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Lichens: Biodiversity and Biogeography. Conservation Biology.

  • Lichens are the best example of how the individuality of eukaryotes is composed, complex and multidimensional. New properties - nonlinear - emerge from the morphological and metabolic integration of symbiotic associations between very different organisms -symbiogenesis- that represent evolutionary innovations (Margulis & Auger 2003: BioScience 53 (8):776-778, 2004 Izco Auger in Botany .: 288-291). The lichen thalli are complex systems as identified from cyclic symbiosis between at least one mycobiont and photobiont (Chapman & Margulis 1998: . . Intl Microbiol 1:319-326 ) and exhibit great morphological, physiological and adaptive originality, so they are considered peculiar microecosystems, where there may be several types of photobionts.
  • Flora and taxonomy in: Europe, Mediterranean regions, Canary Islands, California, Arizona, Mexico , Baja California, Sonora Desert , Siberia, South China . Lichenicolous fungi: lichenized or not.
  • Conservation Biology. Lichens Diversity of The Muniellos Nature Reserve (Asturias), MAB Biosphere Reserve by UNESCO. Applications to space management and forestry handling. Lichen diversity indices, European Network of Environmental Quality. Designs in relation to the Forest Health Programme of the USDA Forest Service, USA. Biodiversity Heritage. Applications to natural areas management and handling forestry. Biosensing sustainable forest managements: The case of the pine forests of S ª Juárez in Oaxaca (Mexico).
  • Earthlings and stray. Saxicolous (deserts ↔ high mountains)
  • Epiphytes in ecosystems of: cork oak, holm oak, chestnut trees, beech, birch, hazel, alder and oak groves. Pine trees and sabinares albares (Spanish Juniper).
  • Monograph of the genus Acarospora, subgenus Xanthothallia in North America and Europe. Oxford University Press.
  • Analysis of symbiogenesis as a source of evolutionary innovation (morphogenetic and functional models). Self-organization, complex processes, mathematical models. In collaboration with M. De Renzi (ICBIBE)

Lichen photobionts: physiology, genomics and proteomics Trebouxia sp. pl.

  • Interdisciplinary Projects: UAH: Plant Physiology; URJC: Conservation and Biodiversity, UPV: agroforestry ecosystems; Missouri University- USDA Plant Genetics Research Unit. It aims to contribute to the knowledge of the morphological, genetic and functional diversity of lichen photobionts both isolated and propagated in axenic and in symbiosis (petals).
  • The photobionts, Trebouxia sp. pl, in symbiosis or in culture, undergo cycles of dehydration/rehydration combined with other abiotic stress treatments: high and low temperatures, high irradiance, exposure to pollutants (SO2, O3, heavy metals). The responses are analyzed by: 1) modulated chlorophyll fluorescence techniques; 2) biochemical and enzymological techniques; 3) sequencing, and studying gene expression; 4) characterization of proteins involved in stress responses. 5) microscopic and ultrastructural techniques (MO, epifluorescence, TEM, and SCM LTSM, confocal). 6) production of ROS (oxidative stress ) by photobionts and emission of NO by mycobionts (defense).
  • Results: Isolation and propagation of axenic cultures of Ramalina farinacea photobionts (L. ) Ach. (model)
  • Structural Plans of thylakoids of chloroplasts lacking grana issues involving PSI and PSII interest and their evolutionary significance
  • The resistance to hydration processes/dehydration, vary the speed, temp, light intensity and periods of darkness. Some parameters of the fluorescence kinetics involved are different from those of plants.
  • Detection of Ndh complex (NADH dehydrogenase plastid) in Trebouxia sp. thalli of Ramalina farinacea and its absence in other species of the same genus. Phylogenetic implications.
  • Sequencing of the genes: rbcL, cPSA, psbA, petB, atpB, ndhD, ndhF and 23S rDNA partial. Detection of 7 group I introns, of which presence, number, placement and " splicing" may be used as diagnostic characters with isozyme patterns of superoxide dismutase ( SOD).
  • NO seems to play a crucial role in protecting against photooxidation of photobionts, which could be related to the origin of the symbiotic relationship with the fungus. The specific depletion of NO by air pollutants may be at the origin of the decline of populations of lichens affected.
  • It has been found that consortia non-photosynthetic bacteria (N-fixing?) Associated with the cortex, in Ramalina and Usnea, are common, and physical relationships between the mycobiont and bacteria are established. While most bacterial groups found in the outer zone of the cortex, can also be placed inside the cortical plecténquima but never reach the area of primary photobionts. We hypothesize that there are more types of interactions in lichens and new hypotheses on the role of these bacteria in the thalli.

Ecophysiology: Lichens, trees and agricultural crops

  • Environmental stresses: light, temperature, hydration/dehydration.
  • Kinetics of chlorophyll fluorescence (fluorometer, actinic light). Photosynthesis performance.
  • Xanthophyll pigments cycle analysis. Determination of ascorbate. Antioxidant enzymes activity. Lipid peroxidation of cell membranes.
  • Results: Terrestrial Adaptations poiquilohidros (lichens and bryophytes ) plants and erratic inputs of water, under high irradiation.
  • NPQ (non-photochemical dissipation) is the parameter that most stimulated during desiccation and freezing.
  • Pn is maximal at 65-80 % water content
  • Ascorbate and xanthophylls involved in the photoresist during cooling and desiccation.
  • Identification of genes of the complex plastid NADH: finding in some species of lichens and Trebouxia in crop plants. No species of conifers ( pines) . Morphoanatomical and physiological relationships.

Air Pollution Bioindication and Environmental Conditions

Field conditions (Lichens and pines)

  • Control Biological Networks and monitoring of air quality in large areas (passive monitoring). Valencian Community, Canary Islands, León, Madrid, Galicia, Italy, mountains of San Bernardino and Santa Barbara (California).
  • Transplants conducting (active monitoring).

Laboratory conditions:

  • Leaching of inorganic ions. In collaboration with Guillermo Ramis -Ramos, Analytical Chemistry, UVEG. (Needles, Lichens).
  • Fumigation with pollutants gases: O3, SO2 and NOx, in closed systems. (Lichens, Bryophytes).
  • Activity of antioxidant enzymes. Lichens and crop plants.
  • Identification of genes NADH: finding in lichen and algae crop plants. No species of conifers (pines). Two manuscripts submitted to international journals and several works being drafted.

Field and laboratory mixed conditions: Effects of air pollutants on agricultural crops

  • Spraying photooxidants: O3 in OTCs (open top chambers) with weather station (Exp Est Carcaixent, Department of Agriculture). Agricultural crops and pine.
  • Characterization of damage that ozone concentrations e observed in Valencia make to vegetables and citrus in general, and search for possible palliative. Study has continued, in collaboration with the CEAM (GVA), the ozone effects on endemic pine Islands, where for years we have quantified its effects on natural forests on the islands of Tenerife, La Palma, Gran Canaria and El Hierro.
  • From data processing experiments carried out in the years 1996-2006, it has been tested sensitive and commercial varieties of Valencian crops: physiological and morphological response is varied. They have resulted in numerous publications including differences in ozone sensitivity of some varieties of tomatoes, melons, watermelons, lettuce, potatoes, spinach, barley or orange. We have evaluated numerous physiological parameters have been characterized visible injury symptoms and productivity of fruits or tubers.
  • We have also studied some mechanisms of protection against photo-oxidative stress ozone and activity of some substances that protect crops "in situ".

Cork Quality Bioindication. (Lichens and character of trees)

  • Trees external characters. Predictive models: Lichens and physico-chemical parameters of the climate.
  • Anatomy and density of reproduction cork (physical properties). BIOPHOTONICS
  • Results: Numerous published papers, patents and book.

Cork: radial growth and density. PATENT

Authors: Barreno E & Fos S, Title: Procedimiento para la obtención de secciones delgadas del corcho de Quercus suber L., Registration No. : 2068156 A1, Head Entity: University of Valencia, Countries: EU and USA, International Classification GO1N 1/28, International Priority: from 07/28/93, Location: Boletín de la propiedad industrial, 01.04.95 No. 2592 p. 178