Responses of evergreen and deciduous Quercus species to enhanced ozone levels

Plants of one evergreen oak (Quercus ilex) and three deciduous oaks (Q. faginea, with small leaves; Q. pyrenaica and Q. robur, with large leaves) were exposed both to filtered air and to enhanced ozone levels in Open-Top Chambers. Q. faginea and Q. pyrenaica were studied for the first time. Based on visible injury, gas exchange, chlorophyll content and biomass responses, Q. pyrenaica was the most sensitive species, and Q. ilex was the most tolerant, followed by Q. faginea. Functional leaf traits of the species were related to differences in sensitivity, while accumulated ozone flux via stomata (POD1.6) partly contributed to the observed differences. For risk assessment of Mediterranean vegetation, the diversity of responses detected in this study should be taken into account, applying appropriate critical levels. © 2010 Elsevier Ltd. All rights reserved.We thank both the Ministerio de Medio Ambiente y Medio Rural y Maritimo (in collaboration with ICP-Forests), and the Conselleria de Medi Ambient, Aigua i Habitatge and Interreg III (ForMedOzone and VegetPollOzone projects) for supporting the OTC activity. Institut Universitario CEAM-UMH is also supported by Generalitat Valenciana and Fundacion Bancaja, benefiting from CONSOLIDER-INGENIO 2010 (GRACCIE) and Prometeo (Generalitat Valenciana) Programs. Filippo Bussotti and two anonymous referees are thanked for their useful comments. Carmen Martin is also thanked for taking care of the plants.Calatayud, V.; Cervero, J.; Calvo, E.; García Breijo, FJ.; Reig Armiñana, J.; Sanz, M. (2011). Responses of evergreen and deciduous Quercus species to enhanced ozone levels. Environmental Pollution. 159(1):55-63. doi:10.1016/j.envpol.2010.09.024S5563159

Physiological,anatomical and biomass partitioning responses to ozone in the Mediterranean endemic plant Lamottea dianae

Ozone effects on the perennial forb Lamottea dianae were studied in an open-top chamber experiment. Ozone was found to induce reductions in CO 2 assimilation and water use efficiency in the leaves of this species. These reductions were mainly related to a decline in the in vivo CO 2 fixation capacity of Rubisco (V c,max), rather than to stomatal limitations or photoinhibitory damage (F v:F m). In addition to chloroplast degeneration, other observed effects were callose accumulation, formation of pectinaceous wart-like cell wall exudates and phloem alterations. Moreover, ozone exposure significantly reduced root dry biomass. The possible relevance of these adverse effects for Mediterranean forbs is commented. These results show that endemic plants can be very sensitive to ozone, suggesting that risks associated with this pollutant should be taken into account for conservation purposes. © 2011 Elsevier Inc.We thank the Conselleria de Medi Ambient, Aigua, territory i Habitatge and FEDER funds (project VegetPollOzone, Interreg IIIb, Meddoc) for supporting parts of this study. The Instituto Universitario CEAM-UMH is partly supported by Generalitat Valenciana, Fundacion Bancaja, and benefits form the projects CONSOLIDER-INGENIO 2010 (GRACCIE) and Prometeo Program (Generalitat Valenciana). Emilio Laguna and Mari Carmen Escriva are also thanked for providing us the plants and, together with Joan Perez, for their comments on aspects of the biology of this species. Carmen Martin is thanked for taking care of the plants. Four anonymous referees provided very useful comments for improving the manuscript.Calatayud, V.; García Breijo, FJ.; Cervero, J.; Reig Armiñana, J.; Sanz Sánchez, MJ. (2011). Physiological,anatomical and biomass partitioning responses to ozone in the Mediterranean endemic plant Lamottea dianae. Ecotoxicology and Environmental Safety. 74(5):1131-1138. doi:10.1016/j.ecoenv.2011.02.023S1131113874

Agronomic treatments to avoid seed presence in `Nadorcott¿ mandarin I. Effect on in vivo pollen tube growth

[EN] Fresh market demands high quality fruit and, therefore, citrus growers and researchers are constantly looking for solutions to avoid seed presence. Current horticultural techniques have low effectiveness or high cost. The objective of this study is to evaluate the inhibition effect of seven products on the in vivo pollen tube growth in Nadorcott mandarin, which is a high-value seedy variety. To achieve this main objective, three inorganic fer­ tilizers (ammonium nitrate, potassium nitrate, sulfur), and four saccharides (saccharose, methyl cellulose, cal­ lose, chitosan) were applied to Nadorcott stigmas 24 h before and after hand pollination. Pollen tubes were counted 1, 3, and 5 days after treatment in longitudinal blue violet autofluorescence-stained sections. Of the seven evaluated products, only sulfur had a strong inhibitory effect. Elemental sulfur (S 8 ) inhibited pollen tube growth by 94-100%. This strong effect was observed regardless of sulfur being applied 24 h before or after pollination, and on fixed flowers 1, 3 or 5 days after applications. Saccharose treatment seemed to have the opposite effect: stimulated pollen tube growth, but the difference with the positive control was small and non- significant. The sulfur effect could be useful for designing agronomic applications capable of preventing seed presence in Nadorcott mandarin.This research was supported by the Asociación Club de Variedades Vegetales Protegidas as part of a project undertaken with the Universitat Politècnica de València (Spain, UPV 20170087), of which H. Merle was the principal researcher. There was no additional external funding received for this study.Garmendia, A.; García-Breijo, F.; Reig, J.; Raigón Jiménez, MD.; Beltrán, R.; Zornoza, C.; Cebrián, N.... (2022). Agronomic treatments to avoid seed presence in `Nadorcott¿ mandarin I. Effect on in vivo pollen tube growth. Scientia Horticulturae. 294:1-10. https://doi.org/10.1016/j.scienta.2021.11076011029

Morphology, anatomy and germination response of heteromorphic achenes of Anthemis chrysantha J. Gay (Asteraceae), a critically endangered species

[EN] This study demonstrates that Anthemis chrysantha, a 'Critically Endangered' annual plant, produces two morphs of achenes: white and dark achenes, which differ in size, mass, anatomy and germination behaviour. Fresh white achenes germinated at all temperatures assayed from 10 to 25 degrees C in both continuous darkness and 12-h photoperiod, ranging between 24% at 25 degrees C in darkness and 89% at 12/20 degrees C in light, whereas fresh dark achenes did not germinate under any temperature or light conditions. To identify differences in dormancy type between the two morphs, germination of dry-stored achenes, and achenes stratified at 5 or 25 degrees C for 2 months were tested in both darkness and light at 5, 15 and 12/20 degrees C for dry-stored and warm-stratified (25 degrees C) achenes; and at 15, 25 and 12/20 degrees C for cold-stratified (5 degrees C) achenes. Of the white achenes, 90% germinated during the cold stratification period. In general, dry storage and warm stratification did not increase germination compared to fresh achenes. However, dark achenes did not germinate under any conditions. Dark achene dormancy was only broken by mechanical scarification or by excising the embryo (germination reached 71%). An anatomical study showed that the mesocarp of dark achenes had no intercellular spaces and was much thicker and stronger than that of white achenes, making the entry of water difficult, and also preventing germination by mechanical restriction. This study demonstrated that dormancy in the dark achenes is likely caused by the thickness of their pericarp, physically impeding germination and hampering imbibition of water.This work was financed by the Consejeria de Agricultura y Agua de la Comunidad Autonoma de la Region de Murcia and the Fundacion Seneca de la Region de Murcia (Project 1186/PI/09).Aguado, M.; Martinez-Sanchez, JJ.; Reig Armiñana, J.; García Breijo, FJ.; Franco, JA.; Vicente, MJ. (2011). Morphology, anatomy and germination response of heteromorphic achenes of Anthemis chrysantha J. Gay (Asteraceae), a critically endangered species. Seed Science Research. 21(4):283-294. doi:10.1017/S0960258511000183S28329421

Coordinated ultrastructural and phylogenomic analyses shed light on the hidden phycobiont diversity of Trebouxia microalgae in Ramalina fraxinea

[EN] The precise boundary delineations between taxa in symbiotic associations are very important for evolutionary and ecophysiological studies. Growing evidence indicates that in many cases, the use of either morphological characters or molecular markers results in diversity underestimation. In lichen symbioses. Trebouxia is the most common genus of lichen phycobionts, however, the diversity within this genus has been poorly studied and as such there is no clear species concept. This study constitutes a multifaceted approach incorporating aspects of ultrastructural characterization by TEM and phylogenomics to evaluate the morphological and genetic diversity of phycobionts within the sexually reproducing lichen Ramalina fraxinea in the context of Mediterranean and temperate populations. Results reveal an association with at least seven different Trebouxia lineages belonging to at least two species. T. decolorans and T. jamesii, and diverse combinations of such lineages coexisting within the same thallus depending on the analysed sample. Some of these lineages are shared by several other non-related lichen taxa. Our findings indicate the existence of a highly diverse assemblage of Trebouxia algae associating with R. fraxinea and suggest a possible incipient speciation within T. decolorans rendering a number of lineages or even actual species. This study stresses the importance of coordinated ultrastructural and molecular analyses to improve estimates of diversity and reveal the coexistence of more than one Trebouxia species within the same thallus. lt is also necessary to have clearer species delimitation criteria within the genus Trebouxia and microalgae in general.This study was funded by the Ministerio de Economia y Competitividad (MINECO CGL2012-40058-0O2-01/02), FEDER, the Generalitat Valenciana (PROMETEOII2013/021, GVA) and the Direccion General de Universidades e Investigacion de la Consejeria de Educacion de la Comunidad de Madrid - Universidad de Alcala (CCG10-UAH/GEN-5904). Drs. Arantxa Matins and Patricia Moya (Universitat de Valencia) made helpful comments on the manuscript.Català, S.; Campo, ED.; Barreno, E.; García-Breijo, F.; Reig Armiñana, J.; Casano, L. (2016). Coordinated ultrastructural and phylogenomic analyses shed light on the hidden phycobiont diversity of Trebouxia microalgae in Ramalina fraxinea. Molecular Phylogenetics and Evolution. 94:765-777. https://doi.org/10.1016/j.ympev.2015.10.021S7657779

Epicuticular wax content and morphology as related to ethylene and storage performance of ‘Navelate’ orange fruit

8 pages, 6 figures, 1 table. -- Available online 15 September 2009.The effect of ethylene (2 μL L−1) on total and soft epicuticular wax content and wax morphology has been investigated in mature ‘Navelate’ (Citrus sinensis, L. Osbeck) oranges held under non-stressful environmental conditions (22 °C and constant high relative humidity (90–95% RH)). In addition, the objective of the study was to understand whether the ethylene-induced changes in epicuticular wax might participate in the beneficial effect of ethylene reducing non-chilling peel pitting, by modifying peel water, osmotic or turgor potential, or disease incidence caused by Penicillium digitatum (Pers.:Fr.) Sacc. Ethylene increased total and soft epicuticular wax content in ‘Navelate’ fruit and induced structural changes in surface wax that might be related to the formation of new waxes. Changes in epicuticular wax morphology, but not in its content, might be involved in the protective role of ethylene reducing non-chilling peel pitting, although the beneficial effect of the hormone is not related to water stress. Cell water and turgor potentials in freshly harvested fruit and fruit stored in air under non-stressful conditions suggest that water stress is not a limiting factor leading to the development of this physiological disorder. In addition, the results indicated that formation of new waxes in fruit treated with ethylene may partially cover stomata, cracks or areas lacking wax occurring in stored fruit and is likely to improve physical barriers to P. digitatum penetration.This work was supported by research grant AGL2002-1727 from the Comisión Interministerial de Ciencia y Tecnología (CICYT), Spain. Cajuste was the recipient of a fellowship from the Program SUPERA, México.Peer reviewe

La evolución de la simbiosis micorrícica

[ES] El presente trabajo comenta la importancia de la relación entre plantas terrestres y bongos, describe brevcmente los distintos tipos de micorrizas que han ido coevolucionando can las plantas y muestra ejemplos de los diferentes tipos de micorrizas observados en cortes histológicos de raíces de vegetales, tanto primitivos, como es el caso de los helechos, como mas evolucionados las orquideas).[EN] The present word co mments the importance of the relationship between terrestrial plants and fungi, it also describes briefly the diffcren t types of mycorrhzae wich have been coevoling with the plants and shows examples of the different types of mycorrhizae observed in histological cutting of vegetal roots both primitive Gust like the case of ferns) and those more evolved (orchids).García-Breijo, F.; Reig Armiñana, J.; Ibars Almonacil, A.; Estrellés, E. (2002). La evolución de la simbiosis micorrícica. Butlletí Societat Micològica Valenciana. (7):49-54. http://hdl.handle.net/10251/104810S4954

Aproximación al estudio anatomo histológico de la micorriza de Ophioglossum lusitanicum L

[ES] Se describen, desde el punto de vista histológico, los diversos organos de 0. lusitanicum L., especie recientemente citada en la Comunidad Valenciana, y se hace especial hincapié en el estudio de su micorriza, que aparece claramente visible en sus raices )' que se ha identificado como un Zigomicete vesiculo - arbuscular. Este tipo de estudios son necesarios para abordar los procesos de conservacion de esta especie y reintroduccio n de la misma en los diferentes eco,istemas, ya que la micorrizacion es necesaria para ]a obtención de ejemplares a partir de esporas.[EN] Several organs of Ophhioglossum Lusitanicum L., a species recently found in the Valencian Community, are described here from histological point of view. Special emphasis was given to the study of its mycorrhizae that appears clearly visible in its roots. It was identified Vesiculararbuscular Zygomycete. Is necessary to approach this type of study to processes of conservation and reintroduction of this species in different ecosystems, since the mycorrhization is necessary to obtain specimens germinated from spores.Reig Armiñana, J.; García-Breijo, F.; Ibars Almonacil, A.; Estrellés, E. (2002). Aproximación al estudio anatomo histológico de la micorriza de Ophioglossum lusitanicum L. Butlletí Societat Micològica Valenciana. (7):55-60. http://hdl.handle.net/10251/106303S5560

Effects of ozone on the foliar histology of the mastic plant (Pistacia lentiscus L.)

[EN] An open-top chamber study was conducted to investigate the tissue and cellular-level foliar effects of ozone (O-3) on a Mediterranean evergreen species, the mastic plant (Pistacia lentiscus L.). Plants were exposed at three different O-3 levels, and leaf samples were collected periodically from the beginning of the exposure. Although no visible foliar injury was evident, alterations of the plastids and vacuoles in the mesophyll were observed. Senescence processes were accelerated with an anomalous stacking of tannin vacuoles, and a reduction in the size and number of the chloroplasts. Overall, most of the modifications induced by O-3 were consistent with previously reported observations on deciduous broadleaf species, with the exception of alterations in the cells covering the secretory channels, reported here as a new finding. Comments on the feasibility of using microscopy to validate O-3 related field observations and subtle foliar injury are also given. (C) 2004 Elsevier Ltd. All rights reserved.Reig Armiñana, J.; Calatayud, V.; Cerveró, J.; García-Breijo, F.; Ibars, A.; Sanz, MJ. (2004). Effects of ozone on the foliar histology of the mastic plant (Pistacia lentiscus L.). Environmental Pollution. 132(2):321-331. doi:10.1016/j.envpol.2004.04.006S321331132

Characterization of the responses to saline stress in the symbiotic green microalga Trebouxia sp. TR9

Main conclusion: For the first time we provide a study on the physiological, ultrastructural and molecular effects of salt stress on a terrestrial symbiotic green microalga, Trebouxia sp. TR9. Although tolerance to saline conditions has been thoroughly studied in plants and, to an extent, free-living microalgae, scientific data regarding salt stress on symbiotic lichen microalgae is scarce to non-existent. Since lichen phycobionts are capable of enduring harsh, restrictive and rapidly changing environments, it is interesting to study the metabolic machinery operating under these extreme conditions. We aim to determine the effects of prolonged exposure to high salt concentrations on the symbiotic phycobiont Trebouxia sp. TR9, isolated from the lichen Ramalina farinacea. Our results suggest that, when this alga is confronted with extreme saline conditions, the cellular structures are affected to an extent, with limited chlorophyll content loss and photosynthetic activity remaining after 72 h of exposure to 5 M NaCl. Furthermore, this organism displays a rather different molecular response compared to land plants and free-living halophile microalgae, with no noticeable increase in ABA levels and ABA-related gene expression until the external NaCl concentration is raised to 3 M NaCl. Despite this, the ABA transduction pathway seems functional, since the ABA-related genes tested are responsive to exogenous ABA. These observations could suggest that this symbiotic green alga may have developed alternative molecular pathways to cope with highly saline environments.Fil: Hinojosa Vidal, Ernesto. Universidad de Valencia; EspañaFil: Marco, Francisco. Universidad de Valencia; EspañaFil: Martínez Alberola, Fernando. Universidad de Valencia; EspañaFil: Escaray, Francisco José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); ArgentinaFil: García Breijo, Francisco J.. Universidad Politécnica de Valencia; EspañaFil: Reig Armiñana, José. Universidad Politécnica de Valencia; EspañaFil: Carrasco, Pedro. Universidad de Valencia; EspañaFil: Barreno, Eva. Universidad de Valencia; Españ