The complete mitogenome of an undescribed clam shrimp of the genus Gondwanalimnadia (Branchiopoda: Spinicaudata), from a temporary wetland in Central District, Botswana

Clam shrimps (Spinicaudata) are a widespread and diverse crustacean group that frequent temporary aquatic habitats, but few complete mitochondrial genomes have been published for this group. Here, we report the mitogenome of an undescribed Gondwanalimnadia species from Botswana. Raw sequences were assembled into a single circular genome with a total length of 15,663 bp. Thirteen protein-coding genes, 22 tRNAs, and 2 rRNAs were identified using the MITOS pipeline. The mitogenome’s GC content is 33.52%. Phylogenetic analysis using protein-coding genes confirmed that Gondwanalimnadia sp. is closely related to another member of the Limnadiidae, Limnadia lenticularis

Opportunities to improve goat production and food security in Botswana through forage nutrition and the use of supplemental feeds

Goats fulfil a central role in food and nutritional security across Africa with over half of households owning or rearing goats in rural areas. However, goat performance is poor and mortality high. This study assessed the nutritional quality of commonly used feeds and proposes feed-baskets to enhance goat nutrition and health. Feeds were collected from 11 areas within the Central District of Botswana, and macronutrient analyses were conducted, including crude protein, fibre fractions, ash, and metabolizable energy (ME). Forage nutrition was compared across seasons and soil types. Additionally, seasonal supplementation trials were conducted to evaluate consumption rates of various supplements, including crop residues, pellets, Lablab purpureus, and Dichrostachys cinerea. Each supplement was provided ad libitum for a 24-h period, and consumption rates determined. Findings revealed significant differences in nutrition among various feed sources, across seasons, and in relation to soil types (p < 0.001). Consumption rates of supplements were higher during the dry season, possibly due to reduced forage availability. Supplement consumption rates varied across supplement type, with crop residues accounting for approximately 1% of dry matter intake, compared to up to 45% for pellets, 13% for L. purpureus, and 15% for D. cinerea. While wet season feed baskets exhibited higher ME values compared to dry-season feed-baskets, the relative impact of supplementation was more pronounced during the dry season. These results highlight the potential for optimizing goat diets through improved grazing and browsing management, especially during the reduced nutritional availability in the dry season in Botswana. Such diet optimisation may improve goat health and productivity, which may positively impact the food and financial security of smallholders by providing both increased yields and increased resilience. Importantly, rural communities can experience some of the lowest food security levels in the region. The interventions explored in this study utilise natural capital, often freely available, which can be deployed through existing husbandry systems, potentially making them accessible and practical to smallholders

Thermal biology, population fluctuations and implications of temperature extremes for the management of two globally significant insect pests

CITATION: Nyamukondiwa, C. et al. 2013. Thermal biology, population fluctuations and implications of temperature extremes for the management of two globally significant insect pests. Journal of Insect Physiology, 59:1199-1211. doi:10.1016/j.jinsphys.2013.09.004The original publication is available at https://www.sciencedirect.com/journal/journal-of-insect-physiologyThe link between environmental temperature, physiological processes and population fluctuations is a significant aspect of insect pest management. Here, we explore how thermal biology affects the population abundance of two globally significant pest fruit fly species, Ceratitis capitata (medfly) and C. rosa (Natal fruit fly), including irradiated individuals and those expressing a temperature sensitive lethal (tsl) mutation that are used in the sterile insect technique. Results show that upper and lower lethal temperatures are seldom encountered at the field sites, while critical minimum temperatures for activity and lower developmental thresholds are crossed more frequently. Estimates of abundance revealed that C. capitata are active year-round, but abundance declines markedly during winter. Temporal autocorrelation of average fortnightly trap captures and of development time, estimated from an integrated model to calculate available degree days, show similar seasonal lags suggesting that population increases in early spring occur after sufficient degree-days have accumulated. By contrast, population collapses coincide tightly with increasing frequency of low temperature events that fall below critical minimum temperatures for activity. Individuals of C. capitata expressing the tsl mutation show greater critical thermal maxima and greater longevity under field conditions than reference individuals. Taken together, this evidence suggests that low temperatures limit populations in the Western Cape, South Africa and likely do so elsewhere. Increasing temperature extremes and warming climates generally may extend the season over which these species are active, and could increase abundance. The sterile insect technique may prove profitable as climates change given that laboratory-reared tsl flies have an advantage under warmer conditions.hortgro science, NRF, THRIP.https://www.sciencedirect.com/science/article/pii/S0022191013002060?via%3DihubPublisher’s versio

Global patterns in endemicity and vulnerability of soil fungi

Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high-resolution, long-read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West-Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land-cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early-diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms

Invasiveness, biology, ecology, and management of the fall armyworm, Spodoptera frugiperda.

First online

Preference of foraging ants (Hymenoptera: Formicidae) for bait toxicants in South African vineyards

Argentine ants Linepithema humile (Mayr), common pugnacious ants Anoplolepis custodiens (F. Smith) and cocktail ants Crematogaster peringueyi Emery are the main indirect ant pests in South African vineyards. These ants form mutualistic relationships with the vine mealybug Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae), an economic phloem-feeding pest of vines that excretes honeydew. Ants feed on the honeydew from mealybugs and also affect predator-prey interactions by protecting them from attack by natural enemies. This consequently reduces the efficacy of predators and parasitic Hymenoptera in controlling P. ficus. Current strategies for ant control are limited to the application of long term residual insecticides that are detrimental to the environment, labour intensive to apply and potentially disruptive to biological control. Here, we report on the development of an alternative method of ant control using baits which are likely to show delayed toxicity to these ant species. Field bait preference assessments were carried out during spring, summer and autumn in three vineyards of the Cape Winelands region, Republic of South Africa during 2007/08. Preference/non-preference is the first behaviour an ant exhibits when encountering bait and this was measured in terms of numbers of ants at bait stations. Five toxicants comprising Gourmet ant bait (containing 0.5% boric acid as active ingredient and a honeydew mimic as an attractant), boric acid (0.5%), fipronil (0.0001%), fenoxycarb (0.5%) and spinosad (0.01%) all dissolved in 25% sucrose solution were tested against a 25% sucrose solution control. Gourmet ant bait was overall the most preferred bait during spring, summer and autumn, and on some occasions being significantly more preferable to ants than the control solution. © 2011 Elsevier Ltd.Articl

Fitness costs of rapid cold-hardening in ceratitis capitata

AgriwetenskappeBewaringsekologie en EntomologiePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]

Mosquito community composition in Central District, Botswana: insights from a malaria endemic to non-endemic gradient

Spatial distribution of vector mosquitoes plays a critical role in the dynamics of associated diseases’ spread across diverse landscapes. In Botswana, six Districts are implicated as malaria endemic zones, one of which is the Central District comprising both malaria endemic and non-endemic sub-districts. Despite being the biggest in the country, mosquito diversity in this District is under-explored, more so in the malaria non-endemic sub-districts. Here, we thus sampled mosquito adults and larvae from the malaria endemic sub-district of Bobirwa and non-endemic sub-districts of Palapye and Serowe, to determine spatial mosquito abundance and diversity in the District. Overall, all the sub-districts had a representation of key mosquito taxa of medical and economic importance (Aedes, Culex and Anopheles), irrespective of malarial endemicity status. Bobirwa had the highest number of mosquitoes sampled (429) although the greatest species richness (0.8511) was observed from Palapye. Moreover, Palapye also recorded a species from another genus, Culiseta longiareolata, a known natural vector of avian malaria parasites. Given global climate shift projections for the region, there is a need for continuous area-wide surveillance for vector mosquitoes and associated parasites in curbing the risk of emerging and re-emerging infections. While the Anopheles-centric approach to mosquito control is still necessary, a holistic approach, incorporating other vector incriminated mosquito species is warranted, particularly given shifting climates and the presence of invasive disease associated vector mosquito species

Basal cold but not heat tolerance constrains plasticity among Drosophila species (Diptera: Drosophilidae)

Thermal tolerance and its plasticity are important for understanding ectotherm responses to climate change. However, it is unclear whether plasticity is traded-off at the expense of basal thermal tolerance and whether plasticity is subject to phylogenetic constraints. Here, we investigated associations between basal thermal tolerance and acute plasticity thereof in laboratory-reared adult males of eighteen Drosophila species at low and high temperatures. We determined the high and low temperatures where 90% of flies are killed (ULT90 and LLT90, respectively) and also the magnitude of plasticity of acute thermal pretreatments (i.e. rapid cold- and heat-hardening) using a standardized, species-specific approach for the induction of hardening responses. Regression analyses of survival variation were conducted in ordinary and phylogenetically informed approaches. Low-temperature pretreatments significantly improved LLT90 in all species tested except for D. pseudoobscura, D. mojavensis and D. borealis. High-temperature pretreatment only significantly increased ULT90 in D. melanogaster, D. simulans, D. pseudoobscura and D. persimilis. LLT90 was negatively correlated with low-temperature plasticity even after phylogeny was accounted for. No correlations were found between ULT90 and LLT90 or between ULT90 and rapid heat-hardening (RHH) in ordinary regression approaches. However, after phylogenetic adjustment, there was a positive correlation between ULT90 and RHH. These results suggest a trade-off between basal low-temperature tolerance and acute low-temperature plasticity, but at high temperatures, increased basal tolerance was accompanied by increased plasticity. Furthermore, high- and low-temperature tolerances and their plasticity are clearly decoupled. These results are of broad significance to understanding how organisms respond to changes in habitat temperature and the degree to which they can adjust thermal sensitivity. © 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.Articl