Biology subjects

Brodschneider, R.

Publications and source records attributed to Brodschneider, R..

3 recordsLinked to original sources

bioRxiv2024

Managed honey bee colony losses and causes during the active beekeeping season 2022/2023 in nine Sub-Saharan African countries

This study reports for the first-time managed honey bee colony loss rates and associated risk factors during the active beekeeping season 2022/2023 in nine Sub-Saharan African countries, namely Kenya, Ethiopia, Rwanda, Uganda, Benin, Liberia, Nigeria, Cameroon and Democratic Republic of the Congo. The sustainability of bee swarm catches as a main honey bee colony source tool for operation expansion by African beekeepers was also evaluated in Kenya and Ethiopia. In this survey, the 1,786 interviewed beekeepers across these countries collectively managing 41,761 colonies registered an overall loss rate of 21.3%, which varied significantly among countries (from 9.7 to 45.3%) and hive types (from 10.6% in hives with movable frames to 17.9% in frameless hives). The perceived causes of losses in order of significance were issues beyond the beekeepers control (mainly theft, drought, and bushfire), absconding and pests (mainly wax moth, small and large hive beetles, ants and Varroa destructor mite), but this pattern varied greatly across countries. Among the management practices and characteristics, migratory operations and professional beekeepers experienced lower losses than stationary operations and semi-professionals and hobby beekeepers. Insights into the number of bee swarms caught revealed significant decreases in swarm availability over the past three years in Kenya. The opposite situation was observed in some regions of Ethiopia. These trends require further investigation. Overall, this comprehensive survey sheds light on the complexities and challenges beekeepers faced in Sub-Saharan Africa, pointing to the need for targeted interventions and sustained research to support the resilience and growth of the apicultural sector.

zoology↗

bioRxiv2023

Does sex influence element accumulation in honey bees: workers vs drones

Honey bees are social insects that have divided their work. Bees have two sexes, male and female. Female honey bees are queens and worker bees, while males are called drones. Worker bees have different tasks in the hive including gathering of food, its processing, caring for brood, protecting the hive, produce wax, nourish workers, drones and queen. Drones are male bees whose only role is to mate with a virgin queen. Many studies have dealt with physiology, behavior, morphology of workers and drones. This is the first study that compared differences in element accumulation and composition between workers and drones honey bees. It was observed that worker honey bees have higher concentration, from 116 % to 517 %, of most elements analyzed. Drones had higher concentration of essential elements to bees, Na, Mg, P, S, K, Zn, Cu and especially Se which was 2.2-fold higher. These differences can be attributed to environmental exposure; reproductive role of drones, high Se in sperm; but mostly to the food workers and drones eat. Worker bees feed on unprocessed food, mostly pollen, which is rich in minerals. Drones are fed by worker bees pre-processed food. Here we show that worker honey bees have a filtering mechanism that enables them to accumulate non-essential elements and not pass them on through the processed food to drones or larva.

physiology↗

bioRxiv2023

Semi-automated curation and manual addition of sequences to build reliable and extensive reference databases for ITS2 vascular plant DNA (meta-)barcoding

With the breakthrough of DNA (meta)-barcoding, it soon became clear that one of the most critical steps for accurate taxonomic identification is to have an accurate DNA reference database for the DNA barcode marker of choice. Therefore, developing such a database has been a long-term ambition, especially in the Viridiplantae kingdom. Typically, reference databases are constructed from marker sequences downloaded from general public databases, which can carry taxonomic and other relevant errors. Herein, we constructed a curated (i) global database, (ii) European crop database, and (iii) 27 databases for the EU countries for the ITS2 barcoding marker of vascular plants. To that end, we first developed a pipeline script that entails (i) an automated curation stage comprising five filters, (ii) manual taxonomic correction for misclassified taxa, and (iii) manual addition of newly sequenced species. The pipeline allows easy updating of the curated global database. With this approach, 13% of the sequences, corresponding to 7% of species, originally imported from GenBank were discarded. Further, 259 sequences were newly added to the curated global database, which now comprises 307,977 sequences of 111,382 plant species.

bioinformatics↗