28 research outputs found
Bacterial diversity of field-caught mosquitoes, Aedes albopictus and Aedes aegypti, from different geographic regions of Madagascar.
peer reviewedSymbiotic bacteria are known to play important roles in the biology of insects, but
the current knowledge of bacterial communities associated with mosquitoes is very
limited and consequently their contribution to host behaviors is mostly unknown.
In this study, we explored the composition and diversity of mosquito-associated
bacteria in relation with mosquitoes’ habitats. Wild Aedes albopictus and Aedes
aegypti were collected in three different geographic regions of Madagascar.
Culturing methods and denaturing gradient gel electrophoresis (DGGE) and
sequencing of the rrs amplicons revealed that Proteobacteria and Firmicutes were
the major phyla. Isolated bacterial genera were dominated by Bacillus, followed by
Acinetobacter, Agrobacterium and Enterobacter. Common DGGE bands belonged to
Acinetobacter, Asaia, Delftia, Pseudomonas, Enterobacteriaceae and an uncultured
Gammaproteobacterium. Double infection by maternally inherited Wolbachia
pipientis prevailed in 98% of males (n = 272) and 99% of females (n = 413); few
individuals were found to be monoinfected withWolbachia wAlbB strain. Bacterial
diversity (Shannon–Weaver and Simpson indices) differed significantly per habitat
whereas evenness (Pielou index) was similar. Overall, the bacterial composition
and diversity were influenced both by the sex of individuals and by the environment
inhabited by the mosquitoes; the latter might be related to both the
vegetation and the animal host populations that Aedes used as food sources.‘Arthropod Symbioses: from fundamental to pest disease management’
Win-win opportunities combining high yields with high multi-taxa biodiversity in tropical agroforestry
Resolving ecological-economic trade-offs between biodiversity and yields is a key challenge when addressing the biodiversity crisis in tropical agricultural landscapes. Here, we focused on the relation between seven different taxa (trees, herbaceous plants, birds, amphibians, reptiles, butterflies, and ants) and yields in vanilla agroforests in Madagascar. Agroforests established in forests supported overall 23% fewer species and 47% fewer endemic species than old-growth forests, and 14% fewer endemic species than forest fragments. In contrast, agroforests established on fallows had overall 12% more species and 38% more endemic species than fallows. While yields increased with vanilla vine density and length, non-yield related variables largely determined biodiversity. Nonetheless, trade-offs existed between yields and butterflies as well as reptiles. Vanilla yields were generally unrelated to richness of trees, herbaceous plants, birds, amphibians, reptiles, and ants, opening up possibilities for conservation outside of protected areas and restoring degraded land to benefit farmers and biodiversity alike