Environmental & Physical Sciences

Environmental & Physical Sciences Research Papers/Topics

Egg-laying decisions based on olfactory cues enhance offspring fitness in Stomoxys calcitrans L. (Diptera: Muscidae).

Abstract: Selection of oviposition substrate is critical in holometabolous insects. Female stable fies, Stomoxys calcitrans, locate and select vertebrate herbivore dung in which they lay their eggs. However, the preference for vertebrate herbivore dung by S. calcitrans females, its ftness consequences for ofspring, and the semiochemicals used to locate and select oviposition substrates remain unclear. Using oviposition choice tests and life table bioassays we found that gravid female S. calc...

Performance of a Metarhizium anisopliae-treated semiochemical-baited trap in reducing Amblyomma variegatum populations in the field

Abstract: Experiments were carried out to evaluate the efficacy of Metarhizium anisopliae (Metsch.)Sorok. (Ascomycota: Hypocreales)-treated semiochemical-baited traps for control of Amblyomma variegatum Fabriscius (Acari: Ixodidae) under field conditions. Unfed A. variegatum adults (118) were seeded in each 100-m plot and allowed to acclimatise for 3 days. On the fourth day (Day 4), an emulsifiable formulation of M. anisopliae (consisting of 49.5% sterile distilled water, fungal conidia, 49....

Empirical modeling of the impact of climate change on altitudinal shift of major cereal crops in South Tigray, Northern Ethiopia

Abstract: Climate change is expected to alter the growing conditions of agricultural crops. With increasing surface temperature, future suitable areas for crop production will see an altitude shift. Such shift is an adaptation response of crops to climate change. However, in the study area there are a limited number of studies that have dealt with geographical shifts of crops caused by climate change. This study was conducted with the aim of assessing impacts of climate change on altitudinal...

Τhe complete mitochondrial genomes of Ceratitis rosa and Ceratitis quilicii, members of the Ceratitis FAR species complex (Diptera: Tephritidae)

Abstract: Ceratitis FAR is an African species complex comprising insect pests of great economic interest and obscure species limits. Here, we report the mitochondrial genomes of two members of the FAR com-plex, namely Ceratitis rosa and the recently characterized Ceratitis quilicii. A phylogenetic analysis based on PCGs of available Tephritidae mitogenomes is presented. The current mitochondrial sequen- ces from the FAR complex could contribute toward the resolution of phylogenetic relations...

Global risk of invasion by Bactrocera zonata: Implications on horticultural crop production under changing climatic conditions.

Abstract: The peach fruit fly Bactrocera zonata (Saunders) (Diptera: Tephritidae) is an important invasive species causing substantial losses to the horticulture industry worldwide. Despite the severe economic impact caused by this pest in its native and invaded range, information on its potential range expansion under changing climate remains largely unknown. In this study, we employed maximum entropy (MaxEnt) modeling approach to predict the global potential climatic suitability of B. zona...

Mitogenomic analysis of diversity of key whitefly pests in Kenya and its implication to their sustainable management

Abstract: Whitefies (Hemiptera: Aleyrodidae) are devastating agricultural pests of economic importance vectoring pathogenic plant viruses. Knowledge on their diversity and distribution in Kenya is scanty, limiting development of efective sustainable management strategies. The present study is aimed at identifying whitefy pest species present in Kenya across diferent agroecological zones and establish predictive models for the most abundant species in Africa. Whitefies were sampled in Kenya f...

Insight on Fruit Fly IPM Technology Uptake and Barriers to Scaling in Africa

Abstract: Tephritid fruit flies are considered one of the world’s most notorious pests of horticultural crops, causing extensive direct and indirect damage. Over the past two decades, a comprehensive, integrated pest management (IPM) package for the management of a plethora of fruit fly pests, including Bactrocera dorsalis, B. latifrons, B. zonata, Ceratitis cosyra, C. rosa, C. fasciventris, C. quilici, C. capitata, Dacus spp. and Zeugodacus cucurbitae, has been developed, disseminated and...

Diversity of fall armyworm, Spodoptera frugiperda and their gut bacterial community in Kenya.

Abstract: Background The invasive fall armyworm, Spodoptera frugiperda (J.E. Smith) is a polyphagous pest that causes widespread damage particularly to maize and sorghum in Africa. The microbiome associated with S. frugiperda could play a role in the insects’ success and adaptability. However, bacterial communities in S. frugiperda remain poorly studied. Methods We investigated the composition, abundance and diversity of microbiomes associated with larval and adult specimens of S. frugiper...

Field evaluation of a new third generation push-pull technology for control of striga weed, stemborers, and fall armyworm in western Kenya

Abstract: Production of cereal crops in sub-Saharan Africa is threatened by parasitic striga weeds and attack by stemborers and the invasive fall armyworm (FAW), compounded by increasing hot and dry conditions. A climate-smart push-pull technology (PPT) significantly reduces effects of these biotic challenges. To improve further resilience of the system to climate change, more adapted and suitable companion plants were identified and integrated in a new version of PPT, termed ‘third genera...

Agro-Dealers’ Knowledge, Perception, and Willingness to Stock a Fungal-Based Biopesticide (ICIPE 20) for Management of Tuta absoluta in Kenya

Abstract: In sub-Saharan Africa (SSA), tomato is an economically important crop that contributes not only to employment and income, but also food security. Like the rest of the SSA countries, tomato production in Kenya is constrained mainly by pests and diseases, key among them being the tomato leaf miner (Tuta absoluta), which can cause 80–100% losses if not properly managed. To suppress this pest, the International Centre of Insect Physiology and Ecology (ICIPE) and partners are introduc...

Trypanosoma brucei rhodesiense Transmitted by a Single Tsetse Fly Bite in Vervet Monkeys as a Model of Human African Trypanosomiasis.

Abstract: We have investigated the pathogenicity of tsetse (Glossina pallidipes)-transmitted cloned strains of Trypanosoma brucei rhodesiense in vervet monkeys. Tsetse flies were confirmed to have mature trypanosome infections by xenodiagnosis, after which nine monkeys were infected via the bite of a single infected fly. Chancres developed in five of the nine (55.6%) monkeys within 4 to 8 days post infection (dpi). All nine individuals were successfully infected, with a median pre-patent per...

The Glossina Groteolytic lectin (Gpl) Gene is Expressed only in Members of Glossina Species.

Abstract: Differentiation of bloodstream-form trypanosomes into procyclics in tsetse flies (Diptera: Glossinidae) is a crucial step in the establishment of midgut infections. A number of factors have been implicated in the transformation process, including enzymes and lectins or lectin-like molecules. Recently, Glossina proteolytic lectin (Gpl) gene, which encodes a protein with both lectin and trypsin activities has been shown to stimulate transformation of bloodstream-form trypanosomes int...

A deadly encounter: Alien invasive Spodoptera frugiperda in Africa and indigenous natural enemy, Cotesia icipe (Hymenoptera, Braconidae)

Abstract: The invasion and wide spread of Spodoptera frugiperda represent real impediments to food security and the livelihood of the millions of maize and sorghum farming communities in the sub-Saharan and Sahel regions of Africa. Current management efforts for the pest are focused on the use of synthetic pesticides, which are often economically unviable and are extremely hazardous to the environment. The use of biological control offers a more eco-nomically and environmentally safer altern...

Electroantennogram and machine learning reveal a volatile blend mediating avoidance behavior by Tuta absoluta females to a wild tomato plant

Abstract: Tomato cultivation is threatened by the infestation of the nocturnal invasive tomato pinworm, Tuta absoluta. This study was based on field observations that a wild tomato plant, Solanum lycopersicum var. cerasiforme, grown in the Mount Kenya region, Kenya, is less attacked by T. absoluta, unlike the cultivated tomato plants like S. lycopersicum (var. Rambo F1). We hypothesized that the wild tomato plant may be actively avoided by gravid T. absoluta females because of the emission o...

Assessing the Environmental Suitability for Transhumance in Support of Conflict Prevention in the Sahel Open Access

Abstract: Increasing conflicts between farmers and pastoralists continue to be a major challenge in the Sahel. Political and social factors are in tandem important underlying determinants for conflicts in the region, which are amplified by the variability and scarcity of natural resources, often as a result of climate variability and climate change. This study aimed at holistically assessing the main environmental parameters that influence the patterns of seasonal migratory movements (transh...


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