Environmental & Physical Sciences

Environmental & Physical Sciences Research Papers/Topics

Unexpected diversity of Wolbachia associated with Bactrocera dorsalis (Diptera: Tephritidae) in Africa.

Abstract: Bactrocera dorsalis (Hendel) is an important pest of fruit-bearing plants in many countries worldwide. In Africa, this pest has spread rapidly and has become widely established since the first invasion report in 2003. Wolbachia is a vertically transmitted endosymbiont that can significantly influence aspects of the biology and, in particular, the reproduction of its host. In this study, we screened B. dorsalis specimens collected from several locations in Africa between 2005 and 20...

Antifeedant and ovicidal activities of a new cassane and other compounds from Caesalpinia welwitschiana Oliv. and Caesalpinia bonduc L. against Tuta absoluta (Lepidoptera: Gelechiidae).

Abstract: Methanolic extracts of liana of Caesalpinia welwitschiana and leaves of C. bonduc were found to possess moderate antifeedant and ovicidal activities against Tuta absoluta. Bioassay-guided isolation of constituents from the most active fraction of C. welwitschiana led to the identification of four known compounds [isobonducellin 1a and bonducellin 1 b, intricatinol 2, (-)-epigallocatechin-3-O-gallate 4] and one new constituent [welwitschianic acid 3]. The most active fraction of C...

Smallholder farmers’ knowledge and willingness to pay for insect-based feeds in Kenya

Abstract: Edible insects are increasingly being considered as sustainable alternatives to fish and soybean meals in animal feed because of their high nutritional quality and environmental benefits. However, successful introduction of a new product to the market depends on the target user’s acceptance. Thus, evaluating the potential demand of insect-based feeds would provide relevant information for policy development. The present study assessed farmers’knowledge on edible insects as feed...

Effect of Azadirachta indica and Milletia ferruginea extracts for Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) infestation management in chickpea.

Abstract: Nowadays, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) is becoming a serious insect pest of chickpea in Ethiopia and its management has faced considerable challenges, to improve yields in many crops, in most parts of the world. This experiment was initiated with the objective to evaluate the effectiveness of Azadirachta indica and Milletia ferruginea extracts for the management of H. armigera in chickpea from July to December during 2017 and 2018 cropping season under fie...

Nitrogen fertilizer equivalence of black soldier fly frass fertilizer and synchrony of nitrogen mineralization for maize production

Abstract: The use of black soldier fly frass fertilizer (BSFFF) is being promoted globally. However,information on nitrogen (N) fertilizer equivalence (NFE) value and synchrony of N mineralization forcrop production remains largely unknown. Comparative studies between BSFFF and commercialorganic fertilizer (SAFI) were undertaken under field conditions to determine synchrony of N releasefor maize uptake. The BSFFF, SAFI, and urea fertilizers were applied at the rates of 0, 30, 60,and 100 kg N...

Chemistry and Sensory Characterization of a BakeryProduct Prepared with Oils from AfricanEdible Insects

Abstract: Globally, there is growing interest to integrate insect-derived ingredients into food products.Knowledge of consumer perception to these food products is growing rapidly in the literature,but similar knowledge on the use of oils from African edible insects remains to be established. In thisstudy, we (1) compared the chemistry of the oils from two commonly consumed grasshoppers,the desert locustSchistocerca gregariaand the African bush-cricketRuspolia differenswith those ofolive and...

Cannibalism, oviposition and egg development in the edible long-horned grasshopper, Ruspolia differens (Orthoptera Tettigoniidae) under laboratory conditions

Abstract: Reliance on seasonal wild harvests of the edible long-horned grasshopper Ruspolia differens (Serville) (Orthoptera: Tettigoniidae) needs to be broken through developing efficient mass rearing protocols. This study aimed at boosting productivity of laboratory colonies of R. differens through understanding ways of minimising cannibalism, selecting suitable oviposition substrates and enhancing egg development and hatchability. Firstly, we investigated the extent of cannibalism in a co...

Antifeedant and ovicidal activities of a new cassane and other compounds from Caesalpinia welwitschiana Oliv. and Caesalpinia bonduc L. against Tuta absoluta (Lepidoptera: Gelechiidae)

Abstract: Methanolic extracts of liana of Caesalpinia welwitschiana and leaves of C. bonduc were found to possess moderate antifeedant and ovicidal activities against Tuta absoluta. Bioassay-guided isolation of constituents from the most active fraction of C. welwitschiana led to the identification of four known compounds [isobonducellin 1a and bonducellin 1 b, intricatinol 2, (-)-epigallocatechin-3-O-gallate 4] and one new constituent [welwitschianic acid 3]. The most active fraction of C. ...

Nutritional composition of black soldier fly larvae feeding on agro-industrial by-products

Abstract: Black soldier fly (BSF) larvae, Hermetia illucens L. (Diptera: Stratiomyidae), bio-convert organic side streams into high-quality biomass, the composition of which largely depends on the side stream used.In the present study, BSF larvae were reared on feed substrates composed of dried brewers’ spent grains, each supplemented with either water, waste brewer’s yeast, or a mixture of waste brewer’s yeast and cane molasses to obtain 12 different substrates: barley/water, barley/y...

Forum paper: Insect chemical ecology: Chemically mediated interactions and novel applications in agriculture

Abstract: Insect chemical ecology (ICE) evolved as a discipline concerned with plant–insect interactions, and also with a strong focus on intraspecific pheromone-mediated communication. Progress in this field has rendered a more complete picture of how insects exploit chemical information in their surroundings in order to survive and navigate their world successfully. Simultaneously, this progress has prompted new research questions about the evolution of insect chemosensation and related ...

Efficiency of food-based attractants for monitoring tephritid fruit flies diversity and abundance in mango systems across three West African agro-ecological zones.

Abstract: Food baits are effective and widely used tools for monitoring diversity and abundance of tephritid fruit flies. Four food-baits-Nulure, BioLure, Mazoferm at 3 and 6%, and Torula yeast-were used in multi-lure traps over a 4-yr period in mango orchards in three Benin agro-ecological zones (AEZ) representing a large swath of environments in western Africa. Twelve tephritid fruit fly species were captured during the trials, with the highest richness in the Forest Savannah Mosaic (FSM),...

Farmers’ knowledge and management practices of cereal, legume and vegetable insect pests, and willingness to pay for biopesticides.

Abstract: We utilized data from cereal, legume, and vegetable growers in Kenya and Uganda to assess their knowledge and management practices of common pests and willingness to pay (WTP) for biopesticides. The contingent valuation method was used to assess the WTP and associated factors among 600 and 700 farmers in Kenya and Uganda, respectively. Fall armyworm (Spodoptera frugiperda) was reported as the major maize pest in both countries, while aphids (Aphis spp.) and Tuta absoluta were ranke...

Impact of integrated fruit fly management strategy on food security among smallholder mango farmers in Kenya.

Abstract: Adoption of agricultural innovations is perceived as a key avenue for poverty reduction and improved food and nutritional security in developing countries. The International Centre for Insect Physiology and Ecology (icipe) has developed and implemented a set of Integrated Pest Management (IPM) strategiesin several sub-Saharan African countries aimed at controlling mango infesting fruit flies (Bactrocera dorsalis). Although positive returns from the use of fruit fly IPM have already...

Potential of resampled multispectral data for detecting desmodium–brachiaria intercropped with maize in a ‘push-pull’ system.

Abstract: Poor crop yields remain one of the main causes of chronic food insecurity in Africa. This is largely caused by insect pests, weeds, unfavourable climatic conditions and degraded soils. Weed and pest control, based on the climate-adapted ‘push-pull’ system, has become an important target for sustainable intensification of food production adopted by many small-holder farmers. However, essential baseline information using remotely sensed data is missing, specifically for the ‘pu...

Integrated management of Aphis craccivora in cowpea using intercropping and entomopathogenic fungi under field conditions.

Abstract: Cowpea aphid, Aphis craccivora, is a major cowpea pest. Cowpea–cereal intercrop alone does not effectively manage the pest. Use of pesticides in intercrop leads to health and environmental risks. Fungal-based biopesticides offer a better option because they are environment- and consumer-friendly. This study assessed the combined effect of Metarhizium anisopliae ICIPE 62 and cowpea–maize intercrop against A. craccivora under six treatments: (1) untreated cowpea monocrop, (2) unt...


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