-
Tree Physiology Feb 2001Pedunculate oak (Quercus robur L.) seedlings were grown for 3 or 4 months (second- and third-flush stages) in greenhouses at two atmospheric CO2 concentrations ([CO2])...
Interactive effects of elevated CO2 concentration and nitrogen supply on partitioning of newly fixed 13C and 15N between shoot and roots of pedunculate oak seedlings (Quercus robur).
Pedunculate oak (Quercus robur L.) seedlings were grown for 3 or 4 months (second- and third-flush stages) in greenhouses at two atmospheric CO2 concentrations ([CO2]) (350 or 700 micromol mol(-1)) and two nitrogen fertilization regimes (6.1 or 0.61 mmol N l(-1) nutrient solution). Combined effects of [CO2] and nitrogen fertilization on partitioning of newly acquired carbon (C) and nitrogen (N) were assessed by dual 13C and 15N short-term labeling of seedlings at the second- or third-flush stage of development. In the low-N treatment, root growth, but not shoot growth, was stimulated by elevated [CO2], with the result that shoot/root biomass ratio declined. At the second-flush stage, overall seedling biomass growth was increased (13%) by elevated [CO2] regardless of N fertilization. At the third-flush stage, elevated [CO2] increased growth sharply (139%) in the high-N but not the low-N treatment. Root/shoot biomass ratios were threefold higher in the low-N treatment relative to the high-N treatment. At the second-flush stage, leaf area was 45-51% greater in the high-N treatment than in the low-N treatment. At the-third flush stage, there was a positive interaction between the effects of N fertilization and [CO2] on leaf area, which was 93% greater in the high-N/elevated [CO2] treatment than in the low-N/ambient [CO2] treatment. Specific leaf area was reduced (17-25%) by elevated [CO2], whereas C and N concentrations of seedlings increased significantly in response to either elevated [CO2] or high-N fertilization. At the third-flush stage, acquisition of C and N per unit dry mass of leaf and fine root was 51 and 77% greater, respectively, in the elevated [CO2]/high-N fertilization treatment than in the ambient [CO2]/low-N fertilization treatment. However, there was dilution of leaf N in response to elevated [CO2]. Partitioning of newly acquired C and N between shoot and roots was altered by N fertilization but not [CO2]. More newly acquired C and N were partitioned to roots in the low-N treatment than in the high-N treatment.
Topics: Biomass; Carbon Dioxide; Carbon Isotopes; Nitrogen; Nitrogen Isotopes; Plant Roots; Plant Shoots; Quercus; Soil; Trees
PubMed: 11303647
DOI: 10.1093/treephys/21.2-3.163 -
Journal of Agricultural and Food... Jan 2016Oak aging is a crucial step in winemaking during which the organoleptic properties of wine are modified. Various parameters affect the chemical composition of oak wood...
Oak aging is a crucial step in winemaking during which the organoleptic properties of wine are modified. Various parameters affect the chemical composition of oak wood including botanical origin, which has been previously shown to be a determinant factor. This study focused on the development of a LC-HRMS method to assay four recently discovered taste-active triterpenes (three sweet and one bitter). The method was applied to evaluate the effect of oak species (Quercus petraea and Quercus robur) on the concentration of these molecules in wood. The results showed that sessile oak was richer in sweet triterpenes and poorer in the bitter one than pedunculate oak, with high interindividual variations within species. Furthermore, a triterpenoid index was calculated to reveal the triterpenoid composition of oak wood. This index appears to be a promising tool for the unambiguous discrimination of oak species and could offer new insights into oak wood selection by coopers and the monitoring of oak aging by winemakers.
Topics: Chromatography, High Pressure Liquid; Discriminant Analysis; Mass Spectrometry; Quercus; Triterpenes; Wood
PubMed: 26719914
DOI: 10.1021/acs.jafc.5b05056 -
Plant Disease Feb 2010From 2006 to 2008, several similar Phytophthora isolates were obtained from roots of mature Quercus robur and other tree species (Acer platanoides, Fraxinus excelsior,...
From 2006 to 2008, several similar Phytophthora isolates were obtained from roots of mature Quercus robur and other tree species (Acer platanoides, Fraxinus excelsior, Q. rubra, and Tilia cordata) in forests and parks in several areas in the Czech Republic. The trees were characterized by chlorotic and reduced foliage, crown dieback, and reduced root hairs. Several isolates of Phytophthora were obtained from necrotic roots of these trees and identified as Phytophthora plurivora Jung & Burgess (1). Isolated colonies grown on V8A medium were radiate to slightly chrysanthemum shaped with limited aerial mycelium in the center. Optimum growth was at 25°C, minimum at 5°C and maximum at 32°C. Radial growth of colonies averaged 6.4 mm/day at 20°C. The isolates were homothallic and produced abundant smooth-walled, spherical oogonia (23.3 to 29.1 μm in diameter), oospores were nearly plerotic or plerotic (21.8 to 26.9 μm in diameter), and the oospore wall was 1.2 to 1.4 μm thick. Antheridia were usually paragynous and measured 8.4 to 12 × 6.5 to 8 μm, but amphigynous antheridia were occasionally observed. Noncaducous, semipapillate sporangia formed on simple or sympodial sporangiophores, were obpyriform, ovoid, ellipsoid or irregular in shape, and occasionally distorted with more than one apex. Sporangia dimensions were 33 to 65 × 24 to 33 μm; L/B ratio 1.2 to 1.6 (-2.1). Comparison of DNA sequences of internal transcribed spacer (ITS) regions of isolates (representative strain GenBank Accession No. FJ952382) confirmed the 100% identity of P. plurivora (1). The soil infestation test was conducted using a P. plurivora isolate acquired from roots of Q. robur and 20 3-year-old plants of Q. robur. Sterilized millet seeds colonized by pathogen with the method as described (2) were used as inoculation medium and added into sterilized peat substrate at the rate of 0.5% (vol/vol). The plants were cultivated in 5.8-liter pots in a greenhouse (20°C, 16-h/8-h photoperiod). After 4 months, the roots of all plants were washed, dried, and weighed. The root biomass of 20 infected plants was significantly reduced by approximately 25% on average compared with the control 20 plants (P < 0.05, t-test, Statistica 7.1). The pathogen was consistently reisolated from the roots of infected plants but not from control plants. Stem inoculation tests were conducted with 20 replicates in each group of 2-year-old plants of oak, maple, ash, and lime and isolates acquired from the hosts. On each seedling, a 5-mm-diameter bark plug was removed 5 cm above the collar. The inoculum (5-mm-diameter V8A agar plug with actively growing mycelium) was applied to the exposed substrate. The wounds were sealed with Parafilm. Stem necrosis developed in all cases after 1 to 2 weeks, whereas control plants remained healthy. The pathogen was successfully reisolated from necrotic stem tissues. To our knowledge, this is the first report of P. plurivora causing root rot on oak, maple, ash, and lime in the Czech Republic. On the basis of the host range and distribution of P. plurivora in the Czech Republic, it can be assumed that, as elsewhere in Europe (1), this pathogen is widespread and is a common cause of decline of many tree species. References: (1) T. Jung and T. I. Burgess. Persoonia 22:95, 2009. (2) C. Robin et al. Plant Pathol. 50:708, 2001.
PubMed: 30754291
DOI: 10.1094/PDIS-94-2-0272B -
TAG. Theoretical and Applied Genetics.... Dec 1995The restriction patterns of two chloroplast fragments and one mitochondrial DNA fragment, amplified by PCR with universal primers, were studied to determine the mode of...
The restriction patterns of two chloroplast fragments and one mitochondrial DNA fragment, amplified by PCR with universal primers, were studied to determine the mode of inheritance of these organelles in 143 progeny of five intraspecific crosses in pedunculate oak (Quercus robur L.). The results indicate that both genomes are maternally inherited, an observation which agrees with the commonly observed pattern of inheritance in angiosperms. They confirm that both chloroplast DNA and mitochondrial DNA can be used as a source of seed-specific markers for the study of the geographic structure of oaks. This is the first report of organelle inheritance within the Fagaceae, an important and widespread tree family.
PubMed: 24170054
DOI: 10.1007/BF00220937 -
Natural Product Research 2023We tested anti-herpetic effect of castalagin, an ellagitannin compound, extracted from pedunculate oak (). Previous investigations found that castalagin possesses a...
We tested anti-herpetic effect of castalagin, an ellagitannin compound, extracted from pedunculate oak (). Previous investigations found that castalagin possesses a strong inhibitory effect against HSV-1/2 equal to acyclovir (ACV). It is also effective against ACV-resistant mutants and shows a synergistic effect with ACV. We study castalagin's activity towards HSV-1 infection in newborn mice. Acute toxicity determination in mice showed LD value of 295 mg/kg. Prolonged toxicity was also constructed. Castalagin manifested a marked activity against HSV-1 (LD/0.02 ml) administered in 7-day course at 0.02 ml s.c. doses of 7.5 or 10 mg/kg (PI 57-58%). ACV course demonstrated a marked activity at 20 mg/kg. The selectivity ratio LD/ED (295/7.5) could be accepted as ≥ 33.
Topics: Mice; Animals; Herpesvirus 1, Human; Hydrolyzable Tannins; Antiviral Agents; Animals, Newborn; Herpes Simplex; Acyclovir; Herpesvirus 2, Human
PubMed: 36714926
DOI: 10.1080/14786419.2023.2173191 -
TAG. Theoretical and Applied Genetics.... Aug 1996Single-strand conformaiton polymorphism (SSCP) profiles of six PCR-amplified fragments (250-800 bp) were analyzed in three full-sib families of pedunculate oak (Quercus...
Single-strand conformaiton polymorphism (SSCP) profiles of six PCR-amplified fragments (250-800 bp) were analyzed in three full-sib families of pedunculate oak (Quercus robur L.) and their parents. Among the six fragments, four were polymorphic and one exhibited complex patterns that were not changed by varying the SSCP conditions. The number of bands for the analyzed fragments varied between two and four among individuals regardless of fragment size. As shown by segregation data, the variation in the number of bands between trees could only be attributed to the allelic composition (homozygotes vs heterozygotes): a genotype that exhibited two bands was presumptively homozygous, wheras a genotype exhibiting three or four bands was heterozygous. Mendelian proportions were observed in all crosses for each polymorphic fragment. In one cross, we could clearly identify a null allele due to a possible mutation at a primer site. Single-base mutations and short insertion-deletions were shown to be the molecular causes of the SSCP polymorphism observed between different alleles. The use of SSCP as a technique to identify co-dominant markers of PCR fragments (up to 800 bp) is recommended for gene diversity studies or for gene mapping.
PubMed: 24162290
DOI: 10.1007/BF00223175 -
Proceedings. Biological Sciences Sep 2020Insects and pathogens frequently exploit the same host plant and can potentially impact each other's performance. However, studies on plant-pathogen-insect interactions...
Insects and pathogens frequently exploit the same host plant and can potentially impact each other's performance. However, studies on plant-pathogen-insect interactions have mainly focused on a fixed temporal setting or on a single interaction partner. In this study, we assessed the impact of time of attacker arrival on the outcome and symmetry of interactions between aphids (), powdery mildew (), and caterpillars () feeding on pedunculate oak, , and explored how single versus multiple attackers affect oak performance. We used a multifactorial greenhouse experiment in which oak seedlings were infected with either zero, one, two, or three attackers, with the order of attacker arrival differing among treatments. The performances of all involved organisms were monitored throughout the experiment. Overall, attackers had a weak and inconsistent impact on plant performance. Interactions between attackers, when present, were asymmetric. For example, aphids performed worse, but powdery mildew performed better, when co-occurring. Order of arrival strongly affected the outcome of interactions, and early attackers modified the strength and direction of interactions between later-arriving attackers. Our study shows that interactions between plant attackers can be asymmetric, time-dependent, and species specific. This is likely to shape the ecology and evolution of plant-pathogen-insect interactions.
Topics: Animals; Aphids; Ascomycota; Host-Pathogen Interactions; Insecta; Plant Diseases; Quercus
PubMed: 32962544
DOI: 10.1098/rspb.2020.1303 -
The Biological Bulletin Dec 19741. O. mülleri was present on the gills of most crab species in Beaufort Inlet but not on C. sapidus further upriver indicating that salinity is probably a factor...
THE OCCURRENCE, DISTRIBUTION AND ATTACHMENT OF THE PEDUNCULATE BARNACLE OCTOLASMIS MÜLLERI (COKER) ON THE GILLS OF CRABS, PARTICULARLY THE BLUE CRAB. CALLINECTES SAPIDUS RATHBUN.
1. O. mülleri was present on the gills of most crab species in Beaufort Inlet but not on C. sapidus further upriver indicating that salinity is probably a factor controlling the incidence of the barnacle. 2. The distribution of the barnacle on the individual gills of C. sapidus has been analyzed and the factors affecting this distribution discussed. The main factors are the cleaning action of the epipodites and the respiratory flow of the crab. 3. The barnacle settlement stage larva (cyprid) attaches to blue crab gills a short distance in from the gill margin. The orientation of the larva at settlement is a response to the respiratory flow of the crab resulting in the cirral net of the young barnacle facing into the current. 4. The cement apparatus and internal stalk structures of O. mülleri and Lepas anatifera are compared.
PubMed: 29323951
DOI: 10.2307/1540750 -
Scientific Reports Jan 2022Macrobrachium australiense, is one of Australia's most widespread freshwater invertebrates. Although a significant amount of research has been conducted to understand...
Macrobrachium australiense, is one of Australia's most widespread freshwater invertebrates. Although a significant amount of research has been conducted to understand the diversity of crustacean species in Australia, there has been considerably less effort focused on their Temnocephalidae symbionts. The present study aims to identify Temnocephalidae species found in M. australiense, along with determining their impacts on the fitness of their hosts. A total of 54 M. australiense (common Australian river prawn) were examined for evidence of infection with Temnocephalidae species, of which 96.3% showed at least one sign of infection with Temnocephalidae. Due to damage and immaturity of the worms collected from, they have been referred to as Temnocephalidae sp. based on the presence of tentacles on the anterior margin of the body, and pedunculate sucker located dorsally on the ventral surface. Possible mechanical damage to gill lamellae resulting from either egg deposition or autolysis is evident. In the phylogenetic tree built based on sequences of the 28S rRNA gene, specimens in the present study grouped separately from other Temnocephalidae species reported from Australia.
Topics: Animals; Australia; Fresh Water; Gills; Host-Parasite Interactions; Palaemonidae; Phylogeny; Platyhelminths; RNA, Ribosomal, 28S; Symbiosis
PubMed: 35082314
DOI: 10.1038/s41598-022-05123-z -
Phytopathology Aug 2004ABSTRACT Phytophthora cinnamomi is the causal agent of a perennial canker that develops on the lower bole on northern red oak and pedunculate oak. The disease has a...
ABSTRACT Phytophthora cinnamomi is the causal agent of a perennial canker that develops on the lower bole on northern red oak and pedunculate oak. The disease has a limited range in Europe, being reported only in southwest France. This limited distribution is probably linked to the susceptibility of P. cinnamomi to frost. A model was developed in previous work to estimate the impact of temperatures of <0 degrees C on the winter survival of P. cinnamomi in trunk cortical tissues and on the subsequent development of cankers. In this article, we report the use of this model to simulate canker development in 503 locations across France during a 30-year period. The predicted canker extension decreased sharply when the median P. cinnamomi winter survival index decreased from 0.95 to 0.65, with cankers that poorly developed when the median survival index was lower than 0.5 to 0.6. The actual incidence of the disease in 192 stands located across southwest France was compared with that of the model outputs. Both presence of disease in stands and frequency of cankered trees in infected stands, but not canker size on infected trees, were strongly related to the median P. cinnamomi survival index. No disease was present in stands with median survival index lower than 0.65, and the frequency of cankered trees in infected stands remained very low in stands with a median survival index between 0.65 and 0.70. Aspect was an additional factor explaining disease incidence, while the effect of elevation was likely due to its effect on winter temperatures. Maps of winter suitability to P. cinnamomi-induced cankers on oaks in France are presented.
PubMed: 18943102
DOI: 10.1094/PHYTO.2004.94.8.826