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1.
Quercus robur (L.) and Q. petraea (Matt.) Liebl. are European oak species that often grow in forest soils with high soluble manganese (Mn2+) concentrations. We tested the effects of Mn2+ at concentrations of 0.0024 mM (control), 0.24 mM (typical of acidic forest soils) and 1.2 mM (typical of forest soils under strongly reducing conditions) on the growth, tissue anatomy, foliar element concentrations, subcellular element distribution and gas exchange of solution-cultured seedlings. At the highest Mn2+ concentration, seedlings were grown with and without an elevated concentration (1.2 mM) of magnesium (Mg2+). At 0.24 mM Mn2+, foliar Mn concentrations were higher than observed in the field. Vacuoles of the leaf epidermis and mesophyll were the main sites of manganese accumulation. High nutrient solution Mn2+ concentration significantly lowered foliar iron (Fe) and Mg concentrations. Elevated Mg2+ concentration raised the foliar Mg concentrations to control values, but Fe concentrations and gas exchange remained depressed. In seedlings grown in the 1.2 mM Mn2+ treatment without elevated Mg2+ damage to the phloem of the petioles and a reduction in root mass were observed in both species. The effects on shoot and root growth were greatest in Q. petraea. Alleviation of manganese toxicity symptoms by Mg2+ in Q. petraea was less effective than in Q. robur. Our results suggest that the soil solution Mn2+ concentrations that occur in European oak forests are unlikely to affect the distribution and performance of Q. robur and Q. petraea in the field. 相似文献
2.
《Scandinavian Journal of Forest Research》2012,27(3):297-308
A study of 33 provenances in Danish field trials with Quercus robur and Q. petraea was made between 1993 and 1998. The trials include Danish, Dutch, German, Norwegian and Swedish provenances, and were established between 1900 and 1988. Growth, flushing, stem form and epicormic shoot formation were studied. There were strong geographical clines for growth; however, the variation within regions was considerable. Time of flushing followed a more complex clinal pattern and was related to both latitude and distance from the ocean. Stem form was highly variable within different geographical regions and it is suggested that this could be caused by different management regimes in the past. Oaks from some locations in Sweden and Norway seemed especially straight. Stem form is one of the most important parameters for commercial oak management and could be seriously improved through breeding, as it was under considerable genetic control. Epicormic shoot production was in part under genetic control, but no geographical patterns were found. Danish provenances of Q. petraea were growing more rapidly than similar Q. robur on sandy locations. Quercus petraea produced fewer epicormic branches and stem form was equal to or better than Q. robur. Quercus petraea should be recommended for landscape use on windy locations in Denmark. 相似文献
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Quercus robur L. and Quercus petraea (Matt.) Liebl. are sympatric oak species with different ecological requirements. Quercus robur is more tolerant to waterlogging than Q. petraea. This ecological divergence may play a role in the maintenance of the two species despite the absence of an insurmountable reproductive barrier between them. We predicted that the genetic architecture of traits related to waterlogging tolerance differs between the species. To gain insight into this architecture in the absence of genetic markers for waterlogging tolerance, we compared populations of seedlings of each species for diversity in the expression of quantitative phenotypic traits induced by severe hypoxia. To determine the capacity for hypertrophied lenticel formation, we applied gas-impermeable mastic to stems of seedlings. Two months after application, the mastic treatment had induced the formation of 3 (+/- 2) cm(-2) hypertrophied lenticels in the absence of root hypoxia. Leaf epinasty during root hypoxia was an early predictor of seedling mortality. Four weeks of waterlogging resulted in greater epinasty in Q. petraea than in Q. robur, but fewer hypertrophied lenticels (16 +/- 6 versus 21 +/- 9 cm(-2)) and adventitious roots (2.7 +/- 4.7 versus 5.2 +/- 5.9). Differences between species in these traits were associated with differences in the frequencies of extreme phenotypes rather than with a generally higher tolerance to waterlogging in Q. robur seedlings. 相似文献
5.
Barigah TS Ibrahim T Bogard A Faivre-Vuillin B Lagneau LA Montpied P Dreyer E 《Tree physiology》2006,26(12):1505-1516
We assessed the irradiance-related plasticity of hydraulic architecture in saplings of Betula pendula Roth., a pioneer species; Acer pseudoplatanus L., Fraxinus excelsior L. and Quercus robur L., which are post-pioneer light-requiring species; and Quercus petraea Matt. Liebl. and Fagus sylvatica L. Plants were grown in pots in 36%, 16% and 4% of full sunlight. Hydraulic conductance was measured with a high-pressure flow-meter in entire, in situ root systems and in excised shoots. Leaf-specific whole-plant conductance (LSC) increased with irradiance, due, in part, to an effect of irradiance on plant size. In addition, there was a size-independent effect of irradiance on LSC due, in part, to an increase in root hydraulic conductance paralleled by an increase in root biomass scaled to leaf area. Changes in shoot conductivity also contributed to the size-independent plasticity of LSC. Vulnerability to cavitation measured in current-year twigs was much larger in shade-grown plants. Betula pendula had the highest whole-plant, root and shoot conductances and also the greatest vulnerability to cavitation. The other species were similar in LSC, but showed some variation in root conductance scaled to biomass, with Q. robur, Q. petraea and F. sylvatica having the lowest root conductance and susceptibility to cavitation. All species showed a similar irradiance-related plasticity in LSC. 相似文献
6.
Seedlings of two sympatric oak species, Quercus robur L. and Quercus petraea (Matt.) Liebl., were grown in common garden conditions to test for potential interspecific differences in intrinsic water-use efficiency (WUE). Intrinsic water-use efficiency was estimated based on carbon isotope composition of shoots (delta13C) and on gas exchange measurements (ratio of net CO2 assimilation rate to stomatal conductance (A/g(sw))). In addition, genotype x environment interactions were tested by subjecting the seedlings to four irradiance treatments (8, 18, 48 and 100% of incident solar irradiance) imposed by neutral shading nets, and, in the 100% irradiance treatment, two watering regimes. In all treatments, initial growth of Q. robur was faster than that of Q. petraea. In both species, there was a tight correlation between delta13C and A/g(sw). Intrinsic water-use efficiency increased with increasing irradiance (almost doubling from 8 to 100% irradiance), and this effect paralleled the increase in A with increasing irradiance. In full sun, WUE of Q. petraea seedlings was 10-15% higher than in Q. robur seedlings, with the difference attributable to a difference between the species in g(sw). The interspecific difference in WUE was maintained during drought, despite the appreciable increase in WUE and decrease in growth imposed by drought. No interspecific differences in WUE were observed at low irradiances, suggesting a strong genotype x environment interaction for WUE. These findings confirm the existence of interspecific genetic differences in WUE, but also show that there is large intraspecific variability and plasticity in WUE. The initially greater height and biomass increments in Q. robur seedlings illustrate the ability of this species to out-compete Q. petraea in the early stages of forest regeneration. For adult trees growing in closed canopies, the high WUE of Q. petraea may contribute significantly to its survival during dry years, whereas the low WUE of Q. robur may account for the frequently observed declines in adult trees of this species following drought. 相似文献
7.
The phenolic contents of eight in-vitro-cultivated chestnut clones (Castanea sativa Mill. and C. sativa x C. crenata Siebold & Zucc. hybrids) were analyzed both qualitatively and quantitatively. The aim of the work was to identify potential phenolic markers of: (i) juvenile or mature state; (ii) topophysical origin; and (iii) rooting capacity. A condensed tannin was detected in mature material but not in juvenile material, indicating that it could be used as a qualitative marker. Other qualitative phenolic differences were found between basal shoots and crown shoots of some clones, but it was not possible to discriminate among these materials in a general way. Canonical discriminant analysis was used for the study of quantitative markers. Differentiation between mature and juvenile material, and between materials differing in in vitro rooting capacity was possible according to the results of the analysis. Nevertheless, no significant quantitative differences were found between the phenolic content of material of basal shoot origin and that of crown shoot origin, indicating that the greater juvenility of material of basal origin compared with that of crown origin was not reflected in differences in phenolic content. 相似文献
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Provenance-specific growth responses to experimentally applied drought and air warming were studied in saplings of three European oak species: Quercus robur, Quercus petraea and Quercus pubescens. Four provenances of each species were grown in large open-top chambers and subjected to four climates: control, periodic drought, air warming or their combination in 3 subsequent years. Overall growth responses were found among species and provenances, with drought reducing shoot height growth and stem diameter growth and air warming stimulating shoot height growth but reducing stem diameter growth and root length growth. Differential growth responses in shoots, stems and roots resulted in altered allometric growth relations. Root length growth to shoot height growth increased in response to drought but decreased in response to air warming. Stem diameter growth to shoot height growth decreased in response to air warming. The growth responses in shoots and stems were highly variable among provenances indicating provenance-specific sensitivity to drought and air warming, but this response variability did not reflect local adaptation to climate conditions of provenance origin. Shoot height growth was found to be more sensitive to drought in provenances from northern latitudes than in provenances from southern latitudes, suggesting that genetic factors related to the postglacial immigration history of European oaks might have interfered with selective pressure at provenance origins. 相似文献
10.
The Wessex Silvicultural Group spent three years studying themanagement and silviculture of the oaks (Quercus robur L andQ petraea (Matt) Leibl) in the Wessex area. Low input methodsof establishment including the use of tree shelters and thetending and thinning of younger oak stands together with controlof timber quality were examined in twenty-one forests and estates.Environmental values were acknowledged. While Q robur has previouslypredominated, Q petraea is now generally preferred. 相似文献
11.
Explants from five clones of Quercus robur (three of juvenile origin and two from adult trees) were cultured on Gresshoff and Doy medium supplemented with 0.2 mg l(-1) 6-benzylaminopurine. Shoot proliferation from apical and nodal segments was influenced by both clone and type of explant. To increase the efficiency of the propagation procedure, donor shoots (20-25 mm in length and with 2 mm removed from the tip) were recultured at 4-week intervals, and the newly formed shoots harvested before each transfer. Under this regime, the multiplication coefficient (proportion of explants forming axillary shoots multiplied by the mean number of new 8-mm stem segments per explant) was greatest for the second crop and declined sharply by the fourth or fifth crop, in three of the four clones tested. Successive additions of fresh liquid medium to old cultures was much less effective than transfer to fresh medium in promoting axillary shoot production. Elongation of shoots before rooting was increased significantly (P < 0.05) in one of two clones tested by transfer to a medium containing either 0.1 or 1.0 mg l(-1) of zeatin. Addition of fresh liquid medium containing zeatin to old cultures failed to improve shoot elongation or axillary shoot production. However, treatment for 15 days with liquid medium containing 0.1 or 1.0 mg l(-1) indol-3-yl-acetic acid increased subsequent rooting. 相似文献
12.
Axial and radial water flow in the trunks of oak trees: a quantitative and qualitative analysis 总被引：1，自引：0，他引：1
Granier A Anfodillo T Sabatti M Cochard H Dreyer E Tomasi M Valentini R Bréda N 《Tree physiology》1994,14(12):1383-1396
Axial water flow in the trunks of mature oak trees (Quercus petraea (Matt.) Liebl. and Q. robur L.) was studied by four independent techniques: water absorption from a cut trunk, sap flowmeters, heat pulse velocity (HPV) and thermoimaging. Estimation of the total water flow with sap flowmeters, HPV and water absorption yielded comparable results. We concluded from dye colorations, thermograms and axial profiles of sap flow and heat pulse velocity that, in intact trunks, most of the flow occurred in the current-year ring, where early-wood vessels in the outermost ring were still functional. Nevertheless, there was significant flow in the older rings of the xylem. Total water flow through the trunk was only slightly reduced when air embolisms were artificially induced in early-wood vessels, probably because there was little change in hydraulic conductance in the root-leaf sap pathway. Embolization of the current-year vessels reactivated transport in the older rings. 相似文献
13.
We tested the hypothesis that changes in crown architecture of old pedunculate oak trees (Quercus robur L. ssp. robur Kl. et Kr. et Rol.) reduce leaf specific hydraulic conductance of shoots, thereby limiting stomatal conductance and assimilation of affected shoots. At the end of summer 1999, hydraulic conductance and leaf specific hydraulic conductance, measured with a high-pressure flow meter in 0.5- to 1.5-m long shoots, were 27 and 39% lower, respectively, in shoots of low vigor compared with vigorously growing shoots in a 165-year- old stand in southeastern Germany. Two types of bottlenecks to water transport can be identified in shoots of old oak trees, namely nodes and abscission zones. The reduction in hydraulic conductance was especially severe in shoots with diameters of less than 2 mm. Maximum stomatal conductance and maximum net assimilation rate increased significantly with hydraulic conductance and leaf specific hydraulic conductance. Our data support the hypothesis that changes in shoot and consequently crown architecture observed in aging trees can limit photosynthesis by reducing shoot hydraulic conductance. Thus, in addition to increasing pathway length and lower conductivity of xylem in old trees, structural changes in shoot and crown architecture need to be considered when analyzing water relations and photosynthesis in mature and declining trees. 相似文献
14.
Stabilized shoot cultures initiated from crown material of six adult Quercus robur L. trees and from basal epicormic shoots of a Quercus rubra L. tree showed good in vitro rooting capacity. An initial five-day dark period generally improved the rooting response but was detrimental to plantlet quality. There were clonal differences in rooting capacity. The concentration and exposure time of the indolebutyric acid (IBA) treatment were critical for root induction. In both species, best rooting efficiency was achieved by culture in medium containing 25 mg l(-1) IBA for 24 h and subsequent transfer to an auxin-free medium containing 1% activated charcoal. For all clones tested, the charcoal benefited both shoot quality and root system development, the latter being enhanced by the formation of many lateral roots. Total root system area and length, measured with a digital image analyzer, were significantly greater in medium containing charcoal than in medium lacking charcoal. Because darkening the basal part of the shoots with aluminum foil during the rooting phase only caused a small increase in rooting, we conclude that the large effect of charcoal on rooting was the result of adsorption of inhibitory compounds from the medium or the explant or both, rather than of basal darkening. Other factors affecting the rooting response of Q. robur were: (a) the position on the tree of the material from which cultures were initiated (the topophysical effect); and (b) shoot quality. Recycling the same horizontally placed explant on multiplication medium allowed three successive crops of shoots to be obtained, and rootability was typically maintained from crop to crop. 相似文献
15.
Seedlings of seven temperate tree species (Acer pseudoplatanus L., Betula pendula Roth, Fagus sylvatica L., Fraxinus excelsior L., Juglans regia L., Quercus petraea Matt. Liebl. and Quercus robur L.) were grown in a nursery under neutral filters transmitting 45% of incident global irradiance. During the second or third year of growth, leaf photosynthetic capacity (i.e., maximal carboxylation rate, Vcmax, maximal photosynthetic electron transport rate, Jmax, and dark respiration, Rd) was estimated for five leaves from each species at five or six leaf temperatures (10, 18, 25, 32, 36 and 40 degrees C). Values of Vcmax and Jmax were obtained by fitting the equations of the Farquhar model on response curves of net CO2 assimilation (A) to sub-stomatal CO2 mole fraction (ci), at high irradiance. Primary parameters describing the kinetic properties of Rubisco (specificity factor, affinity for CO2 and for O2, and their temperature responses) were taken from published data obtained with spinach and tobacco, and were used for all species. The temperature responses of Vcmax and Jmax, which were fitted to a thermodynamic model, differed. Mean values of Vcmax and Jmax at a reference temperature of 25 degrees C were 77.3 and 139 micromol m(-2) s(-1), respectively. The activation energy was higher for Vcmax than for Jmax (mean values of 73.1 versus 57.9 kJ mol(-1)) resulting in a decrease in Jmax/Vcmax ratio with increasing temperature. The mean optimal temperature was higher for Vcmax than for Jmax (38.9 versus 35.9 degrees C). In addition, differences in these temperature responses were observed among species. Temperature optima ranged between 35.9 and above 45 degrees C for Vcmax and between 31.7 and 43.3 degrees C for Jmax, but because of data scatter and the limited range of temperatures tested (10 to 40 degrees C), there were few statistically significant differences among species. The optimal temperature for Jmax was highest in Q. robur, Q. petraea and J. regia, and lowest in A. pseudoplatanus and F. excelsior. Measurements of chlorophyll a fluorescence revealed that the critical temperature at which basal fluorescence begins to increase was close to 47 degrees C, with no difference among species. These results should improve the parameterization of photosynthesis models, and be of particular interest when adapted to heterogeneous forests comprising mixtures of species with diverse ecological requirements. 相似文献
16.
Influence of gaseous pollutants on the epicuticular wax of Quercus robur . The effects of SO2, NO, and ozone on the epicuticular wax of Q. robur were studied by scanning electron microscopy and by measuring the contact angle of water droplets on the leaf surfaces. The treatments did not induce any significant differences in the wax micromorphology. 相似文献
17.
The susceptibility of oak seedlings (Quercus palustris, Quercus robur, Quercus rubra) and chestnut seedlings (Castanea sativa) to Phytophthora cinnamomi was tested. The dynamics of infection was examined in plant material raised in a rhizotron. In the oak species, primary root tissues were susceptible whereas secondary cortical tissues showed some resistance to P. cinnamomi. Secondary cortical tissues of the tap root in C. sativa were susceptible. Inoculations with P. cinnamomi were performed both in situ and on excised roots of mature Q. rubra. In both cases, the resistance of Q. rubra roots and shoots was negatively correlated with diameter at the inoculation point. Small roots (l–5-cm diameter) were resistant, whereas collar and trunk were susceptible. In contrast to oak, small excised roots of mature C. sativa (0.7–2-cm diameter) were susceptible to P. cinnamomi. This may explain why P. cinnamomi does not induce a decline of the attacked oaks, but rather a trunk canker. 相似文献
18.
Leaf disks of oak (Quercus petraea (Matt.) Liebl.) trees were subjected to rapid dehydration in air in the dark. Optimal photochemical efficiency of PS II (F(v)/F(M)), photochemical (q(P)) and nonphotochemical (q(NP)) quenchings of chlorophyll a fluorescence, and relative conductivity (C(r)) of leaf disk diffusate were measured in leaf disks with different water deficits (D). No effect of dehydration was detected before D reached values above 0.30. When D increased from 0.30 to 0.50, q(NP) increased without any change in q(P), which may indicate that thermal deexcitation of PS II increased, allowing reduced photochemical activity and maintenance of a large pool of oxidized primary acceptors (QA), although carbon reduction was impaired. Large changes in electron transport chain activity, leading to decreases in both q(P) and q(NP), appeared only in leaf disks subjected to severe water deficits (D > 0.60) and were correlated with a modification of membrane structure. However, stability of F(v)/F(M) indicated that the functional integrity of PS II was not altered until D reached values above 0.75. We conclude that the photosynthetic apparatus of Q. petraea is rather insensitive to leaf dehydration per se during drought under natural conditions. 相似文献
19.
Oaks emit large amounts of isoprene, a compound that plays an important role in tropospheric chemistry. Isopentenyl diphosphate isomerase (IDI, E.C. 5.3.3.2) catalyzes the isomerization of isopentenyl diphosphate (IDP) to dimethylallyl diphosphate (DMADP), and in isoprene-emitting plants, isoprene synthase (IS) converts the DMADP to isoprene. To study the role of IDI in isoprene biosynthesis of oak leaves, we compared IDI and IS activities in pedunculate oak (Quercus robur L.) and pubescent oak (Quercus pubescens Willd.) with the isoprene emission rates of these species. We developed a non-radioactive enzyme assay to detect IDI activity in crude leaf extracts of Q. robur. The substrate dependency of IDI activity showed biphasic kinetics with Michaelis constants (K(m)(IDP)) of 0.7 +/- 0.2 micro M for a high-affinity phase and 39.5 +/- 6.9 micro M for a low-affinity phase, potentially attributable to different IDI isoforms. Under standard assay conditions, the temperature optimum for IDI activity was about 42 degrees C, but IDI activity was detectable up to 60 degrees C. A sharp pH optimum appeared around pH 7, with 20 mM Mg(2+) also required for IDI activity. Neither IDI activity nor IS activity showed diurnal variation in Q. robur leaves. The sum of IDI activities showed a significant linear correlation with IS activity in both Q. robur and Q. pubescens leaves, and both enzyme activities showed a linear relationship to isoprene emission factors in leaves of these oak species, indicating the possible involvement of IDI in isoprene biosynthesis by oak leaves. 相似文献
20.
Functional traits and plasticity in response to light in seedlings of four Iberian forest tree species 总被引：1，自引：0，他引：1
We investigated the differential roles of physiological and morphological features on seedling survivorship along an experimental irradiance gradient in four dominant species of cool temperate-Mediterranean forests (Quercus robur L., Quercus pyrenaica Willd., Pinus sylvestris L. and Pinus pinaster Ait.). The lowest photochemical efficiency (F(v)/F(m) in dark-adapted leaves) was reached in deep shade (1% of full sunlight) in all species except Q. robur, which had the lowest photochemical efficiency in both deep shade and 100% of full sunlight. Species differed significantly in their survival in 1% of full sunlight but exhibited similar survivorship in 6, 20 and 100% of full sunlight. Shade-tolerant oaks had lower leaf area ratios, shoot to root ratios, foliage allocation ratios and higher rates of allocation to structural biomass (stem plus thick roots) than shade-intolerant pines. Overall phenotypic plasticity for each species, estimated as the difference between the minimum and the maximum mean values of the ecophysiological variables studied at the various irradiances divided by the maximum mean value of those variables, was inversely correlated with shade tolerance. Observed morphology, allocation and plasticity conformed to a conservative resource-use strategy, although observed differences in specific leaf area, which was higher in shade-tolerant species, supported a carbon gain maximization strategy. Lack of a congruent suite of traits underlying shade tolerance in the studied species provides evidence of adaptation to multiple selective forces. Although the study was based on only four species, the importance of ecophysiological variables as determinants of interspecific differences in survival in limiting light was demonstrated. 相似文献