Browsing by Autor "Claes Persson"

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Cinchona anderssonii (Rubiaceae), a new overlooked species from Bolivia
(Q15088586, 2017) Carla Maldonado; Claes Persson; Joaquina Albán Castillo; Alexandre Antonelli; Nina Rønsted
Cinchona anderssonii, a new species from the Yungas forests of the Andes in Bolivia, is described and illustrated. It is unique in Cinchona by having the combination of elliptic leaf blades glossy above, distinct circular pit domatia at secondary vein axils, basipetally dehiscent capsules, and relatively large seeds (8–11 mm long). A taxonomic key for the identification of the Cinchona species occurring in Bolivia is presented.
Estimating species diversity and distribution in the era of <scp>B</scp>ig <scp>D</scp>ata: to what extent can we trust public databases?
(Wiley, 2015) Carla Maldonado; Carlos I. Molina; Alexander Zizka; Claes Persson; Charlotte M. Taylor; Joaquina Albán Castillo; Eder Chilquillo; Nina Rønsted; Alexandre Antonelli
Open databases and integrative bioinformatic tools allow a rapid approximation of large-scale patterns of biodiversity across space and altitudinal ranges. We found that geographic inaccuracy affects diversity patterns more than taxonomic uncertainties, often leading to false positives, i.e. overestimating species richness in relatively species poor regions. Public databases for species distribution are valuable and should be more explored, but under scrutiny and validation by taxonomic experts. We suggest that database managers implement easy ways of community feedback on data quality.
Phylogeny Predicts the Quantity of Antimalarial Alkaloids within the Iconic Yellow Cinchona Bark (Rubiaceae: Cinchona calisaya)
(Frontiers Media, 2017) Carla Maldonado; Christopher J. Barnes; Claus Cornett; Else Holmfred; Steen Honoré Hansen; Claes Persson; Alexandre Antonelli; Nina Rønsted
Considerable inter- and intraspecific variation with respect to the quantity and composition of plant natural products exists. The processes that drive this variation remain largely unknown. Understanding which factors determine chemical diversity has the potential to shed light on plant defenses against herbivores and diseases and accelerate drug discovery. For centuries, Cinchona alkaloids were the primary treatment of malaria. Using Cinchona calisaya as a model, we generated genetic profiles of leaf samples from four plastid (trnL-F, matK, rps16, and ndhF) and one nuclear (ITS) DNA regions from twenty-two C. calisaya stands sampled in the Yungas region of Bolivia. Climatic and soil parameters were characterized and bark samples were analyzed for content of the four major alkaloids using HPLC-UV to explore the utility of evolutionary history (phylogeny) in determining variation within species of these compounds under natural conditions. A significant phylogenetic signal was found for the content of two out of four major Cinchona alkaloids (quinine and cinchonidine) and their total content. Climatic parameters, primarily driven by changing altitude, predicted 20.2% of the overall alkaloid variation, and geographical separation accounted for a further 9.7%. A clade of high alkaloid producing trees was identified that spanned a narrow range of altitudes, from 1,100 to 1,350 m. However, climate expressed by altitude was not a significant driver when accounting for phylogeny, suggesting that the chemical diversity is primarily driven by phylogeny. Comparisons of the relative effects of both environmental and genetic variability in determining plant chemical diversity have scarcely been performed at the genotypic level. In this study we demonstrate there is an essential need to do so if the extensive genotypic variation in plant biochemistry is to be fully understood.