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The accuracy of the description regarding tree architecture is crucial for data processing. LiDAR technology is an efficient solution for capturing the characteristics of individual trees. The aim of the present study was to analyze tree shape variability in a mixed oak forest consisting of four European white oak species: Quercus petraea, Q. frainetto, Q. pubescens, and Q. robur. Moreover, we tested for association between tree shape and individual heterozygosity and whether oak trees identified as pollen donors in a previous genetic study have a larger size in terms of crown and trunk characteristics than non-donors. The woody structure of a tree was defined by the quantitative structure model (QSM) providing information about topology (branching structure), geometry, and volume. For extracting the 3D point clouds a high-speed 3D scanner (FARO FocusS 70) was used. The crown variables were strongly correlated to each other, the branch volume being influenced by branch length, maximum branch order, and the number of branches but not influenced by diameter at breast height (DBH), trunk length, trunk volume, or tree height. There was no relationship between the individual heterozygosity based on nuclear microsatellite genetic markers and crown and trunk characteristics, respectively. Branch volume, total area, DBH, trunk volume, and the total volume of tree were significantly larger in pollen donors compared to non-donor Q. petraea trees. Thus, the mean branch volume was more than three times higher. Pollen donors had nearly two and half times larger total area in comparison to non-donor individuals. Our results suggest that a thorough characterization of tree phenotype using terrestrial laser scanning may contribute to a better understanding of mating system patterns in oak forests.

The aging of wines is a process used to preserve wine but also to enhance its properties. It is a process of great interest, mainly because of the additional properties it adds to wines and because of its economic implications. Historically, barrels have been employed for centuries for preserving and aging wine due to their resistance and relative impermeability. In general terms, the wine aging process can be divided into two phases: oxidative and reductive aging. Oxidative aging traditionally takes place in barrels while reductive phase occurs in the bottle. During both processes, oxygen plays a fundamental role as well as other factors, for instance: temperature, light, bottle position, microbial growth or storage time. Likewise, during the aging process, a series of chemical reactions take place influencing the composition and organoleptic profile of wine. At this point, oxidative aging in barrels is a fundamental step. Barrels are directly involved in the produced changes on wine’s composition due to the transference of oxygen and phenolic and aromatic compounds from wood to wine. This way, barrels act as an active vessel capable of releasing compounds that affect and improve wine’s characteristics. Regarding, the importance of barrels during aging process, some attention must be given to the species most used in cooperage. These species are conventionally oak species, either French or American. However, other non-conventional species are currently being studied as possible wood sources for the production of wines, such as chestnut robinia or other oak species. In the last decades, new approaches have been developed for barrel aging to find new alternatives more suitable, affordable and feasible to sanitize the process, such as other materials different from wood or the use of wood chips, which is regulated since 2006 by the EU. However, even though some of them have shown promising data, barrels are currently the most used technology for the oxidative stage of table wines aging. Proyecto IBERPHENOL | Ref. 0377-Iberphenol-6-E Proyecto NANOEATERS | Ref. 0181-NANOEATERS-01-E Programa Iberoamericano de Ciencia y Tecnología | Ref. CYTED — AQUA-CIBUS, P317RT0003

International audience; Many perennial plants display masting, that is, fruiting with strong interannual variations, irregular and synchronized between trees within the population. Here, we tested the hypothesis that the early flower phenology in temperate oak species promotes stochasticity into their fruiting dynamics, which could play a major role in tree reproductive success. From a large field monitoring network, we compared the pollen phenology between temperate and Mediterranean oak species. Then, focusing on temperate oak species, we explored the influence of the weather around the time of budburst and flowering on seed production, and simulated with a mechanistic model the consequences that an evolutionary shifting of flower phenology would have on fruiting dynamics. Temperate oak species release pollen earlier in the season than do Mediterranean oak species. Such early flowering in temperate oak species results in pollen often being released during unfavorable weather conditions and frequently results in reproductive failure. If pollen release were delayed as a result of natural selection, fruiting dynamics would exhibit much reduced stochastic variation. We propose that early flower phenology might be adaptive by making mast-seeding years rare and unpredictable, which would greatly help in controlling the dynamics of seed consumers.

There is a lack of knowledge about the possibility that plants facing abiotic stressors, such as drought, have an altered perception of a pulse of O3 and incur in alterations of their signalling network. This poses some concerns as to whether defensive strategy to cope episodic O3 peaks in healthy plants may fail under stress. In this study, a set of saplings of two Mediterranean deciduous species, Quercus cerris and Q. pubescens, was subjected to water withholding (20% of daily evapotranspiration for 15 days) while another set was kept well-watered. Saplings were then subjected to a pulse of O3 (200 nl l−1 for 5 h) or maintained in filtered air. Q. pubescens had a more severe decline of photosynthesis and leaf PDΨw (about −65% and 5-fold lower than in well-watered ones) and events of cell death were observed under drought when compared to Q. cerris, which is supportive for a higher sensitivity to drought exhibited by this species. When O3 was applied after drought, patterns of signalling compounds were altered in both species. Only in Q. pubescens, the typical O3-induced accumulation of apoplastic reactive oxygen species, which is the first necessary step for the activation of signalling cascade, was completely lost. In Q. cerris the most frequent changes encompassed the weakening of peaks of key signalling molecules (ethylene and salicylic acid), whereas in Q. pubescens both delayed (salicylic and jasmonic acid) or weakened (ethylene and salicylic acid) peaks were observed. This is translated to a higher ability of Q. cerris to maintain a prompt activation of defensive reaction to counteract oxidative damage due to the pollutant. Our results reveal the complexity of the signalling network in plants facing multiple stresses and highlight the need to further investigate possible alteration of defensive mechanism of tree species to predict their behavior.