Zalla, NKK, P8 and M2D2 against head smut, and Ex-Darou against ergot. Cultivation of IBV-8001 has been suggested in northern and central Senegal. However, studies on identification and utilization of resistance sources of wide genetic diversity and multilocational tests may be necessary.