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The aim of the present work was to evaluate and analyze the growth and mineral nutrition response of stone pine (Pinus pinea L.) seedlings, an economically important forest species. We analyzed the salinity effects on the kinetics of growth, development, and absorption of nutrients of plants cultivated under controlled conditions on a solid organic substrate. Pinus pinea plants were able to tolerate 25 mM NaCl concentration without reduced growth compared to the non-saline control. However, the salt concentration of 50 mM significantly affected the seedling growth after two weeks of treatment. Root growth activity was decreased more than the aerial parts at applied NaCl concentrations. On the other hand, seedlings restricted the transport of Na+ ions to the aerial parts and were strongly selective in favour of K+ ions. The presence of NaCl in the culture medium decreased the absorption rate and the export of K+ and Na+ ions to the aerial parts. This was reflected in the accumulation way of these two ions in the whole plant. Resumo O objetivo do presente trabalho foi avaliar e analisar a resposta de crescimento e nutrição mineral de mudas de pinheiro-manso (Pinus pinea L.), uma espécie florestal economicamente importante. Analisamos os efeitos da salinidade na cinética de crescimento, desenvolvimento e absorção de nutrientes de plantas cultivadas sob condições controladas em substrato orgânico sólido. As plantas de P. pinea foram capazes de tolerar a concentração de 25 mM de NaCl sem redução do crescimento em comparação com o controle não salino. No entanto, a concentração de sal de 50 mM afetou significativamente o crescimento das plântulas após duas semanas de tratamento. A atividade de crescimento das raízes foi mais reduzida do que as partes aéreas nas concentrações de NaCl aplicadas. Por outro lado, as plântulas restringiram o transporte de íons Na+ para a parte aérea e foram fortemente seletivas em favor dos íons K+. A presença de NaCl no meio de cultura diminuiu a taxa de absorção e a exportação de íons K+ e Na+ para as partes aéreas. Isso se refletiu na forma de acúmulo desses dois íons em toda a planta.

The knowledge of the effects of fire on soil properties is of particular concern in Mediterranean areas, where the effects of vegetation type are still scarce also. This research aimed: to assess the properties of burnt soils under different vegetation types; to highlight the soil abiotic properties driving the soil microbial biomass and activity under each vegetation type; to compare the biological response in unburnt and burnt soils under the same vegetation type, and between unburnt and burnt soils under different vegetation types. The soils were collected at a Mediterranean area where a large wildfire caused a 50% loss of the previous vegetation types (holm oak: HO, pine: P, black locust: BL, and herbs: H), and were characterized by abiotic (pH, water, and organic matter contents; N concentrations; and C/N ratios) and biotic (microbial and fungal biomasses, microbial respiration, soil metabolic quotient, and hydrolase and dehydrogenase activities) properties. The biological response was evaluated by the Integrative Biological Responses (IBR) index. Before the fire, organic matter and N contents were significantly higher in P than H soils. After the fire, significant increases of pH, organic matter, C/N ratio, microbial biomass and respiration, and hydrolase and dehydrogenase activities were observed in all the soils, especially under HO. In conclusion, the post-fire soil conditions were less favorable for microorganisms, as the IBR index decreased when compared to the pre-fire conditions.

5 Pág. Departamento de Tecnología de Alimentos​​, The epitopes of the major allergen of pine nut, Pin p 1, were analyzed using a peptide library and sera from patients with clinical allergy to pine nut in order to deepen into the allergenic characteristics of Pin p 1. Analyses of epitope similarities and epitopes location in a 3D-model were also performed. Results showed that three main regions of Pin p 1 containing 5 epitopes were recognized by patient sera IgE. The epitopes of Pin p 1 had important similarities with epitopes of allergenic 2S albumins from peanut (Ara h 2 and 6) and Brazil nut (Ber e 1). The epitopes of Pin p 1 were found in α-helices and coils in the 3D protein structure. Interestingly, all epitopes were found to be well-exposed in the protein surface, which suggests facile access for IgE-binding to the structure of Pin p 1 which is known to be highly resistant., This work was supported by a grant from the research program Talento Investigador of the Community of Madrid (Regional Ministry of Science, Universities, and Innovation, Madrid, Spain), and a grant from Strategic Health Action (AES 2020), Carlos III Health Institute, Spanish Ministry of Science and Innovation (to B.C) (Grant number: PI20/00351). B.C. is senior researcher in the research program Talento Investigador of the Community of Madrid (number: 2019-T1/BIO-12690). The funding sources had no role in the study design; in the collection, analysis and interpretation of data; in the writing of the manuscript; and in the decision to submit the article for publication.

BACKGROUND AND AIMS: Mediterranean trees have patterns of cambial activity with one or more pauses per year, leading to intra-annual density fluctuations (IADFs) in tree rings. We analysed xylogenesis (January 2015–January 2016) in Pinus pinea L. and Arbutus unedo L., co-occurring at a site on Mt. Vesuvius (southern Italy), to identify the cambial productivity and timing of IADF formation. METHODS: Dendrochronological methods and quantitative wood anatomy were applied and enabled IADF identification and classification. KEY RESULTS: We showed that cambium in P. pinea was productive throughout the calendar year. From January to March 2015, post-cambial (enlarging) earlywood-like tracheids were observed, which were similar to transition tracheids. The beginning of the tree ring was therefore not marked by a sharp boundary between latewood of the previous year and the new xylem produced. True earlywood tracheids were formed in April. L-IADFs were formed in autumn, with earlywood-like cells in latewood. In A. unedo, a double pause in cell production was observed, in summer and winter, leading to L-IADFs in autumn as well. Moreover, the formation of more than one IADF was observed in A. unedo. CONCLUSIONS: Despite having completely different wood formation models and different life strategies, the production of earlywood, latewood and IADF cells was strongly controlled by climatic factors in the two species. Such cambial production patterns need to be taken into account in dendroecological studies to interpret climatic signals in wood from Mediterranean trees.