Aim The endangered Galápagos shrub snapdragon (Galvezia leucantha, Antirrhineae, Plantaginaceae) is restricted to small populations on four islands. In this study, we appraised results from taxonomy, genetics, phylogenetics, phylogeography and pollination ecology to reconstruct the evolutionary history of the genus Galvezia. Location Peru, continental Ecuador and Galápagos. Methods We sequenced the nuclear ribosomal ITS and two plastid regions, ndhF and ndhF‐rpL32, to infer the origin of Galvezia and patterns of colonization to and across the Galápagos archipelago, based on Bayesian inference and statistical parsimony analyses. To investigate genetic diversity and differentiation within G. leucantha, we screened the genome of six populations and obtained 194 AFLP fingerprints. Autogamy tests and pollination network analyses were performed to evaluate the colonization potential and to investigate the structure of the pollinators’ assemblage of Galvezia. Results Relationships of seven nucleotide‐substitution haplotypes and 11 nucleotide‐substitution ribotypes of Galvezia revealed monophyly for the Galapagos species. Dating estimates indicated divergence of the insular Galvezia lineage in the Middle‐Upper Pleistocene (0.66–0.09 Ma). In addition, distribution of genotypes (seven haplotypes, eight ribotypes) across the three continental species showed geographical differentiation, while low differentiation and distribution of G. leucantha. AFLP genetic diversity is relatively high (HT = 0.109), but a low proportion of the total allelic variance is attributed to variation among subspecies/islands (Hb = 0.035, hierarchical AMOVA: 3.77% of total variance). The endemic bee (Xylocopa darwinii) accounted for 87.30% of the floral visits to G. leucantha. Main conclusions We inferred a single origin for an insular lineage that colonized the Galápagos Islands from northern Peru in the Pleistocene. Recent colonization of the archipelago, Pleistocene land bridges between islands and active gene flow promoted by X. darwinii may account for the low‐moderate genetic differentiation of G. leucantha subspecies. An unusual pollination shift from ornithophily (hummingbirds on the continent) to entomophily (Xylocopa in the Galápagos Islands) is supported.
We describe a reproductive and population dynamic study of the total population of a Critically Endangered plant over 10 years, during which part of the population was protected from the main threat, feral ungulates. Linum cratericola (Linaceae) was first discovered in 1966 at two sites on Floreana Island, Galápagos. It has since disappeared from one site and survives in three groups of plants at the other, where it has been threatened with extinction by introduced ungulates and invasive plants. Population size, and growth rate and mortality of individual plants, have been monitored since 1997. The population appears highly responsive to changes in threat levels: the three plant groups increased rapidly following protection by fencing and ungulate control, but temporarily declined when feral goat pressure increased and during dry periods. Natural factors that may contribute to population limitation include dry years, grazing by native snails and competition from native vascular plants and cryptogams. Linum cratericola has a single flowering period per year and produces abundant seed with 28% germination after scarification, but with no obvious adaptations for long-distance dispersal. Potential pollinators included the butterfly Leptotes parrhasioides, the hoverfly Toxomerus crockeri and the carpenter bee Xylocopa darwinii, all endemic to Galápagos. The continued survival of L. cratericola in the wild depends on effective protection from introduced herbivores and invasive plants.
This study examined the leaves of Baccharis macrantha to obtain extracts of Baccharis macrantha (EBM) and to determine the total flavonoid content (TFC) and the total polyphenol content (TPC). The main objective of this work was to quantify TPC and TFC of extracts of B. macrantha from Ecuador and evaluate its antioxidant and anti-inflammatory activities and inhibition of lipid peroxidation. The extraction method was optimized with solvents, ethanol, and methanol, at temperatures of 30–60 °C and extraction times of 5–20 min. The optimal TFC extraction conditions were at EtOH25% at 50 °C for 10 min. The optimal TPC extraction conditions were at EtOH50% at 50 °C for 10 min. EBM was characterized by TLC and HPLC with three standards: gallic acid, catechin, and quercetin. EBM-EtOH25% and EBM-EtOH50% obtained at 50 °C for 10 min were used to identify quercetin and evaluate biologicals activities. Quercetin was detected in EBM (EtOH25% and EtOH50%). EBM anti-inflammatory activity was evaluated with the red blood cell stabilization (RBC) method. The RBC model showed values of 49.72% of protection lysis RBC to EBM-EtOH25% and 50.71% of protection lysis RBC to EBM-EtOH50%. The EBM in vitro inhibition of lipid peroxidation showed a protection of 77.00% (EtOH25%) and 73.11% (EtOH50%) when the TBARs method was used. EBM-EtOH25% and EtOH50% showed high antioxidant activity. EBM-EtOH25% presented values of ABTS (1172 µmol TE/g EBM), DPPH (836 µmol TE/g, EBM), and FRAP (85.70 µmol TE/g, EBM).
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