Journal and Journal Articles: Recent submissions

Now showing items 1981-2000 of 5273

    • Fate of aflatoxins and fumonisins during the processing of maize into food products in Benin 

      Fandohan, P.; Zoumenou, D.; Hounhouigan, D.J.; Marasas, W.F.O.; Wingfield, M.J.; Hell, K. (2005-02-15)
      The fate of aflatoxins and fumonisins, two mycotoxins that cooccur in maize, was studied through the traditional processing of naturally contaminated maize in mawe, makume, ogi, akassa, and owo, maize-based foods common in Benin, West Africa. Levels of total aflatoxin and fumonisin were measured at the main unit operations of processing, and the unit operations that induce significant reduction of mycotoxin level were identified. Overall reduction of mycotoxin level was more significant during the ...

    • Biological control of cassava green mite with exotic and indigenous phytoseiid predators—effects of intraguild predation and supplementary food 

      Onzo, A.; Hanna, R.; Negloh, K.; Toko, M.; Sabelis, M.W. (2005)
      Intraguild predation, one aspect of predator–predator interaction, has received in recent years increasingly greater attention because of mounting evidence of the impact of predator–predator interactions on the structure of ecological communities and biological pest control. In laboratory experiments, we determined if intraguild predation occurs between Typhlodromalus manihoti and Euseius fustis, two phytoseiid mite predators of the cassava green mite Mononychellus tanajoa on cassava in Africa, ...

    • Sensory texture profiling and development of standard rating scales for pounded yam 

      Otegbayo, B.; Aina, J.; Sakyi‐Dawson, E.; Bokanga, M.; Asiedu, Robert (2005-12)
      This study evaluated sensory texture profile analysis (STPA) as an objective method for characterizing the texture attributes of “pounded yam,” a popular dish in West Africa made by peeling yam, boiling, pounding and kneading it into a glutinous dough. Panelists were carefully selected and trained to assess the texture attributes of pounded yam. Standard rating scales were developed from local foods that are common in Nigeria, and the foods were used as descriptors to exemplify the texture attributes ...

    • Potential contributions of biotechnologies in the management and conservation of forest resources of the Congo basin 

      Sonwa, D.J.; Weise, S.F.; Nkongmeneck, A.B.; Nwaga, D.; Zapfack, L.; Nzooh, L.Z.; Janssens, M.J.J. (2005-03)
      A review of the potential for biotechnology to contribute to the management and conservation of forest resources in the Congo Basin suggests that biotechnology needs to be seen as a complementary tool to the traditional management programme not as a substitute. In addition, there is a pressing need to support human and material capacity building linked to the application of biotechnology for forestry resource management in the Basin.

    • First report of the fall armyworm, Spodoptera frugiperda (J E Smith) (Lepidoptera: Noctuidae), an alien invasive pest on maize in India 

      Sharanabasappa, S.D.; Kalleshwaraswamy, C.M.; Asokan, R.; Swamy, H.M.M.; Maruthi, M.S.; Pavithra, H.B.; Hegbe, K.; Navi, S.; Prabhu, S.T.; Goergen, G. (2018)
      The global agriculture often faces new threats from invasive alien insect pests, pathogens, weeds etc requiring immediate attention and co-operative action to manage the pestilence. In this regard, the fall armyworm (FAW), Spodoptera frugiperda is a notorious pestiferous insect with high dispersal ability, wide host range and high fecundity that make it one of the most severe economic pests. The FAW has been restricted to the Americas and recently in 2016 reported from various countries in Africa, ...

    • Operationalscale application of entomopathogenic fungi for control of Sahelian grasshoppers 

      Kooyman, C.; Bateman, R.P.; Langewald, J.; Lomer, C.J.; Ouambama, Z.; Thomas, M.B. (1997)
      Locusts and grasshoppers regularly threaten agricultural production across large parts of the developed and developing worlds. Recent concerns over the health and environmental impacts of standard chemical control measures have led to a demand for alternative, more environmentally benign control technologies. Here we present the results of a field study to investigate the potential of inundative biological control for control of grasshoppers in the Sahelian region of Africa. The biocontrol agent ...

    • Mulching effect of plant residues of chemically contrasting compositions on soil organic matter content and cation exchange capacity 

      Tian, G.; Brussaard, Lijbert (1997)
      Effects of five types of plant residues [Acioa, presently Dactyladenia barteri, Gliricidia sepium, and Leucaena lecocephala prunings, maize (Zea mays) stover and rice (Oryza sativa) straw] applied as mulch on soil organic matter (SOM) content and effective cation exchange capacity (ECEC) were studied on an Alfisol in the humid tropics. Plant residue mulch resulted in a decline in SOM and ECEC during two years of cropping following six years of grass fallow. Rice straw mulch resulted in less and ...

    • Improved polyploid Musa germplasm developed by IITA through ploidy manipulations 

      Ortiz, R.; Vuylsteke, D. (1997)
      Plantain and banana (Musa spp. L.) polyploid hybrids have been obtained after interspecific hybridisation and ploidy manipulations (i.e., interploidy crosses). The identification of promising hybrids for cultivar release requires their field testing to assess agronomic performance. The potential of new polyploid hybrid selections was evaluated in comparison with their triploid ancestral landraces in two trials consisting of 25 and 30 genotypes, respectively. Twenty-six primary tetraploids, seven ...

    • Microsatellite markers for molecular breeding of Musa 

      Crouch, J.H.; Crouch, H.K.; Ortiz, R.; Jarret, R.L. (1997)

    • Trophic influences on survival, development and reproduction of Hyperaspis notata (Col., Coccinellidae) 

      Staubli Dreyer, B.; Neuenschwander, P.; Baumgaertner, J.; Dorn, S. (1997)
      The coccinellid, Hyperaspis notata Mulsant, is associated with the mealybugs Phenacoccus manihoti Mat.‐Ferr. and P. herreni Williams, on cassava in southern Brazil and the highlands of Colombia. Brought to Africa to help control the accidentally introduced P. manihoti, its range of target prey and plant food sources as well as its performance under conditions of food scarcity were investigated in the laboratory. H. notata showed a moderately narrow food spectrum which should allow survival in ...

    • Grasshopper control in the Sahel: Farmer perceptions and participation 

      Stonehouse, J.M.; Gbongboui, C.; Groot, A. de; Lomer, C.; Ly, S.; Tijani; Maiga, I. (1997)
      This study used farmers' responses to a questionnaire to investigate the practices they used against grasshoppers, locusts and other pests, the reasons for their choices, and the differences between the perception and control of grasshoppers vis-à-vis other pests. 313 farmers were interviewed in the Sahelian zones of Benin, Mali and Niger. The perceived relative and absolute gravity of pests, and the techniques used against them, varied between areas. Insect control techniques requiring cash ...

    • Suitability of West African gramineous stemborers for the development of Cotesia species (Hymenoptera: Brachonidae) 

      Hailemichael, Y.; Schulthess, F.; Smith, W.; Overholt, W.A. (1997)
      The palaeotropical, gregarious, endoparasitic braconids Cotesia sesamiae, Cotesia flavipes and Cotesia chilonis were recently imported into Benin as candidates for biological control of stem and cob borers of maize. Host acceptability and host suitability of six gramineous borers occurring in western Africa, namely the noctuids Sesamia calamistis, Sesamia poephaga, Busseola fusca and the pyralids Coniesta ignefusalis, Eldana saccharina andMussidia nigrivenella, to these candidate parasitoids was ...

    • Selection for the improvement of maize yield under moisture deficits 

      Fischer, K.S.; Edmeades, G.O.; Johnson, E.C. (1989)
      Throughout the lowland humid tropics, unpredictable periods of non-protracted drought are responsible for significant reductions in maize (Zea mays L.) yield, and losses may be disastrously large if drought coincides with the period around flowering. This study was conducted to develop and evaluate a selection procedure to improve the drought resistance of maize populations grown under limited moisture supply, particularly around flowering. Eighty-five full-sib progenies of the tropical lowland ...

    • Effect of the bs 1 gene in plantainbanana hybrids on response to black sigatoka 

      Craenen, K.; Ortiz, R. (1997)
      Use of resistant host genotypes is an important component of an integrated approach to control black sigatoka, a disease caused by the fungus Mycosphaerella fijiensis Morelet. The objective of the present research was to determine the role of the major gene for black sigatoka resistance (bs1) in the host response to this disease. Euploid hybrids with a known genotype for the bs1 locus were derived from triploid-diploid crosses of two French plantains and a diploid wild banana, and were assessed ...

    • Seasonal meteorological factors influencing the annual flight cycle ofProstephanus truncatus (Coleoptera: Bostrichidae) and its predator Teretriosoma nigrescens (Coleoptera:Histeridae) in Benin 

      Borgemeister, C.; Meikle, W.G.; Scholz, D.; Adda, C.; Degbey, P.; Markham, R.H. (1997)
      Investigations were carried out in southern Benin on the annual flight cycle and the effects of weather variables on the flight activity of Prostephanus truncatus (Horn) and its natural enemy, Teretriosoma nigrescens Lewis. Two seasonal peaks in flight activity of P. truncatus were observed, one between the end of December and the beginning of January and a second one between May and June. Teretriosoma nigrescens showed a single delayed peak in June, approximately six weeks after the major peak ...

    • Effect of use of savanna tree leaves as mulch materials on germination and growth of selected annual crop seedlings 

      Hayashi, Y.; Carsky, R.J. (1997)
      Leaves of indigenous and exotic tree species adapted to the climatic conditions of the northern Guinea savanna of West Africa were evaluated for use as a mulch material and screened for their effect on germination and early growth of two varieties each of soybean (Glycine max), cowpea (Vigna unguiculata), maize (Zea ways), sorghum (Sorghum bicolor) and millet (Pennisetum glaucum). Seed germination, and radicle and shoot fresh weight were examined after 7 days of incubation in petri dishes with ...

    • Agricultural soils as a sink to mitigate CO2 emissions 

      Paustian, K.; Andren, O.; Janzen, H.H.; Lal, R.; Smith, P.; Tian, G.; Tiessen, H.; Noordwijk, M. van; Woomer, P.L. (1997)
      Agricultural soils, having been depleted of much of their native carbon stocks, have a significant CO2 sink capacity. Global estimates of this sink capacity are in the order of 20-30 Pg C over the next 50-100 years .Management practices to build up soil C must increase the input of organic matter to soil and/or decrease soil organic matter decomposition rates. The most appropriate management practices to increase soil C vary regionally dependent on both environmental and socioeconomic factors

    • Protein quality of raw and autoclaved cowpeas: Comparison between some insect resistant and susceptible varieties 

      Umoren, U.E.; Tewe, O.O.; Bokanga, M.; Jackai, L.E.N. (1997)
      A comparative study was conducted with four improved cowpea (2 pod bug resistant and 2 susceptible) varieties to assess the effect of autoclaving at 105 ~ under 15 psi for 30 min on their protein quality, as measured by the levels of some antinutritional factors and performance of rats fed the different cowpea diets. Also, the relationships between antinutrients in the cowpeas and protein quality indicators were examined. Results showed that autoclaving completely eliminated trypsin inhibitor, ...

    • Variability in susceptibility to simulated sunlight of conidia among isolates of entomopathogenic hyphomycetes 

      Fargues, J.; Goettel, M.S.; Smits, N.; Ouédraogo, A.; Vidal, C.; Lacey, L.A.; Lomer, C.J.; Rougier, M. (1997)
      The influence of simulated sunlight on survival of conidia of 4 species of entomopathogenic Hyphomycetes was investigated. Conidia from 65 isolates ofBeauveria bassiana, 23 ofMetarhizium anisopliae, 14 of Metarhizium flavoviride and 33 isolates of Paecilomycesfumosoroseus were irradiated by artificial sunlight (295 to 1,100 nm at an ultraviolet-B irradiance of 0.3 W m -2) for 0, 1, 2, 4 and 8 h. Survival was estimated by comparing the number of colony forming units (CFU) produced by conidia exposed ...

    • Exchanging natural enemies species of lepidopterous cereal stemborers between African regions 

      Schulthess, F.; Bosque-Pérez, N.A.; Chabi-Olaye, A.; Gounou, S.; Ndemah, R.; Goergen, Georg E. (1997)
      Difficulties of identification of natural enemies of cereal stemborers for 'redistribution' in Africa are discussed. Tritrophic level studies on wild and cultivated habitats of borers and beneficial species are needed to judge the impact of a natural enemy species in the cropping system. Areas witli low Pest pressure which are climatically favorable for Pest development may be selected for study. Based on the results of various countrywide surveys to map the relative importance of Sesaniia calnmistis ...