Trinidad Ruiz Téllez

Chemical composition and antioxidant activity of the essential oil of Thymbra capitata (L.) Cav. in Spain

Abstract We studied the chemical composition of the essential oil of Spanish populations of Thymbra capitata. The production from different parts and their antioxidant capacity were compared both during flowering and during fruiting over three years, from wild and cultivated material. 38 components were identified: highlighting aromatic monoterpenes (carvacrol ≥ 66%; p-cymene, 7.39.2%), monocyclic monoterpenes (y-terpinene, 3.4–11.2%; α-terpinene, 0.3–2.0%), bicyclic monoterpenes (α-thujene, 0.9–2.0%; α-pinene, 0.7–1.4%, camphene, 0.2–0.9%), acyclic monoterpene (myrcene, 1.7–2.4%) and sesquiterpenes as (E)-caryophyllene (1.0–2.0%). A very high lipophilic antioxidant activity was measured with no significant differences between the flowering and fruiting stage.

Seed germination and risks of using the invasive plant Eichhornia crassipes (Mart.) Solms-Laub. (water hyacinth) for composting, ovine feeding and biogas production.

Abstract Water hyacinth (Eichhornia crassipes (Mart.) Solms-Laub.) is an invasive aquatic weed that has one of the highest growth indices of vascular plants, producing large amounts of biomass. Its use for composting, livestock feed and biogas production has been proposed as a management strategy for its control. The work presented here is an assessment of the potential spread of water hyacinth due to the release of seeds from the by-products of some of these manufacturing processes. We tested experimentally if the seeds were destroyed or did not lose germinability when they had passed through the gut of sheep, remained in compost piles or been used in biogas bioreactors. We made optical and electronic microscopic observations, and calculated retrieval and germination percentages of the seeds subjected to these treatments. After having passed through the gut of sheep, the anatomical organization of the seed was completely destroyed, only 30.50 ± 5.83% of the seeds were retrieved and the germinability was null (0 ± 0%). The biogas production and compost-treated seeds both had retrieval percentages of 100 ± 0% and germination values of 1.00 ± 0.57 and 3.50 ± 0.96% respectively, with several anatomical damages. The use for compost or biogas production as a management strategy to control this pest is not completely safe from an environmental perspective and the selected management option should focus on sheep fodder production.

Fluctuating Asymmetry of Leaves in Digitalis thapsi under Field and Common Garden Conditions

The degree of developmental instability has been hypothesized to reflect the level of environmental and genetic stress. However, levels of fluctuating asymmetry or other indicators of developmental instability are rarely measured in the same populations under field and common garden conditions, making it difficult to determine whether differences in asymmetry derived from field measurements are simply phenotypic or genetic in origin. We studied fluctuating asymmetry of leaves in three populations of Digitalis thapsi L. that differed dramatically in mean seed production under field conditions and when reared in a common garden. While absolute asymmetry decreased with leaf position, there was no position effect on relative asymmetry after adjustment for leaf width. Absolute and relative asymmetry did not differ between seedlings and mature plants in the greenhouse. There was no significant difference in absolute or relative asymmetry of leaves between plants grown in the greenhouse and in the field, although there was a significant \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape

Anatomical plasticity in species of Deschampsia P. Beauv. (Poaceae) in SW Europe (Iberian Peninsula)

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Aportación a la bioclimatología de Portugal

\end{document} environment interaction. The number of leaves and the maximum length and width of leaves of mature plants reared in the common garden differed among populations. Fluctuating asymmetry in leaves was not significantly correlated with any measure of vegetative growth or reproduction. These findings indicate that the effects of environmental conditions and selection may override the effects of inherent differences. Thus, conclusions about levels of developmental instability in different populations based on field studies may differ considerably from conclusions based on results from common garden experiments.

Ensayo de germación en endemismos ibéricos

Abstract We analyzed the essential oils of three cultivated thymes whose provenance was populations at the limit of their distribution in Spain. In the flowering stage, the Peninsular endemic Th. villosus subsp. lusitanicus has linalool (49.6%) as principal component, an evidence for the chemical polymorphism described for this taxon. For Th. caespititius, high values are obtained for α-terpineol (41.1%), confirming the chemical homogeneity in the Iberian Peninsula. The studied population of the Eurosiberian species Th. pulegioides, which is at its southern limit in the Iberian Peninsula, has as principal components γ-terpinene (31.7%), thymol (25.6%), p-cymene (16.4%), and carvacrol (3.5%), values which do not compare readily with the literature data. The chemical analyses performed for the fruiting stage are new. The only major differences with the flowering stage are found for Th. pulegioides.

The essential oil of the protected species: Thymus praecox ssp. penyalarensis

Summary The utility of leaf anatomy in the taxonomy of the genus Deschampsia is discussed. To this end, the inter-and intra-populational variability of this character is analyzed in the taxa of the genus which are represented in the Iberian Peninsula (Deschampsia cespitosa (L.) Beauv. s.l., D. setacea (Huds.) Hack, and D. flexuosa (L.) Trin.), as well as in Holcus grandiflorus Boiss. and H. caespitosus Boiss., two Spanish endemic species which some authors include in Deschampsia. A critical analysis of their observed anatomical plasticity is given, evidencing the great intra-individual variability when wild plants are grown under experimental conditions.