Environmental & Physical Sciences

Environmental & Physical Sciences Research Papers/Topics

The case for integrated pest management in Africa: transition from a pesticide-based approach

Abstract: Pest management in major cropping systems has long been dominated by chemical pesticides in Africa. Smallholder farmers have perceived pesticides as insurance to protect their crops. Consumers are less aware of pesticide-related food-safety issues, and markets providing economic incentives to producers who adopt alternatives to pesticides have been slow to emerge. Hence, overuse of pesticides has been constantly increasing. Although African countries have a number of pesticide-rela...

Sustainable Intensification of Vegetable production using the Cereal ‘Push-pull technology’: benefits and one Health Implications

Abstract: One health’ (OH) is a cross-sectoral approach that addresses human, plant, animal, and environmental health problems. The initiative stems from recognition of the convoluted linkages among global health risks and the need for coherent multipronged countermeasures. For agriculture, environmental degradation and biodiversity depletion wrought by heavy reliance on inorganic inputs to meet the needs of the ever-growing human population, are a matter of societal concern. Agroecologica...

Host–Parasitoid Phenology, Distribution, and Biological Control under Climate Change

Abstract: Climate change raises a serious threat to global entomofauna—the foundation of many ecosystems—by threatening species preservation and the ecosystem services they provide. Already, changes in climate—warming—are causing (i) sharp phenological mismatches among host–parasitoid systems by reducing the window of host susceptibility, leading to early emergence of either the host or its associated parasitoid and affecting mismatched species’ fitness and abundance; (ii) shifti...

Population dynamics and insecticide resistance in Tuta absoluta (Lepidoptera: Gelechiidae), an invasive pest on tomato in Kenya

Abstract: Tuta absoluta feeds on solanaceous plants with preference on tomato. Management of the pest is mostly with chemical insecticides. This study identified insecticide resistant populations and predicted resistance to insecticides. Insecticide resistance development was modelled using system thinking, and system dynamics approaches. The model showed the pest resistance development is alarming with an exponential increase of the resistance strength mostly in recent years. Furthermore, w...

Guarding Vibrations—Axestotrigona ferruginea Produces Vibrations When Encountering Non-Nestmates

Abstract: Abstract: Flower visiting stingless bees store collected pollen and nectar for times of scarcity. This stored food is of high value for the colony and should be protected against con- and that might rob them. There should be high selective pressure on the evolution of mechanisms todiscriminate nestmates from non-nestmates and to defend the nest, i.e., resources against intruders.Multimodal communication systems, i.e., a communication system that includes more than sensory modality ...

First record of the genus Tanaostigma (Hymenoptera, Chalcidoidea, Tanaostigmatidae) from the Afrotropical region with description of three new species

Abstract: The genus Tanaostigma is newly recorded from the Afrotropical region and three new species are described: Tanaostigma lasallei van Noort sp. nov. (South Africa), Tanaostigma mulu van Noort sp. nov. (Kenya) and Tanaostigma ukumbusho van Noort sp. nov. (Kenya). We provide comprehensive images of the holotypes and an illustrated identification key to the African species. New country distribution records are provided for Tanaostigmodes tambotis Prinsloo & LaSalle, 1995. All images pres...

Antennal Enriched Odorant Binding Proteins Are Required for Odor Communication in Glossina f. fuscipes

Abstract: Olfaction is orchestrated at different stages and involves various proteins at each step.For example, odorant-binding proteins (OBPs) are soluble proteins found in sensillum lymph that might encounter odorants before reaching the odorant receptors. In tsetse flies, the function of OBPs in olfaction is less understood. Here, we investigated the role of OBPs in Glossina fuscipes fuscipes olfaction, the main vector of sleeping sickness, using multidisciplinary approaches. Our tissue e...

Cellular and molecular targets of waterbuck repellent blend odors in antennae of Glossina fuscipes fuscipes, Newstead, 1910

Abstract: Insects that transmit many of the world’s deadliest animal diseases, for instance trypanosomosis, find their suitable hosts and avoid non-preferred hosts mostly through olfactory cues. The waterbuck repellent blend (WRB) comprising geranylacetone,guaiacol, pentanoic acid, and δ-octalactone derived from waterbuck skin odor is a repellent to some savannah-adapted tsetse flies and reduces trap catches of riverine species. However, the cellular and molecular mechanisms associated wi...

Towards early response to desert locust swarming in eastern Africa by estimating timing of hatching

Abstract: Desert locust (Schistocerca gregaria) plagues threaten agricultural production, food security and the environment across Africa, the Middle East, and Southwest Asia. Control methods targeting adult desert locusts present significant challenges and financial costs. Recognizing this, we developed a ground-breaking fuzzy set Mamdani type inference model that provides an innovative solution for early warning alerts. The model aids in predicting the juvenile stages of locust development...

Data to understand the biotransfer of heavy metals along the soil-plant-edible insect-human food chain in Africa

Abstract: Data on the biotransfer of heavy metals along the soil-plant-edible insect-human food chain collected along a 60km pollution gradient is presented here. These datasets consists of concentrations of eight heavy metals (Arsenic, Cadmium, Copper, Chromium, Iron, Nickel, Lead and Zinc) in the soils, in five host plants species, and in seven edible insect species determined using Atomic Absorption Spectrophotometry (AAS). Datasets for the daily intake of metals and target hazard quotien...

A fungal‑based pesticide does not harm pollination service provided by the African stingless bee Meliponula ferruginea on cucumber (Cucumis sativus)

Abstract: Stingless bees (Apidae: Meliponini) provide pollination services to crops and produce high–quality honey. The application of agrochemicals during the management of crop pests is an increasing threat to pollina tors and the ecosystem services they provide. Biopesticides are considered as better alternatives; however, there is limited evidence of their impact on stingless bees. We evaluated the effect of the most widely used African fungal biopesticide (Metarhizium anisopliae ICIPE...

Fragmented landscapes affect honey bee colony strength at diverse spatial scales in agroecological landscapes in Kenya

Abstract: Landscape fragmentation and habitat loss at multiple scales directly affect species abundance, diversity, and productivity. There is a paucity of information about the effect of the landscape structure and diversity on honey bee colony strength in Africa. Here, we present new insights into the relationship between landscape metrics such as patch size, shape, connectivity, composition, and configuration and honey bee (Apis mellifera) colony strength characteristics. Remote-sensing-b...

Impact of invasive insects on native insect communities

Abstract: Several biophysical factors are leading to the loss of biodiversity, among them the dominance of exotic invasive species on native communities is important. Their dominance can lead to changes in the structure of insect communities, by competing and displacing native species to other crops or habitats. These changes can impact the herbivore’s natural enemies in invaded areas by diverging them from suitable herbivores and altering their biological control process. The development ...

Floral turnover and climate drive seasonal bee diversityalong a tropical elevation gradient

Abstract: The contribution of seasonality in species communities to elevational diversityof tropical insects remains poorly understood. We here assessed seasonal pat-terns and drivers of bee diversity in the Eastern Afromontane BiodiversityHotspot, Kenya, to understand the contribution of seasonality to elevationalbiodiversity patterns. Bee species and plant species visited by bees wererecorded on 50 study plots in regrowth vegetation across four major seasonsalong two elevation gradients fr...

Global population genetic structure and demographic trajectories of the black soldier fly, Hermetia illucens

Abstract: Background: The black soldier fly (Hermetia illucens) is the most promising insect candidate for nutrient-recycling through bioconversion of organic waste into biomass, thereby improving sustainability of protein supplies for animal feed and facilitating transition to a circular economy. Contrary to conventional livestock, genetic resources of farmed insects remain poorly characterised. We present the first comprehensive population genetic characterisation of H. illucens. Based on ...


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