Plants are known to respond to warming temperatures. Few studies, however, have included the temperature experienced by the parent plant in the experimental design, in spite of the importance of this ...factor for population dynamics.
We investigated the phenological and growth responses of seedlings of two key temperate tree species (Fagus sylvatica and Quercus robur) to spatiotemporal temperature variation during the reproductive period (parental generation) and experimental warming of the offspring. To this end, we sampled oak and beech seedlings of different ages (1–5 years) from isolated mother trees and planted the seedlings in a common garden.
Warming of the seedlings advanced bud burst in both species. In oak seedlings, higher temperatures experienced by mother trees during the reproductive period delayed bud burst in control conditions, but advanced bud burst in heated seedlings. In beech seedlings, bud burst timing advanced both with increasing temperatures during the reproductive period of the parents and with experimental warming of the seedlings. Relative diameter growth was enhanced in control oak seedlings but decreased with warming when the mother plant experienced higher temperatures during the reproductive period.
Overall, oak displayed more plastic responses to temperatures than beech. Our results emphasise that temperature during the reproductive period can be a potential determinant of tree responses to climate change.
English oak (Quercus robur) and European beech (Fagus sylvatica) are amongst the most common tree species growing in Europe, influencing the annual biogenic volatile organic compound (BVOC) budget in ...this region. Studies have shown great variability in the emissions from these tree species, originating from both genetic variability and differences in climatic conditions between study sites. In this study, we examine the emission patterns for English oak and European beech in genetically identical individuals and the potential variation within and between sites. Leaf scale BVOC emissions, net assimilation rates and stomatal conductance were measured at the International Phenological Garden sites of Ljubljana (Slovenia), Grafrath (Germany) and Taastrup (Denmark). Sampling was conducted during three campaigns between May and July 2014. Our results show that English oak mainly emitted isoprene whilst European beech released monoterpenes. The relative contribution of the most emitted compounds from the two species remained stable across latitudes. The contribution of isoprene for English oak from Grafrath and Taastrup ranged between 92 and 97 % of the total BVOC emissions, whilst sabinene and limonene for European beech ranged from 30.5 to 40.5 and 9 to 15 % respectively for all three sites. The relative contribution of isoprene for English oak at Ljubljana was lower (78 %) in comparison to the other sites, most likely caused by frost damage in early spring. The variability in total leaf-level emission rates from the same site was small, whereas there were greater differences between sites. These differences were probably caused by short-term weather events and plant stress. A difference in age did not seem to affect the emission patterns for the selected trees. This study highlights the significance of within-genotypic variation of BVOC emission capacities for English oak and European beech, the influence of climatic variables such as temperature and light on emission intensities and the potential stability in relative compound contribution across a latitudinal gradient.
Genomics of Fagaceae Kremer, Antoine; Abbott, Albert G; Carlson, John E ...
Tree genetics & genomes,
06/2012, Volume:
8, Issue:
3
Journal Article
Peer reviewed
Open access
An overview of recent achievements and development of genomic resources in the Fagaceae is provided, with major emphasis on the genera Castanea and Quercus. The Fagaceae is a large plant family ...comprising more than 900 species belonging to 8–10 genera. Using a wide range of molecular markers, population genetics and gene diversity surveys were the focus of many studies during the past 20 years. This work set the stage for investigations in genomics beginning in the early 1990s and facilitated the application of genetic and quantitative trait loci mapping approaches. Transferability of markers across species and comparative mapping have indicated tight macrosynteny between Quercus and Castanea. Omic technologies were more recently developed and the corresponding resources are accessible via electronic and physical repositories (expressed sequence tag sequences, single-nucleotide polymorphisms, candidate genes, cDNA clones, bacterial artificial chromosome (BAC) libraries) that have been installed in North America and Europe. BAC libraries and physical maps were also constructed in Castanea and Quercus and provide the necessary resources for full nuclear genome sequencing projects that are currently under way in Castanea mollissima (Chinese chestnut) and Quercus robur (pedunculate oak).
Chloroplast DNA variation was investigated in 42 populations of pedunculate oak,
Quercus robur
L., in the European part of Russia, Belarus, Poland, Ukraine, the Urals, and the Caucasus. Restriction ...analysis and sequencing, as well as chloroplast DNA microsatellite loci (cpSSR), were used as genetic markers. For successful amplification and sequencing, new oak-specific primers were designed. For the first time for
Q. robur
, nucleotide sequences of three fragments (
psa
A
-trn
S,
psb
C
-trn
D, and
trn
T
-trn
F) were obtained with the determination of phylogenetic relationships among 13 identified haplotypes. In the eastern part of the range, several divergent chloroplast DNA lineages were identified. The haplotype groups were characterized by a nonrandom geographic distribution, which probably reflected the history of oak colonization in these regions. Sharp population differentiation in terms of haplotype composition and the level of variation was revealed. Specifically, in the eastern part of the Russian Plain and in the Urals, two haplotypes are widespread, which are disappearing in the west (Northwestern Russia, Belarus, Poland, and Western Ukraine), where nine haplotypes are found that are absent in east. Geographic structure of chloroplast DNA variation in pedunculate oak from Eastern Europe is similar to that in small-leaved lime (Semerikova et al., 2020), another representative of European temperate forests, in which, like in oak in this part of the range, sharp differences between western and eastern populations were observed. It seems likely that this is the result of postglacial colonization by both species from different, long isolated refugia, some of which were located in the east of the studied areas. In the Urals, parallel differentiation of oak and lime between the southern part (Ural River and Belaya River basins) and more northern regions (Ufa River basin and Middle Urals) was revealed, which can be explained by different historical colonization patterns of these regions by broad-leaved vegetation.
Across Britain and continental Europe there are many ancient Castanea sativa trees of great significance for natural and cultural heritage, yet scant assessment has been made of them for ...dendrochronological information. This paper describes the dendrochronological analysis of 28 Castanea sativa trees (veteran historic trees, forest trees and coppice stems) sampled from 15 sites in southern Britain: 56 growth-ring sequences were collected for analysis, by boring living trees and by cutting transverse sections from dead fallen trees and previously cut stumps. Twenty-three single-tree sequences from 14 sites were cross-matched (t ≥3.5) and then cross-dated with 17 oak Quercus reference chronologies from England and northern France: a Castanea sativa master chronology spanning AD 1660–2014 has been created. The results demonstrate the viability of dendrochronological analysis of Castanea sativa wood; and confirm that Castanea sativa can be cross-dated with oak Quercus reference chronologies, inter-regionally and inter-nationally. The findings provide the potential means for dating Castanea sativa timbers sampled from palaeoenvironmental and historical contexts. The extraction of sawn sections from long-dead (up to 60 years in this study) trees and stumps is proven to be a reliable method for dating veteran trees in cultural landscapes and ancient woodlands; and for revealing the growth history of historic/iconic trees. The germination dates calculated for the Castanea sativa trees in this study span the period AD 1640–1943. The inaccuracy of estimating veteran Castanea sativa tree ages from girth measurements is highlighted.
Geographically isolated and small populations outside a species' central distribution range are likely to be of major importance to a species' ability to quickly adjust its distribution range to ...global change dynamics. Gene flow from the outside plays a pivotal role in the fate of these marginal populations. It has been proposed that spatial fragmentation and perceived geographic isolation do not necessarily reflect a loss of genetic connectivity in tree species. However, the spatial limits of long-distance gene flow, as well as its magnitude and impact, are still generally unknown. In the present study, we analyzed long-distance pollen-mediated gene flow into an isolated relict stand consisting of 7 individuals of Quercus robur L. based on a total sample of 177 trees and 9 microsatellite loci. We show that pollen-mediated gene flow across more than 80 km in this wind-pollinated tree species contributed at least 35% of all successful pollinations in the investigated isolated and small oak stand at the eastern limit of the species' distribution. The observed pollen immigration shaped the genetic diversity of acorn progenies in the stand and might explain the comparably high genetic diversity in the persisting adult population.
Rationale We investigated the applicability of tree-ring whole-wood material for delta super(18)O and delta super(13)C analysis in comparison with the more time- and resource-intensive use of ...cellulose, by considering possible variability between (i) five different tree species (Fagus sylvatica, Quercus robur, Picea abies, Abies alba, Pseudotsuga menziesii), (ii) two sites that differ in soil moisture, and (iii) climate conditions within a 10-year period. Methods Stem cores of 30 individual trees (n=3 trees per each species and site) were sampled from two sites in south Germany (Bavaria), and tree rings within sapwood of the years 2001-2010 were separated. The delta super(18)O and delta super(13)C values from homogenized tree-ring whole wood and from extracted cellulose were measured by mass spectrometry. Species-specific offsets in isotope values were analyzed and the responses in isotopic signature to climate variability including a single drought event were compared between whole-wood and cellulose. Results A constant offset in delta super(18)O values of ca 5 ppt between wood and cellulose was observed for most species independent of site conditions, with a significant difference between beech and Douglas-fir, while inter-annual variability was only observed in oak. The offset in delta super(13)C values ranged between 1.45 and 1.84 ppt across species, sites and years. Both materials generally showed similar strength in responses to temperature, precipitation and soil water availability, particularly for conifers. Resistance to severe drought stress - partly more strongly reflected in the delta super(13)C values of cellulose - was lower for conifers than for the deciduous species. Conclusions Wood material from the sapwood of the studied tree species is as useful as cellulose for studying environmental effects on tree-ring delta super(18)O and delta super(13)C values at a short-term scale as considered in most ecophysiological studies. The more variable response of oak may require further investigations.
Following disturbances, ecosystems are more susceptible to invasion by non-native species. Furthermore, it is important to determine the impact of alien tree species on soil regeneration processes ...during secondary succession. In this study, we analyzed the effect of native and late successional common oak (Quercus robur) and non-native red oak (Q. rubra) on soil physicochemical (pH, carbon, and nutrient content) and microbial properties (microbial biomass Cmic and respiration RESP) nearly 30 years after severe fire disturbance. Post-fire soils under Q. rubra had organic horizons with a greater mass, lower pH values, and depleted nutrient (N, Ca, K, Mg, and P) contents than soils under Q. robur. The impact of Q. robur as a late successional species on soil properties 30 years after a disturbance was similar to that of pioneer species (Scots pine, European larch, common birch, and black alder), as is indicated in previous studies. Most of the studied physicochemical (bulk density, soil organic carbon, N, Ca, K, and P content) and microbial (RESP and Cmic) soil parameters under Q. robur were within the ranges found for post-fire soils under pioneer tree species. Only the pH and Mg and Na contents in organic horizons were higher under Q. robur than under pioneer species. Our results indicate that Q. robur could be a valuable addition to reforestation sites after fire disturbance, especially in more fertile microhabitats. Due to the depletion of soil nutrients, care should be taken when introducing Q. rubra during the reforestation of post-fire sites, especially in larger groups.
We analysed two groups of Quercus robur trees, growing at nearby plots with different micro-location condition (W-wet and D-dry) in the floodplain Krakovo forest, Slovenia. In the study we compared ...the growth response of two different tree groups to environmental variables, the potential signal stored in earlywood (EW) structure and the potential difference of the information stored in carbon isotope discrimination of EW and latewood (LW). For that purpose EW and LW widths and carbon isotope discrimination for the period 1970-2008 AD were measured. EW and LW widths were measured on stained microscopic slides and chronologies were standardised using the ARSTAN program. α-cellulose was extracted from pooled EW and LW samples and homogenized samples were further analysed using an elemental analyser and IRMS. We discovered that W oaks grew significantly better over the whole analysed period. The difference between D and W oaks was significant in all analysed variables with the exception of stable carbon isotope discrimination in latewood. In W oaks, latewood widths correlated with summer (June to August) climatic variables, while carbon isotope discrimination was more connected to River Krka flow during the summer. EW discrimination correlated with summer and autumn River Krka flow of the previous year, while latewood discrimination correlated with flow during the current year. In the case of D oaks, the environmental signal appears to be vague, probably due to less favourable growth conditions resulting in markedly reduced increments. Our study revealed important differences in responses to environmental factors between the two oak groups of different physiological conditions that are preconditioned by environmental stress. Environmental information stored in tree-ring features may vary, even within the same forest stand, and largely depends on the micro-environment. Our analysis confirmed our assumptions that separate EW and LW analysis of widths and carbon isotope discrimination provides complementary information in Q. robur dendroecology.
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