Natural Resources Institute

Cassava brown streak disease (CBSD), caused by cassava brown streak virus (CBSV; Ipomovirus brunusmanihotis) and Ugandan cassava brown streak virus (UCBSV; Ipomovirus manihotis) (family Potyviridae, genus Ipomovirus), is increasingly becoming a threat to cassava production in several parts of Africa, especially in Eastern, Central and Southern Africa. In Kenya, the disease continues to wreak havoc on cassava production leading to a significant reduction in crop yields and economic losses of up to USD 1 billion. Variation in virus populations make the control of CBSD challenging as virus genomic variation can affect the accuracy of diagnostic tests, lead to resistance breaking isolates and jeopardize strategies of breeding for resistance. CBSV and UCBSV populations obtained from cassava fields in Kenya were characterized. In total, 44 new complete sequences of CBSV and UCBSV were assembled and 40 sequences successfully submitted to GenBank. Single Nucleotide Polymorphism (SNP) analysis revealed that the cylindrical inclusion protein (CI) is the most stable region across the genome of CBSV and UCBSV. In contrast, protein 1 (PI) and the coat protein (CP) were the most hypervariable regions. Phylogenetic analysis showed three major geographical groupings for both UCBSV and CBSV isolates, suggesting a continued spread of the viruses through human-mediated movement of infected planting materials. The data obtained in this study can support the development of disease management strategies through improved molecular diagnostic tests and targets for breeding for resistance against CBSD.

Noisy environments tend to mask sounds and disrupt animal behaviour. One of the most common responses from many animal species to noise is leaving or avoiding the noisiest parts of their ranges. Individuals may alter their movement patterns, either rapidly moving away or changing routes in response to increased noise levels. Here, we tested whether urban-dwelling pied tamarins (Saguinus bicolor): (1) preferentially used quieter areas within their home range, (2) increase travel speed, and (3) alter routes to avoid noise levels. To achieve this, we followed nine pied tamarin groups in five forest fragments within the city of Manaus, Brazil, recording their locations and levels of associated ambient noise levels. We also estimated fruit availability at random points within the group’s home ranges. We found that pied tamarins use the quieter areas of their ranges more intensively, but only if the fruit availability is high. Furthermore, groups did not increase their travel speed or change turning angles in response to noise alone, but travel speed increase in noisier areas closer to the border of their home ranges. Thus, pied tamarins do seem to use the quieter areas of their home ranges, but do not hurry to reach them unless their location lies closer to their home range borders. This may occur because higher noise levels at home-range borders could diminish intergroup communication effectiveness. In general, we found that pied tamarin’s use of space and movement patterns are soundscape-related but mediated by resource availability and social aspects.

Abstract Cultivated meat has undeniable potential to address some of the current detrimental impacts of animal farming, while addressing food security worldwide. However, one of the main challenges in cultivated meat production is manufacturing cost. The main contributor to cost is the culture media which comprises expensive components such as growth factors and animal-derived proteins. This study investigated alternative, food grade, high protein extracts as serum replacements in serum-free media formulations. The extracts were chosen to represent various sustainable sources of proteins: marine (spirulina e.g. cyanobacterium), plant (faba bean) and insect (mealworm flour). Different processing methods and different solvents were investigated for production of cell culture-compatible extracts which were then tested with mouse myoblasts (C2C12) and primary porcine myosatellites (pMyoSCs). A serum-free medium formulation containing 2.6% v/v spirulina extract was found to support long term growth of C2C12 cells for ∼10 population doublings compared to only ∼2 in the control. The processing steps were optimized, showing that a glycerine solution was best for free amino acid and protein yield (4950 µM total free amino acids, 11.45 mg/mL protein concentration). This solution had a positive effect on C2C12 cells, increasing their growth by up to 20% when added to the B8 medium. However, this benefit did not translate to pMyoSCs, which showed no significant growth increases in short-term screening. This work demonstrates a method for converting food grade protein powders into effective culture media supplements and highlights the potential of spirulina-based extracts for the use in cultivated meat. Abstract Figure Graphical abstract Created in BioRender. Gordon-Petrovskii, W. (2025) https://BioRender.com/by7khs1

Glandular defensive systems remain poorly understood in many marine invertebrates. Here, we investigated the anatomy and chemical composition of mantle-margin glands in the true limpet Tectura virginea. These glands produce a persistent, thread-like secretion that emerges from the exposed mantle edge in response to mechanical stimulation. Light and electron microscopy revealed large glands, each dominated by a single voluminous secretory cell surrounded by quiescent precursors and ring musculature, suggesting a holocrine expulsion mechanism. Liquid chromatography-mass spectrometry identified over 80 compounds, including disulfides, sulfonates and organic acids. Their presence suggests that the secretion may act as a chemical barrier against microbial colonization or small invertebrate predators. Several major compounds, such as 1-(propyldisulfanyl)-1-(propylsulfinyl)propane, have potential defensive roles. The anatomical position of the glands and the biochemical diversity of their products suggest a defensive role. Our findings support the interpretation of these mantle-margin glands as a novel repugnatorial system, representing a unique adaptation among patellogastropods. These findings highlight the potential for secretory and defensive functions in the mantle-margin glands of T. virginea, underscoring the broader relevance of such glands in less-studied lineages.

The bipartite begomovirus Tomato leaf curl New Delhi virus (ToLCNDV) causes major losses in solanaceous and cucurbit crops, yet strains differ in their ability to infect tomato and in virulence. To identify viral factors controlling host specificity a

ABSTRACT The Amazonian primate Chiropotes albinasus (red‐nosed cuxiu) is a specialist on seeds of hard‐husked unripe fruit. These are accessed with specialized processing behavior, involving highly modified canines and incisors. This is energetically demanding and carries a high dental damage risk. Hypothesizing that red‐nosed cuxiu process foods in ways that minimize both energetic expenditure and maximize dental safety, we predicted that individuals would selectively bite fruit husks at locations that were easiest to penetrate. Sutures were the easiest area to penetrate for all the 11 analyzed red‐nosed cuxiu diet species with functioning (non‐fused) sutures. Quantification of bite mark locations on these fruits showed significant clustering along the lower‐penetrability areas (sutures) in 8 of 11 species (72.7%). This pattern did not exist for another 10 species that lacked sutures; bites did not cluster on the thinnest (and most easily penetrated) parts of the husk for 9 of these 10 species (90%). For four species that were functionally indehiscent due to fused or thick sutures, penetrability was lowest at the face (2 species) and suture (2 species). Thus, despite robust crania, mandibles, and dentition that appear highly suited for resisting forces generated by powerful biting action, red‐nosed cuxiu deploy a more refined technique and often select the weakest areas of fruits for their seed‐accessing bite sites, especially when the fruits are dehiscent with unfused sutures.

IntroductionNourishing the growing and changing global population within sustainable limits is a pressing concern that must be addressed by 2030. To meet this challenge, it is argued food systems must transform, but a range of different food system configurations and trade-offs must be considered by national, regional and global decision-makers. Wild caught Small Pelagic Fish Species (SPFS) are a valuable source of human nutrition and are also frequently processed into fish meal and fish oil to become the principal protein and lipid sources for farmed animal feeds. The choices between the primary (i.e., for direct human consumption) and secondary (i.e., for animal feed ingredients) uses of small-pelagic freshwater and marine fish provides an illustrative example of contention and opportunity in balancing livelihood, income, consumer demand and human nutrition needs. Whilst the potential trade-offs have received much popular attention, there is a clear need to examine the evidence.MethodsIn this paper, we systematically collate peer reviewed literature and trade data from the African Great Lakes Region (AGLR) and the western coastal region of sub-Saharan Africa. A total of 201 articles met our search criteria, and of those we deemed 32 to hold sufficient and quality data for use in this review.ResultsThe AGLR (76%), and specifically Kenya (64%), were best represented in the literature which covered alternative feed proteins, assessment of feed/food nutritional quality and availability of feed/food resources. We find that the use of SPFS as feed limits access for use as food. This further supports innovations to develop fish oil and fish meal alternatives to safeguard SPFS for direct human consumption, particularly in resource-poor contexts.DiscussionSince most extracted evidence in this review was from the AGLR, there is still a need for more targeted investments for robust research that is cross-regional to better understand the magnitude, dynamics and trade-offs concerning the utilization of SPFS in SSA.

Biochar is a carbonized biomass that is used for soil amendment. Since 60% of the population in South Asia depends on agriculture, the negative consequences of soil degradation in this region significantly impact agricultural productivity, food security, and livelihoods. While several empirical studies have been conducted on the application of biochar in agriculture, no systematic reviews have been conducted in the South Asian context, leaving an evidence gap on biochar application in agriculture. This scoping review includes a total of 26 studies published between the years 2015 and 2023 for full-text analysis and evidence synthesis. Most studies were conducted in Pakistan, followed by Nepal, Bangladesh, and Sri Lanka. However, no studies were found in Afghanistan and the Maldives. Mostly, biochar was made by using the slow pyrolysis method. Randomised Controlled Trial (RCT) was the most common method to assess the effects of biochar on soil health and agricultural productivity. The review demonstrates that application of biochar with organic manure was more effective in improving soil properties, increasing carbon sequestration, and increasing crop yield than amendments with chemical fertilizers, biochar alone, or no application of biochar. Nevertheless, soil properties and yield effects were found to vary with soil type or feedstocks used for biochar production. This review concludes that further research should focus on the long-term application of biochar, which should be done over multiple cropping seasons and crop types.