Biological Science Research Papers/Topics

Mutation EthAW21R confers co-resistance to prothionamide and ethionamide in both Mycobacterium bovis BCG and Mycobacterium tuberculosis H37Rv

Abstract Ethionamide (ETA) and prothionamide (PRO) are interchangeably used in tuberculosis (TB) chemotherapy regimens. Subtle discrepancies between biochemical and genetic information on the modes of sensitivity and resistance of isoniazid (INH) and ETA warrants further studies. We report a new mutation – EthAW21R – in Mycobacterium bovis Bacillus Calmette-Guérin that corresponds with co-resistance to both PRO and ETA, which to the best of our knowledge has not been reported before. Ou...

Diversity and Abundance Patterns of Amphibians in Rehabilitated Quarries of Bamburi Near Mombasa (Kenya)

Abstract Amphibians are sensitive to changes in the environment and are, therefore, excellent indicators of success in restoring degraded habitats. As such, a clear understanding on how amphibian populations respond to changes in the environment is required. In order for conservationists to establish if the declining trends are changing, biodiversity recovery studies are essential especially in reclaimed habitats. This study focused on the recovery of amphibians, particularly on frogs, in re...

The Contribution of Occult Precipitation to Nutrient Deposition on the West Coast of South Africa

Abstract The Strandveld mediterranean-ecosystem of the west coast of South Africa supports floristically diverse vegetation growing on mostly nutrient-poor aeolian sands and extending from the Atlantic Ocean tens of kilometers inland. The cold Benguela current upwelling interacts with warm onshore southerly winds in summer causing coastal fogs in this region. We hypothesized that fog and other forms of occult precipitation contribute moisture and nutrients to the vegetation. We measured occu...

Desertifilum fontinale sp. nov. (Oscillatoriales, Cyanobacteria) from a warm spring in East Africa, based on conventional and molecular studies

Abstract Desertifilum is a filamentous cyanobacterium of crusts and biofilms, recently described from the extreme hot and dry Thar Desert in north–western India. A new species was isolated from a warm spring near Lake Bogoria, Kenya and was characterised by light and electron microscopy and phylogenetically using the 16S rRNA gene, beta and alpha subunits including intergenic spacer (cpcBA–IGS) and 16S–23S internal transcribed spacer (ITS). The aquatic habitat of the new material from ...

Cultural Characterization of Fungi Isolated From Oil Contaminated Soils

Abstract Application of Fungi for effective removal of hydrocarbon contamination from soil is being considered as the better option when it comes to biodegradation. Other method like physical and chemical bioremediation leads to production of toxic compounds and these methods are not cost effective. In the present study, soil samples from four different oil contaminated soils were assessed for any recovery of fungi present. Cultural characterization was used as preliminary identification usi...

Local management and landscape drivers of pollination and biological control services in a Kenyan agro-ecosystem

Abstract Arthropods that have a direct impact on crop production (i.e. pests, natural enemies and pollinators) can be influenced by both local farm management and the context within which the fields occur in the wider landscape. However, the contributions and spatial scales at which these drivers operate and interact are not fully understood, particularly in the developing world. The impact of both local management and landscape context on insect pollinators and natural enemy communities and...

Seagrass Removal Leads to Rapid Changes in Fauna and Loss of Carbon

Abstract Seagrass habitats are important natural carbon sinks, with an average of ∼14 kg C m−2 buried in their sediments. The fate of this carbon following seagrass removal or damage has major environmental implications but is poorly understood. Using a removal experiment lasting 18 months at Gazi Bay, Kenya, we investigated the impacts of seagrass loss on sediment topography, hydrodynamics, faunal community structure and carbon dynamics. Sediment pins were used to monitor surface elevat...

Drought Response in Selected Tropical Inbred Maize Lines and Relative Expression of PARP2 Gene under Limited Water Conditions

Abstract Drought is the leading single factor that limits maize production thus inhibiting the crops genetic potential. In response to drought, maize and other plants synthesize Poly ADP-Ribose (PAR) protein. This process is controlled by the Poly ADP-Ribose Polymerase (PARP) genes and consumes cellular energy, leading to plant death. This study evaluated four tropical inbred maize (Zea mays L.) lines; CML 216, CML 144, A04 and E04 for their response to growth limiting water stress and their...

Carbon in the Coastal Seascape: How Interactions Between Mangrove Forests, Seagrass Meadows and Tidal Marshes Influence Carbon Storage

Abstract Purpose of Review We use the ‘seascape’ concept to explore how interactions between mangrove forests, tidal marshes and seagrass influence the storage of carbon in these ecosystems. Mangrove forests, with the other two ‘blue carbon’ habitats, are exceptionally powerful carbon sinks. Maintaining and enhancing these sinks is an emerging priority in climate change mitigation. However, managing any one ecosystem on its own risks is ignoring important contextual drivers of carbon...

Soil fertility dynamics in Bambara groundnuts (Vigna Subterranea) and Nerica rice (Oryza Sativa) intercrop system in small holder farms in Western Kenya.

Abstract/Overview Agricultural production in Kenya has stagnated since 1980s resulting in malnutrition in over 89% of Kenya’s population. Food insecurity has been identified as the prime cause of malnutrition. Low agricultural productivity due to declining soil fertile from poor cropping systems and use of non adapted exotic crop species has worsened this situation. Intercropping offers advantages if well planned including improved soil fertility and yields. Bambara groundnuts have show...

Characterization of the late embryogenesis abundant (LEA) proteins family and their role in drought stress tolerance in upland cotton

Abstract/Overview Background: Late embryogenesis abundant (LEA) proteins are large groups of hydrophilic proteins with major role in drought and other abiotic stresses tolerance in plants. In-depth study and characterization of LEA protein families have been carried out in other plants, but not in upland cotton. The main aim of this research work was to characterize the late embryogenesis abundant (LEA) protein families and to carry out gene expression analysis to determine their potentia...

Nematode diversity and its association with soil properties in monocrop pigeon pea

Abstract Pigeon pea is a versatile pulse crop grown in semi-arid regions of Kenya; however, its production is affected by plant-parasitic nematodes. The current study was undertaken to investigate the diversity of nematodes and the influence of soil properties on their diversity in monocrop pigeon pea fields in Mbeere North, Embu County, Kenya. Soil samples were collected from Gatunguru B, Gwakaithi, Itururi, Kambungu, Kanyueri, Karigiri, Mbangua and Njarange regions. From each field, soil s...

Potential for the establishment of Cylas punticollis Boheman (Coleoptera: Apionidae) as a pest of sweetpotato in Lesotho

Abstract: Sweetpotato, Ipomoea batatas (L.) Lamarck was introduced into Lesotho in 1992 in the hope that it would help alleviate poverty levels. Efforts are being made to learn the potential constraints to optimal production of this crop. Insect pests especially the sweetpotato weevils, Cylas species are a major production constraint worldwide. Hence the main objective of the study was to predict if these pests have potential to establish themselves in Lesotho. Two Cylas species, C. formicar...

Biological studies on the lepidopteran egg parasitoid Trichogrammatoidea lutea Girault (Hymenoptera : Trichogrammatoidae) at various temperatures

Abstract: The African bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), is a polyphagous pest that attacks many crops in sub-Saharan Africa. The pest is currently managed through chemical control, and by planting Bt-transgenic cotton. Trichogrammatoidea lutea Girault (Hymenoptera: Trichogrammatidae) is an indigenous egg parasitoid of H. armigera in southern Africa. The study was undertaken to determine the potential of T. lutea as a biological control agent for augmentative ...


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