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International audience; AbstractKey messageLarge genetic variation was found inPrunus aviumL. populations from the northern parts of the species distribution range. The ranking of genotypes in terms of growth was stable when tested at three trial sites within the northern parts of the species distribution range.ContextPeripheral populations especially those in the leading edge are isolated from rest of the areas in the species distribution range. This can make them less genetically diverse yet genetically distinct from the rest of the populations in the species distribution range. Evaluation of their genetic diversity is thus crucial in understanding the local adaptation potential of a species.AimsWe investigated the genetic diversity and genotype by environment interaction at the northern parts of the distribution range of P. avium.MethodsQuantitative genetic variation of growth, stem form, and spring phenology were assessed in progenies from 93 plus trees of P. avium selected from 43 locations at the north of the species distribution range in Sweden and tested at two Swedish sites and one Danish site.ResultsWe find large quantitative genetic variation in growth and phenology at the northern part of the distribution range of P. avium. Only a limited genotype by environment interaction was observed with no clear indication of local adaptation at the northern parts of the species distribution.ConclusionWe conclude that P. avium harbors a high level of genetic diversity at the north of its distribution range. Present patterns therefore reflect more likely the recent introduction of the species and dispersal dynamics rather than a long-term loss of diversity along South-North ecological clines during the Holocene. With no indications of genetic depletion in growth or phenology, the gene pool in the breeding program is considered suitable for the future propagation of the species in the tested area.

Terrestrial laser scanning (TLS) technology is a powerful tool for assessing tree growth based on time series analysis, as it allows a level of scrutiny not achievable using established destructive techniques.[br/] We applied TLS technology to 21 wild cherry trees grown in a research plot near Breisach (southern Germany) in order to build quantitative structure models (QSMs) for each tree. Scans were carried out over three subsequent years (2012-2014), so that three QSMs per each tree were constructed.[br/] Using the above approach, we were able to assess the annual growth of the individual wild cherry trees in terms of diameter and height, stem and branch volume, and the merchantable timber fraction. In addition, the growth of single branches of sample trees was detected and quantified. The availability of QSMs based on TLS-derived data allowed the accurate determination of crown length and width, as well as the volume reduction as the result of the tree pruning applied after the first scan (2012). The aboveground biomass (AGB) was assessed for each tree based on the QSM-derived volume and published wood density values for wild cherry, and then compared with AGB values estimated with standard allometric methods, obtaining a very high correlation (r(adj)(2) = 0.941).[br/] We concluded that the proposed approach is an effective non-destructive technique to accurately assess the increase of tree biomass, and discuss its future application in the forestry sector.

This contributed volume was produced with funding from EU Research Infrastructure Action "TREEBREEDEX". Contract Number 026076; Forest tree breeding has been ongoing for more than 70 years across Europe. It has successfully generated improved varieties for the major economical forest tree species. They are part of the present European forestry landscape and largely contribute to intensive wood production and other forest activities. In this book, we describe the state-of-art of breeding for the main forest tree species. We provide a comprehensive, unique and up-to-date overview of the major scientific results and breeding achievements gathered from the many programmes scattered across Europe. The book is divided into 10 chapters, each as a monograph corresponding to a species or group of species Abies spp., (Larix spp., Picea abies, Picea sitchensis, Pinus sylvestris, Pseudotsuga menziesii, and Mediterranean pines; Acer pseudoplatanus, Fraxinus excelsior, and Prunus avium). Each of them is written by a group of experts and focuses on the distribution and economical importance of the species; motivation for breeding and breeding objectives; intraspecific genetic variability, breeding populations and breeding strategy; forest reproductive material deployment including mass-propagation and, prospects and perspectives for joint research and breeding. The book is a unique and up-dated source of information for students, researchers and professionals interested in the genetics and domestication of forest tree species.

Wild cherry (Prunus avium L.) is native from central-eastern European temperate forests and it has only recently been introduced in intensive forest tree farming practices outside its natural range. Characterised by allogamy with pollination provided by honey bees, it is also able to spread by root stumps in juvenile phases of the ecosystem. Wild cherry cultivation for wood production has started in the early 1980s in Western Europe and then, more recently, in Eastern Europe. It is now an important commercial species in all the temperate areas of Europe – namely Spain, France, Italy, Germany, the Netherlands, Belgium and Great Britain – where most progress has been made in breeding and selection. Due to the higher aesthetic value of its wood, wild cherry is nowadays overcoming other valuable species such as walnut. Unfortunately, selection and breeding programmes have now effectively come to a reduction of funds for planting. This monograph presents the main biological features of the species relative to breeding and it describes the work carried out in breeding and propagation techniques across 14 European countries. Main results in terms of genetic parameters and trade of reproductive materials are then summarised. Numerous references are provided for the interested reader.

[EN] Cherry leaf spot (Blumeriella jaapii (Rehm) Arx.) is a very serious disease of wild cherry (Prunus avium L.), which produces premature leaf defoliation and vigor decrease. In two clonal seed orchards of P. avium naturally infected by B. jaapii, spatial heterogeneity and autocorrelation of neighbor damage caused by cherry leaf spot impeded proper analysis of the fungus incidence. The iterative spatial analysis (ISA), based on variography and kriging, was successfully used to eliminate the effect of this spatial heterogeneity in analysis of genetic variation in susceptibility to B. jaapii. Significant differences among P. avium clones were found, with moderate to high broad-sense heritability estimates. Genetic by environment interactions, although significant, were not quantitatively important. A strong relationship between leaf spot susceptibility and bud burst was found. However, other factors must be affecting the genetic variation in leaf spot susceptibility, as differences among clones remained highly significant when considering the bud burst as a covariate in the genetic model., [FR] Blumeriella jaapii (Rehm) Arx. est une des causes principales du dépérissement du merisier (Prunus avium L.) : il produit une défoliation prématurée et réduit la vigueur des arbres. Dans deux vergers à graines de clones de merisier naturellement infectés par B. jaapii, l’hétérogénité spatiale des dégâts et l’autocorrélation entre voisins empêchent une analyse correcte de l’incidence du champignon. Afin d’éliminer ces effets et d’étudier correctement la variabilité génétique de la susceptibilité au champignon, on a utilisé avec succès l’analyse itérative spatiale (ISA), basée sur la variographie et le krigeage. Des différences significatives entre clones existent pour la sensibilité au champignon. L’héritabilité clonale pour ce caractère est modérée à forte. Bien que l’interaction clone × site soit significative, elle n’est pas quantitativement importante. Par ailleurs, on a trouvé une relation étroite entre la susceptibilité au champignon et le débourrement végétatif. Néanmoins, d’autres facteurs doivent affecter la variabilité génétique à la susceptibilité, car les différences entre clones restent très significatives même quand on utilise le débourrement comme covariable dans le modèle statistique, RD and RZ were funded by an INIA-CCAA postdoctoral fellowship. The study was partially financed by the INIA project RTA05-57-C05-03.

International audience; Browsing by mammalian herbivores may help regulate the balance between woody and herbaceous vegetation where agricultural land has been abandoned. Until now, the potential of controlled grazing as a research tool has not yet been fully utilized. In this study, we used an enclosure-based experiment to assess the impact of browsing by red deer on the fate of seedlings on a woodland edge. Species, size, number of lateral shoots, and relative location of seedlings were recorded in 1 m2 plots (n = 57) distributed among four vegetation types. From autumn 2000 to winter 2002, after the stay of three tame hinds in the enclosure for 5-day periods in each season (a year-round deer density of 15 hinds/km2), we checked for loss or browsing damage of seedlings. From autumn 2000 to summer 2001, we additionally recorded the diurnal time spent feeding by the hinds during days 1, 3, and 5, and we simulated their food intake by hand during days 2 and 4. Mortality rates for willow Salix caprea and ash Fraxinus excelsior was higher than for silver fir Abies alba seedlings. Losses due to dehydration, which peaked under coniferous, were counterbalanced by growth of new seedlings. Loss due to browsing was uncommon. Deer impact on coniferous seedlings was insignificant all year long. More broad-leaved seedlings were browsed in spring and summer than in winter. Leader browsing increased with height, most of the taller seedlings occuring in herbaceous vegetation, especially wild cherry Prunus avium. Previously damaged seedlings suffered significantly higher leader browsing than previously undamaged ones. Behavioural observations showed that old pasture was selected by foraging deer all year-round. In autumn, spring and summer, due to quick depletion, the relative contribution of seedlings to the total food intake peaked during day 1, most (>75%) concerning wild cherry. Our results suggest that deer browsing on woody seedlings has more to do with species preference, height structure, growth, and seasonal phenology of seedlings than with induced mortality. Choice of previously damaged seedlings and non-random habitat use by deer can prove useful by minimizing natural regeneration of seedlings close to pastures. Further work is required on long term controlled browsing experiments to better understand natural regeneration of mixed woodland species.; L'abroutissement par les herbivores peut permettre le maintien de milieux ouverts après l'abandon de l'agriculture. Jusqu'à présent, cette possibilité d'utiliser un paturage contrôlé n'a pas été recherché complètement. Dans cette étude, nous avons réalisé une expérimentation dans un enclos pour mesurer l'impact de l'abroutissement du cerf sur une régénération forestière. La nature des essences, leur hauteur, le nombre de pousses et leur localisation ont été inventoriées sur des placettes d'1 m2 (n=57). Suite au passage de 4 biches imprégnées pendant 5 jours consécutifs à chaque saison (correspondant à une densité relative à l'année de 15 biches/km2)entre l'automne 2000 et l'hiver 2002, les inventaires ont permis de suivre la mortalité des semis et la pression d'abroutissement. Entre l'automne 2000 et l'été 2001, le temps passé à se nourrir dans la journée par les biches a été évalué (pour les jours 1,3 et 5) de même que la quantité ingérée a été estimée les jours 2 et 4. La mortalité des semis est plus importante pour le saule Salix caprea et le frêne Fraxinus excelsior que pour le sapin pectiné Abies alba. Les pertes dues à la sécheresse importante des semis sous les résineux étaient compensées par le développement de nouveaux semis. Les pertes dues à l'abroutissement sont négligeables. L'impact du cerf sur la régénération des résineux est négligeable tout au long de l'année. Les semis d'essences feuillues sont consommées essentiellement au printemps et en été. L'abroutissement de la pousse terminale des feuillus est corrélée à leur hauteur notamment pour les semis de merisier. les semis auparavant consommés sont plus sujets à être abroutis que ceux qui ne l'ont jamais été. Les observations directes ont montré que la partie de l'enclos correspondant à une ancienne pâture était plus utilisée par les biches tout au long de l'année. A l'automne, au printemps et en été la contribution relative des semis d'essences forestières à la quantité de nourriture ingérée passait par un pic (>75%)puis diminuait fortement après la première journée passée dans l'enclos en raison d'une forte diminution du stock disponible notamment de semis de merisiers. Nos résultats suggèrent que les effets de l'abroutissement du cerf sur l'acquisition de la régénération sont peu importants et que le problème principal est lié à la nature des essences et à leur relative attractivité, leur hauteur, la saison. Pour limiter l'impact du cerf en raison de l'utilisation de son habitat, il peut s'avérer utile de ne pas mettre en régénération des zones limitrophes de patures. Des travaux complémentaires au travers d'expérimentations de ce type sur le long terme pourront permettre de mieux comprendre les interactions entre le cerf et l'acquisition des régénérations forestières.

Growth results of field trials on three stands aged 8, 10 and 12 years respectively of wild cherry planted on former agricultural lands in combination with alder are presented. Four options are compared in each trial : A; wild cherry alone at 6 m by 7 m spacing (A) ; wild cherry at the same spacing but mixed with alder at low (B), medium (C) and high density (D). In two of the three trials, wild cherry is largely dominated by alder. Alder produces between 4.8 and 7.9 tons DM.ha-1.year-1 after 6 to 8 years. This biomass can be harvested by thinning. Alder improves wild cherry growth, total height, diameter and length of bole. Nevertheless, alder competes actively with wild cherry, thus raising the H/D ratio of wild cherry and may as such weaken the latter. Planting in combination with alder is an efficient way of successfully establishing wild cherry plantations on arable lands as long as the competition between these two species is properly managed subsequently., Les premiers résultats de croissance de trois plantations sur terres agricoles de Merisier avec accompagnement d'Aulne, âgées respectivement de 8, 10 et 12 ans, sont présentés. Sur chaque essai, quatre modalités sont comparées : A- Merisier seul à 6 m x 7 m ; B, C et D; Merisier à la même densité mélangé avec de l'aulne à densité faible (B), intermédiaire (C) et forte (D). Dans deux des trois essais, l'Aulne domine largement le Merisier et produit en 6 à 8 ans de 4,8 à 7,9 tonnes de matière sèche par hectare et par an de biomasse ligneuse exploitable par éclaircies. L'accompagnement d'aulne améliore la croissance en hauteur et diamètre du merisier et facilite la formation de sa bille de pied. Il concurrence cependant le Merisier, d'autant plus qu'il le domine, et aurait tendance à le déstabiliser en augmentant son facteur d'élancement. La plantation d'un accompagnement constitue une solution efficace pour réussir l'installation du merisier sur terre agricole à condition de bien maîtriser ensuite la compétition entre ces deux espèces.

Shoot cultures of chestnut, oak and wild cherry have been stored at low temperature (2°C) for 3, 6, 9 and 12 months. Cultures were stored immediately after the last subculture or 10 d later. Survival and morphogenetic parameters have been recorded at the end of each period of storage. Both survival and proliferation capacity of the explants were influenced by the timing of the transfer. When the explants were stored 10 d after the subculture, higher percentages of survival and multiplication rates were obtained. The 4 species studied may be maintained at 2°C for up to 1 year without subculturing., The work was partially supported by the EEC (ECLAIR, AGRE-0067).