WorldWideScience

Sample records for bur oak quercus

  1. Insects of bur oak acorns

    Science.gov (United States)

    Lester P. Gibson

    1971-01-01

    During 1961-1969, the insects found damaging acorns of bur oak, Quercus macrocarpa Michauxii, in their order of importance were the weevils: Curculio pardalis (Chittenden), C. strictus (Casey), C. sulcatulus (Casey), C. iowensis (Casey), C. proboscideus...

  2. Drivers of radial growth and carbon isotope discrimination of bur oak (Quercus macrocarpa Michx.) across continental gradients in precipitation, vapour pressure deficit and irradiance

    Science.gov (United States)

    Steven L. Voelker; Frederick C. Meinzer; Barbara Lachenbruch; J. Renee Brooks; Richard P. Guyette

    2014-01-01

    Tree-ring characteristics are commonly used to reconstruct climate variables, but divergence from the assumption of a single biophysical control may reduce the accuracy of these reconstructions. Here, we present data from bur oaks (Quercus macrocarpa Michx.) sampled within and beyond the current species bioclimatic envelope to identify the primary...

  3. Variation in flood tolerance of container-grown seedlings of swamp white oak, bur oak, and white oak

    Science.gov (United States)

    Michael P. Walsh; J.W. Van Sambeek; Mark V. Coggeshall

    2008-01-01

    How much variation in flood tolerance exists among seedlings within oak species, given the flood frequency of sites from which acorns are collected, has been largely unexplored. Our studies examined initial growth and flood tolerance for seedlings of swamp white oak (Quercus bicolor Willd.), bur oak (Q. macrocarpa L.), and white...

  4. The oak (Quercus) biodiversity of California and adjacent regions

    Science.gov (United States)

    Kevin C. Nixon

    2002-01-01

    Twenty species of oak (Quercus) are known from California. The white oak group is the most diverse, and includes a complex of scrub oak species that are often encountered in chaparral, mixed forest and desert margin habitats. The Protobalanus group (e.g., Quercus chrysolepis) is a unique and distinctive clade of western North...

  5. Molecular diversity among Turkish oaks ( QUERCUS ) using random ...

    African Journals Online (AJOL)

    Here, three species of evergreen oaks known as Quercus coccifera, Quercus ilex and Quercus aucheri were studied in all area located and made the comparison within and among species studied using ten RAPD markers. As a result; it can be stated that the presence of the three species in Ilex section is clear. Furthermore ...

  6. The taxonomic status of the Mexican oak Quercus undata (Fagaceae, Quercus, Section Quercus) El estatus taxonómico del encino mexicano Quercus undata (Fagaceae, Quercus, Sección Quercus)

    OpenAIRE

    Bacon, Jeffrey R.; Patricia Dolores Dávila-Aranda; Richard Spellenberg; M. Socorro González-Elizondo

    2011-01-01

    Quercus undata Trel. (Fagaceae, Quercus, Section Quercus) has a complex taxonomic and nomenclatural history. Intensive sampling of oaks at the type locality of Q. undata Trel. in Durango, Mexico and evaluation of herbarium specimens and plants in the field indicate that Q. undata represents variation in Quercus chihuahuensis Trel. in white oak communities where introgressive hybridization among Q. chihuahuensis, Q. grisea Liebm., and a third white oak, Q. arizonica Sarg. made species identifi...

  7. Evaluation of extractive content in Albanian white oak ( Quercus ...

    African Journals Online (AJOL)

    The extraction is done with Soxhlet 250 ml capacity, for about 6 h. The content of extractives decreased from the base to the top of the tree and their content in wood was 4.7%. This result is near to those recommended in literature for Quercus sp. Key words: Extractives, extraction solvent, Soxhlet, evaporator, white oak.

  8. In vitro propagation of northern red oak (Quercus rubra L.)

    Science.gov (United States)

    G. Vengadesan; Paula M. Pijut

    2009-01-01

    In vitro propagation of northern red oak (Quercus rubra) shoots was successful from cotyledonary node explants excised from 8-wk-old in vitro grown seedlings. Initially, four shoots per explant were obtained on Murashige and Skoog (MS) medium supplemented with 4.4 µM 6-benzylaminopurine (BA), 0.45 ...

  9. Sessile oak (Quercus petraea agg. Ehrendorfer 1967) rare ...

    African Journals Online (AJOL)

    Sessile oak ( Quercus petraea agg. Ehrendorfer 1967) genetic variability in Serbia was estimated applying cpDNA universal primer pairs. Five different haplotypes were detected in the analyzed sample material from populations in Serbia. The areas in West and Southwest Serbia, with all their specificities, represent an ...

  10. The taxonomic status of the Mexican oak Quercus undata (Fagaceae, Quercus, Section Quercus El estatus taxonómico del encino mexicano Quercus undata (Fagaceae, Quercus, Sección Quercus

    Directory of Open Access Journals (Sweden)

    Jeffrey R. Bacon

    2011-12-01

    Full Text Available Quercus undata Trel. (Fagaceae, Quercus, Section Quercus has a complex taxonomic and nomenclatural history. Intensive sampling of oaks at the type locality of Q. undata Trel. in Durango, Mexico and evaluation of herbarium specimens and plants in the field indicate that Q. undata represents variation in Quercus chihuahuensis Trel. in white oak communities where introgressive hybridization among Q. chihuahuensis, Q. grisea Liebm., and a third white oak, Q. arizonica Sarg. made species identification difficult. Endlich's type specimen of Q. undata, as designated by Trelease, was apparently destroyed in bombing raids on Berlin during World War II, and we propose herein as lectotype the Trelease illustration of the type. An epitype is also designated in support of the lectotype, given that some features cannot be critically observed on the illustration. The long peduncles of the specimen illustrated by Trelease indicate a close relation to Q. chihuahuensis.Quercus undata Trel. (Fagaceae, Quercus, Section Quercus tiene una compleja historia taxonómica y de nomenclatura. Un muestreo intensivo de los encinos en la localidad tipo de Q. undata en Durango, México y análisis de ejemplares en herbario y en el campo indican que Q. undata representa variación en Q. chihuahuensis Trel. en los sitios donde la hibridación introgresiva entre Q. chihuahuensis, Q. grisea Liebm., y un tercer encino blanco, Q. arizonica Sarg., dificultan la identificación de especies. El ejemplar tipo designado por Trelease aparentemente fue destruido en el bombardeo de Berlín durante la Segunda Guerra Mundial, por lo que se propone como lectotipo a la ilustración del tipo en la obra de Trelease. Se designa también un epitipo dado que algunos rasgos no pueden ser críticamente observados en la ilustración. Los largos pedúnculos del espécimen ilustrado por Trelease indican la relación cercana a Q. chihuahuensis.

  11. Microsatellite Primer Development for Post Oak, Quercus stellata (Fagaceae

    Directory of Open Access Journals (Sweden)

    Warren B. Chatwin

    2014-10-01

    Full Text Available Premise of the study: The American Cross Timbers forest ecosystem runs from southeastern Kansas to Central Texas and is primarily composed of post oak (Quercus stellata. This old-growth forest currently occupies only about 2% of its ancestral range. To facilitate genetic research on this species, we developed microsatellite primers specific to post oak from reduced genomic libraries. Methods and Results: Two Q. stellata individuals, sampled from the northern and southern range of the post oak forest, were subject to genomic reduction and 454 pyrosequencing. Bioinformatic analysis identified putative microsatellites from which 12 polymorphic primer sets were screened on three populations. The number of alleles observed ranged from five to 20 across all populations, while observed and expected heterozygosity values ranged from 0.05 to 0.833 and 0.236 to 0.893, respectively, within individual populations. Conclusions: We report the development of microsatellite markers, specific to post oak, to aid the study of genetic diversity and population structure of extant forest remnants.

  12. Coast live oak, Quercus agrifolia, susceptibility and response to goldspotted oak borer, Agrilus auroguttatus, injury in southern California

    Science.gov (United States)

    Tom W. Coleman; Nancy E. Grulke; Miles Daly; Cesar Godinez; Susan L. Schilling; Philip J. Riggan; Steven J. Seybold

    2011-01-01

    Oak mortality is often associated with a complex of decline factors. We describe the morphological and physiological responses of coast live oak, Quercus agrifolia Née, in California to an invasive insect, the goldspotted oak borer (GSOB), Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), and evaluate drought as a...

  13. Underplanting to sustain future stocking of oak (Quercus) in temperate deciduous forests

    Science.gov (United States)

    Daniel C. Dey; Emile S. Gardiner; Callie J. Schweitzer; John M. Kabrick; Douglass F. Jacobs

    2012-01-01

    Oaks (Quercus spp.) are one of the most important tree taxa in the northern hemisphere. Although they are dominant in mixed species forests and widely distributed, there are frequent reports of regeneration failures. An adequate population of large oak advance reproduction is a critical prerequisite to successful oak regeneration, and hence...

  14. Growth and Seed Production of Sawtooth Oak (Quercus acutissima) 22 Years After Direct Seeding

    Science.gov (United States)

    J.C.G. Goelz; D.W. Carlson

    1997-01-01

    Sawtooth oak (Quercus acutissima Carruth.) was direct seeded at two locations, one with a poorly drained clay soil and the other with a well-drained silty clay loam. For comparison, Nuttall oak (Q. nuttallii Palmer) was direct seeded on the poorly drained clay soil. On the well-drained silty clay loam, sawtooth oak was 18 ft...

  15. Regeneration patterns of European oak species (Quercus petraea (Matt.) Liebl., Quercus robur L.) in dependence of environment and neighborhood.

    Science.gov (United States)

    Annighöfer, Peter; Beckschäfer, Philip; Vor, Torsten; Ammer, Christian

    2015-01-01

    Quercus robur L. (pedunculate oak) and Quercus petraea (Matt.) Liebl. (sessile oak) are two European oak species of great economic and ecological importance. Even though both oaks have wide ecological amplitudes of suitable growing conditions, forests dominated by oaks often fail to regenerate naturally. The regeneration performance of both oak species is assumed to be subject to a variety of variables that interact with one another in complex ways. The novel approach of this research was to study the effect of many ecological variables on the regeneration performance of both oak species together and identify key variables and interactions for different development stages of the oak regeneration on a large scale in the field. For this purpose, overstory and regeneration inventories were conducted in oak dominated forests throughout southern Germany and paired with data on browsing, soil, and light availability. The study was able to verify the assumption that the occurrence of oak regeneration depends on a set of variables and their interactions. Specifically, combinations of site and stand specific variables such as light availability, soil pH and iron content on the one hand, and basal area and species composition of the overstory on the other hand. Also browsing pressure was related to oak abundance. The results also show that the importance of variables and their combinations differs among the development stages of the regeneration. Light availability becomes more important during later development stages, whereas the number of oaks in the overstory is important during early development stages. We conclude that successful natural oak regeneration is more likely to be achieved on sites with lower fertility and requires constantly controlling overstory density. Initially sufficient mature oaks in the overstory should be ensured. In later stages, overstory density should be reduced continuously to meet the increasing light demand of oak seedlings and saplings.

  16. Physiological Responses to Prolonged Drought Differ Among Three Oak (Quercus) Species

    Science.gov (United States)

    Cooper, C. E.; Moore, G. W.; Vogel, J. G.; Muir, J. P.

    2015-12-01

    The physiological response of plants to water stress provides insights into which species may survive in exceptional drought conditions. This study conducted on a remnant post oak savanna site in College Station, Texas, examined how drought affected the physiology of three native oak species. In June 2014, after a period of equal watering, we subjected three year old Quercus shumardii (Shumard oak; SO), Q. virginiana (live oak; LO), and Q. macrocarpa (bur oak; BO) saplings to one of two watering treatments: 1) watered, receiving the equivalent of theaverage precipitation rate and 2) droughted, receiving a 100% reduction in precipitation. We measured predawn (ΨPD) and midday (ΨMD) leaf water potential; midday gas exchange (MGE) parameters including photosynthesis (Al), transpiration (T), stomatal conductance (gsw); and leaf soluble (SS) and non-soluble sugar (NSS) concentrations monthly between June and October 2014. Drought stress responses were evident after only one month of induced drought. Droughted saplings showed reduced ΨPD, ΨMD, and MGE (P ≤ 0.05) in comparison to watered saplings of the same species. LO saplings exhibited greater MGE (P ≤ 0.05) while maintaining similar LWP to their respective watered and droughted BO and SO counterparts. Droughted LO exhibited MGE rates similar to those of watered BO and SO (P ≤ 0.05), while watered LO adjusted its MGE rates to changes in water availability better than BO and LO during short-term drought. Compared to water saplings, droughted saplings had greater leaf SS (P = 0.08) and lower NSS concentrations (P = 0.10), possibly due to the conversion of NSS to SS and other simple compounds and reduced consumption of SS for growth by the droughted saplings. Although SO and BO exhibited similar photosynthesis rates, leaf total sugar (SS+NSS) concentration was greater in SO (P ≤ 0.05). By displaying the greatest average photosynthesis rate (P ≤ 0.05), LO should have accumulated the greatest amount of carbon

  17. HOW DISCRETE ARE OAK SPECIES? INSIGHTS FROM A HYBRID ZONE BETWEEN QUERCUS GRISEA AND QUERCUS GAMBELII.

    Science.gov (United States)

    Howard, Daniel J; Preszler, Ralph W; Williams, Joseph; Fenchel, Sandra; Boecklen, William J

    1997-06-01

    The white oaks Quercus gambelii and Q. grisea overlap in distribution in New Mexico and Arizona. Within the region of overlap, there are numerous instances of contact between the two taxa. In some areas of contact morphologically, intermediate trees are common, whereas in others, morphologically intermediate trees are rare or absent. We describe a set of RAPD markers that distinguish between the two species and use these markers to examine patterns of gene exchange in an area of contact in the San Mateo Mountains of New Mexico. The markers are highly coincident with morphology and confirm that hybridization between the two species takes place. Despite the occurrence of hybrids, both species remain distinct, even in areas of sympatry, and marker exchange appears to be limited. © 1997 The Society for the Study of Evolution.

  18. Conservation biogeography of red oaks (Quercus, section Lobatae) in Mexico and Central America

    National Research Council Canada - National Science Library

    Andrés Torres-Miranda; Isolda Luna-Vega; Ken Oyama

    2011-01-01

    .... In this study, we analyzed patterns of distribution of red oaks (Quercus, section Lobatae) occurring in Mexico and Central America to determine areas of species richness and endemism to propose areas of conservation. Methods...

  19. Previously unrecorded damage to oak, Quercus spp., in southern California by the goldspotted oak borer, Agrilus coxalis Waterhouse (Coleoptera: Buprestidae)

    Science.gov (United States)

    Tom W. Coleman; Steven Seybold

    2008-01-01

    A new and potentially devastating pest of oaks, Quercus spp., has been discovered in southern California. The goldspotted oak borer, Agrilus coxalis Waterhouse (Coleoptera: Buprestidae), colonizes the sapwood surface and phloem of the main stem and larger branches of at least three species of...

  20. Potential effects of sudden oak death on small mammals and herpetofauna in coast live oak (Quercus agrifolia woodlands

    Science.gov (United States)

    Douglas J. Tempel; William D. Tietje

    2006-01-01

    Within San Luis Obispo County, California, coast live oak (Quercus agrifolia) woodlands provide important habitat for many wildlife species (see Tietje and others, this volume). Unfortunately, many of these woodlands are at high risk of sudden oak death (SOD) infection should the pathogen (Phytophthora ramorum) become established...

  1. Effects of the goldspotted oak borer, Agrilus auroguttatus, on the health of coast live oak, Quercus agrifolia, in southern California before and after treatment with two systemic insecticides

    Science.gov (United States)

    Yigen Chen; Mary L. Flint; Tom W. Coleman; Joseph J. Doccola; Donald M. Grosman; David L. Wood; Steven J. Seybold

    2015-01-01

    The invasive goldspotted oak borer, Agrilus auroguttatus (Coleoptera: Buprestidae), is threatening the health and survival of oak trees in San Diego County, California (Flint and others 2013). The primary oak species colonized and killed in this area include coast live oak (Quercus agrifolia), California black oak (...

  2. The diversification of terpene emissions in Mediterranean oaks: lessons from a study of Quercus suber, Quercus canariensis and its hybrid Quercus afares.

    Science.gov (United States)

    Welter, Saskia; Bracho-Nuñez, Araceli; Mir, Céline; Zimmer, Ina; Kesselmeier, Jürgen; Lumaret, Roselyne; Schnitzler, Jörg-Peter; Staudt, Michael

    2012-09-01

    Interspecific gene flow is common in oaks. In the Mediterranean, this process produced geographical differentiations and new species, which may have contributed to the diversification of the production of volatile terpenes in the oak species of this region. The endemic North African deciduous oak Quercus afares (Pomel) is considered to be a stabilized hybrid between the evergreen Quercus suber (L.) and the deciduous Quercus canariensis (Willd.), presumably being monoterpene and isoprene emitters, respectively. In a common garden experiment, we examined the terpene emission capacities, terpene synthase (TPS) activities and nuclear genetic markers in 52 trees of these three oak species. All but one of the Q. suber and Q. canariensis trees were found to be genetically pure, whereas most Q. afares trees possessed a mixed genotype with a predominance of Q. suber alleles. Analysis of the foliar terpene emissions and TPS activities revealed that all the Q. canariensis trees strongly produced isoprene while all the Q. suber trees were strong monoterpene producers. Quercus afares trees produced monoterpenes as well but at more variable and significantly lower rates, and with a monoterpene pattern different than that observed in Q. suber. Among 17 individuals tested, one Q. afares tree emitted only an insignificant amount of terpenes. No mixed isoprene/monoterpene emitter was detected. Our results suggest that the capacity and pattern of volatile terpene production in Algerian Q. afares populations have strongly diverged from those of its parental species and became quantitatively and qualitatively reduced, including the complete suppression of isoprene production.

  3. A bibliography for Quercus garryana and other geographically associated and botanically related oaks.

    Science.gov (United States)

    Constance A. Harrington; Melanie A. Kallas

    2002-01-01

    Interest in Quercus garryana Dougl. ex Hook., commonly known as Oregon white oak or Garry oak, has increased in recent years as scientists, resource managers, and the general public focus attention on a forest type in decline. To aid those interested in learning what has previously been reported on this species, we have compiled a comprehensive bibliography for Q....

  4. Influence of Soil Type and Drainage on Growth of Swamp Chestnut Oak (Quercus Michauxii Nutt.) Seedlings

    Science.gov (United States)

    Donald D. Hook

    1969-01-01

    Swamp chestnut oak (Quercus michauxii Nutt.) seedlings were grown for 2 years in five soil types in drained and undrained pots. First-year height growth was related to soil type and pot drainage, but second-year height growth was related only to soil type. Results suggest that swamp chestnut oak is site-sensitive. But slow growth, a maximum of 2...

  5. Somatic embryogenesis and plant regeneration of northern red oak (Quercus rubra L.)

    Science.gov (United States)

    G. Vengadesan; Paula M. Pijut

    2009-01-01

    A somatic embryogenesis protocol for plant regeneration of northern red oak (Quercus rubra) was established from immature cotyledon explants. Embryogenic callus cultures were induced on Murashige and Skoog medium (MS) containing 3% sucrose, 0.24% Phytagel™, and various concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) after 4 weeks of...

  6. Whole-transcriptome response to water stress in a California endemic oak, Quercus lobata

    Science.gov (United States)

    Paul F. Gugger; Juan Manuel Peñaloza-Ramírez; Jessica W. Wright; Victoria L. Sork; Jörg-Peter Schnitzler

    2016-01-01

    Reduced water availability during drought can create major stress for many plant species. Within a species, populations with a history of seasonal drought may have evolved the ability to tolerate drought more than those in areas of high precipitation and low seasonality. In this study, we assessed response to water stress in a California oak species, Quercus lobata Née...

  7. Growth and biomass distribution of cherrybark oak (Quercus pagoda Raf.) seedlings as influenced by light availability

    Science.gov (United States)

    Emile S. Gardiner; John D. Hodges

    1998-01-01

    Cherrybark oak (Quercus pagoda Raf.) seedlings were established and raised in the field under four light levels (100 percent. 53 percent, 27 percent or 8 percent of full sunlight) to study the effects of light availability on their shoot growth, biomass accumulation. and biomass distribution. After two growing seasons, greatest stem growth was observed on seedlings...

  8. Underplanting cherrybark oak (Quercus pagoda Raf.) seedlings on a bottomland site in the southern United States

    Science.gov (United States)

    Emile S. Gardiner; Jimmie L. Yeiser

    2006-01-01

    We initiated a study on a bottomland site in the southern United States to examine the effects of Japanese honeysuckle (Lonicera japonica Thunberg) control and seedlings of two root classes on survival and growth of underplanted cherrybark oak (Quercus pagoda Raf.) seedlings. Three honeysuckle control treatments were assigned to...

  9. Photosynthetic light response of flooded cherrybark oak (Quercus pagoda) seedlings grown in two light regimes

    Science.gov (United States)

    Emile S. Gardiner; Ken W. Krauss

    2001-01-01

    Two-year-old cherrybark oak (Quercus pagoda Raf.) seedlings raised in full or partial (27 percent) sunlight were flooded for 30 days to study the effects of light availability and root inundation on photosynthetic light response. Compared with seedlings receiving full sunlight, seedlings receiving partial sunlight developed leaves...

  10. Additivity in tree biomass components of Pyrenean oak (Quercus pyrenaica Willd.)

    Science.gov (United States)

    Joao P. Carvalho; Bernard R. Parresol

    2003-01-01

    In tree biomass estimations, it is important to consider the property of additivity, i.e., the total tree biomass should equal the sum of the components. This work presents functions that allow estimation of the stem and crown dry weight components of Pyrenean oak (Quercus pyrenaica Willd.) trees. A procedure that considers additivity of tree biomass...

  11. Variability of the chloroplast DNA of sessile oak (Quercus petraea agg. Ehrendorfer, 1967 in Serbia

    Directory of Open Access Journals (Sweden)

    Šijačić-Nikolić Mirjana

    2009-01-01

    Full Text Available Genetic variability of sessile oak (Quercus petraea agg. Ehrendorfer, 1967 in Serbia is estimated applying cpDNA universal primer pairs that were characterized by a high informative level for chloroplast genome variability assessment in previous investigations. Five different haplotypes were detected in the analyzed sample material from populations in Serbia.

  12. Interspecific variation in functional traits of oak seedlings (Quercus ilex, Quercus trojana, Quercus virgiliana) grown under artificial drought and fire conditions.

    Science.gov (United States)

    Chiatante, D; Tognetti, R; Scippa, G S; Congiu, T; Baesso, B; Terzaghi, M; Montagnoli, A

    2015-07-01

    To face summer drought and wildfire in Mediterranean-type ecosystems, plants adopt different strategies that involve considerable rearrangements of biomass allocation and physiological activity. This paper analyses morphological and physiological traits in seedlings of three oak species (Quercus ilex, Quercus trojana and Quercus virgiliana) co-occurring under natural conditions. The aim of this study was to evaluate species-specific characteristics and the response of these oak seedlings to drought stress and fire treatment. Seedlings were kept in a growth chamber that mimicked natural environmental conditions. All three species showed a good degree of tolerance to drought and fire treatments. Differences in specific biomass allocation patterns and physiological traits resulted in phenotypic differences between species. In Q. ilex, drought tolerance depended upon adjustment of the allocation pattern. Q. trojana seedlings undergoing mild to severe drought presented a higher photosystem II (PSII) efficiency than control seedlings. Moreover, Q. trojana showed a very large root system, which corresponded to higher soil area exploitation, and bigger leaf midrib vascular bundles than the other two species. Morphological and physiological performances indicated Q. trojana as the most tolerant to drought and fire. These characteristics contribute to a high recruitment potential of Q. trojana seedlings, which might be the reason for the dominance of this species under natural conditions. Drought increase as a result of climate change is expected to favour Q. trojana, leading to an increase in its spatial distribution.

  13. Does habitat matter in an urbanized landscape? The birds of the Garry oak (Quercus garryana) ecosystem of southeastern Vancouver Island

    Science.gov (United States)

    Richard E. Feldman; Pamela G. Krannitz

    2002-01-01

    Garry oak (Quercus garryana) was once a dominant habitat type on southeastern Vancouver Island, British Columbia but urbanization has severely fragmented and reduced its occurrence. This study tests whether bird abundance in remnant patches of Garry oak and adjacent Douglas-fir (Pseudotsuga menziesii) is related to Garry oak volume...

  14. Molecular diversity among Turkish oaks (QUERCUS) using random ...

    African Journals Online (AJOL)

    aykut

    2013-11-06

    Nov 6, 2013 ... Tovar-Sanchez and Oyama, 2004; Olfat and. Pourtahmasi, 2010; Maryam Ardi et al., 2012). Govaerts and Frodin (1998) state that the genus Quercus ... well known that extensive hybridization behaviors may occur among species (Bacilieri et al., 1996; Manos et al., 1999; Samuel, 1999; Jensen et al., 2009;.

  15. Structure of herbivore communities in two oak (Quercus spp.) hybrid zones.

    Science.gov (United States)

    Boecklen, William J; Spellenberg, Richard

    1990-11-01

    We examined patterns of density and species diversity for leaf-mining Lepidopterans and gall-forming Hymenopterans in two oak (Quercus spp.) hybrid zones: Quercus depressipes x Q. rugosa and Q. emoryi x Q. coccolobifolia. In both species complexes, hybrid hosts typically supported significantly lower densities and species diversity of parasites than did parental types. This contradicts the findings of Whitham (1989) that suggested that hybrid hosts may act as parasite sinks both in ecological and evolutionary time. We discuss features of hybrid zones that are likely to influence patterns of herbivory.

  16. Draft genome sequence of the fungus associated with oak-wilt mortality in South Korea, Raffaelea quercus-mongolicae KACC44405

    Science.gov (United States)

    Jongbum Jeon; Ki-Tae Kim; Hyeunjeong Song; Gir-Won Lee; Kyeongchae Cheong; Hyunbin Kim; Gobong Choi; Yong-Hwan Lee; Jane E. Stewart; Ned B. Klopfenstein; Mee-Sook Kim

    2017-01-01

    The fungus Raffaelea quercus-mongolicae is the causal agent of Korean oak wilt, a disease associated with mass mortality of oak trees (e.g., Quercus spp.). The fungus is vectored and dispersed by the ambrosia beetle, Platypus koryoensis. Here, we present the 27.0-Mb draft genome sequence of R. quercus-mongolicae strain KACC44405.

  17. Genotypic variability of morphological characteristics of English oak (Quercus robur L acorn

    Directory of Open Access Journals (Sweden)

    Nikolić Nataša P.

    2002-01-01

    Full Text Available This paper deals with the acorn morphology (length, diameter and mass analyzed in seventeen English oak genotypes (Quercus robur Lfrom the English Oak Clonal Seed Orchard Banov Brod (Srem,Vojvodina. The highest values of acorn mass and length were measured in genotype 5. The largest diameters were measured in genotypes 6 and 21. Genotype 35 had the lowest acorn mass, length and diameter. The results from this study should serve as guidelines for the selection of trees yielding fruits possessing the desirable morphological characteristics.

  18. Influence of Pericarp, Cotyledon and Inhibitory Substances on Sharp Tooth Oak (Quercus aliena var. acuteserrata) Germination

    OpenAIRE

    Yan Liu; Guangquan Liu; Qingmei Li; Yong Liu; Longyu Hou; Guolei Li

    2012-01-01

    In order to explore the mechanism of delayed and uneven germination in sharp tooth oak (Quercus aliena var. acuteserrata) (STO), mechanical scarification techniques were used to study STO root and shoot germination and growth. The techniques used were: removing cup scar (RS), removing the pericarp (RP), and cutting off 1/2 (HC) and 2/3 (TC) cotyledons. Germination percentage and root and shoot length for Chinese cabbage (Beassica pekinensis) seeds (CCS) were also investigated for CCS cultivat...

  19. Myxomycetes from the bark of the evergreen oak Quercus ilex

    Directory of Open Access Journals (Sweden)

    Wrigley de Basanta, Diana

    1998-06-01

    Full Text Available The results of 81 moist chamber cultures of bark from living Quercus ilex trees are reponed. A total of 37 taxa are cited, extending the number of species found on this substrate to 55. The presence of Licea deplanata on the Iberian Península is confirmed. Seven new records are included for the province of Madrid. Some data are contributed on species frequency and incubation times.Se presentan los resultados de 81 cultivos en cámara húmeda de corteza de Quercus ilex vivo. Se citan 37 táxones, que amplían a 55 el número de especies de mixomicetes encontrados sobre este sustrato. Se confirma la presencia en la Península Ibérica de Licea deplanata, y se incluyen siete nuevas citas para la provincia de Madrid. Se aportan datos sobre frecuencia de aparición y tiempos de incubación de algunas especies.

  20. Development of Chloroplast and Nuclear DNA Markers for Chinese Oaks (Quercus Subgenus Quercus and Assessment of Their Utility as DNA Barcodes

    Directory of Open Access Journals (Sweden)

    Jia Yang

    2017-05-01

    Full Text Available Chloroplast DNA (cpDNA is frequently used for species demography, evolution, and species discrimination of plants. However, the lack of efficient and universal markers often brings particular challenges for genetic studies across different plant groups. In this study, chloroplast genomes from two closely related species (Quercus rubra and Castanea mollissima in Fagaceae were compared to explore universal cpDNA markers for the Chinese oak species in Quercus subgenus Quercus, a diverse species group without sufficient molecular differentiation. With the comparison, nine and 14 plastid markers were selected as barcoding and phylogeographic candidates for the Chinese oaks. Five (psbA-trnH, matK-trnK, ycf3-trnS, matK, and ycf1 of the nine plastid candidate barcodes, with the addition of newly designed ITS and a single-copy nuclear gene (SAP, were then tested on 35 Chinese oak species employing four different barcoding approaches (genetic distance-, BLAST-, character-, and tree-based methods. The four methods showed different species identification powers with character-based method performing the best. Of the seven barcodes tested, a barcoding gap was absent in all of them across the Chinese oaks, while ITS and psbA-trnH provided the highest species resolution (30.30% with the character- and BLAST-based methods, respectively. The six-marker combination (psbA-trnH + matK-trnK + matK + ycf1 + ITS + SAP showed the best species resolution (84.85% using the character-based method for barcoding the Chinese oaks. The barcoding results provided additional implications for taxonomy of the Chinese oaks in subg. Quercus, basically identifying three major infrageneric clades of the Chinese oaks (corresponding to Groups Quercus, Cerris, and Ilex referenced to previous phylogenetic classification of Quercus. While the morphology-based allocations proposed for the Chinese oaks in subg. Quercus were challenged. A low variation rate of the chloroplast genome, and

  1. Development of Chloroplast and Nuclear DNA Markers for Chinese Oaks (Quercus Subgenus Quercus) and Assessment of Their Utility as DNA Barcodes

    Science.gov (United States)

    Yang, Jia; Vázquez, Lucía; Chen, Xiaodan; Li, Huimin; Zhang, Hao; Liu, Zhanlin; Zhao, Guifang

    2017-01-01

    Chloroplast DNA (cpDNA) is frequently used for species demography, evolution, and species discrimination of plants. However, the lack of efficient and universal markers often brings particular challenges for genetic studies across different plant groups. In this study, chloroplast genomes from two closely related species (Quercus rubra and Castanea mollissima) in Fagaceae were compared to explore universal cpDNA markers for the Chinese oak species in Quercus subgenus Quercus, a diverse species group without sufficient molecular differentiation. With the comparison, nine and 14 plastid markers were selected as barcoding and phylogeographic candidates for the Chinese oaks. Five (psbA-trnH, matK-trnK, ycf3-trnS, matK, and ycf1) of the nine plastid candidate barcodes, with the addition of newly designed ITS and a single-copy nuclear gene (SAP), were then tested on 35 Chinese oak species employing four different barcoding approaches (genetic distance-, BLAST-, character-, and tree-based methods). The four methods showed different species identification powers with character-based method performing the best. Of the seven barcodes tested, a barcoding gap was absent in all of them across the Chinese oaks, while ITS and psbA-trnH provided the highest species resolution (30.30%) with the character- and BLAST-based methods, respectively. The six-marker combination (psbA-trnH + matK-trnK + matK + ycf1 + ITS + SAP) showed the best species resolution (84.85%) using the character-based method for barcoding the Chinese oaks. The barcoding results provided additional implications for taxonomy of the Chinese oaks in subg. Quercus, basically identifying three major infrageneric clades of the Chinese oaks (corresponding to Groups Quercus, Cerris, and Ilex) referenced to previous phylogenetic classification of Quercus. While the morphology-based allocations proposed for the Chinese oaks in subg. Quercus were challenged. A low variation rate of the chloroplast genome, and complex

  2. Drought-induced photosynthetic inhibition and autumn recovery in two Mediterranean oak species (Quercus ilex and Quercus suber).

    Science.gov (United States)

    Vaz, M; Pereira, J S; Gazarini, L C; David, T S; David, J S; Rodrigues, A; Maroco, J; Chaves, M M

    2010-08-01

    Responses of leaf water relations and photosynthesis to summer drought and autumn rewetting were studied in two evergreen Mediterranean oak species, Quercus ilex spp. rotundifolia and Quercus suber. The predawn leaf water potential (Ψ(lPD)), stomatal conductance (gs) and photosynthetic rate (A) at ambient conditions were measured seasonally over a 3-year period. We also measured the photosynthetic response to light and to intercellular CO₂ (A/PPFD and A/C(i) response curves) under water stress (summer) and after recovery due to autumn rainfall. Photosynthetic parameters, Vc(max), J(max) and triose phosphate utilization (TPU) rate, were estimated using the Farquhar model. RuBisCo activity, leaf chlorophyll, leaf nitrogen concentration and leaf carbohydrate concentration were also measured. All measurements were performed in the spring leaves of the current year. In both species, the predawn leaf water potential, stomatal conductance and photosynthetic rate peaked in spring, progressively declined throughout the summer and recovered upon autumn rainfall. During the drought period, Q. ilex maintained a higher predawn leaf water potential and stomatal conductance than Q. suber. During this period, we found that photosynthesis was not only limited by stomatal closure, but was also downregulated as a consequence of a decrease in the maximum carboxylation rate (Vc(max)) and the light-saturated rate of photosynthetic electron transport (J(max)) in both species. The Vc(max) and J(max) increased after the first autumnal rains and this increase was related to RuBisCo activity, leaf nitrogen concentration and chlorophyll concentration. In addition, an increase in the TPU rate and in soluble leaf sugar concentration was observed in this period. The results obtained indicate a high resilience of the photosynthetic apparatus to summer drought as well as good recovery in the following autumn rains of these evergreen oak species.

  3. Moisture sorption isotherms and thermodynamic properties of Oak wood ( Quercus robur and Quercus canariensis): optimization of the processing parameters

    Science.gov (United States)

    Bahar, Rim; Azzouz, Soufien; Remond, Romain; Ouertani, Sahbi; Elaieb, Mohamed Taher; El Cafci, Mohamed Afif

    2017-05-01

    The aim of this paper was to determine the moisture desorption isotherms and essentials thermodynamic properties of two Oak wood varieties. Desorption isotherms were measured using a static gravimetric method at 50, 60, 70 and 80 °C within the range of 5-90 % relative humidity. The equilibrium moisture content decreased with increasing temperature and decreased with decreasing relative humidity at a constant temperature. The `Thermodynamic' sorption equation was found to be the best for describing the experimental moisture sorption isotherms of woods within the range of temperature and water activity investigated. The Fiber saturation point, deduced from the `Thermodynamic' model parameters, depends on the temperature and varying from 22.6 to 54.4 (% kg water/kg dry matter). Isosteric heat of desorption and differential entropy were calculated by applying Clausius-Clapeyron equation to the desorption data fitted by the `Thermodynamic' model. The isosteric heat of desorption and the differential entropy decreased with increasing moisture content according to an exponential law equation and varying from 2.03 to 31.14 kJ/mol and from 73.98 to 4.34 J/(mol K), respectively. The linear relationship between differential enthalpy and entropy satisfied the enthalpy-entropy compensation theory. The sign of Gibbs free energy was found to be positive (+283 J/mol) and (+97 J/mol) for Quercus robur and Quercus canariensis, respectively. The isokinetic temperature was found to be greater than the harmonic temperature. Based on the enthalpy-entropy compensation theory, it could be concluded that the moisture desorption isotherm of Oak wood is a non-spontaneous and enthalpy-controlled process.

  4. Artificial regeneration of major oak (Quercus) species in the eastern United States - a review of the literature

    Science.gov (United States)

    Daniel C. Dey; Douglass Jacobs; Ken McNabb; Gary W. Miller; V. Baldwin; G. Foster

    2008-01-01

    Although natural regeneration is often the best method for establishing new oak (Quercus spp.) stands, there are increasingly more situations in which high potential for oak regeneration failure dictates the use of artificial regeneration including direct seeding and planting seedlings. Additionally, afforestation planting programs frequently...

  5. Early results from a newly-established provenance test in Valley Oak (Quercus lobata) show significant population differentiation

    Science.gov (United States)

    Jessica W. Wright; Victoria L. Sork

    2017-01-01

    Valley oak (Quercus lobata) is a majestic, endemic California native oak, found throughout California's foothills, valleys and flood plains. It is threatened because: Contracted range due to housing and agriculture.Low recruitment in existing stands as a function of land use and...

  6. Conservation biogeography of red oaks (Quercus, section Lobatae) in Mexico and Central America.

    Science.gov (United States)

    Torres-Miranda, Andrés; Luna-Vega, Isolda; Oyama, Ken

    2011-02-01

    Oaks are dominant trees and key species in many temperate and subtropical forests in the world. In this study, we analyzed patterns of distribution of red oaks (Quercus, section Lobatae) occurring in Mexico and Central America to determine areas of species richness and endemism to propose areas of conservation. Patterns of richness and endemism of 75 red oak species were analyzed using three different units. Two complementarity algorithms based on species richness and three algorithms based on species rarity were used to identify important areas for conservation. A simulated annealing analysis was performed to evaluate and formulate effective new reserves for red oaks that are useful for conserving the ecosystems associated with them after the systematic conservation planning approach. Two main centers of species richness were detected. The northern Sierra Madre Oriental and Serranías Meridionales of Jalisco had the highest values of endemism. Fourteen areas were considered as priorities for conservation of red oak species based on the 26 priority political entities, 11 floristic units and the priority grid-cells obtained in the complementarity analysis. In the present network of Natural Protected Areas in Mexico and Central America, only 41.3% (31 species) of the red oak species are protected. The simulated annealing analysis indicated that to protect all 75 species of red oaks, 12 current natural protected areas need to be expanded by 120000 ha of additional land, and 26 new natural protected areas with 512500 ha need to be created. Red oaks are a useful model to identify areas for conservation based on species richness and endemism as a result of their wide geographic distribution and a high number of species. We evaluated and reformulated new reserves for red oaks that are also useful for the conservation of ecosystems associated with them.

  7. Comparison of palaeobotanical observations with experimental data on the leaf anatomy of durmast oak [Quercus petraea (Fagaceae)] in response to environmental change

    NARCIS (Netherlands)

    Kurschner, W.M; Stulen, G; Wagner, F.; Kuiper, P.J C

    To test whether stomatal density measurements on oak leaf remains are reliable tools for assessing palaeoatmospheric carbon dioxide concentration [CO2], under changing Late Miocene palaeoenvironmental conditions, young seedings of oak (Quercus petraea, Liebl.) were grown at elevated vs. ambient

  8. Symptoms of the naturalisation of the Turkey oak (Quercus cerris L. in Polish forests

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    Danielewicz Władysław

    2016-09-01

    Full Text Available The Turkey oak (Quercus cerris L., the natural range of which embraces southern Europe and Asia Minor, belongs to trees rarely introduced into Polish forests. Tree stands where it appears, established before the Second World War, can be found in some 20 localities, mostly in the western part of the country. Because this species is capable of a natural renewal in a woodland environment, a research was made to find in what conditions and how far it undergoes spontaneous naturalisation. Three study sites were chosen in the forests of central Wielkopolska. An inventory was made of mature stands of the Turkey oak and its generative renewal. Plant communities in which the young generation of Q. cerris usually appears were characterised. It was found that self-sown seedlings of this species grew at a distance of up to 2,500 m from parent trees. The highest number and the greatest density of specimens of the secondary generation of the Turkey oak were found at ‘Racot’, which is a 100-hectare, mid-field woodland island where mesotrophic habitats predominate and where about 50% of the area is occupied by communities with manmade pine tree stands. At all sites, Q. cerris penetrates primarily this type of deformed phytocoenoses, developing mostly on former farmland. It has become a permanent component of the underbrush and undergrowth in them, and in some places, it also makes up the tree layer. It was observed that in the study area, it penetrated the woodland environment much more effectively than Quercus rubra, considered an invasive species. The expansion of the Turkey oak in several of the examined localities can be regarded as a basic manifestation of its naturalisation in places where there are phytocoenoses with pine stands in broad-leaf forest habitats in the neighbourhood of parent trees.

  9. Effects of tornado damage, prescribed fire, and salvage logging on natural oak (Quercus spp.) regeneration in a xeric southern USA Coastal Plain oak/pine forest

    Science.gov (United States)

    Jeffery B. Cannon; J. Stephen Brewer

    2013-01-01

    Due in large part to fire exclusion, many oak-dominated (Quercus spp.) forests, woodlands, and savannas throughout eastern North America are being replaced by less diverse forest ecosystems. In the interior coastal plain of the southern United States, these forests are dominated in the mid- and understory by mesophytic species such as Acer...

  10. Evidence for hybridization and introgression within a species-rich oak (Quercus spp. community

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    Finkeldey Reiner

    2007-11-01

    Full Text Available Abstract Background Analysis of interspecific gene flow is crucial for the understanding of speciation processes and maintenance of species integrity. Oaks (genus Quercus, Fagaceae are among the model species for the study of hybridization. Natural co-occurrence of four closely related oak species is a very rare case in the temperate forests of Europe. We used both morphological characters and genetic markers to characterize hybridization in a natural community situated in west-central Romania and which consists of Quercus robur, Q. petraea, Q. pubescens, and Q. frainetto, respectively. Results On the basis of pubescence and leaf morphological characters ~94% of the sampled individuals were assigned to pure species. Only 16 (~6% individual trees exhibited intermediate morphologies or a combination of characters of different species. Four chloroplast DNA haplotypes were identified in the study area. The distribution of haplotypes within the white oak complex showed substantial differences among species. However, the most common haplotypes were present in all four species. Furthermore, based on a set of 7 isozyme and 6 microsatellite markers and using a Bayesian admixture analysis without any a priori information on morphology we found that four genetic clusters best fit the data. There was a very good correspondence of each species with one of the inferred genetic clusters. The estimated introgression level varied markedly between pairs of species ranging from 1.7% between Q. robur and Q. frainetto to 16.2% between Q. pubescens and Q. frainetto. Only nine individuals (3.4% appeared to be first-generation hybrids. Conclusion Our data indicate that natural hybridization has occurred at relatively low rates. The different levels of gene flow among species might be explained by differences in flowering time and spatial position within the stand. In addition, a partial congruence between phenotypically and genetically intermediate individuals was

  11. Progress report on the evaluation of the susceptibility of the holm oak (Quercus ilex) forest ecosystem to Phytophthora ramorum

    Science.gov (United States)

    Eduardo Moralejo; Enrique Descals

    2006-01-01

    In preliminary studies on the susceptibility of plant members of the holm oak (Quercus ilex) forest, detached leaves of several woody species were highly susceptible when inoculated with zoospore suspensions of local isolates of Phytophthora ramorum (Moralejo and Hernández 2002). Since then, there have been reports of natural...

  12. Rooting stem cuttings of northern red oak (Quercus rubra L.) utilizing hedged stump sprouts formed on recently felled trees

    Science.gov (United States)

    Matthew H. Gocke; Daniel J. Robinson

    2010-01-01

    The ability to root stem cuttings collected from hedged stump sprouts formed on recently felled trees was evaluated for 26 codominant northern red oak (Quercus rubra L.) trees growing in Durham County, NC. Sprouting occurred, the same year as felling, on 23 of the 26 tree stumps and sprout number was significantly and positively correlated with stump diameter. The...

  13. Establishing a range-wide provenance test in valley oak (Quercus lobata Née) at two California sites

    Science.gov (United States)

    Annette Delfino-Mix; Jessica W. Wright; Paul F. Gugger; Christina Liang; Victoria L. Sork

    2015-01-01

    We present the methods used to establish a provenance test in valley oak, Quercus lobata. Nearly 11,000 acorns were planted and 88 percent of those germinated. The resulting seedlings were measured after 1 and 2 years of growth, and were outplanted in the field in the winter of 2014-2015. This test represents a long-term resource for both research...

  14. Recalcitrant Behavior of Cherrybark Oak Seed: An FT-IR Study of Desiccation Sensitivity in Quercus pagoda Raf. Acorns

    Science.gov (United States)

    Sharon Sowa; Kristina F. Connor

    2003-01-01

    The recalcitrant behavior of cherrybark oak (Quercus pagoda Raf.) acorns was examined in terms of effects of moisture content on seed storage longevity and (short term) seed germination. Seed samples collected over two consecutive years were fully hydrated, then subjected to drying under ambient conditions of temperature and relative humidity on the...

  15. Detection of hybrids in nature: application to oaks (Quercus suber and Q. ilex).

    Science.gov (United States)

    Burgarella, C; Lorenzo, Z; Jabbour-Zahab, R; Lumaret, R; Guichoux, E; Petit, R J; Soto, A; Gil, L

    2009-05-01

    Powerful and accurate detection of first-generation (F1) hybrids and backcrosses in nature is needed to achieve a better understanding of the function and dynamics of introgression. To document the frequency of ongoing interspecific gene exchange between two Mediterranean evergreen oaks, the cork oak (Quercus suber) and the holm oak (Q. ilex), we analyzed 1487 individuals originating from across the range of the two species using eight microsatellite loci and two Bayesian clustering approaches (implemented in the programs STRUCTURE and NEWHYBRIDS). Simulated data were used to assess the differences between the two clustering methods and to back up the choice of the threshold value for the posterior probability to discriminate admixed from pure individuals. We found that the use of STRUCTURE resulted in the highest power to detect hybrids, whereas NEWHYBRIDS provided the highest accuracy. Irrespective of the approach, the two species were clearly distinguished as independent genetic entities without any prior information. In contrast with previous reports, we found no evidence for unidirectional introgression. The overall hybridization rate was very low (<2% of introgressed individuals). Only two individuals were identified as F1 hybrids and five as early backcrosses. This work shows that the combined application of the two complementary Bayesian approaches and their systematic validation with simulations, fit for the case at hand, helps gain resolution in the identification of admixed individuals.

  16. Pedunculate oak forests (Quercus robur L. survey in the Ticino Regional Park (Italy by remote sensing

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    Rossini M

    2007-01-01

    Full Text Available Pedunculate oak forests (Quercus robur L. in the Ticino Regional Park (Italy show sensible damage conditions due to different environmental stresses: insect attacks, summer drought and air pollution. Knowing whether oaks are healthy or stressed can provide useful information in order to conserve the forest ecosystems and avoid the lost of valuable natural resources. Environmental stresses can affect tree biochemical and structural variables, such as the concentration, composition and efficiency in light harvesting of foliar pigments, and the Leaf Area Index (LAI. Interest in the use of these variables for forest condition assessment has recently increased because they can be indirectly estimated from remote observations at leaf and canopy level. In particular, in this research we found that total chlorophyll (Chl concentration, a biochemical variable related to crown discoloration rate, was the most suitable variable for the detection of pedunculate oak decline in the Ticino Park. A regression analysis between Chl concentration and optical indices computed from hyperspectral MIVIS data was performed in order to estimate Chl concentration from remote observations. The good correlation between field measurements of Chl concentration and MIVIS optical indices allowed the development of a model to map Chl concentration across the Ticino Park forested area. Promising results demonstrated that remotely sensed data can provide an accurate estimation of Chl concentration and indicated the potential of this technique for forest condition monitoring.

  17. The macrofungal diversity and community of Atlantic oak (Quercus petraea and Q. robur forests in Ireland

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    Harrington, Thomas J.

    2012-06-01

    Full Text Available The oak species Quercus petraea and Q. Robur are dominant canopy tree species of native deciduous forests in Ireland and coastal regions of Western Europe. These forests are typically plant species-rich, and can also have a rich fungal flora. This survey examined macrofungi found in five native oak sites across Ireland over three years. Overall, 94 macrofungal species belonging to 39 genera were discovered with Mycena, Lactarius, Russula and Cortinarius the most species-rich genera. The species accumulation curve did not show signs of levelling off, indicating that more sampling would reveal more new species. Species richness estimation using the Chao2 estimator indicated that up to 135 species may be present across all of our plots, with individual plots receiving estimates from 19 to 61 species per plot. Sampled-based rarefaction analysis showed no significant differences in macrofungal species richness between our plots. The five most common species were Laccaria amethystina, L. laccata, Stereum hirsutum, Armillaria mellea and Cortinarius flexipes. Comparisons of the results with results from oak forests in similar regions found that the communities in Great Britain were most similar to those found in Ireland. There were some key oak forest distinguishing fungal species from the family Boletaceae lacking from Irish oak forests. It is hypothesised that the historic deforestation of Ireland, caused a reduction of suitable habitats for Irish oak associated macrofungi, leading to the unspecific mycota found in the oak forests of this study. The threats to Atlantic oak forests in Ireland are briefly discussed.Las especies de Quercus petraea y Q. Robur se encuentran en bosques de Irlanda y regiones de influencia atlántica de Europa Occidental. Estos bosques, típicamente ricos en especies de plantas, presentan una abundante micobiota. Este estudio examina la diversidad de macromicetes en cinco bosques naturales de roble en Irlanda durante un

  18. Proteotyping of Holm oak (Quercus ilex subsp. ballota) provenances through proteomic analysis of acorn flour.

    Science.gov (United States)

    Galván, José Valero; Fernández, Raquel González; Valledor, Luis; Cerrillo, Rafael Ma Navarro; Jorrin-Novo, Jesus V

    2014-01-01

    Proteomics has become a powerful tool to characterize biodiversity and natural variability in plant species, as well as to catalogue and establish phylogenetic relationships and distances among populations, provenances or ecotypes. In this chapter, we describe the standard proteomics workflow that we currently use in cataloguing Holm oak (Quercus ilex subsp. ballota [Desf.] Samp.) populations. Proteins are extracted from acorn flour or pollen by TCA/acetone or TCA/acetone-phenol methods, resolved by one- or two-dimensional gel electrophoresis, and gel images are captured and analyzed by appropriate software and statistical packages. Quantitative or qualitative variable bands or spots are subjected to MS analysis in order to identify them and correlate differences in the protein profile with the phenotypes or environmental conditions.

  19. Properties of Hungarian oak(quercus conferta Kit. wood from the Hilandar Monastery forest

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    Popović Zdravko

    2007-01-01

    Full Text Available This paper presents the study results of the basic physical and strength properties of Hungarian oak (Quercus conferta Kit. wood from the Kakovo Monastery forests of Hilandar Monastery in Greece. Wood properties were analyzed in detail, as an indispensable proof of wood quality and its use for joinery, interiors and wooden floors. The basic physical properties of wood (moisture content at the time of tree felling, density and volume porosity and the basic strength properties (compressive strength, bending strength and module of elasticity were researched. The results are presented in Tables and in Diagrams with statistical parameters and compared to the literature data. The correlation of the study properties of wood was also analyzed.

  20. Clonal population structure and genetic variation in sand-shinnery oak,Quercus havardii (Fagaceae).

    Science.gov (United States)

    Mayes, S G; McGinley, M A; Werth, C R

    1998-11-01

    We investigated clonal population structure and genetic variation in Quercus havardii (sand-shinnery oak), a deciduous rhizomatous shrub that dominates vegetation by forming uninterrupted expanses of ground cover over sandy deposits on the plains of western Texas, western Oklahoma, and eastern New Mexico. Isozyme electrophoresis (15 loci coding 11 enzymes) was used to recognize and map clones arrayed in a 2000-m transect (50-m sample intervals) and a 200 × 190 m grid (10-m sample intervals). Ninety-four clones were discovered, 38 in the transect and 56 in the grid, resulting in an estimated density of ∼15 clones per hectare. Clones varied greatly in size (∼100-7000 m), shape, and degree of fragmentation. The larger clones possessed massive interiors free of intergrowth by other clones, while the smaller clones varied in degree of intergrowth. The population maintained substantial levels of genetic variation (P = 60%, A = 2.5, H(exp) = 0.289) comparable to values obtained for other Quercus spp. and for other long-lived perennials. The population was outcrossing as evidenced by conformance of most loci to Hardy-Weinberg expected genotype proportions, although exceptions indicated a limited degree of population substructuring. These data indicate that despite apparent reproduction primarily through vegetative means, Q. havardii possesses conventional attributes of a sexual population.

  1. A comparative study of oak (Quercus, Fagaceae) seedling physiology during summer drought in southern California.

    Science.gov (United States)

    Mahall, Bruce E; Tyler, Claudia M; Cole, E Shelly; Mata, Catarina

    2009-04-01

    Natural recruitment of oaks appears to be declining throughout the northern hemisphere. Summer drought poses a potentially important barrier to oak recruitment in southern California. To evaluate this barrier, we grew evergreen Quercus agrifolia and deciduous Q. lobata from seeds near parental trees. We measured water relations, chlorophyll fluorescence, and gas exchange during these seedlings' fourth and fifth summers and compared them to neighboring adults. Most seedlings had substantially lower values for predawn xylem pressure potential (Ψ(pd)), minimum photosystem II (PSII) quantum efficiency (Φ(PSIIMIN)), maximum quantum efficiency for PSII under dark-adapted leaf conditions (Fv/Fm), and maximum photosynthetic assimilation (Amax), and higher values for maximum nonphotochemical quenching (NPQmax) than did conspecific adults. The high, unvarying Ψ(pd) values of the adults suggest they use perennially available groundwater. Quercus lobata seedlings commonly had lower values for Ψ(pd) than did Q. agrifolia, and values for Ψ(pd) and Φ(PSIIMIN) were significantly related to size in Q. lobata but not in Q. agrifolia. These data suggest important interspecific differences in root architecture. Lower values for Φ(PSIIMIN), Fv/Fm, and higher NPQmax in Q. agrifolia indicate that Q. agrifolia seedlings were usually under more stress than Q. lobata, which typically had higher Amax rates than did Q. agrifolia seedlings. Diurnal photosynthesis curves were quite flat for Q. agrifolia, but they peaked in the morning for Q. lobata. Established seedlings appeared to be under more stress than adults, but this stress did not appear severe enough to cause death. Access to perennially available groundwater may be crucial for the seedling to sapling transition.

  2. The increasing sacrcity of red oaks in Mississippi river floodplain forestS: Influence of the residual overstory

    Science.gov (United States)

    Chadwick Dearing Oliver; E.C. Burkhardt; Daniel A. Skojac

    2005-01-01

    Red oaks - cherrybark oak (Quercus pagoda Raf.) willow oak (Quercus phellos L.), water oak (Quercus nigra L.), and Nuttall oak (Quercus texana Buckley; aka: Quercus nuttallii Palmer) - are not regrowing in Mississippi Delta river floodplain forests in the southeastern United...

  3. Comparative Pollen Morphological Analysis and Its Systematic Implications on Three European Oak (Quercus L., Fagaceae) Species and Their Spontaneous Hybrids.

    Science.gov (United States)

    Wrońska-Pilarek, Dorota; Danielewicz, Władysław; Bocianowski, Jan; Maliński, Tomasz; Janyszek, Magdalena

    2016-01-01

    Pollen morphology of three parental Quercus species (Q. robur L., Q. petraea (Matt) Liebl, Q. pubescens Willd.) and two spontaneous hybrids of these species (Q. ×calvescens Vuk. = Q. petraea × Q. pubescens and Q. ×rosacea Bechst. = Q. robur × Q. petraea) was investigated in this study. The pollen originated from 18 natural oak sites and 67 individuals (oak trees). Each individual was represented by 30 pollen grains. In total, 2010 pollen grains were measured. They were analysed for nine quantitative and four qualitative features. Pollen size and shape were important features to diagnosing Quercus parental species and hybrids. On the basis of exine ornamentation, it was possible to identify only Q. pubescens, while the remaining species and hybrids did not differ significantly with respect to this feature. The determination of the diagnostic value of endoaperture features requires further palynological studies. On the basis of pollen size and shape Q. robur × Q. petraea was clearly separated. Grouping of 67 oak trees on the basis of pollen grain features has shown that individuals from different as well as same taxa occurred in the same groups. Likewise, with respect to natural sites, oak trees originating from the same places as well as from geographically distant ones, grouped together. Pollen morphological features allow to distinguish a part of the studied Quercus taxa. Therefore, it can be used as an auxiliary feature in the taxonomy.

  4. Comparative Pollen Morphological Analysis and Its Systematic Implications on Three European Oak (Quercus L., Fagaceae Species and Their Spontaneous Hybrids.

    Directory of Open Access Journals (Sweden)

    Dorota Wrońska-Pilarek

    Full Text Available Pollen morphology of three parental Quercus species (Q. robur L., Q. petraea (Matt Liebl, Q. pubescens Willd. and two spontaneous hybrids of these species (Q. ×calvescens Vuk. = Q. petraea × Q. pubescens and Q. ×rosacea Bechst. = Q. robur × Q. petraea was investigated in this study. The pollen originated from 18 natural oak sites and 67 individuals (oak trees. Each individual was represented by 30 pollen grains. In total, 2010 pollen grains were measured. They were analysed for nine quantitative and four qualitative features. Pollen size and shape were important features to diagnosing Quercus parental species and hybrids. On the basis of exine ornamentation, it was possible to identify only Q. pubescens, while the remaining species and hybrids did not differ significantly with respect to this feature. The determination of the diagnostic value of endoaperture features requires further palynological studies. On the basis of pollen size and shape Q. robur × Q. petraea was clearly separated. Grouping of 67 oak trees on the basis of pollen grain features has shown that individuals from different as well as same taxa occurred in the same groups. Likewise, with respect to natural sites, oak trees originating from the same places as well as from geographically distant ones, grouped together. Pollen morphological features allow to distinguish a part of the studied Quercus taxa. Therefore, it can be used as an auxiliary feature in the taxonomy.

  5. Weak trophic interactions among birds, insects and white oak saplings (Quercus alba)

    Science.gov (United States)

    Lichtenberg, J.S.; Lichtenberg, D.A.

    2002-01-01

    We examined the interactions among insectivorous birds, arthropods and white oak saplings (Quercus alba L.) in a temperate deciduous forest under 'open' and 'closed' canopy environments. For 2 y, we compared arthropod densities, leaf damage and sapling growth. Saplings from each canopy environment were assigned to one of four treatments: (1) reference, (2) bird exclosure, (3) insecticide and (4) exclosure + insecticide. Sap-feeding insects were the most abundant arthropod feeding guild encountered and birds reduced sap-feeder densities in 1997, but not in 1998. Although there was no detectable influence of birds on leaf-chewer densities in either year, leaf damage to saplings was greater within bird exclosures than outside of bird exclosures in 1997. Insecticide significantly reduced arthropod densities and leaf damage to saplings, but there was no corresponding increase in sapling growth. Growth and biomass were greater for saplings in more open canopy environments for both years. Sap-feeder densities were higher on closed canopy than open canopy saplings in 1997, but canopy environment did not influence the effects of birds on lower trophic levels. Although previous studies have found birds to indirectly influence plant growth and biomass, birds did not significantly influence the growth or biomass of white oak saplings during our study.

  6. A 548-Year Tree-Ring Chronology of Oak (Quercus spp.) for Southeast Slovenia and its Significance as a Dating Tool and Climate Archive

    National Research Council Canada - National Science Library

    Katarina Čufar; Martín De Luis; Martin Zupančič; Dieter Eckstein

    2008-01-01

    Tree-ring series of oak, from both living trees (Quercus petraea and Q. robur) and historic timbers in southeastern Slovenia were assembled into a 548-year regional chronology spanning the period A.D. 1456–2003...

  7. Physiological function of insoluble dietary fiber prepared from exploded oak wood (Quercus mongolica).

    Science.gov (United States)

    Yang, Jae-Kyung; Choi, Myung-Suk; Kim, Chang-Joon; Shin, Yong-Seung; Han, Dae-Yong; Han, Sang-Woo; Lim, Bu-Kug; Lee, Jong-Yoon; Rhee, Soon-Jae; Kim, Eun-Hee; Kim, Gon-Sup

    2006-01-01

    This study investigated the production of insoluble dietary fiber using exploded and chemically treated oak wood (Quercus mongolica) and the physiological functions of prepared insoluble dietary fiber in laboratory animals. To produce high quality insoluble dietary fiber, the steam explosion treatment was performed at 25 kgf/cm2 pressure for 6 minutes. In the chemical analysis of insoluble dietary fiber, exploded oak wood was pretreated by 1% sodium hydroxide solution. The insoluble dietary fiber contained 7.6% residual lignin and 61.7% of alpha-cellulose. In order to compare the physiological functions of prepared insoluble dietary fiber with those of commercial insoluble dietary fiber, Sprague-Dawley male rats weighing 100 +/- 10 g were randomly assigned to one normal diet and five high cholesterol diets, containing 1% cholesterol. The high cholesterol diet groups were classified as the fiber-free diet (FF group), 5% commercial alpha-cellulose diet group (5C group), 10% commercial alpha-cellulose group (10C group), 5% insoluble dietary fiber group (5M group) and 10% insoluble dietary fiber group (10M group). Food intake, weight gain and food efficiency ratio in high cholesterol groups were significantly higher than those of the normal group, but there were no significant differences among the high cholesterol diet groups. In addition, there were no significant differences in the weights of liver, kidney and small intestine in insoluble dietary fiber-supplemented groups. Cecum weights in all insoluble dietary fiber groups were significantly higher than those of the FF group. There were no significant differences in the activities of the glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT) among the insoluble dietary fiber-supplemented groups. In conclusion, the prepared insoluble dietary fiber and the commercially available insoluble fiber showed the same physiological effects. Moreover, the preparation method for the insoluble dietary

  8. Lichens of red oak Quercus rubra in the forest environment in the Olsztyn Lake District (NE Poland

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    Dariusz Kubiak

    2013-12-01

    Full Text Available A list of 63 species of lichens and 4 species of lichenicolous fungi recorded on the bark of red oak (Quercus rubra L. in Poland is given. Literature data and the results of field studies conducted in the forest in the Olsztyn Lake District between 1999 and 2005 are used in the report. Fifty-five taxa, including lichens rare in Poland, for instance Lecanora albella, Lecidella subviridis, Ochrolechia turneri, were recorded.

  9. Effects of cadmium on cork oak (Quercus suber L.) plants grown in hydroponics.

    Science.gov (United States)

    Gogorcena, Yolanda; Larbi, Ajmi; Andaluz, Sofia; Carpena, Ramón O; Abadía, Anunciación; Abadía, Javier

    2011-12-01

    Cork oak (Quercus suber L.) is an autochthonous tree species that is being used for reforestation in heavy-metal-contaminated areas in Spain. A hydroponics experiment was carried out to characterize the effects of Cd on several morphological and physiological parameters in this species, including shoot length, nutrient concentrations and allocation in different organs, leaf pigment concentrations, photosynthetic efficiency, root ferric chelate reductase (FCR) activity and organic acid concentrations in xylem sap. Four different Cd treatments were applied, adding Cd chelated with EDTA or as chloride salt at two different concentrations (10 and 50 µM Cd). After 1 month of Cd treatment, plant growth was significantly inhibited in all treatments. Results indicate that Cd accumulates in all organs 7- to 500-fold when compared with control plants. The highest Cd concentration was found in the 50 µM CdCl(2) treatment, which led to concentrations of ~30, 123 and 1153 µg Cd g(-1) dry weight in leaves, stems and roots, respectively. In the strongest Cd treatments the concentrations of P and Ca decreased in some plant parts, whereas the Mn leaf concentrations decreased with three of the four Cd treatments applied. The concentrations of chlorophyll and carotenoids on an area basis decreased, whereas the (zeaxanthin plus antheraxanthin)/(total violaxanthin cycle carotenoids) ratio and the non-photochemical quenching increased significantly in all Cd treatments. Cadmium treatments caused significant increases in the activity of the enzyme FCR in roots and in the concentrations of organic acids in xylem sap. Some of the physiological changes found support the fact that Cd induces a deficiency of Fe in cork oak, although the plant Fe concentrations were not reduced significantly. At higher concentrations the effects of Cd were more pronounced, and were more marked when Cd was in the free ion form than when present in the form of Cd-EDTA.

  10. The Occurrence of Charcoal Disease Caused by Biscogniauxia mediterranea on Chestnut-Leaved Oak (Quercus castaneifolia) in the Golestan Forests of Iran

    NARCIS (Netherlands)

    Mirabolfathy, M.; Groenewald, J.Z.; Crous, P.W.

    2011-01-01

    The chestnut-leaved oak (Quercus castaneifolia) is native to the Alborz Mountains, including the Golestan Forests, in northern Iran. Trees grow up to 35 (-50) m tall with a trunk up to 2.5 (-3.5) m in diameter. During 2010, we received reports of a decline of oak trees in the Ghorogh Region of the

  11. Nutrients and trace elements content of wood decay fungi isolated from oak (Quercus ilex).

    Science.gov (United States)

    Campos, Juan A

    2011-12-01

    The presence of chemical elements and the differences in their concentration in the fruiting bodies of wood decay fungi may reflect their activity either as saprobes or parasites and the intimate physiological relation with the substrate from which they extract their nutrients. In order to test this hypothesis, we carried out a systematic sampling of eight species of wood decay fungi on oak (Quercus ilex). The data show that the concentration of some elements exhibits a very wide range of values for the species tested, which could mean that the relative content of some elements may provide clues about the nature of the substrate and, moreover, about the nutritional physiology. The comparison between the foliar analysis (FA) and the elemental content of fungi may shed light on the specific physiological behaviour of the species. Potassium is an element accumulated in fungal biomass in higher quantities than in the FA. By contrast, calcium appears in foliar analysis in much higher quantities than in fungal fruiting bodies' biomass. Concerning this element, we have also found profound differences between the two species phylogenetic groups and lifestyle. Of all elements measured, we believe that the relative accumulation of K and Ca may be related to the close connection between fungi and the substrate on which they live and may also explain their physiological role as saprobes or parasites. When the lifestyle and the systematic position of the different species sampled were compared, differences also emerged in the content of Na and Ca.

  12. Temporal variations in PAH concentrations in Quercus ilex L. (holm oak) leaves in an urban area.

    Science.gov (United States)

    De Nicola, Flavia; Maisto, Giulia; Prati, Maria Vittoria; Alfani, Anna

    2005-10-01

    Temporal variations of polycyclic aromatic hydrocarbon (PAH) concentrations in leaves of a Mediterranean evergreen oak, Quercus ilex L., were investigated in order to assess the suitability of this species to biomonitor PAH air contamination. Leaf samples were collected at six sites of the urban area of Naples (Italy) and at a control site in the Vesuvius National Park, in May and September 2001, and in January and May 2002. PAH extraction was conducted by sonication in dichloromethane-acetone and quantification by GC-MS. In winter, leaf total PAH concentrations showed, at all the urban sites, values 2-fold higher than in all the other samplings, reflecting the temporal trend reported for PAH air contamination in the Naples urban area. Moreover, leaf PAH concentrations showed, at all the urban sites, a decrease in May 2002 after the winter accumulation. At the control site leaf PAH concentrations showed lower values and smaller temporal variations than at the urban sites. The findings support the suitability of Q. ilex leaves to monitor temporal variations in PAH contamination. The highest winter concentrations of total PAHs were due to the medium molecular weight PAHs that increased with respect to both low and high molecular weight PAHs. The medium molecular weight PAHs showed the same temporal trend both at the urban and remote sites.

  13. Cheiracanthium ilicis sp. n. (Araneae, Eutichuridae), a novel spider species associated with Holm Oaks (Quercus ilex).

    Science.gov (United States)

    Morano, Eduardo; Bonal, Raul

    2016-01-01

    We describe a novel species Cheiracanthium ilicis sp. n. (Araneae, Eutichuridae) collected in the province of Toledo (Central Spain). It was found during a systematic sampling campaign carried out in an agricultural landscape with isolated Holm oaks Quercus ilex and small forest patches. Its morphology and affinities with other species of the genus are discussed. Furthermore, one mitochondrial gene was sequenced to confirm species membership and its differentiation from other Cheiracanthium species. The molecular phylogenies based on mitochondrial and nuclear genes showed a close relationship of Cheiracanthium ilicis sp. n. with Cheiracanthium inclusum and Cheiracanthium mildei, with which it also shares morphological similarities. Nonetheless, the sparse sampling of the phylogeny, due to the low number of sequences available, impedes drawing any definitive conclusion about these relationships; it is first necessary to perform an extensive review of the genus worldwide and more thorough phylogenies. Cheiracanthium ilicis sp. n. also shares certain ecological and phenological characteristics with Cheiracanthium inclusum and Cheiracanthium mildei. Like them, Cheiracanthium ilicis sp. n. is an obligate tree dweller that prefers a tree canopy habitat and reproduces primarily in late spring and summer. From a conservation perspective, the present study suggests the need to preserve isolated trees in agricultural landscapes. They are not only the refuge of common forest organisms but also of novel species yet to be discovered.

  14. Spring temperature responses of oaks are synchronous with North Atlantic conditions during the last deglaciation

    Science.gov (United States)

    Steven L. Voelker; Paul-Emile Noirot-Cosson; Michael C. Stambaugh; Erin R. McMurry; Frederick C. Meinzer; Barbara Lachenburch; Richard P. Guyette

    2012-01-01

    Paleoclimate proxies based on the measurement of xylem cell anatomy have rarely been developed across the temperature range of a species or applied to wood predating the most recent millennium. Here we describe wood anatomy-based proxies for spring temperatures in central North America from modern bur oaks (Quercus macrocarpa Michx.). The strong...

  15. Holm Oak (Quercus ilex L.) canopy as interceptor of airborne trace elements and their accumulation in the litter and topsoil.

    Science.gov (United States)

    Fantozzi, Federica; Monaci, Fabrizio; Blanusa, Tijana; Bargagli, Roberto

    2013-12-01

    We investigated the role of urban Holm Oak (Quercus ilex L.) trees as an airborne metal accumulators and metals' environmental fate. Analyses confirmed Pb, Cd, Cu and Zn as a main contaminants in Siena's urban environment; only Pb concentrations decreased significantly compared to earlier surveys. Additionally, we determined chemical composition of tree leaves, litter and topsoil (underneath/outside tree crown) in urban and extra-urban oak stands. Most notably, litter in urban samples collected outside the canopy had significantly lower concentrations of organic matter and higher concentrations of Pb, Cu, Cd and Zn than litter collected underneath the canopy. There was a greater metals' accumulation in topsoil, in samples collected under the tree canopy and especially near the trunk ('stemflow area'). Thus, in urban ecosystems the Holm Oak stands likely increase the soil capability to bind metals. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Anti nutritional evaluation of the flour of the nipples of holm oak (quercus ilex) and oak cork (quercus suber) Raw and pressure-sealed

    Energy Technology Data Exchange (ETDEWEB)

    El Mahi, F. Z.

    2009-07-01

    The present study contributes to the development of the food potential of the nipples of oak like new resources likely to be exploited on an industrial scale for their use in animal feeds. Our work relates to two species S of nipples of oak, edible, the homl oak and the other fodder one, the oal cork known for their spontaneousness and their vey significant geographical distribution. (Author)

  17. Biodegradation of oak (Quercus alba) wood during growth of the shiitake mushroom (Lentinula edodes): a molecular approach.

    Science.gov (United States)

    Vane, Christopher H; Drage, Trevor C; Snape, Colin E

    2003-02-12

    The chemical transformations that occur during growth of the shiitake mushroom (Lentinula edodes) on oak (Quercus alba) were investigated to improve mushroom cultivation and utilization of the spent substrate. Oak logs were decayed by L. edodes over 8 years, during which time they were sampled at six intervals (30, 40, 66, 76, 77, and 101 months). Fresh and decayed oak samples were analyzed using solid-state (13)C NMR and pyrolysis-gas chromatography-mass spectrometry as well as off-line thermochemolysis with tetramethylammonium hydroxide. Degraded oak exhibited lower carbon contents and increased oxygen content compared to the control. Solid-state (13)C NMR analysis revealed that polysaccharides were the major component of both fresh and decayed oak but that L. edodes mediated the preferential loss of cellulose and xylans as compared to lignin, which remained in an altered form. Several trends point toward the degradation of lignin, including a decrease in the proportion of syringyl units as compared to guaiacyl units and a reduction in side-chain length. An increase in guaiacyl and syringyl acid-to-aldehyde ratios occurred with growth, which suggested that the fungus had caused oxidation of Calpha-Cbeta bonds. The overall effect of L. edodes on oak is similar to that of many white-rot fungi, which simultaneously degrade all cell wall components.

  18. Removal of acorns of the alien oak Quercus rubra on the ground by scatter-hoarding animals in Belgian forests

    Directory of Open Access Journals (Sweden)

    Merceron, NR.

    2017-01-01

    Full Text Available Description of the subject. Quercus rubra L. is considered an invasive species in several European countries. However, little is known about its dispersal in the introduced range. Objectives. We investigated the significance of animal dispersal of Q. rubra acorns on the ground by vertebrates in its introduced range, and identified the animal species involved. Method. During two consecutive autumns, the removal of acorns from Q. rubra and from a native oak was assessed weekly in forest sites in Belgium. We used automated detection camera traps to identify the animals that removed acorns. Results. Quercus rubra acorns were removed by wood mice (Apodemus sylvaticus L., red squirrels (Sciurus vulgaris L., rats (Rattus sp., and wild boars (Sus scrofa L.. The two former are scatter-hoarding rodents and can be considered potential dispersers. Conclusions. Dispersal of Q. rubra acorns in Western Europe by scatter-hoarding animals may help the species increasingly colonize forest ecosystems.

  19. Development of molecular markers for determining continental origin of wood from White Oaks (Quercus L. sect. Quercus)

    Science.gov (United States)

    Hilke Schroeder; Richard Cronn; Yulai Yanbaev; Tara Jennings; Malte Mader; Bernd Degen; Birgit Kersten; Dusan Gomory

    2016-01-01

    To detect and avoid illegal logging of valuable tree species, identification methods for the origin of timber are necessary. We used next-generation sequencing to identify chloroplast genome regions that differentiate the origin of white oaks from the three continents; Asia, Europe, and North America. By using the chloroplast genome of Asian Q. mongolica...

  20. De novo post-illumination monoterpene burst in Quercus ilex (holm oak).

    Science.gov (United States)

    Srikanta Dani, K G; Marino, Giovanni; Taiti, Cosimo; Mancuso, Stefano; Atwell, Brian J; Loreto, Francesco; Centritto, Mauro

    2017-02-01

    Explicit proof for de novo origin of a rare post-illumination monoterpene burst and its consistency under low O 2 , shows interaction of photorespiration, photosynthesis, and isoprenoid biosynthesis during light-dark transitions. Quercus ilex L (holm oak) constitutively emits foliar monoterpenes in an isoprene-like fashion via the methyl erythritol phosphate (MEP) pathway located in chloroplasts. Isoprene-emitting plants are known to exhibit post-illumination isoprene burst, a transient emission of isoprene in darkness. An analogous post-illumination monoterpene burst (PiMB) had remained elusive and is reported here for the first time in Q. ilex. Using 13 CO 2 labelling, we show that PiMB is made from freshly fixed carbon. PiMB is rare at ambient (20%) O 2 , absent at high (50%) O 2 , and becomes consistent in leaves exposed to low (2%) O 2 . PiMB is stronger and occurs earlier at higher temperatures. We also show that primary and secondary post-illumination CO 2 bursts (PiCO 2 B) are sensitive to O 2 in Q. ilex. The primary photorespiratory PiCO 2 B is absent under both ambient and low O 2 , but is induced under high (>50%) O 2 , while the secondary PiCO 2 B (of unknown origin) is absent under ambient, but present at low and high O 2 . We propose that post-illumination recycling of photorespired CO 2 competes with the MEP pathway for photosynthetic carbon and energy, making PiMB rare under ambient O 2 and absent at high O 2 . PiMB becomes consistent when photorespiration is suppressed in Q. ilex.

  1. French Oak Wood (Quercus robur) Extract (Robuvit) in Primary Lymphedema: A Supplement, Pilot, Registry Evaluation

    Science.gov (United States)

    Belcaro, Gianni; Dugall, Mark; Hu, Shu; Ledda, Andrea; Ippolito, Edmondo

    2014-01-01

    The aim of this pilot supplement study was the evaluation of an oak wood extract (Robuvit, Quercus robur [QR], Horphag Research) in an 8-week registry study on lymphatic signs in primary lymphedema. Subjects with primary lymphedema confined to a single leg without skin changes or ulcerations were followed for at least 8 weeks. Lymphedema was mainly present distally (below the knee). Three groups were formed: one group used only the standard management for lymphedema; one used the same management plus 300 mg Robuvit; and one used the standard management plus 600 mg of Robuvit. The three groups were comparable. After 8 weeks the variation in leg volume was on average −6.2% with standard management, −15% in the QR 300 mg group, and −18.9% in the 600 mg group. The edema score was also significantly lower at 8 weeks in the two QR groups. The variation in proteins in the interstitial fluid in comparison with initial values was −14.8% in controls in comparison with −29.9% in QR 300 mg group and −36.9% in QR 600 mg group. Skin flux significantly improved (increased) in the two QR groups. Ultrasound pretibial skin thickness was decreased on average 6% in controls versus 10.3% in the low-dose QR group and 11.8% in the higher dose group. Perimalleolar thickness was decreased 7% in controls and more in the two QR groups. Ankle circumference was decreased 4.4% in controls and more in the two supplement groups. This pilot registry indicates that Robuvit can be effective in the management of primary lymphedema. More patients and longer evaluation periods are needed. PMID:25780327

  2. Spatiotemporal variation in acorn production and damage in a Spanish holm oak (Quercus ilex dehesa

    Directory of Open Access Journals (Sweden)

    L. Perez Izquierdo

    2013-04-01

    Full Text Available Aim of study. There is a lack of knowledge about spatio-temporal patterns of acorn production in dehesas, especially regarding the influence of different agents causing acorn damage. We examined the spatial and temporal variability on acorn production and damage in four stands within a dehesa farm in 1997, 1998 and 1999.Area of study. The study was carried out in a 1800 ha dehesa farm of Cáceres province, western Spain.Material and Methods. Acorns were sampled by means of seed traps placed in the canopy of six holm oak trees per stand. Acorn collected in it were counted and assessed for damage by Curculio weevils, Cydia moths and the bacterial pathogen Brenneria quercina.Main results. Mean acorn production for the whole study period was 44.60 acorns m-2, which did not vary significantly either among stands or among years. The variability among individual trees was very high (0-300 acorns m-2. The rate of infestation by Curculio was 7.64 ± 10.72 %, by Cydia was 1.76 ± 3.33 %, whereas 10.29 ± 16.12 % of acorns were infested by Brenneria. We found no significant spatial differences, but the rates of acorn loss by insects varied among years. These rates were independent of annual acorn production and there was no correlation among damages by different pests, except between Curculio and Cydia in two crop years.Research highlights. It can be concluded that acorn crops are synchronized at the within-farm level and that the temporal variation in acorn damages can be independent of crop size.Keywords: Acorn production; Brenneria; Curculio; Cydia; dehesa; Quercus ilex; spatio-temporal variation.

  3. New approaches to the biogeography and areas of endemism of red oaks (Quercus L., section Lobatae).

    Science.gov (United States)

    Torres-Miranda, Andrés; Luna-Vega, Isolda; Oyama, Ken

    2013-07-01

    An area of endemism is defined by the spatial congruence among two or more species with distributions that are limited by barriers. In this study, we explored and discussed the use of the network analysis method (NAM) and neighbor-joining (NJ) to analyze the areas of endemism of Quercus sect. Lobatae (red oak species) in Mexico and Central America. We compared the NAM and NJ with other methods commonly used in biogeographic studies to show the advantages of these new approaches and to identify the shortcomings of other approaches. The NAM used in this study is based on notions of centrality measures, such as betweenness. We incorporated the strength of the ties within the internal networks through p-cores and aggregate constraints in iterative analyses. The NAM based on betweenness is ideal for recognizing completely allopatric areas of endemism. The iterative NAMs increase the number of possible areas of endemism because they minimize the effect of minimal overlap, and the p-core is efficient at identifying the closest relationships among species in the cases in which betweenness is not informative. The number of areas of endemism increases when the sympatry matrix minimizes the dispersal effect and the sample effort is maximized, allowing the identification of the greatest number of these areas. The NJ method supports the idea that areas diverge among themselves in a differential way; the long branches correspond to zones with high speciation rates and complex histories (biotic and tectonic), and the short branches correspond to zones with low speciation rates and simple histories. In a classification scheme, NJ was capable of identifying the areas that are considered biotically complex because of their high speciation rates. The results obtained with the NAM and NJ showed that the physiographic regions of Mexico are not natural units and that many of them are composed of at least two different biotic components.

  4. Influence of pericarp, cotyledon and inhibitory substances on sharp tooth oak (Quercus aliena var. acuteserrata germination.

    Directory of Open Access Journals (Sweden)

    Yan Liu

    Full Text Available In order to explore the mechanism of delayed and uneven germination in sharp tooth oak (Quercus aliena var. acuteserrata (STO, mechanical scarification techniques were used to study STO root and shoot germination and growth. The techniques used were: removing cup scar (RS, removing the pericarp (RP, and cutting off 1/2 (HC and 2/3 (TC cotyledons. Germination percentage and root and shoot length for Chinese cabbage (Beassica pekinensis seeds (CCS were also investigated for CCS cultivated in a Sanyo growth cabinet watered by distilled water and 80% methanol extracts from the acorn embryo, cotyledon and pericarp with concentrations of 1.0 g, 0.8 g, 0.6 g and 0.4 g dry acorn weight per ml methanol. The results showed that the majority of roots and shoots from acorns with RP and HC treatment emerged two weeks earlier, more simultaneously, and their total emergencies were more than 46% and 28% higher, respectively. TC accelerated root and shoot emergence time and root length, but root and shoot germination rate and shoot height had no significant difference from the control. Positive consequences were not observed on all indices of RS treatment. The germination rates of CCS watered by 1.0 g · ml(-1 methanol extracts from the embryo and cotyledon were significantly lower than those from the pericarp, and all concentrations resulted in decreased growth of root and shoot. Methanol extracts from pericarp significantly reduced root length of CCS, but presented little response in germination percentage and shoot length. The inhibitory effect was gradually increased with the increasing concentration of the methanol extract. We conclude that both the mechanical restriction of the pericarp and the presence of germination inhibitors in the embryo, cotyledon and pericarp are the causes for delayed and asynchronous germination of STO acorns.

  5. Influence of pericarp, cotyledon and inhibitory substances on sharp tooth oak (Quercus aliena var. acuteserrata) germination.

    Science.gov (United States)

    Liu, Yan; Liu, Guangquan; Li, Qingmei; Liu, Yong; Hou, Longyu; Li, Guolei

    2012-01-01

    In order to explore the mechanism of delayed and uneven germination in sharp tooth oak (Quercus aliena var. acuteserrata) (STO), mechanical scarification techniques were used to study STO root and shoot germination and growth. The techniques used were: removing cup scar (RS), removing the pericarp (RP), and cutting off 1/2 (HC) and 2/3 (TC) cotyledons. Germination percentage and root and shoot length for Chinese cabbage (Beassica pekinensis) seeds (CCS) were also investigated for CCS cultivated in a Sanyo growth cabinet watered by distilled water and 80% methanol extracts from the acorn embryo, cotyledon and pericarp with concentrations of 1.0 g, 0.8 g, 0.6 g and 0.4 g dry acorn weight per ml methanol. The results showed that the majority of roots and shoots from acorns with RP and HC treatment emerged two weeks earlier, more simultaneously, and their total emergencies were more than 46% and 28% higher, respectively. TC accelerated root and shoot emergence time and root length, but root and shoot germination rate and shoot height had no significant difference from the control. Positive consequences were not observed on all indices of RS treatment. The germination rates of CCS watered by 1.0 g · ml(-1) methanol extracts from the embryo and cotyledon were significantly lower than those from the pericarp, and all concentrations resulted in decreased growth of root and shoot. Methanol extracts from pericarp significantly reduced root length of CCS, but presented little response in germination percentage and shoot length. The inhibitory effect was gradually increased with the increasing concentration of the methanol extract. We conclude that both the mechanical restriction of the pericarp and the presence of germination inhibitors in the embryo, cotyledon and pericarp are the causes for delayed and asynchronous germination of STO acorns.

  6. Red Oak (Quercus rubra, L.) acron collection, nursery culture and direct seeding: A literature review

    Science.gov (United States)

    Daniel C. Dey

    1995-01-01

    The artificial regeneration of red oak by planting or direct seeding is an important method for restoring oak in ecosystems where it has been lost as a result of past management practices. Planting and direct seeding can also be used to supplement natural oak regeneration and to ensure that sufficient oak reproduction is in place when overstories are removed through...

  7. Development of Molecular Markers for Determining Continental Origin of Wood from White Oaks (Quercus L. sect. Quercus).

    Science.gov (United States)

    Schroeder, Hilke; Cronn, Richard; Yanbaev, Yulai; Jennings, Tara; Mader, Malte; Degen, Bernd; Kersten, Birgit

    2016-01-01

    To detect and avoid illegal logging of valuable tree species, identification methods for the origin of timber are necessary. We used next-generation sequencing to identify chloroplast genome regions that differentiate the origin of white oaks from the three continents; Asia, Europe, and North America. By using the chloroplast genome of Asian Q. mongolica as a reference, we identified 861 variant sites (672 single nucleotide polymorphisms (SNPs); 189 insertion/deletion (indel) polymorphism) from representative species of three continents (Q. mongolica from Asia; Q. petraea and Q. robur from Europe; Q. alba from North America), and we identified additional chloroplast polymorphisms in pools of 20 individuals each from Q. mongolica (789 variant sites) and Q. robur (346 variant sites). Genome sequences were screened for indels to develop markers that identify continental origin of oak species, and that can be easily evaluated using a variety of detection methods. We identified five indels and one SNP that reliably identify continent-of-origin, based on evaluations of up to 1078 individuals representing 13 white oak species and three continents. Due to the size of length polymorphisms revealed, this marker set can be visualized using capillary electrophoresis or high resolution gel (acrylamide or agarose) electrophoresis. With these markers, we provide the wood trading market with an instrument to comply with the U.S. and European laws that require timber companies to avoid the trade of illegally harvested timber.

  8. Tree species richness, diversity, and regeneration status in different oak (Quercus spp. dominated forests of Garhwal Himalaya, India

    Directory of Open Access Journals (Sweden)

    Sushma Singh

    2016-09-01

    Full Text Available Himalayan forests are dominated by different species of oaks (Quercus spp. at different altitudes. These oaks are intimately linked with hill agriculture as they protect soil fertility, watershed, and local biodiversity. They also play an important role in maintaining ecosystem stability. This work was carried out to study the diversity and regeneration status of some oak forests in Garhwal Himalaya, India. A total of 18 tree species belonging to 16 genera and 12 families were reported from the study area. Species richness varied for trees (4–7, saplings (3–10, and seedlings (2–6. Seedling and sapling densities (Ind/ha varied between 1,376 Ind/ha and 9,600 Ind/ha and 167 Ind/ha and 1,296 Ind/ha, respectively. Species diversity varied from 1.27 to 1.86 (trees, from 0.93 to 3.18 (saplings, and from 0.68 to 2.26 (seedlings. Total basal area (m2/ha of trees and saplings was 2.2–87.07 m2/ha and 0.20–2.24 m2/ha, respectively, whereas that of seedlings varied from 299 cm2/ha to 8,177 cm2/ha. Maximum tree species (20–80% had “good” regeneration. Quercus floribunda, the dominant tree species in the study area, showed “poor” regeneration, which is a matter of concern, and therefore, proper management and conservation strategies need to be developed for maintenance and sustainability of this oak species along with other tree species that show poor or no regeneration.

  9. Ectomycorrhiza communities of red oak (Quercus rubra L.) of different age in the Lusatian lignite mining district, East Germany.

    Science.gov (United States)

    Gebhardt, S; Neubert, K; Wöllecke, J; Münzenberger, B; Hüttl, R F

    2007-06-01

    Ectomycorrhizal (ECM) communities were assessed on a 720 m(2) plot along a chronosequence of red oak (Quercus rubra) stands on a forest reclamation site with disturbed soil in the lignite mining area of Lower Lusatia (Brandenburg, Germany). Adjacent to the mining area, a red oak reference stand with undisturbed soil was investigated reflecting mycorrhiza diversity of the intact landscape. Aboveground, sporocarp surveys were carried out during the fruiting season in a 2-week interval in the years 2002 and 2003. Belowground, ECM morphotypes were identified by comparing sequences of the internal transcribed spacer regions from nuclear rDNA with sequences from the GenBank database. Fifteen ECM fungal species were identified as sporocarps and 61 belowground as determined by morphological/anatomical and molecular analysis of their ectomycorrhizas. The number of ECM morphotypes increased with stand age along the chronosequence. However, the number of morphotypes was lower in stands with disturbed soil than with undisturbed soil. All stands showed site-specific ECM communities with low similarity between the chronosequence stands. The dominant ECM species in nearly all stands was Cenococcum geophilum, which reached an abundance approaching 80% in the 21-year-old chronosequence stand. Colonization rate of red oak was high (>95%) at all stands besides the youngest chronosequence stand where colonization rate was only 15%. This supports our idea that artificial inoculation with site-adapted mycorrhizal fungi would enhance colonization rate of red oak and thus plant growth and survival in the first years after outplanting.

  10. Natural hybridisation between kermes (Quercus coccifera L.) and holm oaks (Q. ilex L.) revealed by microsatellite markers.

    Science.gov (United States)

    Ortego, Joaquín; Bonal, Raúl

    2010-01-01

    Hybridisation between species of the genus Quercus is a common phenomenon as a result of weak reproductive isolation mechanisms between phylogenetically close species that frequently co-occur in mixed stands. In this study, we use microsatellite markers to analyse introgression between kermes (Quercus coccifera L.) and holm (Q. ilex L.) oak, two closely related taxa that frequently dominate the landscape in extensive areas in the Mediterranean region. All tested microsatellites amplified and were polymorphic in both kermes and holm oaks. Bayesian admixture analyses showed a good correspondence between each species and one of the two inferred genetic clusters. Five sampled individuals were a priori tentatively identified as hybrids on the basis of intermediate morphological characteristics, and it was confirmed that they also presented mixed genotypes. However, we also detected different levels of genetic introgression among morphologically pure individuals, suggesting that successful backcrossing and/or reduced phenotypic expression of genetic variance in certain individuals may have resulted in strong convergence towards a single species phenotype.

  11. Drought response of upland oak (Quercus L.) species in Appalachian hardwood forests of the southeastern USA

    Science.gov (United States)

    Tara L. Keyser; Peter M. Brown

    2016-01-01

    Key message In Appalachian hardwood forests, density, stem size, and productivity affected growth duringdrought for red oak, but not white oak species. Minor effects of density suggest that a single low thinning does...

  12. Genetic structure of a natural oak community in central Italy: Evidence of gene flow between three sympatric white oak species (Quercus, Fagaceae

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    Gaby Antonecchia

    2015-12-01

    Full Text Available Incomplete reproductive barriers between species, especially in sympatric areas where several species coexist, may result in hybridization and an increase in genetic diversity. Here we assessed the amount of genetic diversity in a community of three interfertile and sympatric European oaks (Quercus frainetto Ten., Q. petraea Liebl. Matt. and Q. pubescens Willd. situated in central Italy. We used 11 microsatellite markers derived from Expressed Sequence Tag (EST-SSRs and we implemented a Bayesian clustering analysis to assign individuals to species or hybrids. All genotyped loci were polymorphic for all the species and three genetic clusters corresponding to each species were detected. Significant differences and a higher level of gene flow were observed between the three oak species. Occurrence of hybrids varied markedly within the studied area: hybrids between Q. petraea and Q, pubescens were the most frequent, while hybrids between Q. petraea and Q. frainetto were particularly rare. Q. pubescens and Q. petraea showed the highest number of alleles compared to Q. frainetto,which was characterized by a low number of private, but highly frequent, alleles. However, Q. frainetto showed a lower genetic diversity and a stronger reproductive isolation from the other two oak species.

  13. Does Habitat Matter in an Urbanized Landscape? The Birds of the Garry Oak (Quercus garryana) Ecosystem of Southeastern Vancouver Island, British Columbia

    Science.gov (United States)

    Richard E. Feldman; Pam G. Krannitz

    2005-01-01

    The Garry oak (Quercus garryana) ecosystem was once a dominant habitat type on southeastern Vancouver Island, British Columbia, but urbanization has lead to massive habitat loss and fragmentation (Hebda 1993). Most bird species are expected to respond negatively to urbanization because of increased patch isolation, increased predation pressure, and negative edge...

  14. Post-planting treatments increase growth of Oregon white oak (Quercus garryana Dougl. ex Hook.) seedlings.

    Science.gov (United States)

    W.D. Devine; C.A. Harrington; L.P. Leonard

    2007-01-01

    The extent of Oregon white oak woodland and savanna ecosystems in the Pacific Northwest has diminished significantly during the past century, and planting of Oregon white oak seedlings is often necessary for restoring these plant communities. Our objective was to evaluate the effects of tree shelters, control of competing vegetation, fertilization, irrigation, and...

  15. Stem-quality of sessile oak (Quercus petraea (Matt. Liebl. trees, Tuscany, Italy

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    Grifoni F

    2007-01-01

    Full Text Available The Regional Forest Inventory reports a significant presence of sessile oak in Tuscany. The noticeable increase of sessile oak timber value in better-shaped stems, suggests the advance evaluation of the quality of standing trees. In this way, the consistency of the applied silvicultural rules may be verified, too. The research trial was undertaken in a stand aged 41 to 45 originated from reafforestation a few hectares wide, located at Monte Lignano (Arezzo. The stand structure is not homogeneous as for tree size and tree species composition. Qualitative field surveys were carried out into three well-discernible stand types within the reforested area: a scattered sessile oak trees into a withered chestnut orchard; b pure sessile oak stands; c scattered sessile oak trees into a poor chestnut coppice. Data collected at about one half of the foreseen stand life span showed the different stem quality into each structure and type. In addition, a diffuse growth of epicormic branches along sessile oak stems was observed into pure stands (b, following main crop thinnings and subordinate layer exploitation. This practice consisted therefore in a worsening of oak stems quality. As already showed by the practice of silviculture into sessile oak stands across Europe, these results proved that the production of valuable stems needs suited and well-timed tending practices.

  16. An analysis of phenotypic selection in natural stands of northern red oak (Quercus rubra L.)

    Science.gov (United States)

    Jeffery W. Stringer; David B. Wagner; Scott E. Schlarbaum; Daniel B. Houston

    1995-01-01

    Comparison of growth and stem quality parameters of 19-year-old progeny from superior and comparison trees indicates that rigorous phenotypic selection of trees in natural stands may not be an efficient method of parent tree selection for Quercus rubra L. Total tree height, dbh, number of branches in the butt log, fork height, and number of mainstem...

  17. Branch bark of holm oak (Quercus ilex L.) for reconstructing the temporal variations of atmospheric deposition of hexavalent chromium.

    Science.gov (United States)

    Drava, Giuliana; Anselmo, Marco; Brignole, Daniele; Giordani, Paolo; Minganti, Vincenzo

    2017-03-01

    The bark from the annual segments of the branches of holm oak (Quercus ilex L.) is exposed to trace element deposition for a known period of time and thus it is a possible candidate as a bioindicator for reconstructing historical changes in pollution. A series of samples were analysed for Cr(VI) concentration by electrothermal atomic absorption spectrometry (ET-AAS) after selective extraction in a sodium carbonate solution. In this way the atmospheric deposition of Cr(VI) was reconstructed from 2001 to 2010 in an area where an industrial plant produced Cr(VI) compounds until 2003. The present study shows the potential of this type of sample as a natural archive for persistent pollutants, useful for monitoring changes that occur before a monitoring programme is established, with the advantage of being easy to collect almost everywhere. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Conservation and fruit biology of Sichou oak (Quercus sichourensis, Fagaceae – A critically endangered species in China

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    Ke Xia

    2016-10-01

    Full Text Available Several conservation programs have been started for the critically endangered Sichou oak (Quercus sichourensis since 2007. These programs include detailed field investigations, seedling cultivation and research on the fruit biology of the species. In this study, we first report on the five mature individual trees found in our 9-year field investigation. Thus far, a total of 10 mature individuals have been recorded. All Q. sichourensis trees are healthy and most produce healthy acorns. Acorns of Q. sichourensis are large with dry masses of 8.0–14.0 g. These acorns had high moisture contents at collection and died shortly after (7–28 d when dried with silica gel. Characteristics of Q. sichourensis acorns varied between populations. Compared with the acorns from Funing, the acorns collected from Ceheng were bigger, more viable (germination percentage was up to 96%, less sensitive to desiccation, and germinated faster. Q. sichourensis occurs in regions with a distinct 5–6 month dry season. Habitat degradation is largely responsible for the rareness of Quercus sichorensis, but desiccation sensitivity of the acorns may also limit the regeneration of the species and potentially lead to its continued rareness. As a species with extremely small populations (PSESP, Q. sichourensis is facing high risk of extinction and should be defined as a Critically Endangered species in the global IUCN Red List.

  19. Evaluation of antioxidant interactions in combined extracts of green tea (Camellia sinensis), rosemary (Rosmarinus officinalis) and oak fruit (Quercus branti).

    Science.gov (United States)

    Ranjbar Nedamani, Elham; Sadeghi Mahoonak, Alireza; Ghorbani, Mohammad; Kashaninejad, Mehdi

    2015-07-01

    Green tea (Camellia sinensis), rosemary (Rosmarinus officinalis) and oak fruit (Quercus branti) are of known medicinal plants used in traditional medicine. They provide substantial antioxidant activities but the possible antioxidant interaction between them has not been studied. In the present study first the bioactive compounds from these three plants were first extracted and thereafter assayed for total phenols, 2, 2-diphenyl-1- picrylhydrazyl (DPPH) radical scavenging activity, total antioxidant capacity (TAOC) and reducing power. In addition, the antioxidant properties of the extracts individually and in combinations were evaluated in soy bean oil as food system. There was a direct relation between total phenolics and antioxidant activities of extracts. Green tea and oak fruit extracts had the highest and least activity, respectively. All three kinds of interactions (synergistic, antagonistic and additive) were observed. In soy bean oil, the only effect was antagonism but even with this effect, combined extract was significantly (P < 0.05) better than butylated hydroxytoluene (BHT) and control sample. Results showed that these three natural extracts and their combination can be effectively used as a substituent of synthetic antioxidant BHT.

  20. Association between radionuclides (210Po and 210Pb) and antioxidant enzymes in oak (Quercus coccifera) and mastic tree (Pistacia lentiscus).

    Science.gov (United States)

    Uğur Görgün, A; Aslan, E; Kül, M; İlhan, S; Dimlioğlu, G; Bor, M; Özdemir, F

    2017-08-01

    The activity levels of naturally occurring radionuclides Polonium-210 and lead-210 in different subjects including plant species have direct or indirect impact on human beings. High levels of ionising radiation cause oxidative stress and the interaction between antioxidative defense and radionuclides is not well established in plant systems. In this study, we aimed to understand the impact of oxidative stress caused by 210Po and 210Pb in two Mediterranean plants; Quercus coccifera and Pistacia lentiscus. We analysed the constitutive and seasonal levels of 210Po, 210Pb, lipid peroxidation levels, superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities in the field-collected samples. The highest activity concentrations of 210Po and 210Pb were detected in both plants in summer and Q. coccifera had higher levels than that of P. lentiscus. SOD and APX activity trends were different between oak and mastic; as compared to P. lentiscus, Q. coccifera efficiently used the two major components of antioxidative defense. Lipid peroxidation levels were low in both plants in all seasons except that of spring which were in good agreement with high antioxidant enzyme activities. In conclusion, we found that high 210Po and 210Pb activity concentrations in oak and mastic did not interfere with their growth and life cycles. The ability of both plants for survival and adaptation to Mediterranean environmental constraints provided an additional advantage for coping radionuclide induced oxidative stress as well. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Specific polyphenols and tannins are associated with defense against insect herbivores in the tropical oak Quercus oleoides.

    Science.gov (United States)

    Moctezuma, Coral; Hammerbacher, Almuth; Heil, Martin; Gershenzon, Jonathan; Méndez-Alonzo, Rodrigo; Oyama, Ken

    2014-05-01

    The role of plant polyphenols as defenses against insect herbivores is controversial. We combined correlative field studies across three geographic regions (Northern Mexico, Southern Mexico, and Costa Rica) with induction experiments under controlled conditions to search for candidate compounds that might play a defensive role in the foliage of the tropical oak, Quercus oleoides. We quantified leaf damage caused by four herbivore guilds (chewers, skeletonizers, leaf miners, and gall forming insects) and analyzed the content of 18 polyphenols (including hydrolyzable tannins, flavan-3-ols, and flavonol glycosides) in the same set of leaves using high performance liquid chromatography and mass spectrometry. Foliar damage ranged from two to eight percent per region, and nearly 90% of all the damage was caused by chewing herbivores. Damage due to chewing herbivores was positively correlated with acutissimin B, catechin, and catechin dimer, and damage by mining herbivores was positively correlated with mongolinin A. By contrast, gall presence was negatively correlated with vescalagin and acutissimin B. By using redundancy analysis, we searched for the combinations of polyphenols that were associated to natural herbivory: the combination of mongolinin A and acutissimin B had the highest association to herbivory. In a common garden experiment with oak saplings, artificial damage increased the content of acutissimin B, mongolinin A, and vescalagin, whereas the content of catechin decreased. Specific polyphenols, either individually or in combination, rather than total polyphenols, were associated with standing leaf damage in this tropical oak. Future studies aimed at understanding the ecological role of polyphenols can use similar correlative studies to identify candidate compounds that could be used individually and in biologically meaningful combinations in tests with herbivores and pathogens.

  2. Volatile compounds and sensorial characterization of wines from four Spanish denominations of origin, aged in Spanish Rebollo (Quercus pyrenaica Willd.) oak wood barrels.

    Science.gov (United States)

    Fernández de Simón, Brígida; Cadahía, Estrella; Sanz, Miriam; Poveda, Pilar; Perez-Magariño, Silvia; Ortega-Heras, Miriam; González-Huerta, Carlos

    2008-10-08

    The evolution of almost 40 oak-related volatile compounds and the sensorial characteristics of red wines from four Spanish denominations of origin (DOs) (Bierzo, Toro, Ribera de Duero, and Rioja) during aging in barrels made of Rebollo oak wood, Quercus pyrenaica, were studied and compared to the same wines aged in American and French oak barrels. Each oak wood added unique and special characteristics to the wine, and in addition, each wine showed a different ability to extract the compounds, which result in these characteristics from the oak wood. In general, wines aged in Q. pyrenaica wood were characterized by high levels of eugenol, guaiacol, and other volatile phenols. In regards to compounds like cis-whiskylactone or maltol, the behavior of this wood is very similar to that of American oaks. When considering phenolic aldehydes and ketones, the levels of these compounds are intermediate between those of French and American woods and depend greatly on the type of wine. The type of oak, on the other hand, does not affect the chromatic characteristics of the wines. In sensory analysis, the biggest differences are found in the olfactory phase. Among the four DOs studied, wine aged in Q. pyrenaica presented the highest notes of wood, with more aromas of roasting, toasting, milky coffee, spices, or wine-wood interactions. The wines aged in barrels made of Q. pyrenaica wood were highly regarded, and preference was shown for them over those same wines when they had been aged in barrels of American or French oak.

  3. OakContigDF159.1, a reference library for studying differential gene expression in Quercus robur during controlled biotic interactions: use for quantitative transcriptomic profiling of oak roots in ectomycorrhizal symbiosis.

    Science.gov (United States)

    Tarkka, Mika T; Herrmann, Sylvie; Wubet, Tesfaye; Feldhahn, Lasse; Recht, Sabine; Kurth, Florence; Mailänder, Sarah; Bönn, Markus; Neef, Maren; Angay, Oguzhan; Bacht, Michael; Graf, Marcel; Maboreke, Hazel; Fleischmann, Frank; Grams, Thorsten E E; Ruess, Liliane; Schädler, Martin; Brandl, Roland; Scheu, Stefan; Schrey, Silvia D; Grosse, Ivo; Buscot, François

    2013-07-01

    Oaks (Quercus spp.), which are major forest trees in the northern hemisphere, host many biotic interactions, but molecular investigation of these interactions is limited by fragmentary genome data. To date, only 75 oak expressed sequence tags (ESTs) have been characterized in ectomycorrhizal (EM) symbioses. We synthesized seven beneficial and detrimental biotic interactions between microorganisms and animals and a clone (DF159) of Quercus robur. Sixteen 454 and eight Illumina cDNA libraries from leaves and roots were prepared and merged to establish a reference for RNA-Seq transcriptomic analysis of oak EMs with Piloderma croceum. Using the Mimicking Intelligent Read Assembly (MIRA) and Trinity assembler, the OakContigDF159.1 hybrid assembly, containing 65 712 contigs with a mean length of 1003 bp, was constructed, giving broad coverage of metabolic pathways. This allowed us to identify 3018 oak contigs that were differentially expressed in EMs, with genes encoding proline-rich cell wall proteins and ethylene signalling-related transcription factors showing up-regulation while auxin and defence-related genes were down-regulated. In addition to the first report of remorin expression in EMs, the extensive coverage provided by the study permitted detection of differential regulation within large gene families (nitrogen, phosphorus and sugar transporters, aquaporins). This might indicate specific mechanisms of genome regulation in oak EMs compared with other trees. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  4. Phenology, dichogamy, and floral synchronization in a northern red oak (Quercus Rubra L.) seed orchard

    Science.gov (United States)

    We developed a novel scoring system to assess spring phenology in a northern red oak clonal seed orchard. The system was used to score between 304 and 364 ramets for three reproductive seasons and place clones into early, middle, and late phenology groups. While the absolute number of clones in ea...

  5. Comparing cold-stored and freshly lifted water oak (Quercus nigra) seedlings based on physiological parameters

    Science.gov (United States)

    Rosa C. Goodman; Kent G. Apostol; Douglass F. Jacobs; Barrett C. Wilson; Emile S. Gardiner

    2007-01-01

    Water oak is often used in afforestation projects in the Lower Mississippi Alluvial Valley, but its field performance is often poor due to low survival rates and severe top dieback immediately after planting. The poor physiological quality of planting stock may be a contributing factor to this transplanting problem. In this study, cold storage was investigated to...

  6. Mating patterns in a savanna population of valley oak (Quercus labata Neé)

    Science.gov (United States)

    Victoria L. Sork; Frank W. Davis; Rodney J. Dyer; Peter E. Smouse

    2002-01-01

    California valley oak is threatened by landscape alteration and failing recruitment in remnant stands. Its reproductive ecology is a key element of the seedling recruitment process. We first examine the mating system, to determine the extent of inbreeding in a population at Sedgwick Reserve, in Santa Barbara County. We then quantify variation in germination success and...

  7. Physiological and proteomics analyses of Holm oak (Quercus ilex subsp. ballota [Desf.] Samp.) responses to Phytophthora cinnamomi.

    Science.gov (United States)

    Sghaier-Hammami, Besma; Valero-Galvàn, José; Romero-Rodríguez, M Cristina; Navarro-Cerrillo, Rafael Ma; Abdelly, Chedly; Jorrín-Novo, Jesús

    2013-10-01

    Phytophthora cinnamomi is one of the agents that trigger the decline syndrome in Quercus spp., this being a serious threat to Mediterranean Holm oak forest sustainability and reforestation programs. Quercus ilex responses to Phytophthora cinnamomi have been studied in one-year olds seedlings from two Andalucía provenances, assessing the physiological water status and photosynthesis-related parameters. Upon inoculation with mycelium a reduction in water content, chlorophyll fluorescence, stomatal conductance and gas exchange was observed along a 90 days post inoculation period in both provenances. The reduction was higher in the most susceptible (SSA) provenance, than in the most tolerant (PCO), being these typical plant responses to drought stress. Leaf protein profiles were analyzed in non-inoculated and inoculated seedlings from the two provenances by using a 2-DE coupled to MS proteomics strategy. Ninety seven proteins changing in abundance in response to the inoculation were successfully identified after MALDI-TOF-TOF analyses. The largest group of variable identified proteins were chloroplasts ones, and they were involved in the photosynthesis, Calvin cycle and carbohydrate metabolism. It was noted that a general tendency was a decrease in the protein abundance as a consequence of the inoculation, being it less accused in the least susceptible, the Northern provenance (PCO), than in the most susceptible, the Southern provenance (SSA). This trend is clearly manifested in photosynthesis, amino acid metabolism and stress/defence proteins. On the contrary, some proteins related to starch biosynthesis, glycolysis and stress related peroxiredoxin showed an increase upon inoculation. These changes in protein abundance were correlated to the estimated physiological parameters and have been frequently observed in plants subjected to drought stress. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. Some characters of the pollen of spring and summer flowering common oak (Quercus robur L.

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    Batos Branislava

    2012-01-01

    Full Text Available Summer flowering of the common oak is a natural rarity, considering the large area of the species natural distribution. This phenomenon can be classified as an ancestral (atavistic property. Pollen morphological and physiological characters from spring flowering male inflorescences collected over the period 2004 - 2007 and summer flowering male inflorescences collected in 1999 were compared. The analysis included the pollen of a tree with frequent summer flowering and a control tree with spring flowering only. The size and form of summer pollen differed from the spring flowering pollen. The germination percentage and germination energy depended on the pollen growing medium (0, 5, 10, 15, 20, 25% sucrose solution, year of collection (2004 - 2007, temperature (+5°C and -20°C and storage period (1 to 24 months. The study results are significant for the explanation of common oak phylogenetic development, and they contribute to the knowledge of pollen characters under the effects of different factors.

  9. The bark of holm oak (Quercus ilex, L.) for airborne Cr(VI) monitoring.

    Science.gov (United States)

    Minganti, Vincenzo; Drava, Giuliana; De Pellegrini, Rodolfo; Anselmo, Marco; Modenesi, Paolo; Malaspina, Paola; Giordani, Paolo

    2015-01-01

    In this work, the bark of holm oak was used as a bioindicator to study the atmospheric distribution of Cr(VI). The chosen method (alkaline extraction and atomic absorption determination) was found in the literature, adapted for use with the matrix involved, and validated. The method had some limits, but provided an excellent estimation of Cr(VI) concentrations with good sensitivity and a reasonable time of analysis and cost. Thirty-four samples of holm oak collected in three areas characterised by different possible sources of pollution (the area near a former chromate production plant, an urban area, and a rural "reference" area) were analysed, obtaining concentrations ranging from 1.54 to 502 μg g(-1) near the industrial plant, ranging from 0.22 to 1.35 μg g(-1) in the urban area, and mostly below the detection limit (0.04 μg g(-1)) in the rural area. The bark of holm oak proved to be a good bioindicator to detect Cr(VI) in the environment. The extraction procedure followed by atomic absorption analysis is simple, provides good sensitivity, and it is suitable for environmental studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Proteomic analysis of Holm oak (Quercus ilex subsp. ballota [Desf.] Samp.) pollen.

    Science.gov (United States)

    Valero Galván, José; Valledor, Luis; González Fernandez, Raquel; Navarro Cerrillo, Rafael M; Jorrín-Novo, Jesus V

    2012-05-17

    This paper presents an analysis of Holm oak pollen proteome, together with an evaluation of the potentiality that a proteomic approach may have in the provenance variability assessment. Proteins were extracted from pollen of four Holm oak provenances, and they were analyzed by gel-based (1- and 2-DE in combination with MALDI-TOF/TOF) and gel-free (nLC-LTQ Orbitrap MS) approaches. A comparison of 1- and 2-DE protein profiles of the four provenances revealed significant differences, both qualitative and quantitative, in abundance (18 bands and 16 spots, respectively). Multivariate statistical analysis carried out on bands and spots clearly showed distinct associations between provenances, which highlight their geographical origins. A total of 100 spots selected from the 402 spots observed on 2-DE gels were identified by MALDI-TOF/TOF. Moreover, a complementary gel-free shotgun approach was performed by nLC-LTQ Orbitrap MS. The identified proteins were classified according to biological processes, and most proteins in both approaches were related to metabolism and defense/stress processes. The nLC-LTQ Orbitrap MS analysis allowed us the identification of proteins belonging to the cell wall and division, transport and translation categories. Besides providing the first reference map of Holm oak pollen, our results confirm previous studies based on morphological observations and acorn proteomic analysis. Moreover, our data support the valuable use of proteomic techniques as phylogenetic tool in plant studies. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. A method to quantify infection and colonization of holm oak (Quercus ilex) roots by Phytophthora cinnamomi.

    Science.gov (United States)

    Ruiz-Gómez, Francisco J; Sánchez-Cuesta, Rafael; Navarro-Cerrillo, Rafael M; Pérez-de-Luque, Alejandro

    2012-09-13

    Phytophthora cinnamomi Rands. is an important root rot pathogen widely distributed in the north hemisphere, with a large host range. Among others diseases, it is known to be a principal factor in the decline of holm oak and cork oak, the most important tree species in the "dehesa" ecosystem of south-western Spain. Previously, the focus of studies on P. cinnamomi and holm oak have been on molecular tools for identification, functional responses of the host, together with other physiological and morphological host variables. However, a microscopic index to describe the degree of infection and colonization in the plant tissues has not yet been developed. A colonization or infection index would be a useful tool for studies that examine differences between individuals subjected to different treatments or to individuals belonging to different breeding accessions, together with their specific responses to the pathogen. This work presents a methodology based on the capture and digital treatment of microscopic images, using simple and accessible software, together with a range of variables that quantify the infection and colonization process.

  12. A method to quantify infection and colonization of holm oak (Quercus ilex roots by Phytophthora cinnamomi

    Directory of Open Access Journals (Sweden)

    Ruiz-Gómez Francisco J

    2012-09-01

    Full Text Available Abstract Phytophthora cinnamomi Rands. is an important root rot pathogen widely distributed in the north hemisphere, with a large host range. Among others diseases, it is known to be a principal factor in the decline of holm oak and cork oak, the most important tree species in the “dehesa” ecosystem of south-western Spain. Previously, the focus of studies on P. cinnamomi and holm oak have been on molecular tools for identification, functional responses of the host, together with other physiological and morphological host variables. However, a microscopic index to describe the degree of infection and colonization in the plant tissues has not yet been developed. A colonization or infection index would be a useful tool for studies that examine differences between individuals subjected to different treatments or to individuals belonging to different breeding accessions, together with their specific responses to the pathogen. This work presents a methodology based on the capture and digital treatment of microscopic images, using simple and accessible software, together with a range of variables that quantify the infection and colonization process.

  13. Drought reduced monoterpene emissions from the evergreen Mediterranean oak Quercus ilex: results from a throughfall displacement experiment

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    S. Rambal

    2009-07-01

    Full Text Available The effects of water limitations on the emission of biogenic volatile organic compounds are not well understood. Experimental approaches studying drought effects in natural conditions are still missing. To address this question, a throughfall displacement experiment was set up in a natural forest of Quercus ilex, an evergreen Mediterranean oak emitting monoterpenes. Mature trees were exposed in 2005 and 2006 either to an additional drought, to irrigation or to natural drought (untreated control. In both years, absolute monoterpene emission rates as well as the respective standard factors of the trees exposed to normal and additional drought strongly declined during the drought periods. Monoterpene emissions were lower in year 2006 than in year 2005 (factor 2 due to a more pronounced summer drought period in this respective year. We observed a significant difference between the irrigation and additional drought or control treatment: irrigated trees emitted 82% more monoterpenes during the drought period 2006 than the trees of the other treatments. However, no significant effect on monoterpene emission was observed between normal and additional drought treatments, despite a significant effect on leaf water potential and photochemical efficiency. During the development of drought, monoterpene emissions responded exponentially rather than linearly to decreasing leaf water potential. Emissions rapidly declined when the water potential dropped below −2 MPa and photosynthesis was persistently inhibited. Monoterpene synthase activities measured in vitro showed no clear reduction during the same period. From our results we conclude that drought significantly reduces monoterpene fluxes of Mediterranean Holm oak forest into the atmosphere due to a lack of primary substrates coming from photosynthetic processes.

  14. Remobilization of acorn nitrogen for seedling growth in holm oak (Quercus ilex), cultivated with contrasting nutrient availability.

    Science.gov (United States)

    Villar-Salvador, Pedro; Heredia, Norberto; Millard, Peter

    2010-02-01

    The relative contribution of nitrogen (N) reserves from seeds or uptake by the roots to the growth and N content of young seedlings has received little attention. In this study, we investigated the contribution of N from the acorn or uptake by the roots to the N content of holm oak (Quercus ilex L.) seedlings and determined if remobilization of acorn N was affected by nutrient availability in the growing media. Q. ilex seedlings were cultivated for 3 months, until the end of the second shoot flush of growth, with three N fertilization rates: 8.6 mM N, 1.4 mM N or no fertilization. Fertilizer N was enriched in (15)N. Between 62 and 75% of the N contained in high and low fertilized seedlings, respectively, at the end of the second flush of growth was derived from the acorn. However, the dependence on acorn N was greater during the early root growth and first shoot flush of growth and decreased during the second shoot flush of growth, with root uptake contributing 32-54% of plant new N in this latter developmental stage in high and low fertilized plants, respectively. Fertilization rate did not affect the amount of N taken up during the earliest developmental stages, but it increased it during the second shoot flush of growth. Fertilization increased the mass of the shoot segment formed during the second shoot flush of growth and reduced the root mass, with no effect on whole plant growth. Remobilization of acorn N was faster in unfertilized plants than in fertilized plants. It is concluded that the holm oak seedlings depend greatly upon acorn N until the end of the second shoot flush of growth, that significant root N uptake starts at the beginning of the second shoot flush of growth and that acorn N remobilization is a plastic process that is accelerated under extremely low substratum nutrient content.

  15. Seed production timing influences seedling fitness in the tropical live oak Quercus oleoides of Costa Rican dry forests.

    Science.gov (United States)

    Center, Alyson; Etterson, Julie R; Deacon, Nicholas John; Cavender-Bares, Jeannine

    2016-08-01

    Reproductive phenology is important for tree species that occur in seasonally dry environments, particularly for those with desiccation-sensitive, nondormant seeds. In this study, we compared germination, growth, and survival of seeds of the evergreen tropical live oak Quercus oleoides produced at different times during the wet season at two sites that differ in rainfall along an elevation gradient. Our goal was to determine the effects of reproductive timing on germination and juvenile fitness for this widespread species in seasonally dry forests of northwestern Costa Rica. We collected seeds early and late in a single wet season from two populations with contrasting rainfall and reciprocally planted them into common gardens. Two watering treatments (ambient and supplemental watering) were established at the drier low-elevation garden. Seeds were exposed to ambient rainfall at the wetter high-elevation garden. We conducted selection analyses using aster models to examine variation in selection on seed size and timing of germination. Trees of Q. oleoides had higher fitness when seeds were produced, dispersed and germinated late in the wet season. Postgermination, water limitation during the dry season reduced seedling fitness by decreasing survival but not growth. In contrast to studies in temperate climates where earlier germination is typically favored, we show that selection on days to germination is temporally and spatially heterogeneous. Selection was found to favor either rapid or delayed germination depending on seed cohort and habitat. © 2016 Botanical Society of America.

  16. Antioxidant, anti-inflammatory and anticarcinogenic activities of edible red oak (Quercus spp.) infusions in rat colon carcinogenesis induced by 1,2-dimethylhydrazine.

    Science.gov (United States)

    Moreno-Jimenez, Martha Rocío; Trujillo-Esquivel, Fátima; Gallegos-Corona, Marco A; Reynoso-Camacho, Rosalia; González-Laredo, Rubén Francisco; Gallegos-Infante, José Alberto; Rocha-Guzmán, Nuria Elizabeth; Ramos-Gomez, Minerva

    2015-06-01

    Red oak (Quercus spp.) leaves are traditionally used as food in Mexico, and some of their infusions have potential anticarcinogenic and anti-inflammatory effects; however, these properties have not yet been scientifically tested. The aim of this work was to explore the anti-inflammatory activity in HT-29 cells and anticarcinogenic effect in 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis of red oak infusions. Quercus infusions were prepared and administered as the sole source of drink to male Sprague-Dawley rats (1% w/v) for the entire 26-week experimental period. On week 4, rats received 8 subcutaneous injections of DMH (21 mg/kg body weight) once a week. The results showed that mean tumor (0.9 ± 0.2 vs. 2.6 ± 0.3) and multiplicity (1.2 ± 0.1 vs. 2.0 ± 0.23), and β-catenin protein level (2.2-fold) in adenocarcinomas were significantly lower in Quercus  sideroxyla-treated group compared with DMH group. By contrast, Quercus  durifolia and Quercus  eduardii infusions had no protective effect. Additionally, the experiments in HT-29 cells confirmed that Q. sideroxyla infusion effectively decreased the levels of the inflammatory markers COX-2 and IL-8 by modulating the expression of NF-κB. These results highlight some of the molecular mechanisms related to the chemopreventive effect of Q. sideroxyla infusion and its potential value as a source of bioactive compounds. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Provenance-specific growth responses to drought and air warming in three European oak species (Quercus robur, Q. petraea and Q. pubescens).

    Science.gov (United States)

    Arend, Matthias; Kuster, Thomas; Günthardt-Goerg, Madeleine S; Dobbertin, Matthias

    2011-03-01

    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.

  18. Decline in holm oak coppices (Quercus ilex L. subsp. ballota (Desf.) Samp.): biometric and physiological interpretations

    Energy Technology Data Exchange (ETDEWEB)

    Serrada, R.; Gómez-Sanz, V.; Aroca, M.J.; Otero, J.; Bravo-Fernández, J.A.; Roig, S.

    2017-11-01

    Aim of the study: To analyse the decline in aged holm oak coppice forests as regards above-ground and below-ground fractions and physiological features. Area of study: Centre of the Iberian Peninsula (Guadalajara province). Material and methods: 26 pairs of holm oak stools with different vigour but with similar site and structural characteristics within each pair were selected. Morphological (basal area, number of stools, maximum height) and physiological traits (leaf water potential, stomatal conductance) of the standing stools were assessed. Their aerial and underground parts were extracted and different size fractions of both their above and below-ground biomass were quantified. Linear mixed models were built to test the effect of ’Stool vigour’ on the mean behaviour of the measured variables. Additionally, for the aerial part, linear regressions between the weights of the different size fractions and the basal area at breast height were performed using ‘Stool vigour’ as a fixed factor. Main results: For the same site, root depth, and number and diameter of shoots than good vigour stools, poor vigour stools displayed: lower predawn water potential, greater leaf mass per unit of area; lower total leaf area; lower above-ground biomass (in total as well as per fractions); lower fine roots biomass; lower proportion of leaf biomass and a greater proportion of biomass of both all roots and those with diameter 2-7 cm. Research highlights: The above-ground physiological and morphological characteristics of declined stools are interpreted as poorer adaptation to site conditions. Root system architecture was found to be relevant to explain this behaviour.

  19. Polyphenols in red wine aged in acacia (Robinia pseudoacacia) and oak (Quercus petraea) wood barrels.

    Science.gov (United States)

    Sanz, Miriam; Fernández de Simón, Brígida; Esteruelas, Enrique; Muñoz, Angel Ma; Cadahía, Estrella; Hernández, Ma Teresa; Estrella, Isabel; Martinez, Juana

    2012-06-30

    Polyphenolic composition of two Syrah wines aged during 6 or 12 months in medium toasting acacia and oak 225L barrels was studied by LC-DAD-ESI/MS. A total of 43 nonanthocyanic phenolic compounds were found in all wines, and other 15 compounds only in the wines from acacia barrels. Thus, the nonanthocyanic phenolic profile could be a useful tool to identify the wines aged in acacia barrels. Among all of them the dihydrorobinetin highlights because of its high levels, but also robinetin, 2,4-dihydroxybenzaldehyde, a tetrahydroxydihydroflavonol, fustin, butin, a trihydroxymethoxydihydroflavonol and 2,4-dihydroxybenzoic acid were detected at appreciable levels in wines during aging in acacia barrels, and could be used as phenolic markers for authenticity purposes. Although longer contact time with acacia wood mean higher concentrations of phenolic markers found in wines, the identification of these wines will also be easy after short aging times due the high levels reached by these compounds, even after only 2 months of aging. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Stomatal patchiness in the Mediterranean holm oak (Quercus ilex L.) under water stress in the nursery and in the forest.

    Science.gov (United States)

    Guàrdia, Mercè; Fernàndez, Jordi; Elena, Georgina; Fleck, Isabel

    2012-07-01

    The evergreen holm oak Quercus ilex L. is the most representative tree in Mediterranean forests. Accurate estimation of the limiting factors of photosynthesis for Q. ilex and the prediction of ecosystem water-use efficiency by mechanistic models can be achieved only by establishing whether this species shows heterogenic stomatal aperture, and, if so, the circumstances in which this occurs. Here, we collected gas-exchange and chlorophyll fluorescence data in Q. ilex leaves from a nursery to measure the effects of stomatal oscillations on PSII quantum yield (Φ(PSII)) under water stress. Stomatal conductance (g(s)) was used as an integrative indicator of the degree of water stress. Images of chlorophyll fluorescence showed heterogeneous Φ(PSII) when g(s) was 2.5%. A parallel study in the forest confirmed heterogeneous Φ(PSII) values in leaves in response to declining water availability. Three kinds of Q. ilex individuals were distinguished: those resprouting after a clear-cut (resprouts, R); intact individuals growing in the same clear-cut area as resprouts (controls, C); and intact individuals in a nearby, undisturbed area (forest controls, CF). Patchiness increased in C and CF in response to increasing drought from early May to late July, whereas in R, Φ(PSII) values were maintained as a result of their improved water relations since the pre-existing roots were associated with a smaller aerial biomass. Patchiness was related to a % CV of Φ(PSII) values >4 and associated in the summer with mean g(s) values of 30 mmol H(2)O m(-2) s(-1). Under milder drought in spring, Φ(PSII) patchiness was less strictly related to g(s) variations, pointing to biochemical limitants of photosynthesis. The occurrence of heterogenic photosynthesis caused by patchy stomatal closure in Q. ilex during severe drought should be taken into account in ecosystem modelling in which harsher water stress conditions associated with climate change are predicted.

  1. Studies of variability in Holm oak (Quercus ilex subsp. ballota [Desf.] Samp.) through acorn protein profile analysis.

    Science.gov (United States)

    Valero Galván, José; Valledor, Luis; Navarro Cerrillo, Rafael M; Gil Pelegrín, Eustaquio; Jorrín-Novo, Jesus V

    2011-08-12

    Studies of variability in Holm oak (Quercus ilex subsp. ballota [Desf.] Samp.), the dominant tree species in the typical Mediterranean forest, have been carried out by using electrophoresis-based proteomic analysis of acorns. Ten populations distributed throughout the Andalusia region have been surveyed. Acorns were sampled from individual trees and proteins extracted from seed flour by using the TCA-acetone precipitation protocol. Extracts were subjected to SDS-PAGE and 2-DE for protein separation, gel images captured, spot or bands quantified, and subjected to statistical analysis (ANOVA, SOM and clustering). Variable bands or spots among populations were subjected to MALDI-TOF/TOF and LC-MS/MS for identification. The protein yield of the used protocol varied among populations, and it was in the 2.92-5.92 mg/g dry weight range. A total of 23 bands were resolved by SDS-PAGE in the 3-35 kDa Mr range, with 8 and 12, out of the total, showing respectively qualitative and quantitative statistically significant differences among populations. Data allowed grouping populations, with groups being correlated according to geographical location and climate conditions, to northern and southern, as well as the discrimination of both mesic and xeric groups. Acorn flour extracts from the most distant populations were analyzed by 2-DE, and 56 differential spots were proposed as markers of variability. Identified proteins were classified into two principal categories; storage and stress/defense protein. Besides providing the first reference map of mature acorn seeds, the use of SDS-PAGE and proteomics in characterizing natural biodiversity in forest trees will be discussed. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Spatiotemporal variation in acorn production and damage in a Spanish holm oak (Quercus ilex) dehesa

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Izquierdo, L.; Pulido, F.

    2013-05-01

    Aim of study. There is a lack of knowledge about spatio-temporal patterns of acorn production in dehesas, especially regarding the influence of different agents causing acorn damage. We examined the spatial and temporal variability on acorn production and damage in four stands within a dehesa farm in 1997, 1998 and 1999. Area of study. The study was carried out in a 1800 ha dehesa farm of Caceres province, western Spain. Material and Methods. Acorns were sampled by means of seed traps placed in the canopy of six holm oak trees per stand. Acorn collected in it were counted and assessed for damage by Curculio weevils, Cydia moths and the bacterial pathogen Brenneria quercina. Main results. Mean acorn production for the whole study period was 44.60 acorns m-2, which did not vary significantly either among stands or among years. The variability among individual trees was very high (0-300 acorns m{sup -}2). The rate of infestation by Curculio was 7.64 {+-} 10.72 %, by Cydia was 1.76 {+-}3.33 %, whereas 10.29 {+-} 16.12 % of acorns were infested by Brenneria. We found no significant spatial differences, but the rates of acorn loss by insects varied among years. These rates were independent of annual acorn production and there was no correlation among damages by different pests, except between Curculio and Cydia in two crop years. Research highlights. It can be concluded that acorn crops are synchronized at the within-farm level and that the temporal variation in acorn damages can be independent of crop size. (Author) 49 refs.

  3. [Impact of cork oak management on the ectomycorrhizal fungal diversity associated with Quercus suber in the Mâamora forest (Morocco)].

    Science.gov (United States)

    Maghnia, Fatima Z; Sanguin, Hervé; Abbas, Younes; Verdinelli, Marcello; Kerdouh, Benaissa; El Ghachtouli, Naima; Lancellotti, Enrico; Bakkali Yakhlef, Salah Eddine; Duponnois, Robin

    2017-05-01

    The cork oak forest is an ecosystem playing a major role in Moroccan socio-economy and biodiversity conservation. However, this ecosystem is negatively impacted by extensive human- and climate-driven pressures, causing a strong decrease in its distribution and a worsening of the desertification processes. This study aims at characterising the impact of cork oak forest management on a major actor of its functioning, the ectomycorrhizal (EcM) fungal community associated with Quercus suber, and the determination of EcM bio-indicators. The EcM fungal community has been monitored during spring and winter seasons in two sites of the Moroccan Mâamora forest, corresponding to a forest site either impacted by human activities or protected. A significant impact of cork oak forest management on the EcM fungal community has been revealed, with major differences during the summer season. The results confirmed the potential ecological significance of several EcM fungi (e.g., Cenococcum) in the sustainability of the cork oak forest functioning, but also the significant association of certain EcM fungi (Pachyphloeus, Russula, Tomentella) with a perturbation or a season, and consequently to the cork oak forest status or to climatic conditions, respectively. The development of study at the Mediterranean scale may improve the robustness of ecological models to predict the impact of global changes on this emblematic ecosystem of Mediterranean basin. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

  4. Conductimetric analysis of the ion binding properties of three leaf extracts of chestnut (Castanea sativa), Eucalyptus (Eucalyptus globulus) and oak (Quercus robur).

    Science.gov (United States)

    Rey, F; Pérez-Asenjo, M; Machado, A A; Facal, P; Ferreira, M A; Toja, A

    1995-12-01

    Humic materials extracted from tree leaves of chestnut (Castanea sativa), eucalyptus (Eucalyptus globulus) and oak (Quercus robur) were analyzed by performing conductimetric titrations. Values between about 84 and 236 muS cm(-1) for the molar conductivity and between 0.42 and 0.74 for the charge distribution parameter were obtained when the concentrations of the extract are increased from 40 to 100 mg 1(-1). These variations were explained by using the counterion condensation theory, and the distance between the charged groups of the polyions, the volume of the counterion condensation and the Debye-Hückel potential were also calculated.

  5. Variation of Oriental Oak (Quercus variabilis Leaf δ13C across Temperate and Subtropical China: Spatial Patterns and Sensitivity to Precipitation

    Directory of Open Access Journals (Sweden)

    Baoming Du

    2015-06-01

    Full Text Available The concentration of the carbon-13 isotope (leaf δ13C in leaves is negatively correlated with the mean annual precipitation (MAP atlarge geographical scales. In this paper, we explain the spatial pattern of leaf δ13C variation for deciduous oriental oak (Quercus variabilis Bl. across temperate and subtropical biomes and its sensitivity to climate factors such as MAP. There was a 6‰ variation in the leaf δ13C values of oak with a significant positive correlation with latitude and negative correlations with the mean annual temperature (MAT and MAP. There was no correlation between leaf δ13C and altitude or longitude. Stepwise multiple regression analyses showed that leaf δ13C decreased 0.3‰ per 100 mm increase in MAP. MAP alone could account for 68% of the observed variation in leaf δ13C. These results can be used to improve predictions for plant responses to climate change and particularly lower rainfall.

  6. Population-Level Differentiation in Growth Rates and Leaf Traits in Seedlings of the Neotropical Live Oak Quercus oleoides Grown under Natural and Manipulated Precipitation Regimes

    Directory of Open Access Journals (Sweden)

    Jose A. Ramírez-Valiente

    2017-05-01

    Full Text Available Widely distributed species are normally subjected to spatial heterogeneity in environmental conditions. In sessile organisms like plants, adaptive evolution and phenotypic plasticity of key functional traits are the main mechanisms through which species can respond to environmental heterogeneity and climate change. While extended research has been carried out in temperate species in this regard, there is still limited knowledge as to how species from seasonally-dry tropical climates respond to spatial and temporal variation in environmental conditions. In fact, studies of intraspecific genetically-based differences in functional traits are still largely unknown and studies in these ecosystems have largely focused on in situ comparisons where environmental and genetic effects cannot be differentiated. In this study, we tested for ecotypic differentiation and phenotypic plasticity in leaf economics spectrum (LES traits, water use efficiency and growth rates under natural and manipulated precipitation regimes in a common garden experiment where seedlings of eight populations of the neotropical live oak Quercus oleoides were established. We also examined the extent to which intraspecific trait variation was associated with plant performance under different water availability. Similar to interspecific patterns among seasonally-dry tropical tree species, live oak populations with long and severe dry seasons had higher leaf nitrogen content and growth rates than mesic populations, which is consistent with a “fast” resource-acquisition strategy aimed to maximize carbon uptake during the wet season. Specific leaf area (SLA was the best predictor of plant performance, but contrary to expectations, it was negatively associated with relative and absolute growth rates. This observation was partially explained by the negative association between SLA and area-based photosynthetic rates, which is contrary to LES expectations but similar to other recent

  7. Contrasting nuclear and cytoplasmic exchanges between phylogenetically distant oak species (Quercus suber L. and Q. ilex L.) in Southern France: inferring crosses and dynamics.

    Science.gov (United States)

    Mir, C; Jarne, P; Sarda, V; Bonin, A; Lumaret, R

    2009-03-01

    Gene flow is particularly frequent in the genus Quercus (oaks), especially between closely related species. We focus here on Quercus ilex and the cork-producing Quercus suber, which occasionally hybridize although they are phylogenetically markedly separated. Morphological observations were combined with both allozymic and chloroplastic diagnostic markers to characterize hybridization and introgression and to infer their dynamics in two French regions (French Catalonia and Provence), which are separated by several hundred kilometres. Some hybrids were found in both regions, indicating recent hybridization events. As expected from previous studies, most hybrids resulted from female symbol Q. ilex x male symbol Q. suber crosses, but our data showed that the reciprocal cross is also possible. Partial independence between nuclear and chloroplastic introgression was observed in the two species. Nuclear introgression was limited in both species and both regions, with no preferred direction. In Provence, chloroplastic introgression was very rare in both species. Conversely, all Q. suber individuals from French Catalonia were introgressed by Q. ilex chlorotypes. This might be explained by introgression in the Iberian Peninsula antedating the first occurrence of the two species in French Catalonia. We also observed a new chlorotype that was created locally, and was exchanged between the two species. However, the two species still remain genetically differentiated. The dynamics and complexity of exchanges and the factors determining them (including human management of Q. suber) are discussed.

  8. An investigation on forage yield capacity of kermes oak (Quercus coccifera L.) and grazing planning of Mediterranean maquis scrublands for traditional goat farming.

    Science.gov (United States)

    Tolunay, Ahmet; Adıyaman, Elif; Akyol, Ayhan; İnce, Duygu; Türkoğlu, Türkay; Ayhan, Veysel

    2014-01-01

    This study investigated grazing capacities of maquis scrubland and preparation principles of grazing management in forest resources. Kermes oak (Quercus coccifera L.), which is widespread as a main shrub species in maquis vegetation in Turkey, and pure hair goats (Capra hircus L.) feeding on shoots and leaves of this shrub were selected for study. The study was conducted in two stages. Green leaf and shoot samples were taken from kermes oaks in the first stage and the amount of green herbage yield (g ∗ m(-1)) and dry matter yield (kg ∗ ha(-1)) that may be obtained per unit area from these samples was identified. The considered amount of dry matter consumed by pure hair goats daily and the number of goats being fed within 1 year on land of 1 ha according to different land coverage rates of kermes oaks (goat head ∗ ha ∗ yr) were calculated. In the second stage, grazing capacities of sample areas where kermes oak spread were identified and compared with the grazing plan prepared by the forestry administration for this area. Forage yield variance according to land coverage rates of maquis scrublands should be considered when determining optimum animal numbers for grazing per area for sustainable goat farming.

  9. Drivers of radial growth and carbon isotope discrimination of bur oak (Quercus macrocarpa Michx.) across continental gradients in precipitation, vapour pressure deficit and irradiance

    Science.gov (United States)

    Tree-ring characteristics including stable isotope composition are commonly used to reconstruct climate variables and establish mechanisms that underlie oscillations in modes of climate variability. However, divergence from the assumption of a single, primary biophysical control ...

  10. Biomass and nutrient content of sessile oak (Quercus petraea (Matt.) Liebl.) and beech (Fagus sylvatica L.) stem and branches in a mixed stand in southern Belgium.

    Science.gov (United States)

    André, Frédéric; Jonard, Mathieu; Ponette, Quentin

    2010-05-01

    Accurate estimates of the amounts of nutrients immobilised in the organs and tissues of different tree species are of prime importance to make appropriate tree species selection and determine the harvesting regime that will ensure forest sustainability. Sixteen sessile oaks (Quercus petraea (Matt.) Liebl.) (64-129years; stem diameters: 17-57cm) and twelve beeches (Fagus sylvatica L.) (43-86years; stem diameters: 9-50cm) were destructively sampled from a mixed stand located on an acid brown soil in southern Belgium. Statistical models were developed to investigate the differences in nutrient concentrations between tree species, between aboveground tree compartments of the same species, and between tissues of the same compartment. For stem tissues, vertical concentration profiles were described using a versatile equation. Allometric equations were used to predict biomass and nutrient content of tree compartments based on tree dimensions. Broadly speaking, nutrient concentrations tended to be somewhat higher for oak compared with beech, but the amplitude and the direction of inter-species differences varied greatly, depending on the nutrient and the tree compartment. For both species, living branch nutrient concentrations tended to decrease with increasing branch diameter, except for Ca (oak) and Mg (beech). Nutrient concentrations were consistently higher in bark than in wood; this difference between tissues was quite pronounced for Ca, particularly in the case of oak. The biomass and nutrient content equations were used to investigate the effects of tree species and harvesting regime on nutrient exports at harvesting. For equivalent harvesting scenarios, beech was found to induce higher Mg exports than oak, and inversely for Ca. Assuming stand clear cutting, complete tree harvesting would increase average nutrient exports from 65% (Ca) to 162% (P) compared with a stem-only harvesting scenario. These results provide valuable information in the current context of the

  11. Genetic consequences of habitat fragmentation in long-lived tree species: the case of the mediterranean Holm Oak (Quercus ilex, L.).

    Science.gov (United States)

    Ortego, Joaquín; Bonal, Raúl; Muñoz, Alberto

    2010-01-01

    Large-scale forest fragmentation can increase interpopulation genetic differentiation and erode the genetic variability of remnant plant populations. In this study, we analyze the extent of clonality and the genetic variability and structure within a holm oak (Quercus ilex) population from Central Spain at 3 patches showing different degrees of fragmentation. For this purpose, we have typed 191 individuals (105 adults and 86 saplings) at 9 microsatellite loci. Microsatellite markers revealed an extensive clonal structure in this species, with most analyzed clumps constituting a single "genet", which in some cases extended over a considerable area (up to 318 m(2)). The maximum distance between "ramets" tended to be higher in the extremely fragmented patch, suggesting that intensive management and environmental perturbation has favored clonal propagation. We have also found evidence that fragmentation has contributed to reduce genetic variability and increase genetic differentiation in holm oak saplings, indicating that the younger cohorts are suffering some negative genetic consequences of long-term population fragmentation. Finally, analyses of fine spatial genetic structure have revealed significant kinship structures up to 20-50 m that were particularly patent in the 2 less fragmented patches. Overall, our findings point to long-term genetic shifts in population structure of holm oaks in fragmented landscapes; however, further research is required on pollen dispersal and gene flow in this species.

  12. Chloroplast DNA analysis of Tunisian cork oak populations (Quercus suber L.): sequence variations and molecular evolution of the trnL (UAA)-trnF (GAA) region.

    Science.gov (United States)

    Abdessamad, A; Baraket, G; Sakka, H; Ammari, Y; Ksontini, M; Hannachi, A Salhi

    2016-10-24

    Sequences of the trnL-trnF spacer and combined trnL-trnF region in chloroplast DNA of cork oak (Quercus suber L.) were analyzed to detect polymorphisms and to elucidate molecular evolution and demographic history. The aligned sequences varied in length and nucleotide composition. The overall ratio of transition/transversion (ti/tv) of 0.724 for the intergenic spacer and 0.258 for the pooled sequences were estimated, and indicated that transversions are more frequent than transitions. The molecular evolution and demographic history of Q. suber were investigated. Neutrality tests (Tajima's D and Fu and Li) ruled out the null hypothesis of a strictly neutral model, and Fu's Fs and Ramos-Onsins and Rozas' R2 confirmed the recent expansion of cork oak trees, validating its persistency in North Africa since the last glaciation during the Quaternary. The observed uni-modal mismatch distribution and the Harpending's raggedness index confirmed the demographic history model for cork oak. A phylogenetic dendrogram showed that the distribution of Q. suber trees occurs independently of geographical origin, the relief of the population site, and the bioclimatic stages. The molecular history and cytoplasmic diversity suggest that in situ and ex situ conservation strategies can be recommended for preserving landscape value and facing predictable future climatic changes.

  13. Code Generation = A* + BURS

    NARCIS (Netherlands)

    Nymeyer, Albert; Katoen, Joost P.; Westra, Ymte; Alblas, H.; Gyimóthy, Tibor

    1996-01-01

    A system called BURS that is based on term rewrite systems and a search algorithm A* are combined to produce a code generator that generates optimal code. The theory underlying BURS is re-developed, formalised and explained in this work. The search algorithm uses a cost heuristic that is derived

  14. Phenotypic variation in California populations of valley oak (Quercus lobata Née) sampled along elevational gradients

    Science.gov (United States)

    Ana L. Albarrán-Lara; Jessica W. Wright; Paul F. Gugger; Annette Delfino-Mix; Juan Manuel Peñaloza-Ramírez; Victoria L. Sork

    2015-01-01

    California oaks exhibit tremendous phenotypic variation throughout their range. This variation reflects phenotypic plasticity in tree response to local environmental conditions as well as genetic differences underlying those phenotypes. In this study, we analyze phenotypic variation in leaf traits for valley oak adults sampled along three elevational transects and in...

  15. Response of naturally regenerated and underplanted white oak (Quercus alba L.) seedlings 6 years following midstory removal

    Science.gov (United States)

    Jared M. Craig; John M. Lhotka; Jeffrey W. Stringer

    2013-01-01

    Historically, the abundance of red maple and shade-tolerant understory species was limited by fire and other disturbances. In the absence of periodic disturbance, regeneration of oaks with intermediate shade tolerance has been hindered due to inadequate light conditions created by shade-tolerant midstory trees. Research suggests that midstory removal in oak-dominated...

  16. Contrasting ecophysiological strategies related to drought: the case of a mixed stand of Scots pine (Pinus sylvestris) and a submediterranean oak (Quercus subpyrenaica).

    Science.gov (United States)

    Martín-Gómez, Paula; Aguilera, Mònica; Pemán, Jesús; Gil-Pelegrín, Eustaquio; Ferrio, Juan Pedro

    2017-10-13

    Submediterranean forests are considered an ecotone between Mediterranean and Eurosiberian ecosystems, and are very sensitive to global change. A decline of Scots pine (Pinus sylvestris L.) and a related expansion of oak species (Quercus spp.) have been reported in the Spanish Pre-Pyrenees. Although this has been associated with increasing drought stress, the underlying mechanisms are not fully understood, and suitable monitoring protocols are lacking. The aim of this study is to bring insight into the physiological mechanisms anticipating selective decline of the pines, with particular focus on carbon and water relations. For this purpose, we performed a sampling campaign covering two growing seasons in a mixed stand of P. sylvestris and Quercus subpyrenaica E.H del Villar. We sampled seasonally twig xylem and soil for water isotope composition (δ18O and δ2H), leaves for carbon isotope composition (δ13C) and stems to quantify non-structural carbohydrates (NSC) concentration, and measured water potential and leaf gas exchange. The first summer drought was severe for both species, reaching low predawn water potential (-2.2 MPa), very low stomatal conductance (12 ± 1.0 mmol m-2 s-1) and near-zero or even negative net photosynthesis, particularly in P. sylvestris (-0.6 ± 0.34 μmol m-2 s-1 in oaks, -1.3 ± 0.16 μmol m-2 s-1 in pines). Hence, the tighter stomatal control and more isohydric strategy of P. sylvestris resulted in larger limitations on carbon assimilation, and this was also reflected in carbon storage, showing twofold larger total NSC concentration in oaks than in pines (7.8 ± 2.4% and 4.0 ± 1.3%, respectively). We observed a faster recovery of predawn water potential after summer drought in Q. subpyrenaica than in P. sylvestris (-0.8 MPa and -1.1 MPa, respectively). As supported by the isotopic data, this was probably associated with a deeper and more reliable water supply in Q. subpyrenaica. In line with these short-term observations, we found a

  17. Analysis of pubescent oak (Quercus pubescens Willd. by means of chloroplast DNA (cpDNA in the western part of the Balkan Peninsula

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    Dalibor Ballian

    2011-01-01

    Full Text Available In the area of the western Balkans, xerothermal broad-leaf forests hold a very special position, the main species being pubescent oak (Quercus pubescens Willd.. The study comprises 36 populations of pubescent oak from Croatia, Bosnia and Herzegovina, Montenegro, Kosovo, Albania and Macedonia. Genetic variability and population diversity was analysed on chloroplast DNA in order to determine to which haplotype an individual or studied population belongs, as well as how they are related. For the detection of one haplotype analysed four sequences (AS, TF, DT and CD on the chloroplasts DNA. The results of the analysis suggest that there are six different haplotypes of pubescent oak (2, 4, 5, 17, 31, 33 in the studied populations. Two more sub-haplotypes were found in haplotype 5 (a and b, but only in populations occurring in Croatia and Bosnia and Herzegovina. The results suggest the great variability of pubescent oak in the researched area, which is generally characteristic of other species from the area of the Balkan Peninsula. The results obtained by means of cpDNA analysis can help in the formation of seed zones. However, due to the strong selection pressure of unplanned logging, and the possible introduction of herbal material of unknown origin, it is necessary to find a sufficient number of autochthonous entities (i.e., populations of the researched species as well as new suitable markers for their characterization. The results of this paper constitute a scientifically recognised, partial examination of the origin of the starting forest reproductive material from the broader geographic area, thus serving future projects on its regeneration.

  18. Effects of Different Levels of Raw and Processed Oak Acorn (Quercus castaneifolia on Performance, Small Intestine Morphology, Ileal Digestibility of Nutrients, Carcass Characteristics and Some Blood Parameters in Broiler Chickens

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    Rezaie M

    2016-12-01

    Full Text Available This study was conducted to determine the effect of oak acorn (Quercus castaneifolia on performance, small intestine morphology, ileal digestibility of nutrient, carcass and some blood parameters in broiler chicks. A total of fifty hundred four one-d old male chickens (Ross308 strain with seven treatments and four replicates in each treatment were used. Experimental diets were: control (corn-soybean meal diet, raw oak acorn at the levels of 10 and 20 percent, soaked oak acorn diet containing 10 and 20 percent oak acorn soaked in water for 24h., diets contain 10 and 20 percent of soaked oak acorn soaked in water for 48h with twice water substitution. Experiment lasted from 1 to 42 day of ages. Results showed that body weight, weight gain, feed intake, feed conversion ratio, ileal dry matter and protein digestibility, and small intestine morphology was significantly (P

  19. Changes in water status and proline and abscisic acid concentrations in developing somatic embryos of pedunculate oak (Quercus robur) during maturation and germination.

    Science.gov (United States)

    Prewein, Christine; Vagner, Martin; Wilhelm, Eva

    2004-11-01

    Somatic embryos of oak (Quercus robur L.) were matured on P24 media differing in gel strength (0.8, 0.9 and 1.0% (w/v) agar). Viscosity and osmotic potential (Psipi,medium) of the media were determined. Developing cotyledonary embryos were analyzed at maturity Stages I-III for water content, osmotic potential (Psipi,embryo) and concentrations of abscisic acid (ABA) and proline. Proliferation of embryogenic tissue, germination rates and the number of embryos formed were also determined in order to relate embryo quality to physiological parameters. Viscosity increased with agar concentration, a phenomenon apparently related to water availability. Many Stage III embryos with high germination potentials were obtained on P24 medium containing 1.0% agar. Embryo water content decreased progressively from 94 to 80% during embryo maturation. Stage I and II embryos that matured on media containing 0.8 or 0.9% agar had similar values of Psipi,embryo, whereas Psipi,embryo of Stage III embryos that matured on medium containing 1.0% agar was significantly lower, although Psipi,medium was unaffected by gel strength. Stage III embryos showed a nearly 16-fold increase in proline concentration and a 50% decrease in ABA concentration compared with Stage I embryos. We conclude that tissue water status and a complex relationship between ABA and proline concentrations, modulated by medium gel strength, are important factors in the maturation process and the quality of oak somatic embryos.

  20. Evidence on the Adaptive Recruitment of Chinese Cork Oak (Quercus variabilis Bl.: Influence on Repeated Germination and Constraint Germination by Food-Hoarding Animals

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    Yifeng Zhang

    2016-02-01

    Full Text Available In drought temperate forest, seedling recruitment is highly dependent on seed burial by native animal dispersers. To prolong seed storage, animals often take measures to impede seed germination. Aiming to understand the strategic balance between the natural seed germination and the role played by animals in the constraint germination procedures, we investigated the stages on the germinated acorns of Chinese cork oak (Quercus variabilis Bl. and the rodents’ behavior on the consequential delay in developmental processes of acorns in Mt. Taihangshan area of Jiyuan, Henan, China. The results showed that (1 Apodemus peninsulae Thomas excise radicles from germinated acorns before hoarding; (2 radicle-excised acorns re-germinate successfully if the excised radicle was un-lignified, but reverse if excised radicle was lignified; and (3 seedlings derived from radicle-excised acorns produce more lateral roots than that of sound acorns. We conclude that rodents take the radicle-excision behavior as a deliberate mechanism to slow the rapid germination of acorns; nevertheless, the acorns adaptively respond to this negative treatment and counteract the constraint from rodents by regermination to preserve the viability of the seeds. Consequently, this plays a significant role in forest recruitment. This study proves the new survival model of Chinese cork oak against animal predation, and will broaden theories of animal-forest interaction, forest succession and can be used as a meaningful venture to temperate forest restoration efforts.

  1. Seasonal and diurnal variability in sap flow intensity of mature sessile oak (Quercus petraea (Matt.) Liebl.) trees in relation to microclimatic conditions.

    Science.gov (United States)

    Kanalas, P; Fenyvesi, A; Kis, J; Szöllösi, Erzsébet; Oláh, V; Ander, I; Mészáros, Ilona

    2010-01-01

    In this study sap flow dynamics of mature sessile oak trees (Quercus petraea) in a marginal sessile oak-turkey oak forest was investigated in 2009. That year spring was dry without significant rain in April and May and the driest month was August. Due to the extreme weather conditions the volumetric soil water content (SWC) of upper 30 cm was low on experimental days in May (0.13-0.14 cm3 cm-3) but it reached the lowest value in August (0.08 cm3 cm-3). Sap flow was measured in a dominant and a co-dominant tree by heat dissipation method from 26 March till 30 October. In the present paper several three-day long periods of the continuous seasonal recordings were chosen to represent the effects of typical weather conditions and different stages of canopy development on sap flow dynamics. The daily maximum sap flow density values of dominant and co-dominant trees were similar (0.30-0.32 cm3 cm-2 min-1) in moist period (July). Rains and transient increase of SWC after proceeding drought resulted in change of diurnal course of sap flow in experimental days of July. In this period dominant trees also showed considerable sap flow (0.19 cm3 cm-2 min-1) during night hours and short sap flow peaks in early morning (6:00 to 8:00 a.m.) indicating the refilling of desiccated tissues. After the progressive drought in August the daily maximum sap flow density decreased to 0.07 cm3 cm-2 min-1 in dominant tree and to 0.12 cm3 cm-2 min-1 in the co-dominant. Both trees exhibited gradual stomatal closure from morning hours.

  2. Biomass, Carbon and Nutrient Storage in a 30-Year-Old Chinese Cork Oak (Quercus Variabilis Forest on the South Slope of the Qinling Mountains, China

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    Yang Cao

    2015-04-01

    Full Text Available Chinese cork oak (Quercus variabilis forests are protected on a large-scale under the Natural Forest Protection (NFP program in China to improve the ecological environment. However, information about carbon (C storage to increase C sequestration and sustainable management is lacking. Biomass, C, nitrogen (N and phosphorus (P storage of trees, shrubs, herb, litter and soil (0–100 cm were determined from destructive tree sampling and plot level investigation in approximately 30-year old Chinese cork oak forests on the south slope of the Qinling Mountains. There was no significant difference in tree components’ biomass estimation, with the exception of roots, among the available allometric equations developed from this study site and other previous study sites. Leaves had the highest C, N and P concentrations among tree components and stems were the major compartments for tree biomass, C, N and P storage. In contrast to finding no difference in N concentrations along the whole soil profile, higher C and P concentrations were observed in the upper 0–10 cm of soil than in the deeper soil layers. The ecosystem C, N, and P storage was 163.76, 18.54 and 2.50 t ha−1, respectively. Soil (0–100 cm contained the largest amount of C, N and P storage, accounting for 61.76%, 92.78% and 99.72% of the total ecosystem, followed by 36.14%, 6.03% and 0.23% for trees, and 2.10%, 1.19% and 0.03% for shrubs, herbs and litter, respectively. The equations accurately estimate ecosystem biomass, and the knowledge of the distribution of C, N and P storage will contribute to increased C sequestration and sustainable management of Chinese cork oak forests under the NFP program.

  3. Differences in photosynthesis and isoprene emission in post oak (Quercus stellata) and sweetgum (Liquidambar styraciflua) trees along an urban-to-rural gradient in Texas

    Science.gov (United States)

    Crossett, C.; Lahr, E.; Haas, G.; Schade, G. W.

    2014-12-01

    Many plants produce isoprene, a volatile organic compound that can mitigate damage to photosynthetic systems during short- or long-term increases in leaf temperature. After its production within leaves, isoprene is emitted to the atmosphere and influences regional atmospheric chemistry. Here, we use an urban-to-rural gradient to explore future effects of climate change on tree eco-physiology and feedbacks to atmospheric chemistry. Urban areas mimic many of the conditions expected to occur in the future; in particular, cities have warmer temperatures due to the urban heat island (UHI) effect, and less water availability relative to rural areas. Along a 90 km urban-to-rural gradient, we measured photosynthesis and isoprene emission from trees at three sites in eastern Texas: Houston (urban), The Woodlands (suburban) and Sam Houston National Forest (rural). Isoprene emission from post oak (Quercus stellata) was higher in Houston than the other sites, and when leaf temperatures were increased above ambient conditions, trees produced more isoprene. Leaves produced more isoprene at high leaf temperatures in early summer than in late summer, suggesting gradual acclimation of photosynthetic processes over the course of the summer. We also found that sweetgum (Liquidambar styraciflua) emitted more isoprene than post oak, but when leaf temperatures were increased, isoprene emission was exhausted more quickly in sweetgum relative to post oak. At the same time, post oak maintained higher levels of photosynthesis seasonally and during short-term temperature increases. Both post oak and sweetgum are significant isoprene emitters and represent approximately two and four percent crown cover in the United States, respectively. Our results suggest that in a warming climate, we can expect trees to produce more isoprene seasonally and in response to short-term temperature extremes, and that species-specific differences in photosynthesis and isoprene emission may play an important role

  4. Evaluation of the degree of healthiness of the pedunculate oak (Quercus robur L. acorns in the Włoszczowa– Jędrzejów Nature Park and its neighbouring area

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    Bąk-Badowska Jolanta

    2017-03-01

    Full Text Available The aim of the study was to demonstrate the degree of healthiness of the pedunculate oak (Quercus robur acorns found in the Włoszczowa-Jędrzejów Nature Park (abbreviation: W-JOChK and in the neighbouring area. It was dealt with by making the analysis of health of the acorns (total 3,600. The research material included the samples of fallen down acorns, collected under the pedunculate oaks in Kurzelów (W-JOChK, as well as Żelisławice. The study was conducted from late September 2014 to early October 2015.

  5. Establishment limitation of holm oak (Quercus ilex subsp. Ballota (Desf.) Samp.) in a Mediterranean savanna - forest ecosystem

    NARCIS (Netherlands)

    Smit, C.; Díaz, M.; Jansen, P.A.

    2009-01-01

    ¿Tree recruitment in Mediterranean savannas is generally hampered, in contrast with the original oak forests where these savannas are derived from. We asked whether this difference in recruitment success can be explained by differential post-dispersal survival. For one year we monitored

  6. Establishment limitation of holm oak (Quercus ilex subsp ballota (Desf.) Samp.) in a Mediterranean savanna - forest ecosystem

    NARCIS (Netherlands)

    Smit, Christian; Diaz, Mario; Jansen, Patrick

    2009-01-01

    Tree recruitment in Mediterranean savannas is generally hampered, in contrast with the original oak forests where these savannas are derived from. We asked whether this difference in recruitment success can be explained by differential post-dispersal survival. For one year we monitored

  7. Age-related variation in carbon allocation at tree and stand scales in beech (Fagus sylvatica L.) and sessile oak (Quercus petraea (Matt.) Liebl.) using a chronosequence approach.

    Science.gov (United States)

    Genet, H; Bréda, N; Dufrêne, E

    2010-02-01

    Two types of physiological mechanisms can contribute to growth decline with age: (i) the mechanisms leading to the reduction of carbon assimilation (input) and (ii) those leading to modification of the resource economy. Surprisingly, the processes relating to carbon allocation have been little investigated as compared to research on the processes governing carbon assimilation. The objective of this paper was thus to test the hypothesis that growth decrease related to age is accompanied by changes in carbon allocation to the benefit of storage and reproductive functions in two contrasting broad-leaved species: beech (Fagus sylvatica L.) and sessile oak (Quercus petraea (Matt.) Liebl.). Age-related changes in carbon allocation were studied using a chronosequence approach. Chronosequences, each consisting of several even-aged stands ranging from 14 to 175 years old for beech and from 30 to 134 years old for sessile oak, were divided into five or six age classes. In this study, carbon allocations to growth, storage and reproduction were defined as the relative amount of carbon invested in biomass increment, carbohydrate increment and seed production, respectively. Tree-ring width and allometric relationships were used to assess biomass increment at the tree and stand scales. Below-ground biomass was assessed using a specific allometric relationship between root:shoot ratio and age, established from the literature review. Seasonal variations of carbohydrate concentrations were used to assess carbon allocation to storage. Reproduction effort was quantified for beech stands by collecting seed and cupule production. Age-related flagging of biomass productivity was assessed at the tree and stand scales, and carbohydrate quantities in trees increased with age for both species. Seed and cupule production increased with stand age in beech from 56 gC m(-)(2) year(-1) at 30 years old to 129 gC m(-2) year(-1) at 138 years old. In beech, carbon allocation to storage and

  8. A model to account for variations in holm-oak (Quercus ilex subsp. ballota) acorn production in southern Spain.

    Science.gov (United States)

    García-Mozo, Herminia; Dominguez-Vilches, Eugenio; Galán, Carmen

    2012-01-01

    One of the characteristics of holm-oak acorn production is its high variability among individuals and years. To examine the main causes of this fact, a study was conducted from 1998-2010 in a natural area of holm-oak in southern Spain, where floral phenology, fruit production, fruit size, airborne pollen emission and meteorology factors were analyzed with the ultimate aim of developing a model for forecasting holm-oak yield. Pollen emission during flowering season was the main factor determining the final acorn harvest, but also some meteorological variables played an important role in explaining acorn crop variations, especially humidity and temperature during the months of April and September. The reliability of the proposed model was externally validated using data not included in its construction; validation yielded acceptable results, with a minimum error of estimation. Our results appear to be very useful for planning cropping and pig feeding strategies. Further research could extend the use of airborne pollen counts in forest studies relating to anemophilous species, in order to optimize agricultural policies.

  9. Differential radial growth patterns between beech (Fagus sylvatica L.) and oak (Quercus robur L.) on periodically waterlogged soils.

    Science.gov (United States)

    Scharnweber, Tobias; Manthey, Michael; Wilmking, Martin

    2013-04-01

    Climate scenarios for northern Central Europe project rising temperatures and increasing frequency and intensity of droughts but also a shift in precipitation pattern with more humid winters. This in turn may result in soil waterlogging during the following spring, leading to increasing stress for trees growing on hydric sites. The influence of waterlogging on growth of common beech and pedunculate oak has been studied intensively on seedlings under experimental conditions. However, the question remains whether results of these studies can be transferred to mature trees growing under natural conditions. To test this, we investigated general growth patterns and climate-growth relationships in four mature stands of beech and oak growing on hydromorphic soils (Stagnosols) in northeast Germany using dendrochronological methods. Our results confirmed the expected tolerance of oak to strong water-level fluctuations. Neither extremely wet conditions during spring nor summer droughts significantly affected its radial growth. Oak growth responded positively to warmer temperatures during previous year October and March of the current year of ring formation. Contrary to our expectations, also beech showed relatively low sensitivity to periods of high soil water saturation. Instead, summer drought turned out to be the main climatic factor influencing ring width of beech even under the specific periodically wet soil conditions of our study. This became evident from general climate-growth correlations over the last century as well as from discontinuous (pointer year) analysis with summer drought being significantly correlated to the occurrence of growth depressions. As ring width of the two species is affected by differing climate parameters, species-specific chronologies show no coherence in high-frequency variations even for trees growing in close proximity. We assume differences in rooting depth as the main reason for the differing growth patterns and climate correlations of

  10. In Situ Dark Adaptation Enhances the Efficiency of DNA Extraction from Mature Pin Oak (Quercus palustris Leaves, Facilitating the Identification of Partial Sequences of the 18S rRNA and Isoprene Synthase (IspS Genes

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    Csengele E. Barta

    2017-10-01

    Full Text Available Mature oak (Quercus spp. leaves, although abundantly available during the plants’ developmental cycle, are rarely exploited as viable sources of genomic DNA. These leaves are rich in metabolites difficult to remove during standard DNA purification, interfering with downstream molecular genetics applications. The current work assessed whether in situ dark adaptation, to deplete sugar reserves and inhibit secondary metabolite synthesis could compensate for the difficulties encountered when isolating DNA from mature leaves rich in secondary metabolites. We optimized a rapid, commercial kit based method to extract genomic DNA from dark- and light-adapted leaves. We demonstrated that in situ dark adaptation increases the yield and quality of genomic DNA obtained from mature oak leaves, yielding templates of sufficiently high quality for direct downstream applications, such as PCR amplification and gene identification. The quality of templates isolated from dark-adapted pin oak leaves particularly improved the amplification of larger fragments in our experiments. From DNA extracts prepared with our optimized method, we identified for the first time partial segments of the genes encoding 18S rRNA and isoprene synthase (IspS from pin oak (Quercus palustris, whose full genome has not yet been sequenced.

  11. Capturing forest dependency in the central Himalayan region: Variations between Oak (Quercus spp.) and Pine (Pinus spp.) dominated forest landscapes.

    Science.gov (United States)

    Chakraborty, Anusheema; Joshi, Pawan Kumar; Sachdeva, Kamna

    2017-10-05

    Our study explores the nexus between forests and local communities through participatory assessments and household surveys in the central Himalayan region. Forest dependency was compared among villages surrounded by oak-dominated forests (n = 8) and pine-dominated forests (n = 9). Both quantitative and qualitative analyses indicate variations in the degree of dependency based on proximity to nearest forest type. Households near oak-dominated forests were more dependent on forests (83.8%) compared to households near pine-dominated forests (69.1%). Forest dependency is mainly subsistence-oriented for meeting basic household requirements. Livestock population, cultivated land per household, and non-usage of alternative fuels are the major explanatory drivers of forest dependency. Our findings can help decision and policy makers to establish nested governance mechanisms encouraging prioritized site-specific conservation options among forest-adjacent households. Additionally, income diversification with respect to alternate livelihood sources, institutional reforms, and infrastructure facilities can reduce forest dependency, thereby, allowing sustainable forest management.

  12. Stem hydraulic capacitance decreases with drought stress: implications for modelling tree hydraulics in the Mediterranean oak Quercus ilex.

    Science.gov (United States)

    Salomón, Roberto L; Limousin, Jean-Marc; Ourcival, Jean-Marc; Rodríguez-Calcerrada, Jesús; Steppe, Kathy

    2017-08-01

    Hydraulic modelling is a primary tool to predict plant performance in future drier scenarios. However, as most tree models are validated under non-stress conditions, they may fail when water becomes limiting. To simulate tree hydraulic functioning under moist and dry conditions, the current version of a water flow and storage mechanistic model was further developed by implementing equations that describe variation in xylem hydraulic resistance (R X ) and stem hydraulic capacitance (C S ) with predawn water potential (Ψ PD ). The model was applied in a Mediterranean forest experiencing intense summer drought, where six Quercus ilex trees were instrumented to monitor stem diameter variations and sap flow, concurrently with measurements of predawn and midday leaf water potential. Best model performance was observed when C S was allowed to decrease with decreasing Ψ PD . Hydraulic capacitance decreased from 62 to 25 kg m -3  MPa -1 across the growing season. In parallel, tree transpiration decreased to a greater extent than the capacitive water release and the contribution of stored water to transpiration increased from 2.0 to 5.1%. Our results demonstrate the importance of stored water and seasonality in C S for tree hydraulic functioning, and they suggest that C S should be considered to predict the drought response of trees with models. © 2017 John Wiley & Sons Ltd.

  13. Increased drying rate lowers the critical water content for survival in embryonic axes of English oak (Quercus robur L.) seeds.

    Science.gov (United States)

    Ntuli, Tobias M; Finch-Savage, William E; Berjak, Patricia; Pammenter, Norman W

    2011-04-01

    The potential to cryopreserve embryonic axes of desiccation-sensitive (recalcitrant) seeds is limited by damage during the desiccation necessary for low temperature survival, but the basis of this injury and how to reduce it is not well understood. The effects of drying rate on the viability, respiratory metabolism and free radical-mediated processes were therefore investigated during dehydration of Quercus robur L. embryonic axes. Viability, assessed by evidence of germination and tetrazolium staining, showed a sharp decline at 0.27 and 0.8 g/g during rapid (<12 h) or slow (3 d) dehydration, respectively. Rapid dehydration therefore lowered the critical water content for survival. At any given water content rapid dehydration was associated with higher activities of the free radical processing enzymes, superoxide dismutase, catalase and glutathione reductase and lower levels of hydroperoxide and membrane damage. Rapid dehydration was also associated with lower malate dehydrogenase activity, and a reduced decline in phosphofructokinase activity and in levels of the oxidized form of nicotinamide dinucleotide. Ageing may have contributed to increased damage during slow dehydration, since viability declined even in hydrated storage after 3 d. The results presented are consistent with rapid dehydration reducing the accumulation of damage resulting from desiccation induced aqueous-based deleterious reactions. © 2011 Institute of Botany, Chinese Academy of Sciences.

  14. Seed Biology and Technology of Quercus

    Science.gov (United States)

    F.T. Bonner; John A. Vozzo

    1987-01-01

    The genus Quercus,known as oak, includes worldwide some 500 species with 58 of these species in the United States, making it this country's largest genus of native trees (Little 1979). Oak is therefore an important group of temperate-zone forest trees. In addition, oaks are significant components of many of the major forest types of the South (Burns 1983)and are...

  15. Effects of fire temperature on the physical and chemical characteristics of the ash from two plots of Cork oak (Quercus Suber)

    Science.gov (United States)

    Ubeda, X.; Pereira, P.; Outeiro, L.; Martin, D.A.

    2009-01-01

    Cork oak, (Quercus suber) is widely distributed in the Mediterranean region, an area subject to frequent fires. The ash produced by burning can have impacts on the soil status and water resources that can differ according to the temperature reached during fire and the characteristics of the litter, defined as the dead organic matter accumulated on the soil surface prior to the fire. The aim of this work is to determine the physical and chemical characteristics of ash produced in laboratory experiments to approximate conditions typical of fires in this region. The litter of Quercus suber collected from two different plots on the Iberian Peninsula, Mas Bassets (Catalonia) and Albufeira (Portugal), was combusted at different temperatures for 2h. We measured Mass Loss (ML per cent), ash colour and CaCO3 content, pH, Electrical Conductivity (EC) and the major cations (Ca2+, Mg2+, K+ and Na+) released from ash slurries created by mixing ash with deionized water. The results showed that ML per cent is higher at all temperatures in Albufeira samples compared to Mas Bassets samples, except at 550??C, and the rate of loss increases faster with temperature than the Mas Bassets samples. At 150??C the ash colour is yellowish, becoming reddish at 200- 250??C and black at 300??C. Above 400??C the ash is grey/white. This thermal degradation is mostly observed in Albufeira litter. The formation of CaCO3 was identified at a lower temperature in Albufeira litter. At temperatures soil properties are observed at medium and higher temperatures. These negative effects include a higher percentage of mass loss, meaning more soil may be exposed to erosion, higher pH values and greater cation release from ash, especially monovalalent cations (K+,Na+) in higher proportions than the divalent ions (Ca2+, Mg2+), that can lead to impacts on soil physical properties like aggregate stability. Furthermore, the ions in ash may alter soil chemistry which may be detrimental to some plants thus altering

  16. Identification and sensory evaluation of dehydro- and deoxy-ellagitannins formed upon toasting of oak wood (Quercus alba L.).

    Science.gov (United States)

    Glabasnia, Arne; Hofmann, Thomas

    2007-05-16

    Traditionally, spirits such as whiskey are matured in toasted wood barrels to improve the sensory quality of the final beverage. In order to gain first insight into the puzzling road map of thermal ellagitannin transformation chemistry and provide evidence for the changes in sensory active nonvolatiles in oak wood during toasting, the purified oak ellagitannins castalagin and vescalagin, their corresponding dimers roburin A and roburin D, and 33-carboxy-33-deoxyvescalagin were thermally treated in model experiments. Besides mouth-coating and golden-brown colored melanoidin-type polymers, individual major reaction products were produced as transient intermediates which were identified for the first time by means of LC-MS/MS and 1D/2D-NMR spectroscopy. Depending strongly on the stereochemistry, castalagin is oxidized to the previously unreported dehydrocastalagin, whereas its diastereomer vescalagin, differing only in the stereochemistry at carbon C-1, is most surprisingly converted into deoxyvescalagin. Comparative model experiments with 33-carboxy-33-deoxyvescalagin revealed castalagin, vescalagin, dehydrocastalagin, and deoxyvescalagin as typical reaction products, thus indicating decarboxylation as a key step in the thermal degradation of that ellagitannin. Similar to the ellagitannin monomers, LC-MS/MS analyses gave strong evidence that the corresponding dimer roburin A, containing the vescalagin configuration at C-1, was converted into the deoxyroburin A, whereas roburin D, exhibiting the castalagin configuration at C-1, was oxidized to give the dehydroroburin D. Human sensory experiments revealed that the ellagitannin derivatives imparted an astringent mouth-coating sensation with threshold concentrations ranging from 1.1 to 126.0 micromol/L, depending strongly on their chemical structure.

  17. Ancient and current gene flow between two distantly related Mediterranean oak species, Quercus suber and Q. ilex.

    Science.gov (United States)

    Lumaret, Roselyne; Jabbour-Zahab, Roula

    2009-09-01

    Quercus suber and Q. ilex are distantly related and their distributions partially overlap. They hybridize occasionally, but the complete replacement of Q. suber chloroplast DNA (cpDNA) by that of Q. ilex was identified in two specific geographical areas. The objective of this study was to determine whether the contrasting situation reflected current or recent geographical interspecies gene flow variation or was the result of ancient introgression. cpDNA PCR-RFLPs (restriction fragment length polymorphisms) and variation at ten nuclear microsatellite loci were analysed in populations of each species, in 16 morphologically intermediate individuals and the progeny of several of them. Interspecies nuclear introgression was based on individual admixture rates using a Bayesian approach with no a priori species assignment, and on a maximum-likelihood (ML) method, using allele frequencies in the allopatric populations of each species as controls. Gene flow was compared specifically between populations located within and outside the specific areas. High interspecies nuclear genetic differentiation was observed, with twice the number of alleles in Q. ilex than in Q. suber. According to Bayesian assignment, approx. 1 % of individuals had a high probability of being F(1) hybrids, and bidirectional nuclear introgression affected approx. 4 % of individuals in each species. Hybrid and introgressed individuals were identified predominantly in mixed stands and may have a recent origin. Higher proportions including allospecific genes recovered from past hybridization were obtained using the ML method. Similar rates of hybridization and of nuclear introgression, partially independent of cpDNA interspecies transfer suggestive of gene filtering, were obtained in the populations located within and outside the areas of complete cpDNA replacement. The results did not provide evidence for geographical variation in interspecies gene flow. In contrast, historical introgression is supported

  18. A new attempt at discrimination between Quercus petraea and Quercus robur based on wood anatomy

    OpenAIRE

    Feuillat, François; Dupouey, Jean-Luc; Sciama, Delphine; Keller, René

    1997-01-01

    The interspecific variability of wood anatomy between the two major oak species Quercus robur L. and Quercus petraea (Matt.) Liebl. is still largely unknown. However, anatomy strongly influences the technological properties of wood and the ecophysiological functioning of trees. Moreover, identification of oak wood species is a long-standing challenge and important for many purposes. In the Cîteaux Forest (Burgundy), 58 oaks from 14 mixed stands were sampled for wood anatomy characterization. ...

  19. Evolutionary trade-offs between drought resistance mechanisms across a precipitation gradient in a seasonally dry tropical oak (Quercus oleoides).

    Science.gov (United States)

    Ramírez-Valiente, Jose A; Cavender-Bares, Jeannine

    2017-07-01

    In seasonally dry tropical forest regions, drought avoidance during the dry season coupled with high assimilation rates in the wet season is hypothesized to be an advantageous strategy for forest trees in regions with severe and long dry seasons. In contrast, where dry seasons are milder, drought tolerance coupled with a conservative resource-use strategy is expected to maximize carbon assimilation throughout the year. Tests of this hypothesis, particularly at the intraspecific level, have been seldom conducted. In this study, we tested the extent to which drought resistance mechanisms and rates of carbon assimilation have evolved under climates with varying dry season length and severity within Quercus oleoidesCham. and Schlect., a tropical dry forest species that is widely distributed in Central America. For this purpose, we conducted a greenhouse experiment where seedlings originating from five populations that vary in rainfall patterns were grown under different watering treatments. Our results revealed that populations from xeric climates with more severe dry seasons exhibited large mesophyllous leaves (with high specific leaf area, SLA), and leaf abscission in response to drought, consistent with a drought-avoidance strategy. In contrast, populations from more mesic climates with less severe dry seasons had small and thick sclerophyllous leaves with low SLA and reduced water potential at the turgor loss point (πtlp), consistent with a drought-tolerance strategy. Mesic populations also showed high plasticity in πtlp in response to water availability, indicating that osmotic adjustment to drought is an important component of this strategy. However, populations with mesophyllous leaves did not have higher maximum carbon assimilation rates under well-watered conditions. Furthermore, SLA was negatively associated with mass-based photosynthetic rates, contrary to expectations of the leaf economics spectrum, indicating that drought-resistance strategies are not

  20. Silvicultural options in ageing holm oak (Quercus ilex L. coppices in Gargano: results after 14 growing seasons

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    Scopigno D

    2008-12-01

    Full Text Available In the frame of a long-term research program concerning management of ageing holm oak coppices, results available after 14 growing seasons are reported in present paper. Experimental treatments include: A 50 standards per hectare, all of the same age; B 250 standards per hectare, all of the same age; C 140 standards per hectare, with two different ages; D conversion to high forest; E natural evolution (control. A total of 15 permanent plots were established (5 treatments x 3 replicates per treatment and the experimental design used is that of randomised blocks. Based on observations concerning seedlings and shoots development and standards growth and competitive effects, the following preliminary results may be highlighted: i recovering the traditional coppicing system with few standards per hectare represents a valid option from both ecological and shoots growth point of view; the stools, with few standards per hectare, showed a larger number of sprouts, provided with a higher average height and larger diameters; ii uneven-aged standards represent a good alternative form the points of view of both landscape impact immediately after felling operations and stand resistance to climatic damages; iii a good alternative is to apply conversion treatments to high forest, whenever their site quality allows these operations.

  1. Human contribution to trace elements in urban areas as measured in holm oak (Quercus ilex L.) bark.

    Science.gov (United States)

    Minganti, Vincenzo; Drava, Giuliana; Giordani, Paolo; Malaspina, Paola; Modenesi, Paolo

    2016-06-01

    The effect of human activities on the presence of trace elements in the atmosphere was evaluated by analyzing samples of holm oak bark, collected in Italy in a large city, in a small town, and in a reference area, scarcely inhabited. In all cases, point sources of pollution were excluded (e.g., industries and incinerators). The concentrations of As, Cd, Co, Cu, Fe, Mn, Ni, Pb, V, and Zn were measured using inductively coupled plasma optical emission spectrometry (ICP-OES). The element concentrations in the small town are not different from the reference area, except for Pb and Cu, while the samples collected in the large city show higher concentrations of Co, Cu, Fe, Ni, Pb, V, and Zn with respect to the rural area. In particular, the Pb levels in the large city are approximately 16 times higher than in the reference site, and five times higher than in the small town. Most element concentrations are correlated in the large city, while in the reference site, only a few significant correlations between elements were found. Even in the absence of specific sources of pollution, populations living in big cities are exposed to higher concentrations of trace elements than those living in rural environments or in small urban centers.

  2. Habitat Fragmentation can Modulate Drought Effects on the Plant-soil-microbial System in Mediterranean Holm Oak (Quercus ilex) Forests.

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    Flores-Rentería, Dulce; Curiel Yuste, Jorge; Rincón, Ana; Brearley, Francis Q; García-Gil, Juan Carlos; Valladares, Fernando

    2015-05-01

    Ecological transformations derived from habitat fragmentation have led to increased threats to above-ground biodiversity. However, the impacts of forest fragmentation on soils and their microbial communities are not well understood. We examined the effects of contrasting fragment sizes on the structure and functioning of soil microbial communities from holm oak forest patches in two bioclimatically different regions of Spain. We used a microcosm approach to simulate the annual summer drought cycle and first autumn rainfall (rewetting), evaluating the functional response of a plant-soil-microbial system. Forest fragment size had a significant effect on physicochemical characteristics and microbial functioning of soils, although the diversity and structure of microbial communities were not affected. The response of our plant-soil-microbial systems to drought was strongly modulated by the bioclimatic conditions and the fragment size from where the soils were obtained. Decreasing fragment size modulated the effects of drought by improving local environmental conditions with higher water and nutrient availability. However, this modulation was stronger for plant-soil-microbial systems built with soils from the northern region (colder and wetter) than for those built with soils from the southern region (warmer and drier) suggesting that the responsiveness of the soil-plant-microbial system to habitat fragmentation was strongly dependent on both the physicochemical characteristics of soils and the historical adaptation of soil microbial communities to specific bioclimatic conditions. This interaction challenges our understanding of future global change scenarios in Mediterranean ecosystems involving drier conditions and increased frequency of forest fragmentation.

  3. Effects of common oak (Quercus robur L. defolition on the soil properties of an oak forest in Western Plain of Romania

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    Aurelia Oneț

    2016-06-01

    Full Text Available This study was conducted to evaluate the variability of the chemical properties of the soil of an oak forest affected by defoliation and the corresponding microbial abundance. Soil samples were collected from a control zone (zone 1 without outbreaks of defoliating insects and from a sample zone (zone 2 where the trees were affected by Lymantria dispar L. defoliation. The research was conducted to determine the changed conditions for soil microorganisms produced as a consequence of defoliation. The results indicated, by means of analysis of variance (two-way ANOVA, P = 0.05, statistically significant differences (P < 0.0001 with respect to soil hydrolytic acidity, pH, ammonium nitrogen, heterotrophic bacteria, nitrogen fixing bacteria from genus Azotobacter and fungi. The data revealed a low number of heterotrophic bacteria and low pH values in samples taken from the area affected by defoliation. Soils under stands of defoliated trees showed higher values with respect to soil acidity, ammonium nitrogen, fungi and nitrogen fixing bacteria Azotobacter. Moreover, the soil moisture, nitrate nitrogen, organic matter content, organic carbon, the number of heterotrophic bacteria and the number of bacteria from genus Azotobacter exhibited statistically significant seasonal differences between the two zones studied. The correlations between the tested parameters showed that soil parameters such as moisture content, soil acidity, pH, organic matter content, organic carbon, total nitrogen and nitrate nitrogen are important factors influencing the soil populations of aerobic mesophilic heterotrophic bacteria, fungi and nitrogen fixing bacteria in the studied forest ecosystem.

  4. Drought Effects on Physiology and Biochemistry of Pedunculate Oak (Quercus robur L. and Hornbeam (Carpinus betulus L. Saplings Grown in Urban Area of Novi Sad, Serbia

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    Srđan Stojnić

    2016-06-01

    Full Text Available Background and Purpose: Water stress is one of the major problems for urban trees. It affects a wide range of plant responses, from changes at the cellular level to the reduction in growth rates. Irrigation of trees in urban areas may provide numerous benefits important for increasing tree vitality to withstand other stresses that might occur. The aim of this study was to compare drought effects on some physiological and biochemical performances of Pedunculate oak (Quercus robur L. and Hornbeam (Carpinus betulus L. saplings grown in the urban area. Materials and Methods: The study was conducted during August 2012 at the Boulevard of Europe (Novi Sad, Republic of Serbia. Measurements were carried out on saplings grown in the part of the boulevard with drip irrigation system installed (Site 1 and on the saplings cultivated in the part without any irrigation system (Site 2. Results: Soil moisture content was significantly higher at Site 1 with approximately 57.2%, compared to 18.7% at Site 2. The results showed that irrigated saplings were characterized by significantly higher stomatal conductance in Q. robur and C. betulus. Similarly, the content of free proline, FRAP units and the amount of malonyldialdehyde showed increased values in trees subjected to soil water deficit. In contrast, net photosynthesis, chlorophyll and carotenoid contents did not differ notably in irrigated and non-irrigated Q. robur and C. betulus trees. Conclusions: Water stress significantly affected stomatal conductance and some biochemical properties of Q. robur and C. betulus saplings cultivated at the non-irrigated site. The results showed that the implementation of drip irrigation system in urban landscape is an important tool in the prevention of drought stress effects on the physiological processes of plants.

  5. Phylogeny and biogeography of the American live oaks (Quercus subsection Virentes): a genomic and population genetics approach.

    Science.gov (United States)

    Cavender-Bares, Jeannine; González-Rodríguez, Antonio; Eaton, Deren A R; Hipp, Andrew A L; Beulke, Anne; Manos, Paul S

    2015-07-01

    The nature and timing of evolution of niche differentiation among closely related species remains an important question in ecology and evolution. The American live oak clade, Virentes, which spans the unglaciated temperate and tropical regions of North America and Mesoamerica, provides an instructive system in which to examine speciation and niche evolution. We generated a fossil-calibrated phylogeny of Virentes using RADseq data to estimate divergence times and used nuclear microsatellites, chloroplast sequences and an intron region of nitrate reductase (NIA-i3) to examine genetic diversity within species, rates of gene flow among species and ancestral population size of disjunct sister species. Transitions in functional and morphological traits associated with ecological and climatic niche axes were examined across the phylogeny. We found the Virentes to be monophyletic with three subclades, including a southwest clade, a southeastern US clade and a Central American/Cuban clade. Despite high leaf morphological variation within species and transpecific chloroplast haplotypes, RADseq and nuclear SSR data showed genetic coherence of species. We estimated a crown date for Virentes of 11 Ma and implicated the formation of the Sea of Cortés in a speciation event ~5 Ma. Tree height at maturity, associated with fire tolerance, differs among the sympatric species, while freezing tolerance appears to have diverged repeatedly across the tropical-temperate divide. Sympatric species thus show evidence of ecological niche differentiation but share climatic niches, while allopatric and parapatric species conserve ecological niches, but diverge in climatic niches. The mode of speciation and/or degree of co-occurrence may thus influence which niche axis plants diverge along. © 2015 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  6. Do chestnut, northern red, and white oak germinant seedlings respond similarly to light treatments? Growth and biomass

    Science.gov (United States)

    Joanne Rebbeck; Kurt Gottschalk; Amy. Scherzer

    2011-01-01

    Northern red oak (Quercus rubra L.) seedling growth has been extensively studied. White oak (Quercus alba L.) and chestnut oak (Quercus prinus L.), however, are far less investigated despite their importance among upland oak species in eastern North American forests. We characterized white and chestnut oak...

  7. Repeated summer drought and re-watering during the first growing year of oak (Quercus petraea delay autumn senescence and bud burst in the following spring

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    Kristine Vander Mijnsbrugge

    2016-03-01

    Full Text Available Climate change predicts harsher summer droughts for mid-latitudes in Europe. To enhance our understanding of the putative impacts on forest regeneration, we studied the response of oak seedlings (Quercus petraea to water deficit. Potted seedlings originating from three locally sourced provenances were subjected to two successive drought periods during the first growing season each followed by a plentiful re-watering. Here we describe survival and phenological responses after the second drought treatment, applying general linear mixed modelling. From the 441 drought treated seedlings 189 subsisted with higher chances of survival among smaller plants and among single plants per pot compared to doubles. Remarkably, survival was independent of the provenance, although relatively more plants had died off in two provenances compared to the third one with mean plant height being higher in one provenance and standard deviation of plant height being higher in the other. Timing of leaf senescence was clearly delayed after the severe drought treatment followed by re-watering, with two seedlings per pot showing a lesser retardation compared to single plants. This delay can be interpreted as a compensation time in which plants recover before entering the subsequent developmental process of leaf senescence, although it renders seedlings more vulnerable to early autumn frosts because of the delayed hardening of the shoots. Onset of bud flush in the subsequent spring still showed a significant but small delay in the drought treated group, independent of the number of seedlings per pot, and can be considered as an after effect of the delayed senescence. In both phenological models significant differences among the three provenances were detected independent from the treatment. The only provenance that is believed to be local of origin, displayed the earliest leaf senescence and the latest flushing, suggesting an adaptation to the local maritime climate. This

  8. Regeneration of red oak, quercus rubra l., using shelterwood systems: Ecophysiology, silviculture and management recommendations. Forest research information paper No. 126

    Energy Technology Data Exchange (ETDEWEB)

    Dey, D.C.; Parker, W.C.

    1996-11-01

    The purpose of this report is to review the scientific literature on red oak biology and silviculture as it pertains to the use of shelterwood systems in oak regeneration and management. Sections of the report describe oak ecophysiology and succession; growth characteristics; environmental requirements (light, water, nutrients, temperature) and response to stress (pests, competition); and oak regeneration ecology (acorn production and dispersal, seeding and germination requirements, artificial regeneration). The final section reviews oak management by shelterwood systems, including prescriptions for residual overstory, control of understory vegetation, stocking targets, and final overstory removal.

  9. A review of oak wilt management: a summary of treatment options and their efficacy

    Science.gov (United States)

    Karrie A. Koch; Gina L. Quiram; Robert C. Venette

    2010-01-01

    Oak wilt, caused by the invasive fungal pathogen Ceratocystis fagacearum (Bretz) Hunt, is a serious and fatal disease of oaks, Quercus spp., with red oaks (section Lobatae) generally being more susceptible than white oaks (section Quercus). Oak wilt was first recognized in North America in 1944...

  10. Effects of a low severity prescribed fire on water-soluble elements in ash from a cork oak (Quercus suber) forest located in the northeast of the Iberian Peninsula

    Science.gov (United States)

    Pereira, P.; beda, X.; Martin, D.; Mataix-Solera, J.; Guerrero, C.

    2011-01-01

    Wildfire is the major disturbance in Mediterranean forests. Prescribed fire can be an alternative to reduce the amount of fuel and hence decrease the wildfire risk. However the effects of prescribed fire must be studied, especially on ash properties, because ash is an important nutrient source for ecosystem recovery. The aim of this study is to determine the effects of a low severity prescribed fire on water-soluble elements in ash including pH, electrical conductivity (EC), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), silica (SiO2) and total sulphur (TS). A prescribed fire was conducted in a cork oak (Quercus suber) (Q.S) forest located in the northeast part of the Iberian Peninsula. Samples were collected from a flat plot of 40??70m mainly composed of Q.S and Quercus robur (Q.R) trees. In order to understand the effects of the prescribed fire on the soluble elements in ash, we conducted our data analysis on three data groups: all samples, only Q.S samples and only Q.R samples. All three sample groups exhibited a significant increase in pH, EC (pmanagement strategy. ?? 2010 Elsevier Inc.

  11. Photosynthetic Light Response of Bottomland Oak Seedlings Raised Under Partial Sunlight

    Science.gov (United States)

    Emile S. Gardiner

    2002-01-01

    Seedlings of cherrybark oak (Quercus pagoda Rafinesque), Nuttall oak (Quercus nuttallii Palmer) and overcup oak (Quercus lyrata Walter) were grown under two light levels, partial (20 percent) or full sunlight, to study physiological acclimation of leaves to low light availability. Shifts in leaf morphology were...

  12. VARIABILIDAD GENÉTICA DEL ROBLE COMÚN (Quercus humboldtii BONPL. EN LA REGIÓN DEL MACIZO COLOMBIANO GENETIC VARIABILITY OF COMMON OAK (Quercus humboldtii BONPL. IN THE MACIZO COLOMBIANO REGION VARIABILIDADE GENÉTICA DO ROBLE COMUM (Quercus humboldtii BONPL. NA REGIÃO DO MACIZO COLOMBIANO

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    GISELA MABEL PAZ P.

    2012-12-01

    estruturação genética entre as populações, e para manter e conservar o germoplasma recomenda-se conservar uma unidade panmítica, o qual requer a geração de corredores biológicos ou pelo menos para manter a atual diferenciação, precisa-se de planos de conservação de áreas naturais locais.Genetics impacts of fragmentation in populations depend, among other factors, of gene flow. With a restricted gene flow, fragmentation increases the probability of homozygosity and the loss of genetic diversity. These populations involve some species such as Quercus humboldtii (oak. To measure the levels of genetic diversity in 120 samples from 4 different populations in the Colombian Andean region (Macizo Colombiano, six primers of RAPDs markers were used. A total of 123 loci were obtained in all the populations, 122 of them were found to be polimorphic. The genetic diversity was of 0.4583 and the statistic value of genetic structure (GST was of 0.1616 with a genetic flow value of 2.58. Based on the results, it was underlined that there is a level of genetic structuration among the populations and for its sustenance and preservation of germplasm, it is reccomended: if the objective is to keep a panmictic unit, it is required to generate biologic corridors; but if it is required to maintain the current differentiation it wont be necessary the creation of these corridors but the creation of plans of local reforestation.

  13. Phylogeny and biogeography of East Asian evergreen oaks (Quercus section Cyclobalanopsis; Fagaceae): Insights into the Cenozoic history of evergreen broad-leaved forests in subtropical Asia.

    Science.gov (United States)

    Deng, Min; Jiang, Xiao-Long; Hipp, Andrew L; Manos, Paul S; Hahn, Marlene

    2018-02-01

    The evolutionary history of Quercus section Cyclobalanopsis, a dominant lineage in East Asian evergreen broadleaved forests (EBLFs), has not been comprehensively studied using molecular tools. In this study, we reconstruct the first comprehensive phylogeny of this lineage using a genomic approach (restriction-site associated DNA sequencing, RAD-seq), sampling 35 of the ca. 90 species currently recognized, representing all main morphological groups of section Cyclobalanopsis. In addition, 10 other species of Quercus and two outgroups were also sampled. Divergence times were estimated using a relaxed clock model and two fossil calibrations. Ancestral areas and dispersal routes were inferred using statistical dispersal-vicariance analysis and the dispersal-extinction-cladogenesis (DEC) model. The phylogeny of Quercus section Cyclobalanopsis demonstrates the section to be monophyletic, comprising two main lineages and six subclades that are well supported by anatomical traits. Biogeographical reconstructions indicate that the wide northern hemisphere distribution of Quercus was disrupted in the Late Eocene, leading to the main extant groups at about 33 Ma. The earliest divergences in section Cyclobalanopsis correspond to the phased uplift of the Himalayas and lateral extrusion of Indochina at the transition of the Oligocene and Miocene, where the highest rate of diversification occurred in the late Miocene. Dispersal from Sino-Himalaya and the Palaeotropics to Sino-Japan in the Miocene was facilitated by the increased intensity of East Asian summer monsoons and by the Middle Miocene Climatic Optimum. Our results highlight the importance of climatic changes and Indo-Eurasian collision-induced tectonic activities from the Neogene onward to the spatial-temporal diversification patterns of Asian EBLF lineages. Copyright © 2017. Published by Elsevier Inc.

  14. Do chestnut, northern red, and white oak germinant seedlings respond similary to light treatments? II. Gas exchange and chlorophyll responses

    Science.gov (United States)

    Joanne Rebbeck; Amy Scherzer; Kurt. Gottschalk

    2012-01-01

    Understanding differences in physiological and growth strategies in low-light environments among upland oak species may help managers address the challenges of oaks' poor regeneration. Gas exchange and chlorophyll content were measured for northern red oak (Quercus rubra L.), chestnut oak (Quercus prinus L.), and white oak (...

  15. Sudden oak death in California: what is the potential?

    Science.gov (United States)

    Tara M. Barrett; Demetrios Gatziolis; Jeremy S. Fried; Karen L. Waddell

    2006-01-01

    Sudden oak death, a disease associated with the pathogen Phytophthora ramorum, has a large number of shrub and tree host species. Three of the tree species must susceptible to mortality from the disease, California black oak (Quercus kelloggii), coast live oak (Quercus agrifolia), and tanoak (...

  16. 21 CFR 872.3240 - Dental bur.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental bur. 872.3240 Section 872.3240 Food and... DENTAL DEVICES Prosthetic Devices § 872.3240 Dental bur. (a) Identification. A dental bur is a rotary..., such as teeth or bone. It is also intended to cut hard metals, plastics, porcelains, and similar...

  17. Corrigendum: Batos B, Orlović S, Miletić Z, Rakonjac Lj, Miljković D.: Population variability and comparative analysis of macroelement concentrations in pedunculate oak (Quercus robur L. leaves and surrounding soils. Arch biol sci. 2014;66(4: 1345-55, DOI: 10.2298/ABS1404345B

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    Editorial

    2015-01-01

    Full Text Available The Editor-in-Chief has been informed that the results in Table 1 and in Table 2 presented in the article: Population variability and comparative analysis of macroelement concentrations in pedunculate oak (Quercus robur L. Leaves and surrounding soils published in the Archives of Biological Sciences in 2014, Vol. 66, Issue 4 partially overlap with the results in Tables 1, 2, 3a and 3b, published in the article Batos B, Miletić Z, Orlović S, Miljković D. Variability of nutritive macroelements in pedunculate oak (Quercus robur L. leaves in Serbia. Genetika. 2010;42(3:435-53, DOI: 10.2298/GENSR1003435B without proper cross-referencing. This claim is correct and we are reporting this overlap in order to provide appropriate cross-referencing to the earlier work. Link to the corrected article 10.2298/ABS1404345B

  18. Assessing wood quality of borer-infested red oak logs with a resonance acoustic technique

    Science.gov (United States)

    Xiping Wang; Henry E. Stelzer; Jan Wiedenbeck; Patricia K. Lebow; Robert J. Ross

    2009-01-01

    Large numbers of black oak (Quercus velutina Lam.) and scarlet oak (Quercus coccinea Muenchh.) trees are declining and dying in the Missouri Ozark forest as a result of oak decline. Red oak borer-infested trees produce low-grade logs that become extremely difficult to merchandize as the level of insect attack increases. The objective of this study was to investigate...

  19. [Effects of fire recurrence on fire behaviour in cork oak woodlands (Quercus suber L.) and Mediterranean shrublands over the last fifty years].

    Science.gov (United States)

    Schaffhauser, Alice; Pimont, François; Curt, Thomas; Cassagne, Nathalie; Dupuy, Jean-Luc; Tatoni, Thierry

    2015-12-01

    Past fire recurrence impacts the vegetation structure, and it is consequently hypothesized to alter its future fire behaviour. We examined the fire behaviour in shrubland-forest mosaics of southeastern France, which were organized along a range of fire frequency (0 to 3-4 fires along the past 50 years) and had different time intervals between fires. The mosaic was dominated by Quercus suber L. and Erica-Cistus shrubland communities. We described the vegetation structure through measurements of tree height, base of tree crown or shrub layer, mean diameter, cover, plant water content and bulk density. We used the physical model Firetec to simulate the fire behaviour. Fire intensity, fire spread, plant water content and biomass loss varied significantly according to fire recurrence and vegetation structure, mainly linked to the time since the last fire, then the number of fires. These results confirm that past fire recurrence affects future fire behaviour, with multi-layered vegetation (particularly high shrublands) producing more intense fires, contrary to submature Quercus woodlands that have not burnt since 1959 and that are unlikely to reburn. Further simulations, with more vegetation scenes according to shrub and canopy covers, will complete this study in order to discuss the fire propagation risk in heterogeneous vegetation, particularly in the Mediterranean area, with a view to a local management of these ecosystems. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  20. Risk analysis and guidelines for harvest activities in wisconsin oak timberlands to minimize oak wilt threat

    Science.gov (United States)

    Jennifer Juzwik; Jane Cummings-Carlson; Kyoko Scanlon

    2010-01-01

    Oaks (Quercus spp.) are an important species group in the forests of Wisconsin. The State’s timberland typed as oak-hickory forest was estimated at 2.9 million acres in 1996. Growing stock volume for red oak was estimated at 2.4 billion cubic feet, whereas select white oak volume was estimated to be 927 million cubic feet. Oak wilt, the oak disease...

  1. Response of Holm oak (Quercus ilex subsp. ballota) and mastic shrub (Pistacia lentiscus L.) seedlings to high concentrations of Cd and Tl in the rhizosphere.

    Science.gov (United States)

    Domínguez, María T; Marañón, Teodoro; Murillo, José Manuel; Redondo-Gómez, Susana

    2011-05-01

    The impairment of root growth and photosynthetical functioning are the main impacts of trace elements on woody plant seedlings. In this work, we assessed the response of Holm oak (Quercusilex subsp. ballota) and mastic shrub (Pistacia lentiscus) seedlings to high concentrations of Cd and Tl in the rhizosphere. These are non-essential trace elements, with a potential high mobility in the soil-plant system. Seedlings of these species are frequently used in the afforestation of degraded soils in mining areas. Plants were exposed to different levels of Cd (20, 80 and 200 mg L(-1)) and Tl (2, 10 and 20 mg L(-1)) in a sand culture. Biomass allocation, growth rates, chlorophyll fluorescence and gas exchange were studied. Both metals affected root biomass. Cadmium produced an increase in the root mass ratio and a decrease in the specific leaf area of the plants in oak seedlings, while Tl did not provoke such response. Mastic plants were more sensitive to Tl and Cd than oak plants. Between elements, Tl provoked more severe toxic effects in the plants, affecting the antennae complexes and reaction centers of the photosystem II. Both elements decreased net assimilation rates (down to a 20% of the control plants) and stomatal conductance (5-10% of the values for the control plants). Cadmium was highly retained in the roots of both species, while Tl was highly translocated into the leaves. In general, Holm oak showed a higher tolerance for Cd than for Tl, and a higher resistance to both metals than mastic shrub, due to a high capacity for Cd retention at the root level. However, such accumulation in roots may induce water stress in the seedling exposed to Cd. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Pollen gene flow, male reproductive success, and genetic correlations among offspring in a northern red oak (Quercus rubra L.) seed orchard.

    Science.gov (United States)

    Alexander, Lisa; Woeste, Keith

    2017-01-01

    Northern red oak is a high-value hardwood used for lumber, furniture and veneer. Intensively managed northern red oak seed orchards are required to obtain genetic gain for trait improvement. Data from conifer seed orchards and natural and managed stands of hardwood trees have shed light on the distance over which pollen can move, and underscore the need for managerial attention to seed orchard design, placement, and maintenance. We used eleven microsatellite markers to investigate pollen gene flow, female mate choice, and male reproductive success in a clonal seed orchard of northern red oak based on paternity analysis of seed orchard offspring in progeny tests. Nearly all (93%) offspring were sired by a male parent within the seed orchard. The mean number of male parents per year was 69.5, or 47.6% of all clones in the seed orchard. Female clones in the early phenology group had more offspring sired from extra-orchard pollen (13%) than clones in the intermediate (5%) and late (1%) phenology groups. Distance was the largest influence on pollination success, and pollination occurred most often by male trees in the same subline as the maternal tree. Males in the early phenology group sired more offspring overall in the progeny pool and more offspring per mother tree than males in the intermediate or late phenology groups. Average genetic correlations among all OP progeny ranged between 0.2557 and 0.3529 with a mean of 0.28±0.01. The importance of progeny test genotyping for northern red oak improvement likely is increasing with the demand for improved varieties. The current study demonstrated the feasibility of post hoc assembly of full-sib families for genetic analysis.

  3. Pollen gene flow, male reproductive success, and genetic correlations among offspring in a northern red oak (Quercus rubra L. seed orchard.

    Directory of Open Access Journals (Sweden)

    Lisa Alexander

    Full Text Available Northern red oak is a high-value hardwood used for lumber, furniture and veneer. Intensively managed northern red oak seed orchards are required to obtain genetic gain for trait improvement. Data from conifer seed orchards and natural and managed stands of hardwood trees have shed light on the distance over which pollen can move, and underscore the need for managerial attention to seed orchard design, placement, and maintenance. We used eleven microsatellite markers to investigate pollen gene flow, female mate choice, and male reproductive success in a clonal seed orchard of northern red oak based on paternity analysis of seed orchard offspring in progeny tests. Nearly all (93% offspring were sired by a male parent within the seed orchard. The mean number of male parents per year was 69.5, or 47.6% of all clones in the seed orchard. Female clones in the early phenology group had more offspring sired from extra-orchard pollen (13% than clones in the intermediate (5% and late (1% phenology groups. Distance was the largest influence on pollination success, and pollination occurred most often by male trees in the same subline as the maternal tree. Males in the early phenology group sired more offspring overall in the progeny pool and more offspring per mother tree than males in the intermediate or late phenology groups. Average genetic correlations among all OP progeny ranged between 0.2557 and 0.3529 with a mean of 0.28±0.01. The importance of progeny test genotyping for northern red oak improvement likely is increasing with the demand for improved varieties. The current study demonstrated the feasibility of post hoc assembly of full-sib families for genetic analysis.

  4. Identification of Quercus agrifolia (coast live oak resistant to the invasive pathogen Phytophthora ramorum in native stands using Fourier-transform infrared (FT-IR spectroscopy

    Directory of Open Access Journals (Sweden)

    Anna Olivia Conrad

    2014-10-01

    Full Text Available Over the last two decades coast live oak (CLO dominance in many California coastal ecosystems has been threatened by the alien invasive pathogen Phytophthora ramorum, the causal agent of sudden oak death. In spite of high infection and mortality rates in some areas, the presence of apparently resistant trees has been observed, including trees that become infected but recover over time. However, identifying resistant trees based on recovery alone can take many years. The objective of this study was to determine if Fourier-transform infrared (FT-IR spectroscopy, a chemical fingerprinting technique, can be used to identify CLO resistant to P. ramorum prior to infection. Soft independent modeling of class analogy identified spectral regions that differed between resistant and susceptible trees. Regions most useful for discrimination were associated with carbonyl group vibrations. Additionally, concentrations of two putative phenolic biomarkers of resistance were predicted using partial least squares regression; > 99% of the variation was explained by this analysis. This study demonstrates that chemical fingerprinting can be used to identify resistance in a natural population of forest trees prior to infection with a pathogen. FT-IR spectroscopy may be a useful approach for managing forests impacted by sudden oak death, as well as in other situations where emerging or existing forest pests and diseases are of concern.

  5. Tree Species Richness and Stand Productivity in Low-Density Cluster Plantings with Oaks (Quercus robur L. and Q. petraea (Mattuschka Liebl.

    Directory of Open Access Journals (Sweden)

    Christian Kuehne

    2013-08-01

    Full Text Available Low density plantings complemented by natural regeneration is an increasingly common reforestation technique to ensure growth of a sufficient number of trees from desired species while maintaining natural processes such as succession. One such form of low density planting that aims at lowering establishment costs—oak clusters—has been developed as an alternative to row planting since the 1980s in central Europe. However, whether cluster planting provides higher species richness and productivity than high density row planting has not previously been analyzed. Here, we compare tree species richness and productivity (measured as stand basal area between oak cluster plantings and conventional row planting in young (10–26 years old forest stands at seven study sites in Germany. Tree species richness was significantly higher in cluster plantings than in row plantings, whereas total basal areas were comparable. Naturally regenerated trees contributed on average to 43% of total stand basal area in cluster plantings, which was significantly higher than in row plantings. Total stand basal area in cluster planting was significantly related to the density of naturally regenerated trees. In turn, tree species diversity, density and basal area of naturally regenerated trees were increased with the size of unplanted area between clusters. Our results demonstrate that the admixture of naturally regenerated, early and mid-successional tree species compensates for a possible loss in productivity from planting fewer oaks. Low density cluster plantings can offer significant environmental benefits, at least for the first few decades of stand development, without compromising productivity.

  6. The epidemiology of sudden oak death in Oregon forests

    Science.gov (United States)

    Ebba K. Peterson

    2011-01-01

    The phytopathogen Phytophthora ramorum (Werres, DeCock & Man in't Veld), causal agent of Sudden Oak Death (SOD) of oaks (Quercus spp.) and tanoaks (Notholithocarpus densiflorus syn. Lithocarpus densiflorus...

  7. LIDAR-based estimation of leaf area index on Holm oak [Quercus ilex L. subsp. ballota (Desf.) Samp.] trees; Aplicacion de imagenes LIDAR para la estimacion de indices de superficie foliar (LAI) en encinas [Quercus ilex L. subsp. Ballota (Desf.) Samp.

    Energy Technology Data Exchange (ETDEWEB)

    Navarro Cerrillo, R. M.; Sanchez de la Orden, M.; Gomez Bonilla, J.; Garcia-Ferrer, A.; Hernandez Clemente, R.; Lanjeri, S.

    2010-07-01

    The aim of this paper was to estimate Leaf Area Index (LAI) of Quercus ilex by calculating the laser-intercepted rate through the forest canopy using LiDAR data. LAI was measured in 40 trees with a hemispheric camera (NIKON Coolpix 4500) and coincided with the acquisition of LIDAR data. The LiDAR-derived LAILIDAR was then estimated by applying a value of the inverse of the coefficient of extinction of 1/K 1.48. The in-field LAI values varied between 1.01 m{sup 2} m{sup -}2 and 1.61 m{sup 2} m{sup -}2. From a comparison of the LiDAR-derived to the field-derived LAI, the coefficients of the determination for the coefficient of extinction of 1.48 was R{sup 2} = 0.60 (RMSE = 0.16) for quadratic and R{sup 2} = 0.62 (RMSE = 0.21) for potential correlations. The change in accuracy was attributed to the density of leaves, the interference by stems, and the vertical number of branches in the forest stands. The LIDAR sensor technique gives a satisfactory result in the obtainment of leaf parameters in Holm oak trees, although its generalisation on field studies depends on its cost and suitability to be applied over large surfaces. (Author) 33 refs.

  8. Oaks belowground: mycorrhizas, truffles, and small mammals

    Science.gov (United States)

    Jonathan Frank; Seth Barry; Joseph Madden; Darlene Southworth

    2008-01-01

    Oaks depend on hidden diversity belowground. Oregon white oaks (Quercus garryana) form ectomycorrhizas with more than 40 species of fungi at a 25-ha site. Several of the most common oak mycorrhizal fungi form hypogeous fruiting bodies or truffles in the upper layer of mineral soil. We collected 18 species of truffles associated with Oregon white...

  9. Oak forests types of quercus humboldtii in the Guantiva-La Rusia-Iguaque corridor (Santander-Boyacá, Colombia: their conservation and sustainable use

    Directory of Open Access Journals (Sweden)

    Andrés Avella Muñoz

    2014-06-01

    Full Text Available Los bosques de robles en el corredor Guantiva-La Rusia-Iguaque corresponden a la formación mayor de Quercus humboldtii y Billia rosea, los cuales se clasificaron en una estructura jerárquica de siete tipos: Bosques de Q. humboldtii y Ocotea calophylla(franja altoandina > 3200 m, la gran formación de Q. humboldtii y Alchornea grandiflora, en la región andina con el robledal de Q. humboldtii - Blakea cuatrecasii y el de Q. humboldtii - Cyathea multiflora. En la parte baja de la región andina se diferenciaron los bosques de Q. humboldtii y Daphnopsis caracasana y los de Q. humboldtii y Pouteria baehniana. Los bosques de Virola macrocarpa y Q. humboldtii están presentes en la zona de vida sub-andina. Los robledales son considerados ecosistemas de alto valor cultural y social con dos prácticas principales de uso: como fuente de combustible y en el mantenimiento de las fincas (postes, estacas, madera. Según la caracterización florística y estructural, los bosques de Virola macrocarpa - Q. humboldtii, los de Q. humboldtii - Pouteria baehniana y los de Q. humboldtii - Daphnopsis caracasana podrían ser utilizados por la comunidad, bajo prescripciones técnicas. Los bosques de Q. humboldtii - Blakea cuatrecasii y de Q. humboldtii - Ocoteo calophylla no se deben usar, bajo ninguna condición, y deben ser objeto de un programa de protección estricta y restauración ecológica. Se deben implementar estrategias de conservación basadas en la generación de acuerdos de co-manejo entre las comunidades locales y las instituciones ambientales que faciliten su conservación bajo esquemas de uso sostenible.

  10. The effect of heat waves, elevated [CO2 ] and low soil water availability on northern red oak (Quercus rubra L.) seedlings.

    Science.gov (United States)

    Bauweraerts, Ingvar; Wertin, Timothy M; Ameye, Maarten; McGuire, Mary Anne; Teskey, Robert O; Steppe, Kathy

    2013-02-01

    The frequency and intensity of heat waves are predicted to increase. This study investigates whether heat waves would have the same impact as a constant increase in temperature with the same heat sum, and whether there would be any interactive effects of elevated [CO2 ] and soil moisture content. We grew Quercus rubra seedlings in treatment chambers maintained at either ambient or elevated [CO2 ] (380 or 700 μmol CO2 mol(-1) ) with temperature treatments of ambient, ambient +3 °C, moderate heat wave (+6 °C every other week) or severe heat wave (+12 °C every fourth week) temperatures. Averaged over a 4-week period, and the entire growing season, the three elevated temperature treatments had the same average temperature and heat sum. Half the seedlings were watered to a soil water content near field capacity, half to about 50% of this value. Foliar gas exchange measurements were performed morning and afternoon (9:00 and 15:00 hours) before, during and after an applied heat wave in August 2010. Biomass accumulation was measured after five heat wave cycles. Under ambient [CO2 ] and well-watered conditions, biomass accumulation was highest in the +3 °C treatment, intermediate in the +6 °C heat wave and lowest in the +12 °C heat wave treatment. This response was mitigated by elevated [CO2 ]. Low soil moisture significantly decreased net photosynthesis (Anet ) and biomass in all [CO2 ] and temperature treatments. The +12 °C heat wave reduced afternoon Anet by 23% in ambient [CO2 ]. Although this reduction was relatively greater under elevated [CO2 ], Anet values during this heat wave were still 34% higher than under ambient [CO2 ]. We concluded that heat waves affected biomass growth differently than the same amount of heat applied uniformly over the growing season, and that the plant response to heat waves also depends on [CO2 ] and soil moisture conditions. © 2012 Blackwell Publishing Ltd.

  11. Adsorption of Disperse Orange 30 dye onto activated carbon derived from Holm Oak (Quercus Ilex) acorns: A 3(k) factorial design and analysis.

    Science.gov (United States)

    Tezcan Un, Umran; Ates, Funda; Erginel, Nihal; Ozcan, Oznur; Oduncu, Emre

    2015-05-15

    In this study, samples of activated carbon were prepared from Holm Oak acorns by chemical activation with H3PO4, ZnCl2 and KOH as activating agents. The samples were characterized by SEM, BET, FTIR and elemental analysis, and were then evaluated for the removal of Disperse Orange 30 (DO30) dyes from aqueous solutions. A 3(k) factorial design was used to determine the interaction effects of carbonization temperature, pH, dosage of adsorbent and type of activating agent on the amount of dye removal. Also, level of effectiveness factors were determined by conducting regression models for maximum adsorption efficiency. Of all the samples, the sample generated using ZnCl2 as an activating agent showed a maximum dye removal efficiency of 93.5% at a carbonization temperature of 750 °C, a pH of 2 and an adsorbent dosage of 0.15 g/25 ml. The analysis shows that the adsorption process depends significantly on the type of activating agent used in the preparation of activated carbon. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Oak (Quercus frainetto Ten. Honeydew Honey—Approach to Screening of Volatile Organic Composition and Antioxidant Capacity (DPPH and FRAP Assay

    Directory of Open Access Journals (Sweden)

    Igor Jerković

    2010-05-01

    Full Text Available Two samples of oak honeydew honey were investigated. Headspace solid-phase microextraction (HS-SPME combined with GC and GC/MS enabled identification of the most volatile organic headspace compounds being dominated by terpenes(mainly cis- and trans-linalool oxides. The volatile and less-volatile organic composition of the samples was obtained by ultrasonic assisted extraction (USE with two solvents (1:2 (v/v pentane -diethyl ether mixture and dichloromethane followed by GC and GC/MS analysis. Shikimic pathway derivatives are of particular interest with respect to the botanical origin of honey and the most abundant was phenylacetic acid (up to 16.4%. Antiradical activity (DPPH assay of the honeydew samples was 4.5 and 5.1 mmol TEAC/kg. Ultrasonic solvent extracts showed several dozen times higher antiradical capacity in comparison to the honeydew. Antioxidant capacity (FRAP assay of honeydew samples was 4.8 and 16.1 mmol Fe2+/kg, while the solvent mixture extracts showed antioxidant activity of 374.5 and 955.9 Fe2+/kg, respectively, and the dichloromethane extracts 127.3 and 101.5 mmol Fe2+/kg.

  13. Effect of acorn moisture content at sowing on germination and seedling growth of white oak and northern red oak

    Science.gov (United States)

    Shi-Jean Susana Sung; Paul P. Kormanik; Catharine D. Cook; Stanley J. Zarnoch; Taryn L. Kormanik

    2006-01-01

    White oak (Quercus alba L.) and northern red oak (Q. rubra L.) acorns were collected locally or from seed orchards in October 2002. Mean acorn moisture content (MC) was 48 percent for white oak and 39 percent for northern red oak. These acorns were air dried to different MCs before being sown into nursery beds in early December...

  14. Biochemical, physiological and climatic influence on the emission of isoprenoides from Grey Poplar (Populus x canescens (Aiton) Sm.) and Holm Oak (Quercus ilex L.); Biochemische, physiologische und klimatische Einfluesse auf die Isoprenoidemission der Graupappel (Populus x canescens (Aiton) Sm.) und der Steineiche (Quercus ilex L.)

    Energy Technology Data Exchange (ETDEWEB)

    Mayrhofer, S.

    2007-05-15

    Because of their important role for the atmospheric chemistry, global daily and seasonal emission rates of isoprene and monoterpenes have to be estimated with accuracy. Therefore, detailed knowledge of biochemical and physiological processes within the plant metabolism has to be gathered. Afterwards the gained cognitions are used as information for process-based model calculations. The major scope of the work was therefore to enlarge basic knowledge of the regulation of isoprenoid emission, which is known to be dependent on several environmental factors, especially light and temperature. Measurements of diurnal isoprene emission have been performed in parallel on physiological, translational and transcriptional level on leaves of Grey Poplar (Populus x canescens), a strong isoprene emitting species. Additionally, examinations of diurnal monoterpene emission in connection to physiologic and enzymatic processes was conducted in leaves of Holm Oak (Quercus ilex), which emits a large spectrum of monoterpenes. Furthermore a hypothesis was tested, whether isoprene emission may serve the plant as antioxidative protection mechanism in order to overcome oxidative stress. In main parts, the following results have been reached: 1. In the first part of this work, isolation of PcDXR (DXR of Grey Poplar) from a cDNA-Genbank and heterologous expression of the isolated gene was accomplished. 2. Daytime variation of physiological and biochemical parameters of the isoprene emission of Grey Poplar was measured twice on 2 following days in 2 years. All together, measurements have been performed on 8 representative plants. 3. Quantitative RT-PCR elucidated the gene expression pattern of PcDXR and PcISPS in parallel to diurnal gas exchange measurements. Gene expression of PcISPS showed distinct diurnal courses with maximum values on the late morning, whereas PcDXR transcript levels stayed consistent over the day. No short-term influence of PPFD and leaf temperature has been observed on

  15. Direct Effects of Carpophagous Insects on the Germination Ability and Early Abscission of Oak Acorns

    OpenAIRE

    Csóka, György; Hirka, Anikó

    2006-01-01

    Carpophagous insects play an important role in decreasing the viability of acorns in bothdirect and indirect ways. Therefore they significantly influence the reproductive potential of oaks. As adirect effect, their feeding on the embryo and on the cotyledons may prevent the germination of theacorn and on the other hand, their damage causes premature acorn abscission. During 3 years, 60acorn samples from five oak species (Turkey oakQuercus cerris, pedunculate oakQuercus robur,sessile oak...

  16. Assessing Methods to Protect Susceptible Oak and Tanoak Stands from Sudden Oak Death

    Science.gov (United States)

    Tedmund Swiecki; Elizabeth Bernhardt

    2010-01-01

    Landowners and managers have been seeking ways to protect susceptible oak (Quercus) species and tanoak (Lithocarpus densiflorus) from sudden oak death (SOD) caused by Phytophthora ramorum. Because disease epidemiology differs between tanoaks and susceptible oaks, we are testing different control strategies...

  17. Effects of Flood Duration and Depth on Germination of Cherrybark, Post, Southern, White and Willow Oak Acorns

    Science.gov (United States)

    Yanfei Guo; Michael G. Shelton; Eric Heitzman

    2002-01-01

    Effects of flood duration (0, 10, 20, and 30 days) and depth (10 and 100 centimeters below a water surface) on acorn germination were tested for two bottomland oaks (cherrybark oak [Quercus pagoda Raf.] and willow oak [Q. phellos L.]) and three upland oaks (post oak [Q. stellata Wang.], southern red oak [

  18. Insects that damage northern red oak acorns

    Science.gov (United States)

    Lester P. Gibson

    1982-01-01

    From 1961 to 1964 and in 1979, the insects found damaging acorns of northern red oak (Quercus rubra L.) in their relative order of abundance were: Curculio proboscideus F., C. sulcatulus (Casey), Melissopus latiferreanus (Wals.), C. nasicus (Say), C. orthorhynchus...

  19. The effect of seed size variation in Quercus pacifica on seedling establishment and growth

    Science.gov (United States)

    Mario B. Pesendorfer

    2015-01-01

    Quercus pacifica, the island scrub-oak, is the dominant species in oak chaparral on the three largest California Channel Islands. While the population on Santa Cruz Island has experienced a strong recovery, the populations on Santa Rosa and Santa Catalina islands are of conservation concern, and managers are actively restoring oak habitat by...

  20. A comparison of the survival and development of the seedlings of four upland oak species grown in four different understory light environments

    Science.gov (United States)

    Patrick Brose; Joanne Rebbeck

    2017-01-01

    Oak (Quercus spp.) research and management often focus on northern red oak (Quercus rubra) and assume that associated upland oaks have similar growth patterns. To test this premise, we measured the survival and development of four species of acorn-origin oak seedlings growing in four different levels of understory sunlight for...

  1. Why does Quercus suber species decline in Mediterranean areas?

    Directory of Open Access Journals (Sweden)

    Hae Naem Kim

    2017-09-01

    Full Text Available The cork oak (Quercus suber L. is a prevalent tree species in the Mediterranean climate zones of western Europe and north Africa with a quite narrow geographical range of distribution, as compared with the other Mediterranean evergreen oak species such as Quercus calliprinos (holly oak and Quercus ilex (holm oak. This species offers the ecological, economic and social importance, including their biodiversity and sustainable forest production in these areas. The increase of mean annual temperature and rainfall extremes during recent decades follows the trends predicted by present climate change models projecting a higher frequency of droughts and intense rain events in the Mediterranean climate areas. Nevertheless, various biotic and abiotic factors, including climate change (increased frequency and rigor of high temperature and drought and related physiological decline of trees, increases in the outbreaks of disease, and an excessive development of forest resources has been recognized as main factors to induce a cork oak forest decline. In general, sustainable cork oak forest management and proper agroforestry activity that can generate income for local people through local community participation would be the ways to prevent cork oak forest decline in northern Tunisia.

  2. Avian abundance and oak mistletoe survey data from the Willamette Valley, Oregon, 2013-2015

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset includes two spreadsheets: The "Avian_abundance_oak_mistletoe_bird_data" spreadsheet contains data regarding Oregon White Oak tree (Quercus garryana)...

  3. Acorn Production Characteristics of Southern Appalachian Oaks: A Simple Method to Predict Within-Year Crop Size

    Science.gov (United States)

    Cathryn H. Greenberg; Bernard R. Parresol

    2000-01-01

    We examined acorn production from 1993-97 by black oak (Quercus velutina Lam.), northern red oak (Q. rubra L.), scarlet oak (Q. coccinea Muenchh.), chestnut oak (Q. prinus L.), and white oak (Q. alba L.) in the Southern Appalichians to determine how frequency of acorn...

  4. Distributional record of oak gall wasp (Hymenoptera: Cynipidae ...

    African Journals Online (AJOL)

    Hymenoptera: Cynipidae) that occur on oak trees (Quercus spp.) and produce galls on a certain part of the host. In this survey, oak gall wasp species were collected from the oak forests of Pardanan, Mirabad, Nalas, Sardasht, Hamran and Dar-ghabr in ...

  5. Fire in Eastern North American Oak Ecosystems: Filling the Gaps

    Science.gov (United States)

    Julian (Morgan) Varner; Mary Arthur; Stacy Clark; Daniel C. Dey; Justin Hart; Callie Schweitzer

    2016-01-01

    This special issue of Fire Ecology is focused on the fire ecology of eastern USA oak (Quercus L.) forests, woodlands, and savannas. The papers were presented as part of the Fifth Fire in Eastern Oak Forests Conference in Tuscaloosa, Alabama, USA, in 2015. The topic of fire in eastern oak ecosystems is one that has received insufficient interest from the...

  6. Blue and Valley Oak Seedling Establishment on California's Hardwood Rangelands

    Science.gov (United States)

    Theodore E. Adams Jr.; Peter B. Sands; William H. Weitkamp; Neil K. McDougald

    1991-01-01

    Factors contributing to poor establishment of blue oak (Quercus douglasii) and valley oak (Q. lobata) in California oak-grassland savannas were studied in a series of acorn seeding experiments initiated in 1985. Exclusion of large herbivores permitted examination of herbaceous interference and small mammal and insect depredation....

  7. Managing California black oak for tribal ecocultural restoration

    Science.gov (United States)

    Jonathan W. Long; Ron W. Goode; Raymond J. Gutteriez; Jessica J. Lackey; M. Kat Anderson

    2017-01-01

    Many tribes in California and Oregon value California black oak (Quercus kelloggii) as a traditional source of food and other values. Over centuries or millennia, Native Americans learned that they could enhance production of desired resources by regularly igniting low-intensity surface fires in stands of black oak. Although black oak is likely to...

  8. Factors limiting recruitment in valley and coast live oak

    Science.gov (United States)

    Claudia M. Tyler; Bruce E. Mahall; Frank W. Davis; Michael Hall

    2002-01-01

    The Santa Barbara County Oak Restoration Program was initiated in 1994 to determine the major factors limiting recruitment of valley oak (Quercus lobata) and coast live oak (Q. agrifolia). At Sedgwick Reserve in Santa Barbara County, California, we have replicated large-scale planting experiments in four different years to...

  9. Bird communities of gambel oak: a descriptive analysis

    Science.gov (United States)

    Andreas Leidolf; Michael L. Wolfe; Rosemary L. Pendleton

    2000-01-01

    Gambel oak (Quercus gambelii Nutt.) covers 3.75 million hectares (9.3 million acres) of the western United States. This report synthesizes current knowledge on the composition, structure, and habitat relationships of gambel oak avian communities. It lists life history attributes of 183 bird species documented from gambel oak habitats of the western...

  10. Development, succession, and stand dynamics of upland oak forests in the Wisconsin Driftless Area: Implications for oak regeneration and management

    Science.gov (United States)

    Megan L. Buchanan; Kurt F. Kipfmueller; Anthony W. D' Amato

    2017-01-01

    Throughout the deciduous forests of the eastern United States, oak (Quercus) regeneration has declined in stands historically dominated by oak species. In the Wisconsin Driftless Area, the level of decline in oak regeneration is variable and influenced by stand structural development, historical disturbance regime, abiotic site characteristics, and...

  11. An ecologically based approach to oak silviculture: a synthesis of 50 years of oak ecosystem research in North America

    Science.gov (United States)

    Daniel C. Dey; Alejandro A. Royo; Patrick H. Brose; Todd F. Hutchinson; Martin A. Spetich; Scott H. Stoleson

    2010-01-01

    Oak (Quercus L.) is an abundant and widely distributed genus in eastern North America. A history of periodic fire, grazing, canopy disturbance and timber harvesting has favored oak's dominance. But, changes in this regime toward much less fire or complete fire suppression, and selective cutting are causing the successional replacement of oak....

  12. A meta-analysis of the fire-oak hypothesis: Does prescribed burning promote oak reproduction in eastern North America

    Science.gov (United States)

    Patrick H. Brose; Daniel C. Dey; Ross J. Phillips; Thomas A. Waldrop

    2013-01-01

    The fire-oak hypothesis asserts that the current lack of fire is a reason behind the widespread oak (Quercus spp.) regeneration difficulties of eastern North America, and use of prescribed burning can help solve this problem. We performed a meta-analysis on the data from 32 prescribed fire studies conducted in mixed-oak forests to test whether they...

  13. The Use of Soil Scarification to Enhance Oak Regeneration in a Mixed-Oak Bottomland Forest of Southern Illinois

    Science.gov (United States)

    John M. Lhotka; James J. Zaczek

    2002-01-01

    The purpose of the study was to investigate whether soil scarification following seed fall can be used to increase the density of oak regeneration in a mixed-oak stand. The study area was a 4.5-hectare stand dominated by cherrybark oak (Quercus pagoda Eli.). The understory had a high percent cover of poison ivy (Toxicodendron radicans...

  14. Cork oak woodlands patchiness

    DEFF Research Database (Denmark)

    Costa, Augusta; Madeira, Manuel; Plieninger, Tobias

    2014-01-01

    The cork oak (Quercus suber L.) woodlands of the agroforestry landscapes of Southwestern Iberia are undergoing drastic change due to severe natural and anthropogenic disturbances. These may eventually result in woodland loss or deforestation, the final step of an ongoing process of woodland...... woodlands exhibited similar trends of decreasing fractional canopy cover and decreasing number of larger patches. Patchiness rather than fractional canopy cover seems, however, to be potentially more useful as a signature of imminent oak woodlands deforestation, given that its contrast before and after...

  15. Shade, leaf growth, and crown development of Quercus rubra, Q. velutina, Prunus serotina, and Acer rubrum seedlings

    Science.gov (United States)

    Kurt W. Gottschalk

    1994-01-01

    The study was conducted in an open field to detennine the optimum irradiance for establishment and growth of two oak species and two major associated woody species. Half-sib seedlings of black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), northern red oak (Quercus rubra L.) and black oak (Q. velutina Lam.) were grown for two years under shade-clotht...

  16. Diagnosis and Management of Phytophthora ramorum canker in canyon live oak, an atypical bole canker host

    Science.gov (United States)

    Tedmund J. Swiecki; Elizabeth Bernhardt; Kamyar Aram; David Rizzo

    2013-01-01

    Diagnosis of sudden oak death (SOD) in tanoak (Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh) and susceptible red/black oak species (coast live oak, Quercus agrifolia Née; Shreve oak, Q. parvula Greene var. shrevei (C.H. Mull.) Nixon; California...

  17. Red oak decline and mortality by ecological land type in the Missouri ozarks

    Science.gov (United States)

    John M. Fan Kabrick; Stephen R. Shifley

    2007-01-01

    Oak decline, the precipitous mortality of mature oak trees, has been a chronic problem in xeric oak ecosystems and is reaching unprecedented levels in red oak group (Quercus section Lobatae) species in the Ozark Highlands. The high rates of mortality are leading to rapid changes in species composition, forest structure, and related changes in fire...

  18. Response of outplanted northern red oak seedlings under two silvicultural prescriptions in north Alabama

    Science.gov (United States)

    Callie Jo Schweitzer; Emile Gardiner; Stephanie Love; Tom Green

    2005-01-01

    The decision to artificially regenerate oak must be predicated on some basis. After completing an assessment of the potential to regenerate oak naturally, we decided our stands might benefit from supplemental oak plantings. The primary objective of this study was to couple outplanting of northern red oak (Quercus rubra L.) with applied silviculture...

  19. Modeling and mapping oak advance reproduction density using soil and site variables

    Science.gov (United States)

    John M. Kabrick; Jason L. Villwock; Daniel C. Dey; Tara L. Keyser; David R. Larsen

    2014-01-01

    Regenerating oaks (Quercus spp.) has remained a widespread and persistent problem throughout their natural range. Research shows that abundant oak advance reproduction is crucial for success. Although it is recognized that oak advance reproduction accumulation is inversely related to site quality, there has been little effort to model oak advance...

  20. Ecology and management of oak woodlands and savannas in the southwestern Borderlands Region

    Science.gov (United States)

    Gerald J. Gottfried; Peter F. Ffolliott

    2013-01-01

    Management of the Madrean oak woodlands and the less dense and ecologically different oak savannas must be based on sound ecological information. However, relatively little is known about the Madrean oak ecosystems in spite of the fact that they cover about 80,000 km2 in the southwestern United States and northern Mexico. Emory oak (Quercus emoryi), the dominant tree...

  1. Mycorrhizas on nursery and field seedlings of Quercus garryana

    Science.gov (United States)

    Dariene Southworth; Elizabeth M. Carrington; Jonathan L. Frank; Peter Gould; Connie A. Harrington; Warren D. Devine

    2009-01-01

    Oak woodland regeneration and restoration requires that seedlings develop mycorrhizas, yet the need for this mutualistic association is often overlooked. In this study, we asked whether Quercus garryana seedlings in nursery beds acquire mycorrhizas without artificial inoculation or access to a mycorrhizal network of other ectomycorrhizal hosts. We...

  2. Meadow vole-induced mortality of oak seedlings in a former agricultural field planting

    Science.gov (United States)

    Andrew B. Self; Andrew W. Ezell; Dennis Rowe; Emily B. Schultz; John D. Hodges

    2015-01-01

    Seedling mortality due to meadow vole herbivory is an often acknowledged but relatively unstudied aspect of hardwood afforestation. Vole-induced mortality is not typically a major item of concern in afforestation attempts. However, damage has been extreme in some plantings. A total of 4,320 bare-root Nuttall oak (Quercus texana Buckley), Shumard oak (Quercus shumardii...

  3. Responses of northern red oak seedlings to lime and deer exclosure fencing in Pennsylvania

    Science.gov (United States)

    Robert P. Long; Patrick H. Brose; Stephen B. Horsley

    2012-01-01

    In Pennsylvania, two hypotheses compete to explain the chronic oak (Quercus spp.) regeneration problem: excessive deer browsing and soil cation depletion. We tested these hypotheses by evaluating the effect of forest liming and deer exclosure fencing on northern red oak (Quercus rubra L.) seedling growth and nutrition in five...

  4. Pollen morphology of Quercus (subgenus Quercus, section Quercus in Iran and its systematic implication

    Directory of Open Access Journals (Sweden)

    Parisa Panahi

    2012-03-01

    Full Text Available For the first time, pollen morphology of 9 (4 spp. and 5 subspp. taxa representing lobed leaved oaks of Iran in the family of Fagaceae has been examined and illustrated using light microscopy and scanning electron microscopy of acetolysed material. Detailed pollen morphological characteristics are given for Quercus section. The pollen grains are single, isopolar, radially symmetrical, tricolpate, tricolporoidate or tricolporate. Pollens were studied to show all possible characteristics like shape, size, apertures, wall thickness, etc., with special reference to the specific features of each pollen type such as structural, sculptural and suprasculptural patterns. There is considerable variation in pollen morphology between taxa so that, three types of pollen shape, five types of structural pattern, two types of sculptural pattern, five types of suprasculptural pattern and three types of perfora distribution are defined. Furthermore, the relationship between pollen morphology and taxonomy is discussed. Overall, pollen characters are shown to be a useful and informative tool for assessing taxonomic position within Quercus section in Iran.

  5. Effect of phosphate treatments on sudden oak death in tanoak and Shreve's oak

    Science.gov (United States)

    Doug Schmidt; Matteo Garbelotto; Dave Chambers; Steve Tjosvold

    2006-01-01

    Field experiments were conducted to evaluate the effectiveness of phosphonate chemical treatments for control of sudden oak death in tanoak (Lithocarpus densiflorus) and Shreve's oak (Quercus parvula var. Shrevei). Native stands of mature trees were preventatively treated with Agrifos® systemic fungicide and...

  6. Comparison of oak and sugar maple distribution and regeneration in central Illinois upland oak forests

    Science.gov (United States)

    Peter J. Frey; Scott J. Meiners

    2014-01-01

    Changes in disturbance frequencies, habitat fragmentation, and other biotic pressures are allowing sugar maple (Acer saccharum) to displace oak (Quercus spp.) in the upland forest understory. The displacement of oaks by sugar maples represents a major management concern throughout the region. We collected seedling microhabitat data...

  7. Plastome data reveal multiple geographic origins of Quercus Group Ilex

    Directory of Open Access Journals (Sweden)

    Marco Cosimo Simeone

    2016-04-01

    Full Text Available Nucleotide sequences from the plastome are currently the main source for assessing taxonomic and phylogenetic relationships in flowering plants and their historical biogeography at all hierarchical levels. One major exception is the large and economically important genus Quercus (oaks. Whereas differentiation patterns of the nuclear genome are in agreement with morphology and the fossil record, diversity patterns in the plastome are at odds with established taxonomic and phylogenetic relationships. However, the extent and evolutionary implications of this incongruence has yet to be fully uncovered. The DNA sequence divergence of four Euro-Mediterranean Group Ilex oak species (Quercus ilex L., Q. coccifera L., Q. aucheri Jaub. & Spach., Q. alnifolia Poech. was explored at three chloroplast markers (rbcL, trnK/matK, trnH-psbA. Phylogenetic relationships were reconstructed including worldwide members of additional 55 species representing all Quercus subgeneric groups. Family and order sequence data were harvested from gene banks to better frame the observed divergence in larger taxonomic contexts. We found a strong geographic sorting in the focal group and the genus in general that is entirely decoupled from species boundaries. High plastid divergence in members of Quercus Group Ilex, including haplotypes shared with related, but long isolated oak lineages, point towards multiple geographic origins of this group of oaks. The results suggest that incomplete lineage sorting and repeated phases of asymmetrical introgression among ancestral lineages of Group Ilex and two other main Groups of Eurasian oaks (Cyclobalanopsis and Cerris caused this complex pattern. Comparison with the current phylogenetic synthesis also suggests an initial high- versus mid-latitude biogeographic split within Quercus. High plastome plasticity of Group Ilex reflects geographic area disruptions, possibly linked with high tectonic activity of past and modern distribution

  8. Plastome data reveal multiple geographic origins of Quercus Group Ilex.

    Science.gov (United States)

    Simeone, Marco Cosimo; Grimm, Guido W; Papini, Alessio; Vessella, Federico; Cardoni, Simone; Tordoni, Enrico; Piredda, Roberta; Franc, Alain; Denk, Thomas

    2016-01-01

    Nucleotide sequences from the plastome are currently the main source for assessing taxonomic and phylogenetic relationships in flowering plants and their historical biogeography at all hierarchical levels. One major exception is the large and economically important genus Quercus (oaks). Whereas differentiation patterns of the nuclear genome are in agreement with morphology and the fossil record, diversity patterns in the plastome are at odds with established taxonomic and phylogenetic relationships. However, the extent and evolutionary implications of this incongruence has yet to be fully uncovered. The DNA sequence divergence of four Euro-Mediterranean Group Ilex oak species (Quercus ilex L., Q. coccifera L., Q. aucheri Jaub. & Spach., Q. alnifolia Poech.) was explored at three chloroplast markers (rbcL, trnK/matK, trnH-psbA). Phylogenetic relationships were reconstructed including worldwide members of additional 55 species representing all Quercus subgeneric groups. Family and order sequence data were harvested from gene banks to better frame the observed divergence in larger taxonomic contexts. We found a strong geographic sorting in the focal group and the genus in general that is entirely decoupled from species boundaries. High plastid divergence in members of Quercus Group Ilex, including haplotypes shared with related, but long isolated oak lineages, point towards multiple geographic origins of this group of oaks. The results suggest that incomplete lineage sorting and repeated phases of asymmetrical introgression among ancestral lineages of Group Ilex and two other main Groups of Eurasian oaks (Cyclobalanopsis and Cerris) caused this complex pattern. Comparison with the current phylogenetic synthesis also suggests an initial high- versus mid-latitude biogeographic split within Quercus. High plastome plasticity of Group Ilex reflects geographic area disruptions, possibly linked with high tectonic activity of past and modern distribution ranges, that did not

  9. The transcription elongation factor Bur1-Bur2 interacts with replication protein A and maintains genome stability during replication stress

    DEFF Research Database (Denmark)

    Clausing, Emanuel; Mayer, Andreas; Chanarat, Sittinan

    2010-01-01

    Multiple DNA-associated processes such as DNA repair, replication, and recombination are crucial for the maintenance of genome integrity. Here, we show a novel interaction between the transcription elongation factor Bur1-Bur2 and replication protein A (RPA), the eukaryotic single-stranded DNA...... foci. Interestingly, the DNA damage sensitivity of an rfa1 mutant was suppressed by bur1 mutation, further underscoring a functional link between these two protein complexes. The transcription elongation factor Bur1-Bur2 interacts with RPA and maintains genome integrity during DNA replication stress....

  10. Effects of disking, bedding, and subsoiling on survival and growth of three oak species in central Mississippi

    Science.gov (United States)

    J. Paul Jeffreys; Emily B. Schultz; Thomas G. Matney; W. Cade Booth; Jason M. Morris

    2010-01-01

    A replicated split-plot design experiment to evaluate the effects of three site preparation methods (disking, bedding, and subsoiling plus bedding) on survival and growth of three oak species (cherrybark, Quercus pagoda Raf.; Shumard, Quercus shumardii Buckl.; and Nuttall, Quercus texana Buckl.) was established...

  11. Soil properties and understory herbaceous biomass in forests of three species of Quercus in Northeast Portugal

    Directory of Open Access Journals (Sweden)

    Marina Castro

    2014-12-01

    Full Text Available Aim of study: This paper aims to characterize some soil properties within the first 25 cm of the soil profile and the herbaceous biomass in Quercus forests, and the possible relationships between soil properties and understory standing biomass.Area of study: Three monoespecific Quercus forests (Q. suber L., Q. ilex subsp. rotundifolia Lam. and Q. pyrenaica Willd in NE Portugal.Material and methods: During 1999 and 2000 soil properties (pH-KCl, total soil nitrogen (N, soil organic carbon (SOC, C/N ratio, available phosphorus (P, and available potassium (K and herbaceous biomass production of three forest types: Quercus suber L., Quercus ilex subsp. rotundifolia Lam. and Quercus pyrenaica Willd were studied.Main results: The results showed a different pattern of soil fertility (N, SOC, P, K in Quercus forests in NE of Portugal. The C/N ratio and the herbaceous biomass confirmed this pattern. Research highlights: There is a pattern of Quercus sp. distribution that correlates with different soil characteristics by soil characteristics in NE Portugal. Q. pyrenaica ecosystems were found in more favoured areas (mesic conditions; Q. rotundifolia developed in nutrient-poor soils (oligotrophic conditions; and Q. suber were found in intermediate zones.Keywords: fertility; biomass; C/N ratio; cork oak; holm oak; pyrenean oak.

  12. Field test of foliar-spray herbicides to control mountain laurel in mature mixed-oak forests in western Maryland

    Science.gov (United States)

    Gary W. Miller; Patrick H. Brose; Jeffrey D. Kochenderfer; James N. Kochenderfer; Kurt W. Gottschalk; John R. Denning

    2016-01-01

    Successful oak (Quercus spp.) regeneration requires the presence of competitive sources of oak reproduction before parent oaks are harvested. Mountain laurel (Kalmia latifolia) in the understory of many Appalachian forests prevents new oak seedlings from receiving adequate sunlight to survive and grow into competitive size classes. This study examined the efficacy of...

  13. Effects of flood duration and season on germination of black, cherrybark, northern red, and water oak acorns

    Science.gov (United States)

    Yanfei Guo; Michael G. Shelton; Brian R. Lockhart

    1998-01-01

    Effects of flood duration (0, 10, 20, and 30 days) and season (winter and spring) on acorn germination were tested for two upland oaks [black and northern red oak (Quercus velutina Lam. and Q. rubra L.)] and two bottomland oaks [cherrybark and water oak (Q. pagoda Raf. and Q. nigra L.)]. Acorns...

  14. Spatial pattern of Quercus ilex and Quercus pubescens recruitment in Pinus halepensis dominated woodlands

    Energy Technology Data Exchange (ETDEWEB)

    Lookingbill, T.R. [Duke Univ., Durham, NC (United States). Nicholas School of the Environment; Zavala, M.A. [Princeton Univ., NJ (United States). Dept. of Ecology and Evolutionary Biology

    2000-08-01

    European Mediterranean landscapes have undergone changes in structure in recent years as a result of widespread agricultural land abandonment and cessation of silvicultural regimes. Studies concerning the regeneration dynamics of dominant forest species have become critical to the prediction of future landscape trends in these changing forest stands. Quercus ilex (holm oak) and Q. pubescens (downy oak) are considered to be the terminal point of secondary succession in extensive areas of the Mediterranean region. Recent studies, however, have suggested the existence of recruitment bottlenecks in oak genet populations as a result of current management regimes. In this study, we present evidence of the successful establishment of Q. ilex and Q. pubescens in Pinus halepensis (Aleppo pine) woodlands. We investigate the distribution patterns and spatial relationships among oak recruits and resident pines. Established P. halepensis is randomly distributed throughout the study area. Oak seedlings are positively associated with pine trees, suggesting that P. halepensis individuals provide safe sites for oak genet recruitment. We show that spatial patterns of recruitment are in agreement with the general model of spatial segregation described for other Mediterranean plant communities, with seeder species colonizing large openings after disturbance, followed by a more aggregated recruitment of resprouter species.

  15. Attack pattern of Platypus koryoensis (Coleoptera: Curculionidae: Platypodidae) in relation to crown dieback of Mongolian oak in Korea

    Science.gov (United States)

    Jung-Su Lee; Robert A. Haack; Won Il. Choi

    2011-01-01

    The ambrosia beetle, Platypus koryoensis (Murayama), vectors the Korean oak wilt (KOW) pathogen, Raffaelea quercus-mongolicae K.H. Kim, Y.J. Choi, & H.D. Shin, in Korea, which is highly lethal to Mongolian oak, Quercus mongolica Fisch., and is considered a major threat to forest ecosystem health. We...

  16. Effects of soil compaction, forest leaf litter and nitrogen fertilizer on two oak species and microbial activity

    Science.gov (United States)

    D. Jordan; F., Jr. Ponder; V. C. Hubbard

    2003-01-01

    A greenhouse study examined the effects of soil compaction and forest leaf litter on the growth and nitrogen (N) uptake and recovery of red oak (Quercus rubra L.) and scarlet oak (Quercus coccinea Muencch) seedlings and selected microbial activity over a 6-month period. The experiment had a randomized complete block design with...

  17. Impact of the goldspotted oak borer, Agrilus auroguttatus, on the health of coast live oak before and after treatment with two systemic insecticides

    Science.gov (United States)

    Yigen Chen; Mary L. Flint; Tom W. Coleman; Joseph J. Doccola; Donald M. Grosman; David L. Wood; Steven J. Seybold

    2015-01-01

    BACKGROUND: The invasive goldspotted oak borer, Agrilus auroguttatus, is threatening the health and survival of oak trees in San Diego County, California. From two sites in the core area of the infestation, we report a 2.5 year investigation of the impact of A. auroguttatus on coast live oak, Quercus agrifolia, before and after treatment with two systemic...

  18. Distributional record of oak gall wasp (Hymenoptera: Cynipidae ...

    African Journals Online (AJOL)

    m

    2011-11-16

    Nov 16, 2011 ... Species richness of oak gall wasps was estimated for each region and also species diversity indices such as Simpson's index, Shannon's H', and Sorensen similarity quotient were calculated. In this survey, 40 oak gall wasps species were identified. Most galls were found on Quercus infectoria. All of the ...

  19. Acorn storage alternatives tested on Oregon white oak

    Science.gov (United States)

    Warren D. Devine; Constance A. Harrington; Joseph M. Kraft

    2010-01-01

    We assessed various combinations of storage factors: bag type, temperature, duration, and antifungal pre-storage treatments for white oak acorn storage, using Oregon white oak (Quercus garryana Douglas ex Hook. [Fagaceae]) acorns from 7 seed sources. Acorn viability remained high (84%), even after 2 y of refrigerated storage, but the majority of...

  20. Direct Effects of Carpophagous Insects on the Germination Ability and Early Abscission of Oak Acorns

    Directory of Open Access Journals (Sweden)

    CSÓKA, György

    2006-01-01

    Full Text Available Carpophagous insects play an important role in decreasing the viability of acorns in bothdirect and indirect ways. Therefore they significantly influence the reproductive potential of oaks. As adirect effect, their feeding on the embryo and on the cotyledons may prevent the germination of theacorn and on the other hand, their damage causes premature acorn abscission. During 3 years, 60acorn samples from five oak species (Turkey oakQuercus cerris, pedunculate oakQuercus robur,sessile oakQuercus petraea, downy oakQuercus pubescens, red oakQuercus rubra have beeninvestigated. The average rate of damage varied a lot between years, but was always significant (2000:36%, 2001: 61%, 2002: 51%. The insects’ influence causing premature acorn abscission wassignificant both for pedunculate and Turkey oaks. The premature acorn abscission was 34% of thetotal crop in 2000 for pedunculate oak (Curculio spp. 26%, Cydia spp. 2% and Andricusquercuscalicis 6% and 39% in 2001 (Curculio spp. 14%, Cydia spp. 2%, Andricus quercuscalicis13%, Callirhytis glandium 10%. In case of Turkey oak it was 29% in 2001 (C. glandium 16%,Neuroterus saliens 13%, and 12% in 2002 (C. glandium 10%, N. saliens 2%.

  1. Biomarkers identify coast live oaks that are resistant to the invasive pathogen Phytophthora ramorum

    Science.gov (United States)

    Brice A. McPherson; Sylvia R. Mori; Anna O. Conrad; Stephen Opiyo; Pierluigi Bonello; David L. Wood

    2015-01-01

    California coast live oaks (Quercus agrifolia) trees have suffered large losses from sudden oak death, caused by the introduced oomycete Phytophthora ramorum. In this review paper, we discuss oak plant chemistry as a potential predictor of disease susceptibility. We have recorded an annual mortality rate of three percent in...

  2. Response of planted northern red oak seedlings to regeneration harvesting, Midstory removal, and prescribed burning

    Science.gov (United States)

    Stacy L. Clark; Scott E. Schlarbaum; Tara L. Keyser; Callie J. Schweitzer; Marty Spetich; Dean Simon; Gordon S. Warburton

    2016-01-01

    Oak (Quercus) is difficult to naturally regenerate in many mature oak stands on productive sites in the southeastern United States, and artificial regeneration alternatives should be considered. Artificial regeneration can potentially restore or enrich the oak component at the stand level. We examined genetic and silvicultural effects on...

  3. Resilience of California black oak experiencing frequent fire: regeneration following two large wildfires 12 years apart

    Science.gov (United States)

    Ethan J. Hammett; Martin W. Ritchie; John-Pascal Berrill

    2017-01-01

    Historically, oak woodlands in western North America were maintained by frequent fire that killed competing conifers. Today, these woodlands are often in decline as competition from conifers intensifies. Among oak species affected is the ecologically important California black oak (Quercus kelloggii Newberry). Within its range, large high-severity...

  4. Comparison of three sampling methods in the characterization of cork oak stands for management purpose

    NARCIS (Netherlands)

    Paulo, M.J.; Tomé, M.; Otten, A.; Stein, A.

    2005-01-01

    The cork oak (Quercus suber L.) is an evergreen oak that has the ability to produce a continuous layer of cork tissue which regenerates after being removed. Cork oak stands can be diverse in structure. Young stands are often regularly spaced, whereas older stands usually show clustering and can be

  5. Impact of soil scarification on the composition of regeneration and species diversity in an oak shelterwood

    Science.gov (United States)

    James J. Zaczek; Joseph Harding; James Welfley

    1997-01-01

    This study was conducted in a fenced 1-yr-old 70-acre mixed-oak shelterwood to determine the impact of soil scarification on species composition and the production of oak regeneration from abundant northern red oak (Quercus rubra L.) acorns. In October 1993, seven replicates were established and randomly divided into control and scarified plots....

  6. Carbon allocation and morphology of cherrybark oak seedlings and sprouts under three light regimes

    Science.gov (United States)

    Brian Roy Lockhart; Emile S. Gardiner; John D. Hodges; Andrew W. Ezell

    2008-01-01

    Continued problems in regenerating oak forests has led to a need for more basic infomation on oak seedling biology.In the present study, carbon allocation and morphology were compared between cherrybark oak (Quercus pagoda Raf.) seedlings and sprouts at I -Lag grown in full, 47%, and 20% sunlight....

  7. Gambel oak ecology and management in the southern Rockies: The status of our knowledge

    Science.gov (United States)

    Merrill R. Kaufmann; Daniel W. Huisjen; Stanley Kitchen; Mike Babler; Scott R. Abella; Todd S. Gardiner; Darren McAvoy; Josh Howie; Douglas H. Page

    2016-01-01

    Gambel oak is a prominent and ecologically important component of natural vegetation in the Southern Rocky Mountains and Southwest. Woodland and shrub communities dominated by Gambel oak (Quercus gambelii) are widely distributed in Colorado, Utah, Arizona, and New Mexico. Gambel oak has long been recognized to have important benefits and uses such as supplying...

  8. Performance of two oak species and three planting stocks on lands damaged by hurricane Katrina

    Science.gov (United States)

    John A. Conrad III; Andrew W. Ezell; Emily B. Schultz; John D. Hodges

    2015-01-01

    Hurricane Katrina had a devastating impact on bottomland hardwood forests in 2005. Artificial regeneration was considered the most appropriate method for reforesting these areas, but few studies have evaluated methods for artificially regenerating oaks on clear cut sites in the southern United States. First-year survival and growth of two oak species, live oak (Quercus...

  9. Associations among breeding birds and gambel oak in Southwestern ponderosa pine forests

    Science.gov (United States)

    Stephanie Jentsch; R. William Mannan; Brett G. Dickson; William M. Block

    2008-01-01

    Ponderosa pine (Pinus ponderosa) forests with Gambel oak (Quercus gambelii) are associated with higher bird abundance and diversity than are ponderosa pine forests lacking Gambel oak. Little is known, however, about specific structural characteristics of Gambel oak trees, clumps, and stands that may be important to birds in...

  10. Effect of stand density and structure on the abundance of northern red oak advance reproduction

    Science.gov (United States)

    Gary W. Miller

    1997-01-01

    Regenerating northern red oak (Quercus rubra L.) on high-quality growing sites is a continuing problem in the central Appalachian region. Competing species usually exhibit faster height growth after regeneration harvests compared to oak reproduction. The probability of advance oak reproduction becoming codominant in the new stand is positively...

  11. Long-term trends in coast live oak and tanoak stands affected by Phytophthora ramorum canker (Sudden Oak Death)

    Science.gov (United States)

    Tedmund J. Swiecki; Elizabeth Bernhardt

    2010-01-01

    Permanent plots were established in 2000 to examine how tree and site factors affect risk of Phytophthora ramorum stem canker (sudden oak death [SOD]) and determine how affected stands change over time due to disease. P. ramorum canker was prevalent in the sampled coast live oak (Quercus agrifolia) or...

  12. Refining the oak-fire hypothesis for management of oak-dominated forests of the eastern United States

    Science.gov (United States)

    Mary A. Arthur; Heather D. Alexander; Daniel C. Dey; Callie J. Schweitzer; David L. Loftis

    2012-01-01

    Prescribed fires are increasingly implemented throughout eastern deciduous forests to accomplish various management objectives, including maintenance of oak-dominated (Quercus spp.) forests. Despite a regional research-based understanding of prehistoric and historic fire regimes, a parallel understanding of contemporary fire use to preserve oak...

  13. Elemental concentrations in foliage of red maple, red oak, and white oak in relation to atmospheric deposition in Pennsylvania

    Science.gov (United States)

    D. D. Davis; J. M. Skelly; B. L. Nash

    1995-01-01

    Foliage was sampled in June and late August-early September in 1988 and 1989 from the outer crowns of codominant red maple (Acer rubrum L.), northern red oak (Quercus rubra L.), and white oak (Q. alba L.) trees in forest stands along an atmospheric deposition gradient in north-central Pennsylvania. Leaf samples...

  14. Ten-year results of using oak Cleanings to maintain oak species dominance on the Allegheny National Forest

    Science.gov (United States)

    Kurt W. Gottschalk; Gary W. Miller; Robert White; Andrea Hille; Thomas M. Schuler

    2014-01-01

    The Allegheny National Forest (ANF) in northwestern Pennsylvania implemented precommercial thinning in young stands to maintain oak (Quercus spp.) stems in a competitive position. This administrative study was developed to test ANF standards for precommercial thinning for success in maintaining oak composition. An additional objective was to examine...

  15. Germination Characteristics of Engelmann Oak and Coast Live Oak from the Santa Rosa Plateau, Riverside County, California

    Science.gov (United States)

    Gerald E. Snow

    1991-01-01

    Over 2,000 acorns of Quercus agrifolia (coast live oak) and over 500 acorns of Q. engelmannii (Engelmann oak) were collected in the Jim Knight pasture area of the Santa Rosa Plateau. These were used to test for temperature and moisture conditions on germination of viable acorns in the laboratory under controlled environmental...

  16. Biología reproductiva y conservación: el caso de la regeneración de bosques templados y subtropicales de robles (Quercus spp. Plant reproductive biology and conservation: the case of temperate and subtropical oak forest regeneration

    Directory of Open Access Journals (Sweden)

    Fernando J. Pulido

    2002-03-01

    Full Text Available En este trabajo se revisan los resultados de 21 estudios experimentales sobre la regeneración de bosques de roble (Quercus spp. en los que se analizan al menos tres de las fases del ciclo reproductivo: fertilización, desarrollo de frutos viables, dispersión, consumo postdispersivo, germinación-emergencia de plántulas, establecimiento de juveniles y reclutamiento de adultos. La mayoría de las poblaciones estudiadas se encontraban en bosques templados de Norteamérica y Europa, repartidos de forma equitativa entre bosques de ambientes xéricos (incluidos los mediterráneos con especies perennes y habitualmente bajo explotación, y bosques de ambientes mésicos o montanos con especies generalmente caducifolias y escasamente alterados. Los estudios se clasificaron de acuerdo con los tipos de limitación de la regeneración encontrados por los autores, esto es, producción de semillas viables, presión de herbívoros y disponibilidad de sitios seguros. La revisión muestra que en la mayoría de los casos la regeneración se encontraba limitada por una combinación de factores, típicamente el consumo de bellotas y un ambiente abiótico desfavorable durante el establecimiento. La fecundidad de los árboles ha sido rara vez estudiada a pesar de que puede llegar ser en una limitación frecuente, al igual que ocurre con las limitaciones de la dispersión por animales. Finalmente, se analiza el grado de aplicación de la información ecológica acumulada a la solución de problemas de regeneración natural, y se discute su utilidad en comparación con las prácticas más comunes de regeneración artificial via plantacionesThis study presents a review of 21 experimental studies on oak (Quercus regeneration analysing at least three phases of the reproductive cycle, namely fertilization, viable fruit production, acorn dispersal, postdispersal predation, seedling emergence, sapling establishment, and adult recruitment. Most study cases came from North

  17. Photosynthesis and xanthophyll cycle-mediated photoprotection in leaves of Quercus rubra and Q. alba seedlings of different light environments

    Science.gov (United States)

    Shi-Jean S. Sung; Dianpeng Xu; Paul P. Kormanik; Clanton C. Black

    1997-01-01

    Two and three years after the outplanting of 1-0 northern red oak (Quercus rubra, NRO) and white oak (Q. alba, WO) nursery stocks, the highest net photosynthetic rates (Amax) were observed from seedlings growing on a clearcut site, followed by those under a pine stand. Both NRO and WO...

  18. Volatile compounds in Spanish, French, and American oak woods after natural seasoning and toasting.

    Science.gov (United States)

    Cadahía, Estrella; Fernández de Simón, Brígida; Jalocha, Jerzy

    2003-09-24

    The volatile composition (volatile phenols, phenolic aldehydes, furanic compounds, lactones, phenyl ketones, and other related compounds) of Spanish oak heartwood of Quercus robur, Quercus petraea,Quercus pyrenaica, and Quercus faginea was studied by gas chromatography/mass spectrometry, in relation to the processing in barrels cooperage and in relation to the French oak of Quercus robur (Limousin) and Quercus petraea (Allier) and American oak of Quercus alba (Missouri), which are habitually used in cooperage. The volatile composition of seasoned oak woods varied according to individual trees, species, and origins, and the differences were more significant in Spanish species with respect to American species than with respect to French species. The toasting process influenced the volatile composition of wood. It led to high increases in the concentration of volatile phenols, furanic aldehydes, phenyl ketones, and other related structures, but the effect on w-lactones levels depended on species and origin. The volatile composition in Spanish oak species evolved during toasting like in French and American oak, but quantitative differences were found, especially important in American species with respect to European species.

  19. Acorns containing deeper plumule survive better: how white oaks counter embryo excision by rodents.

    Science.gov (United States)

    Zhang, Mingming; Dong, Zhong; Yi, Xianfeng; Bartlow, Andrew W

    2014-01-01

    Several squirrel species excise the embryo of acorns of most white oak species to arrest germination for long-term storage. However, it is not clear how these acorns counter embryo excision and survive in the arms race of coevolution. In this study, we simulated the embryo excision behavior of squirrels by removing 4 mm of cotyledon from the apical end of white oak acorns differing in embryo depths to investigate the effects of embryo excision on acorn germination and seedling performance of white oak species. The embryo depth in the cotyledons was significantly different among white oak acorns, with Quercus mongolica containing the embryo most deeply in the acorns. We found that artificial embryo excision significantly decreased acorn germination rates of Quercus variabilis, Quercus acutissima, Quercus aliena, Quercus aliena var. acutiserrata, Quercus serrata. var. brevipetiolata but not Q. mongolica. Artificial embryo excision exerted significant negative impacts on seedling performance of all oak species except Quercus aliena. Our study demonstrates the role of embryo depth of acorns in countering embryo excision by squirrels and may explain the fact that squirrels do not perform embryo excision in acorns of Q. mongolica with deeper embryos. This apparent adaptation of acorns sheds light on the coevolutionary dynamics between oaks and their seed predators.

  20. Nuttall Oak Volume and Weight Tables

    Science.gov (United States)

    Bryce E. Schlaegel; Regan B. Willson

    1983-01-01

    Volume and weight tables were constructed from a 62-tree sample of Nuttall oak (Quercus nuttallii Palmer) taken in the Mississippi Delta. The tables present volume, green weight, and dry weight of bole wood, bole wood plus bark, and total tree above a one-foot stump as predicted from the nonlinear model Y = 0Db

  1. Field Germination of Nuttall Oak Acorns

    Science.gov (United States)

    R. L. Johnson

    1970-01-01

    In newly cleared plots on Sharkey clay near Stoneville, Mississippi, germination was as high as 79 percent for Nuttall oak (Quercus nuttallii Palmer) acorns sown unstratified in January and 86 percent for those stratified and sown in April. Most seedlings appeared in June and July , when soil temperatures were usually between 80° and 90° F....

  2. HIDROFOBICIDAD EN ANDISOLES BAJO ROBLEDAL (Quercus humboldtii Y PLANTACIONES FORESTALES (Pinus patula y Cupressus lusitanica EN LA CUENCA DE LA QUEBRADA PIEDRAS BLANCAS (MEDELLÍN, COLOMBIA HYDROPHOBICITY OF ANDISOLS OF OAK GROVES (Quercus humboldtii AND TREE PLANTATIONS (Pinus patula and Cupressus lusitanica IN THE PIEDRAS BLANCAS WATERSHED ( MEDELLÍN, COLOMBIA

    Directory of Open Access Journals (Sweden)

    Juan Raúl Duque Zapata

    2004-12-01

    Full Text Available En la cuenca de la quebrada Piedras Blancas se evaluó la persistencia de la repelencia al agua en el horizonte A de Andisoles bajo tres coberturas vegetales: Pinus patula, Cupressus lusitanica y Quercus humboldtii y en tres posiciones topográficas diferentes a lo largo de la vertiente de colinas bajas, mediante el método de WDPT, en muestras con la humedad de campo y secas al aire. En todas las coberturas se encontró repelencia al agua en los suelos. Además, cuando las muestras fueron secadas al aire, la persistencia de la repelencia al agua se incrementó. Se encontró diferencia significativa en la distribución de la persistencia de la repelencia al agua entre las coberturas y entre las posiciones en la vertiente de las colinas, sin que se presentara un comportamiento similar para las tres coberturas. Los suelos bajo cobertura de ciprés fueron los que presentaron los mayores valores de WDPT en todas las condiciones de medida, siendo este el primer reporte que se hace en la literatura, con un amplio respaldo muestral, de repelencia al agua en suelos bajo dicha cobertura vegetal. En ninguno de los casos, la humedad de las muestras fue el parámetro que explicara el comportamiento observado en la repelencia al agua de los suelos estudiados.The persistence of water repellency in the A horizon of Andisols was evaluated in the Piedras Blancas watershed under three vegetative covers: Pinus patula, Cupressus lusitanica, and Quercus humboldtii, and in three different topographic conditions across the slope of a low hill, using the WDPT method with samples containing field humidities and airdried samples. In all vegetative covers, water repellency of the soils was documented. Also, when the samples were air-dried, the persistency of the water repellency increased. A significant difference in the distribution of water repellency was documented among the different vegetative covers and topographic conditions, without a consistent pattern for the

  3. Dental burs and endodontic files: are routine sterilization procedures effective?

    Science.gov (United States)

    Morrison, Archie; Conrod, Susan

    2009-02-01

    The complex miniature architecture of dental burs and endodontic files makes precleaning and sterilization difficult. Devising a sterilization protocol for endodontic files and dental burs requires care, and some have suggested that these instruments be considered single-use devices. One purpose of this study was to determine the effectiveness of various sterilization techniques currently used in dentistry for the resterilization of dental burs and endodontic files. The second aim was to determine whether new dental burs and endodontic files, as supplied in packages from the manufacturer, are sterile. The sterility of new (unused) and used dental burs and endodontic files before and after various sterilization procedures was analyzed. New burs and files were tested immediately after removal from manufacturers" packaging, with or without prior sterilization. Burs and files that had been used in various dental offices were precleaned, packaged, resterilized and then tested for various pathogens. Each item was individually removed from the sterilization packaging, transferred by sterile technique into Todd-Hewitt broth, incubated at 37 degrees C for 72 hours and observed for bacterial growth. Sterilization procedures were 100% effective for unused burs and unused files but were less than 100% effective for all other test groups. Contamination rates following sterilization ranged from 15% for one group of used burs (p = 0.01) to 58% for one group of used files (p sterile and should therefore be sterilized before first use. The resterilization procedures tested here were not adequate, and more rigorous sterilization procedures are needed. If such procedures cannot be devised, these instruments should perhaps be considered single-use devices.

  4. PRODUCTOS FORESTALES NO MADERABLES ASOCIADOS A BOSQUES DE ROBLE Quercus humboldtii Bonpl EN LA VEGA, CAUCA

    OpenAIRE

    ALEJANDRA POTOSÍ GUTIÉRREZ; JUAN CARLOS VILLALBA MALAVER; LIZETH YURANY ARBOLEDA PINO

    2017-01-01

    The Oak Forest (Quercus humboldtii Bonpl) are affected by inappropriate uses, despite the many natural resources they have and have been feedstock of local communities to develop their daily activities. Therefore, Non-Timber Forest Products (NTFPs) from the Oak Forest were identified in the municipality of La Vega, Cauca Department, to classify them according to the use given by the communities. The information was obtained through field observation techniques, interviews and oral communicati...

  5. Optimization of a Green Extraction/Inclusion Complex Formation Process to Recover Antioxidant Polyphenols from Oak Acorn Husks (Quercus Robur Using Aqueous 2-Hydroxypropyl-β-Cyclodextrin/Glycerol Mixtures

    Directory of Open Access Journals (Sweden)

    Katerina Kyriakidou

    2016-02-01

    Full Text Available Aqueous mixtures of glycerol and 2-hydroxypropyl-β-cyclodextrin (CD, two non-toxic eco-friendly substances, were used as a means of extracting antioxidant polyphenols from oak acorn (Quercur robur husks. The process was optimized by implementing a central composite (Box-Behnken experimental design and response surface methodology, taking into consideration the critical parameters (independent variables of glycerol concentration (Cgl, CD concentration (CCD and temperature (T. The assessment of the extraction model was based on three responses: the total polyphenol yield (YTP, the antiradical activity (AAR and the reducing power (PR. The model illustrated that YTP depended significantly on Cgl and CCD, but not on T, whereas both antioxidant properties considered (AAR and PR were temperature-dependent. The maximum predicted YTP was 122.19 mg GAE per g dry husk weight, while the extract obtained under optimized conditions displayed strong antioxidant activity.

  6. Gene expression profiles of different breast cancer cells compared with their responsiveness to fermented mistletoe (Viscum album L.) extracts Iscador from oak (Quercus), pine (Pinus), white fir (Abies) and apple tree (Malus) in vitro.

    Science.gov (United States)

    Eggenschwiler, Jenny; Patrignani, Andrea; Wagner, Ulrich; Rehrauer, Hubert; Schlapbach, Ralph; Rist, Lukas; Ramos, Mac H; Viviani, Angelika

    2006-06-01

    Cytotoxicity assays in vitro (MTT test) showed that the different breast cancer cell lines Kpl-1, MCF-7 and Mfm-223 respond differently to the mistletoe (Viscum album L.) preparations Iscador. Quercus (Qu), Abies (A), Malus (M) and Pinus (P). In order to determine the differences in the responsiveness of the cells more exactly, the gene expression profiles were determined by cells, which were treated with Mistletoe extracts, compared with untreated control cells. Such differences can be analysed in more detail by looking at the gene expression using Human Whole Genome microarray chips (41,000 genes). The results of the transcriptome analyses suggested that Iscador preparations influenced the overregulation of genes regarding immune defense, stress response, apoptosis and cell-cell adhesion pathways. Within the Mfm-223-Zellen was the Genexpression in MCF-7 and Kpl-1. The MCF-7 cells were affected on the genes which are involved in cell-cell contacts whereas Kpl-1 responded to the mistletoe extracts by changing the mRNA levels of the immune and stress response pathways. Concerning the effects of the mistletoe extract, we conclude that Iscador Qu and M have a greater influence on the immune defense and stress response genes whereas Iscador A tends to affect the cell-cell adhesion and cytoskeleton pathways. In summary, cDNA microarray analyses give us information on whether a cancer cell is sensitive to mistletoe extracts in relation to how many genes are significantly overrepresented after mistletoe treatment, and whether a particular mistletoe extract is more effective on a specific cancer cell than the other preparation.

  7. Verification of a useful character for separating the sexes of the goldspotted oak borer, Agrilus coxalis auroguttatus (Coleoptera: Buprestidae)

    Science.gov (United States)

    T.W. Coleman; S.J. Seybold

    2010-01-01

    The goldspotted oak borer, Agrilus coxalis auroguttatus Schaeffer (Coleoptera: Buprestidae), is a new threat to several native oak species in California (CA) (Coleman & Seybold 2008a, b). The beetle larvae feed in and damage the outer xylem, cambium, and phloem of coast live oak, Quercus agrifolia Née (Fagaceae),...

  8. Predicting the economic costs and property value losses attributed to sudden oak death damage in California (2010-2020)

    Science.gov (United States)

    Kent Kovacs; Tomas Václavík; Robert G. Haight; Arwin Pang; Nik J. Cunniffe; Christopher A. Gilligan; Ross K. Meentemeyer

    2011-01-01

    Phytophthora ramorum, cause of sudden oak death, is a quarantined, non-native, invasive forest pathogen resulting in substantial mortality in coastal live oak (Quercus agrifolia) and several other related tree species on the Pacific Coast of the United States. We estimate the discounted cost of oak treatment, removal, and...

  9. Effects of late rotation thinning on light availability and red oak regeneration within a minor stream bottom in Mississippi

    Science.gov (United States)

    Ellen M. Boerger; Brent R. Frey; Andrew W. Ezell; Tracy Hawkins

    2015-01-01

    Recent studies suggest a troubling decline in the abundance of red oak species (Quercus spp., Section Erythrobalanus) in bottomland forests of the southeastern United States. We assessed red oak advance regeneration and associated tree species in relation to light availability in a 77-year-old oak-dominated stand 5 years after late rotation thinning. Residual basal...

  10. Mercury Distribution and Seasonal and Inter annual Variation of Mercury in Oak (Quercus ilex L.) in Almadenejos (Ciudad Real, Spain); Distribucion y Variacion Estacional e Interanual de Mercurio en La Encina (Quercus ilex L.) en el Municipio de Almadenejos (Ciudad Real)

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Alonso, J.; Sierra, M. J.; Millan, R.

    2014-10-01

    Plants that are exposed to environmental pollutants are able to accumulate them in their organs depending on plant species, type of organ or age among others. Evergreen plants can hold stems and leaves of the different age over the same branch. Thus, the amount of contaminants of these former organs could vary with its age because the contamination exposure time is different. The aim of this study is to know in a tree species, the mercury (Hg) distribution in it and the variation of Hg concentration in leaves and stems between consecutive years and along the same year. In order to carry this objective out, three different trees of Quercus ilex L. were selected and two branches were taken from each of them. Such trees are located in Almadenejos, a village from the Almaden mining district (Ciudad Real, Spain), an area well known due to the developed Hg mining activities for centuries. Considering each branch and each year, on average the results show that leaves had higher Hg concentration than stems. Furthermore, the lowest Hg concentration was measured in fruit (acorn). With regard to ageing effect on Hg concentration and taking into account each branch separately, the results show that the older leaves had higher Hg concentration than younger ones. Nevertheless, the oldest stems had not always higher Hg concentration than youngest ones. A seasonal variation in Hg content appeared both in leaves and in stems in 2010, increasing in 6.2 times on average, in about six months. This result suggests that this kind of organs should be analyzed in winter months. Finally, the results show a very high positive correlation between the Hg of the bark and the Hg of the wood in the sampled branches. Such result suggests that if bark is sampled and its Hg content is analyzed, we could know the Hg content in the big branches or in the trunk, avoiding the cutting of the branches or the whole tree. (Author)

  11. Ex-situ conservation of Quercus oglethorpensis in living collections of arboreta and botanical gardens.

    Science.gov (United States)

    Matthew S. Lobdell; Patrick G. Thompson

    2017-01-01

    Quercus oglethorpensis (Oglethorpe oak) is an endangered species native to the southeastern United States. It is threatened by land use changes, competition, and chestnut blight disease caused by Cryphonectria parasitica. The species is distributed sparsely over a linear distance of ca. 950 km. Its range includes several...

  12. Effects of moisture and nitrogen stress on gas exchange and nutrient resorption in Quercus rubra seedlings

    Science.gov (United States)

    K. Francis Salifu; Douglass F. Jacobs

    2008-01-01

    The effects of simulated soil fertility at three levels (poor, medium, and rich soils) and moisture stress at two levels (well watered versus moisture stressed) on gas exchange and foliar nutrient resorption in 1+0 bareroot northern red oak (Quercus rubra) seedlings were evaluated. Current nitrogen (N) uptake was labeled with the stable isotope

  13. Avaliação e caracterização dos principais compostos químicos da aguardente de cana-de-açúcar envelhecida em tonéis de carvalho (Quercus sp. Determination of the main chemical components in Brazilian sugar cane spirit aged in oak (Quercus sp. barrels

    Directory of Open Access Journals (Sweden)

    Clóvis Parazzi

    2008-03-01

    Full Text Available A aguardente de cana-de-açúcar ou cachaça é muito apreciada por seu aroma e sabor característico, que podem melhorar pelo envelhecimento em barris de madeira. Durante o envelhecimento muitas transformações ocorrem e alguns compostos novos podem ser incorporados ou formados, enquanto outros desaparecem. Este estudo teve como objetivo avaliar os efeitos da madeira sobre a qualidade e composição química da aguardente quando envelhecida em barris de carvalho. Doze amostras de aguardentes foram armazenadas em barris de carvalho e em recipientes de vidro, sob as mesmas condições. As amostragens para análises foram realizadas a cada três meses por um período de três anos. Foram determinados os seguintes compostos: teor alcoólico, polifenóis, acetaldeído, acetato de etila, metanol, n-butílico, n-propílico, isobutílico, isoamílico, acidez e cobre. Houve diferença significativa entre as aguardentes armazenadas em barris de madeira e nos recipientes de vidro. As aguardentes armazenadas em barris apresentaram diferenças significativas para todos os elementos analisados, com exceção do n-butílico. Enquanto que as dos recipientes de vidro não apresentaram diferenças significativas, com exceção do acetato de etila, em relação às épocas de amostragem. Os recipientes utilizados e o tempo de armazenamento interferem nas características químicas e na qualidade da aguardente de cana-de-açúcar.Brazilian sugar cane spirit or "cachaça" is very appreciated for its typical aroma and flavour, which can even be improved by ageing the sugar cane spirit in wood barrels. During the ageing period, many transformations may occur and some new compounds can be incorporated or formed while others disappear. The aim of this work was to evaluate the effect of the wood on the quality and chemical composition of sugar cane spirits when aged in oak barrels. Twelve samples of sugar cane spirit were stored in oak barrels and in glass containers

  14. Embryogenesis in Oak species. A review

    Directory of Open Access Journals (Sweden)

    Aranzazu Gomez-Garay

    2014-08-01

    Full Text Available Aim of study: A review on the propagation methods of four Quercus species, namely Q. suber, Q. robur, Q. ilex and Q. canariensis, through somatic embryogenesis and anther embryogenesis are presented.Area of study: The study comprises both Mediterranean and Atlantic oak species located in Spain.Material and Methods: Somatic embryogenesis was induced on immature zygotic embryos of diverse oak species, permitting the multiplication of half-sib families. Induction of haploid embryos and doubled haploids was assayed in both Q. suber and Q. ilex by temperature stress treatments of anthers containing late vacuolated microspores. The haploid origin of the anther embryos has been evaluated by quantitative nuclear DNA analysis through flow cytometry and by DNA microsatellite markers. Genetic transformation of cork oak has also been performed by means of Agrobacterium tumefaciens vectors. Proteomic analysis has been conducted to screen the diverse protein profiles followed by in vitro derived embryos during their development.Research highlights: Successful plant regeneration from both somatic and haploid embryos has been achieved. In the particular case of cork oak, doubled-haploid plants were obtained. Plantlets regenerated from selected parent trees through somatic embryogenesis were acclimated in the greenhouse and in the nursery, and were planted in an experimental plot in the field. Preliminary evaluation of the cork quality of the plants showed a good heritability correlation with the parent trees. This article revises the work of and is dedicated to Dr. M.A. Bueno, who devoted much of her professional life to the research on Biotechnology and Genetics of forest species, leading the Laboratory of Forest Biotechnology at the Spanish Institute of Agronomic Research (INIA.Key words: anther embryogenesis; microspore; pollen; Quercus canariensis; Quercus ilex; Quercus robur; Quercus suber; somatic embryogenesis. 

  15. Shade, leaf growth and crown development of Quercus rubra, Quercus velutina, Prunus serotina and Acer rubrum seedlings.

    Science.gov (United States)

    Gottschalk, Kurt W.

    1994-01-01

    The study was conducted in an open field to determine the optimum irradiance for establishment and growth of two oak species and two major associated woody species. Half-sib seedlings of black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), northern red oak (Quercus rubra L.) and black oak (Q. velutina Lam.) were grown for two years under shade-cloth tents. Eight shade treatments (94, 70, 57, 45, 37, 27, 20 and 8% of full sunlight) with three replications each were used. Measurements were made on seedlings harvested at the end of the first and second growing seasons. In the second year, shading significantly decreased the number of leaves for all species except black cherry, but only significantly decreased leaf area in northern red oak. Shading significantly decreased average leaf size of red maple. Average leaf size of black cherry was largest in the intermediate shade treatments and decreased significantly with increased and decreased shade. Leaf weight/leaf area (mg cm(-2)) increased significantly in a quadratic pattern with decreasing shade for all four species. Leaf area ratio (cm(2) g(-1)) decreased significantly with decreasing shade for all species except red maple in the first year and black oak in the second year. Total branch development increased significantly with decreasing shade in red maple and northern red oak, whereas indeterminate branches increased significantly with decreasing shade only in black cherry, and short branches increased significantly with decreasing shade only in red maple.

  16. y Quercus laurina

    Directory of Open Access Journals (Sweden)

    R. Flores-Velázquez

    2007-01-01

    Full Text Available Se determinaron las características de maquinado con base en la norma ASTM D 1666-87, en las operaciones de cepillado, barrenado, moldurado, torneado y lijado de la madera de Quercus affinis y Quercus laurina. Los mejores resultados de cepillado para Q. affinis se encontraron al combinar el ángulo de corte de 15º y una velocidad de alimentación de 7.5 m·min-1, para Q. laurina no hubo influencia del ángulo de corte. En el barrenado se obtuvieron excelentes resultados con las dos velocidades de giro de broca probadas. Para el moldurado, los resultados para las dos especies fueron excelentes en ambos cortes. En el torneado se encontró que no existe influencia del contenido de humedad para Q. laurina, mientras que para Q. affinis se clasificó como buena para un contenido de humedad menor y excelente para el mayor contenido de humedad. Y para el lijado los resultados fueron excelentes. De acuerdo a los resultados de las pruebas, las dos especies son apropiadas para ser utilizadas por la industria maderera para la elaboración de productos terminados de alta calidad.

  17. The most significant fungi: Agents of wood decay in oak forests of Serbia

    Directory of Open Access Journals (Sweden)

    Milijašević Tanja

    2007-01-01

    Full Text Available The most widely distributed oak species in Serbia are Q. petrea (sessile oak, Q. cerris (Turkey oak and Q. frainetto (Hungarian oak and Quercus robur (common oak, and lignicolous fungi are the major agents of wood decay in natural and coppice oak forests. In this research, 33 species of fungi were identified. Eleven species were described, among which the most significant are: Armillaria mellea, Fomes fomentarius, Hypoxylon deustum Laetiporus sulphureus, Lenzites quercina and Phellinus robustus. This paper presents the morphological characteristics of the most significant identified fungi, their distribution, host plants and significance.

  18. Pollen viability in Quercus robur L.

    Directory of Open Access Journals (Sweden)

    Batos Branislava

    2017-01-01

    Full Text Available The variability of viability (germination rate and the length of pollen tubes of fresh pedunculate oak (Quercus robur L. pollen grains was studied in vitro on a medium containing 15% sucrose. Spatial variability was studied by sampling fresh pollen grains from a total of thirteen trees at four different sites in the area of Belgrade (Košutnjak, Banovo Brdo, Ada Ciganlija and Bojčin Forest in a single year (2011. In order to assess temporal variability and determine the effects of climate change on a small time scale, we studied the viability of the pollen grains collected from one tree at the Banovo Brdo site in six different years (2004, 2005, 2006, 2007, 2011 and 2012. Interindividual variability was tested on the pollen grains sampled from eight trees at Ada Ciganlija in 2004. The percentage values of the pollen grain germination rate and the pollen tube length showed no statistically significant differences between the sites. However, the studied characteristics of the pollen grain viability (germination rate and pollen tube length showed statistically significant differences in both temporal (between the pollen collection years and interindividual variability. This type of research makes a valuable contribution to pedunculate oak breeding programs through the identification of trees with stable production and a good quality of pollen. Furthermore, it can be important in defining the patterns of spatial, temporal and individual variability of pollen grain viability under the influence of climate factors, which are showing compelling changing trends from year to year.

  19. First discovery of Quercus feeding Nepticulidae (Lepidoptera) in Central America.

    Science.gov (United States)

    Stonis, Jonas R; Diškus, Arūnas; Remeikis, Andrius; Schuster, Jack

    2013-11-18

    Despite the high taxonomic diversity of oaks in Mexico and Central America, no Quercus feeding Nepticulidae have ever been recorded from the region. Here, we present seven species whose larvae are leaf-miners of Quercus (section Lobatae) in Guatemala. Except Stigmella nigriverticella (Chambers 1875), which was previously known from the United States, all other discovered species are new. We describe and name five new species (Stigmella jaguari Remeikis & Stonis, sp. nov., S. lauta Diškus & Stonis, sp. nov., S. sublauta Remeikis & Stonis, sp. nov., S. aurifasciata Diškus & Stonis, sp. nov. and S. guatemalensis Diškus & Stonis, sp. nov.); the remaining new species is described but left unnamed because of lack of adults (i. e. moths and genitalia are described from developed pupae). All seven treated species are illustrated with photographs of the leaf-mines, adults, and genitalia.

  20. Sprouting productivity and allometric relationships of two oak species managed for traditional charcoal making in central Mexico.

    NARCIS (Netherlands)

    Aguilar, R.; Ghilardi, A.; Vega, E.; Skutsch, Margaret; Oyama, K.

    2012-01-01

    Sustainable production systems for woodfuels in developing countries require basic information on tree productivity, and particularly on their coppicing productivity under current forms of management. We report biomass equations and sprouting productivity of two oak species (Quercus castanea and

  1. Disinfection of dental diamond burs contaminated with hepatitis B virus.

    Science.gov (United States)

    Leontiou, A P; Coogan, M M; Aspinall, S

    1999-09-01

    Hepatitis B infection (HBV) is a significant hazard in the dental environment because the virus may be transmitted through contaminated dental instruments. This study determined whether cold disinfectants can inactivate HBV DNA and HBV surface antigens on diamond burs contaminated with HBV and whether ultrasonication can increase the antiviral properties of these agents. Sterile dental diamond burs were contaminated with serum from a patient who tested positive for HBV surface antigen and hepatitis B viral DNA. The burs were air dried and placed in solutions containing either Cidex, Asepsys, TBS, Rotagerm, Virkon disinfectants, or a control phosphate buffered saline. Burs were divided into 2 groups and disinfected for 15 minutes. The first group was ultrasonicated; the second group was not ultrasonicated during disinfection. All the burs were transferred to phosphate buffered saline and ultrasonicated to remove any remaining viral particles. The ultrasonicate was tested for the presence of HBV surface antigen with a microparticle enzyme immunoassay and for hepatitis B viral DNA with a chemiluminescent molecular hybridization assay. TBS did not require ultrasonication to inactivate viral DNA and surface antigen. Rotagerm and Virkon inactivated surface antigen and viral DNA only with ultrasonication. Cidex and Asepsys inactivated viral DNA but not surface antigen with ultrasonication. The chlorine containing compound TBS was the most active disinfectant tested and did not require ultrasonication to destroy HBV. The remaining disinfectants should be used with ultrasonication to inactivate HBV.

  2. Prescribed fire and oak sapling physiology, demography, and folivore damage in an Ozark woodland

    Science.gov (United States)

    D. Alexander Wait; Douglas P. Aubrey

    2014-01-01

    Prescribed fire is a tool in wildlife management for restoring and maintaining midwestern oak woodlands. The success of some of the wildlife management objectives depends upon opening the canopy, new oak (Quercus spp.) saplings entering the canopy, and removal of cedar (Juniperus virginiana L.). We examined population...

  3. Metabolite profiling to predict resistance to Phytophthora ramorum in natural populations of coast live oak

    Science.gov (United States)

    A. Conrad; B. Mcpherson; D. Wood; S. Opiyo; S. Mori; P. Bonello

    2013-01-01

    Sudden oak death, caused by the invasive oomycete pathogen Phytophthora ramorum, continues to shape the dynamics of coastal populations of oak (Quercus spp.) and tanoak (Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh) in California and tanoak in southwestern Oregon. Over the...

  4. Relationship between field resistance to Phytophthora ramorum and constitutive phenolic chemistry of coast live oak

    Science.gov (United States)

    A.M. Nagle; B.A. McPherson; D.L. Wood; M. Garbelotto; A.O. Conrad; S. Opiyo; P. Bonello

    2012-01-01

    Sudden oak death, caused by Phytophthora ramorum, has resulted in high levels of coast live oak (Quercus agrifolia Nee (CLO) mortality. However, some CLO survive in areas with high disease pressure and may thus be resistant. We tested the hypothesis that such field resistant trees contain constitutively higher levels of...

  5. Phytophthora ramorum in coast live oak: search for resistance and mechanisms.

    Science.gov (United States)

    B.A. McPherson; D.L. Wood; S.R. Mori; A. Conrad; P. Bonello

    2013-01-01

    Despite the presence of Phytophthora ramorum in northern and central California forests since at least 1994, asymptomatic coast live oaks (Quercus agrifolia Née) still remain in heavily infested stands. Coast live oak infection and mortality rates of 5 percent y-1 and 3 percent y-1, respectively, observed in long-term...

  6. Development of northern red oak rooted cutting and enrichment planting systems

    Science.gov (United States)

    Matthew H. Gocke; Jamie Schuler; Daniel J. Robison; Barry Goldfarb

    2005-01-01

    Enrichment planting may provide an efficient means to establish elite northern red oak (Quercus rubra L.) genotypes in recently harvested natural forests. However, planting northern red oak (NRO) seedlings into natural stands has proven difficult in the past, especially when competition and other stress factors are not controlled.

  7. Effects of wildfire on blue oak in the northern Sacramento Valley

    Science.gov (United States)

    Marc Horney; Richard B. Standiford; Douglas McCreary; Jerry Tecklin; Roy Richards

    2002-01-01

    The objective of this project was to develop a technique for rapidly determining the extent of wildfire damage to blue oaks (Quercus douglasii) that would be usable by landowners without requiring extensive training. In late winter 2000, 100 oaks of various sizes and degrees of damage were selected from 10 plots located where wildfires had burned in...

  8. Crop tree release improves competitiveness of northern red oak growing in association with black cherry

    Science.gov (United States)

    Thomas M. Schuler

    2006-01-01

    In 1993, a crop tree study was established in a pole-sized stand consisting of black cherry (Prunus serotina Ehrh.) and northern red oak (Quercus rubra L.). Black cherry was the predominant species in the stand and appeared to be on the verge of virtually eliminating northern red oak based on its greater height growth potential. To assess crop tree management for...

  9. Influence of flooding, freezing, and American beaver herbivory on survival of planted oak seedlings

    Science.gov (United States)

    Johnathan T. Reeves; Andrew W. Ezell; John D. Hodges; Emily B. Schultz; Andrew B. Self

    2016-01-01

    Good seedlings, proper planting, and competition control normally result in successful hardwood planting. However, other factors can have serious impact on planting success, such as the impact of flooding, freezing, and the American beaver (Castor canadensis). In 2014, three planting stocks of Nuttall oak (Quercus nuttallii) and Shumard oak (

  10. A stand-development approach to oak afforestation in the lower Mississippi alluvial valley

    Science.gov (United States)

    Brian Roy Lockhart; Emile Gardiner; Theodor Leininger; John Stanturf

    2008-01-01

    Oak (Quercus spp.) afforestation in the Lower Mississippi Alluvial Valley has involved planting 1-year-old bareroot seedlings on a relatively wide spacing in single-species stands or planting light-seeded species with oaks to form mixed-species stands. In the former case, the developing single-species stands have limited future management options...

  11. Response of Advance Cherrybark Oak Reproduction to Midstory Removal and Shoot Clipping

    Science.gov (United States)

    Brian R. Lockhart; John D. Hodges; Emile S. Gardiner

    2000-01-01

    A Midstory competition control and shoot clipping have been proposed to increase the vigor and height of advance bottomland oak reproduction. Results from a study in east-central Mississippi showed that advance cherrybark oak (Quercus pagoda Raf) released from midstory competition had greater survival than nonreleased seedlings, 64% and 48%,...

  12. Anthropogenic fire history and red oak forests in south-central Ontario

    Science.gov (United States)

    Daniel C. Dey; Richard P. Guyette

    2000-01-01

    The regeneration and dominance of northern red oak (Quercus rubra L.) has been associated with fire throughout eastern North America. Red oak in central Ontario grows near the northern edge of its distribution in mixed hardwood - coniferous forests under mesic conditions where it competes with more shade-tolerant species. We hypothesized that the...

  13. Evaluating the use of enhanced oak seedlings for increased survival and growth: first-year survival

    Science.gov (United States)

    Joshua L. Moree; Andrew W. Ezell; John D. Hodges; Andrew J. Londo; K. David Godwin

    2010-01-01

    Oaks (Quercus spp.) are very important in the southern landscape for timber production and wildlife habitat. More landowners are attempting to establish oak plantations as the demand for wood products and wildlife habitat continues to increase. These attempts are not always successful with early growth and survival becoming major concerns. In this...

  14. The Effect of Land Use Changes on Blue Oak Regeneration and Recruitment

    Science.gov (United States)

    Scott Mensing

    1991-01-01

    Lack of blue oak (Quercus douglasii) saplings and seedlings throughout much of its range has prompted research into the regeneration status of the species. Our ability to assess whether the current lack of regeneration is a natural pattern or a response to human induced environmental change is limited by lack of data on the history of blue oak...

  15. Visual Grading and Quality of 1-0 Northern Red Oak Seedlings

    Science.gov (United States)

    S.L. Clark; S.E. Scblarbaum; Paul P. Kormanik

    2000-01-01

    Past research has used detailed measurements of various growth characteristics to determine seedling grades and quality of northern red oak nursery stock This study evaluates the effectiveness ofa visual grading process. similar to thosefound in commercial nursery operations, to distinguish high quality seedlings. Northern red oak (Quercus rubra...

  16. A spatial statistical analysis of cork oak competition in two Portuguese silvopastoral systems

    NARCIS (Netherlands)

    Paulo, M.J.; Stein, A.; Tomé, M.

    2002-01-01

    This paper considers competition among cork oaks (Quercus suber L.) at three plots in two representative Portuguese stands. It uses spatial point pattern functions to describe densities and quantify differences among stands. Relations between cork oak characteristics and indices measuring intertree

  17. The effect of small rodents on northern red oak acorns in north-central West Virginia

    Science.gov (United States)

    Linda S. Gribko; David M. Hix

    1993-01-01

    The effects of small mammals on surface-sown northern red oak (Quercus rubra) acorns was assessed in highly productive Appalachian hardwood stands. Study plots were established in October 1990 on excellent (average site index of 89 feet for red oak) and good (average site index of 72 feet) sites. Each plot included: 1) a rodent-proof exclosure, 2) an exclosure...

  18. Artificial Regeneration of Blue and Coast Live Oaks in the Central Coast

    Science.gov (United States)

    Tim R. Plumb; Bennie Hannah

    1991-01-01

    The primary goal of this study was to find economical and effective planting techniques that will ensure the establishment and early survival of coast live oak (Quercus agrifolia Née) and blue oak (Q. douglasii H. and A.) in the Central Coast region of California. Eight treatments were evaluated ranging from unprotected seed spots...

  19. A stand-development approach to oak afforestation in the Lower Mississippi Alluvial Valley

    Science.gov (United States)

    J. Stanturf

    2009-01-01

    Oak (Quercus spp.) afforestation in the Lower Mississippi Alluvial Valley has involved planting 1-year-old bareroot seedlings on a relatively wide spacing in single-species stands or planting light-seeded species with oaks to form mixed-species stands. In the former case, the developing single-species stands have limited future...

  20. Mycorrhizae promote fire adaptation in oak-hickory forests in Eastern USA

    Science.gov (United States)

    Aaron D. Stottlemyer; G. Geoff Wang; Thomas A. Waldrop

    2015-01-01

    Prescribed fire is commonly used in silvicultural programs designed to promote oak (Quercus spp.) and hickory (Carya spp.) regeneration in eastern deciduous forests (Brose and others 2008). Thick bark, hypogeal germination, large root systems, repeated-prolific sprouting, and the ability to compartmentalize scars are well-known characteristics that enable oaks and...

  1. Attraction of ambrosia and bark beetles to coast live oaks infected by Phytophthora ramorum

    Science.gov (United States)

    Brice A. McPherson; Nadir Erbilgin; David L. Wood; Pavel Svihra; Andrew J. Storer; Richard B. Standiford

    2008-01-01

    Sudden oak death, caused by Phytophthora ramorum (Werres, de Cock & Man in?t Veld), has killed thousands of oaks (Quercus spp.) in coastal California forests since the mid-1990s. Bark and ambrosia beetles that normally colonize dead or severely weakened trees selectively tunnel into the bleeding cankers that are the first...

  2. Recent advances in the control of oak wilt in the United States

    Science.gov (United States)

    Dan A. Wilson

    2005-01-01

    Oak wilt, caused by Ceratocystis fagacearum (T.W.Bretz) J. Hunt, is probably the most destructive disease of oak trees (Quercus species) in the United States, and is currently causing high morality at epiphytotic proportions in central Texas. The serious potential for damage pro,pted an increase in federal funding within the past...

  3. Evaluating desiccation sensitivity of northern red oak acorns using x-ray image analysis

    Science.gov (United States)

    Rosa C. Goodman; Douglass F. Jacobs

    2005-01-01

    Desiccation of northern red oak (Quercus rubra L.) acorns can have a major influence on seed viability. Recalcitrant behavior of northern red oak acorns was studied to examine the effects of moisture content (MC) on germination and early growth. Because it is rapid and non-destructive, X-ray image analysis was chosen to assess cotyledon damage in...

  4. Twenty-nine years of development in planted cherrybark oak-sweetgum mixtures: implications for future mixed-species hardwood plantations

    Science.gov (United States)

    Brian Roy Lockhart; Andrew W. Ezell; John D. Hodges; Wayne K. Clatterbuck

    2012-01-01

    Results from a long-term planted mixture of cherrybark oak (Quercus pagoda Raf.) and sweetgum (Liquidambar styraciflua L.) showed sweetgum taller in height and larger in diameter than cherrybark oak early in plantation development. By age 17, cherrybark oak was similar in height and diameter with sweetgum and by age 21 was taller...

  5. Using natural stand development patterns in artificial mixtures: a case study with cherrybark oak and sweetgum in east-central Mississippi, USA

    Science.gov (United States)

    Brian Roy Lockhart; Andrew W. Ezell; John D. Hodges; Wayne K. Clatterbuck

    2006-01-01

    Results from a long-term planted mixture of cherrybark oak (Quercus pagoda Raf.) and sweetgum (Liquidambar styraciflua L.) showed sweetgum taller in height and larger in diameter than cherrybark oak early in plantation development. By age 17 years, cherrybark oak was similar in height and diameter with sweetgum and by age 21...

  6. A comparison of the effects of different shelterwood harvest methods on the survival and growth of acorn-origin oak seedlings

    Science.gov (United States)

    Patrick H. Brose

    2011-01-01

    Timely development of newly germinated oak (Quercus spp.) seedlings into competitive-sized regeneration is an essential part of the oak regeneration process. The amount of sunlight reaching the forest floor partly governs this development, and foresters often use the shelterwood system to expose oak seedlings to varying degrees of insolation. To...

  7. Development of water oak stump sprouts under a partial overstory

    Science.gov (United States)

    Emile S. Gardiner; Lisa M. Helmig

    1997-01-01

    A 28-year-old water oak (Quercus nigra L.) plantation was thinned from below to either 254 or 462 stems per hectare to determine the influence of a partial canopy on oak stump sprout development. Sprout clump survival, number of living sprouts in a clump, and height and DBH of the dominant sprout in a clump were measured in years l-5 and 7 after harvest. By year 7,...

  8. A novel simplified numbering system for dental burs

    Directory of Open Access Journals (Sweden)

    Hemamalathi Senthil

    2008-01-01

    Full Text Available A universally accepted standardization is of great value for any material or equipment that is used globally. A single number or name should represent the particular material or instrument throughout the world. Since the dental burs are used worldwide, a single standard numbering system, which gives a unique specification for each bur in any part of the world, is mandatory. Though the existing systems have tried to attain this goal, they have their own advantages and limitations that are explained in detail in this article. So, the idea of proposing a novel system is to formulate a simple way of mentioning each bur with its dimension and composition without the need for memorizing the numbers.

  9. The chamfer finish line: preclinical student performance using different bur designs

    National Research Council Canada - National Science Library

    Mansueto, Michael A; Abdulkarim, Hatem A; Thabet, Walid R; Haney, Stephan J

    2010-01-01

    The primary purposes of this investigation were to evaluate sophomore dental student performance in the production of a chamfer finish line using two diamond bur types-a round-ended bur and a torpedo...

  10. Thinning interior live oak in California's Southern Sierra Nevada

    Science.gov (United States)

    Richard B. Standiford; Neil K. McDougald

    2015-01-01

    This study describes a thinning and resprout control study in Madera County. The study site was a dense, 40-year old interior live oak stand (Quercus wislizeni) that originated from resprouting, with 100 percent canopy cover. Tree thinning was initiated in 1998 in cooperation with the local Resource Conservation District to evaluate thinning...

  11. Leaf gas exchange of mature bottomland oak trees

    Science.gov (United States)

    Rico M. Gazal; Mark E. Kubiske; Kristina F. Connor

    2009-01-01

    We determined how changes in environmental moisture affected leaf gas exchange in Nuttall (Quercus texana Buckley), overcup (Q. lyrata Walt.), and dominant and codominant swamp chestnut (Q. michauxii Nutt.) oak trees in Mississippi and Louisiana. We used canopy access towers to measure leaf level gas...

  12. Shelterwood-planted northern red oaks: integrated costs and options

    Science.gov (United States)

    Martin A. Spetich; Daniel Dey; Paul. Johnson

    2009-01-01

    Tree biology, environmental site conditions, relative monetary costs, management options, and the competitive struggle between planted trees and other vegetation were integrated when underplanting northern red oak (Quercus rubra L.) seedlings in Boston Mountain shelterwoods. This approach provides insight into the collective costs (...

  13. Photosynthate distribution patterns in cherrybark oak seedling sprouts

    Science.gov (United States)

    Brian Roy Lockhart; John D. Hodges; Emile S. Gardiner; Andrew W. Ezell

    2003-01-01

    Summary We used 14C tracers to determine photosynthate distribution in cherrybark oak (Quercus pagoda Raf.) seedling sprouts following release from competing mid-story vegetation. Fall acquisition of labeled photosynthates by seedlings followed expected source--sink patterns, with root and basal stem tissues...

  14. Coarse woody debris in oak woodlands of California.

    Science.gov (United States)

    William D. Tietje; Karen L. Waddell; Justin K. Vreeland; Charles L. Bolsinger

    2002-01-01

    An extensive forest inventory was conducted to estimate the amount and distribution of coarse woody debris (CWD) on 5.6 million ac of woodlands in California that are outside of national forests and reserved areas. Woodlands consist primarily of oak (Quercus spp.) types and are defined as forestland incapable of producing commercial quantities of...

  15. Oak regeneration and overstory density in the Missouri Ozarks

    Science.gov (United States)

    David R. Larsen; Monte A. Metzger; Paul S. Johnson

    1997-01-01

    Reducing overstory density is a commonly recommended method of increasing the regeneration potential of oak (Quercus) forests. However, recommendations seldom specify the probable increase in density or the size of reproduction associated with a given residual overstory density. This paper presents logistic regression models that describe this...

  16. A mono harvest of California black oak acorns

    Science.gov (United States)

    Jonathan W. Long; Ron W. Goode

    2017-01-01

    In about 1925 or 1926, Margaret Baty, a tribal member of Big Sandy Rancheria, displayed a collection of acorns from California black oak (Quercus kelloggii, wi-yap' in Mono) and an acorn cooking basket. This photograph, taken by George Holt and courtesy of the Flegal Collection of the Jesse Peter Museum at Santa Rosa Junior College,...

  17. Detection of defects in red oak deckboards by ultrasonic scanning

    Science.gov (United States)

    Mohammed F. Kabir; Daniel L. Schmoldt; Mark E. Schafer

    2000-01-01

    Experiments were conducted to detect defects in red oak (Quercus rubra, L.) deckboards by ultrasonic scanning. Scanning of the deckboards was carried out with two rolling transducers in a pitch-catch arrangement with pallet parts moving between the transducers at 70 ft/m and 220 ft/m. Data were collected, stored and processed using LabViewTM software. The defects...

  18. Estimating the relative nutrient uptake from different soil depths in Quercus robur, Fagus sylvatica and Picea abies

    DEFF Research Database (Denmark)

    Göransson, Hans; Wallander, Håkan; Ingerslev, Morten

    2006-01-01

    uptake capacity of Rb+ and NH4+ by these fine roots under standardized conditions in the laboratory. The study was performed in monocultures of oak (Quercus robur L.), European beech (Fagus sylvatica L.) and Norway spruce [Picea abies (L.) Karst.] on sandy soil in a tree species trial in Denmark...

  19. The influence of cultural treatments of the long-term survival and growth of planted Quercus rubra

    Science.gov (United States)

    James J. Zaczek; Kim C. Steiner

    2011-01-01

    A northern red oak (Quercus rubra L.) plantation testing 20 nursery stock and planting methods was used to evaluate treatments 3, 6, 10, and 17 years after planting. Survival over all treatments was 92 percent at age 3 and declined to 74 percent, 56 percent, and 39 percent at ages 6, 10, and 17, respectively. At age 17, survival was highest for...

  20. High-light acclimation in Quercus robur L.seedlings upon over-topped a shaded environment

    Science.gov (United States)

    Anna M. Jensen; Emile S. Gardiner; Kevin C. Vaughn

    2012-01-01

    High developmental plasticity at the seedling-level during acclimation to the light environment may be an important determinant of seedling establishment and growth in temperate broadleaf forests, especially in dense understories where spatial light availability can vary greatly. Pedunculate oak (Quercus robur L.) seedlings were raised beneath a...

  1. Winter variation in physiological status of cold stored and freshly lifted semi-evergreen quercus nigra seedlings

    Science.gov (United States)

    Rosa C. Goodman; Douglass F. Jacobs; Kent G. Apostol; Barrett C. Wilson; Emile S. Gardiner

    2009-01-01

    Water oak (Quercus nigra L.) is a tardily deciduous species commonly planted in afforestation projects in the Lower Mississippi River Alluvial Valley, USA. Field performance is often marked by low survival rates and top dieback, which may be associated with poor physiological quality of planting stock.

  2. Root desiccation and drought stress responses of bareroot Quercus rubra seedlings treated with a hydrophilic polymer root dip

    Science.gov (United States)

    Kent G. Apostol; Douglass F. Jacobs; R. Kasten Dumroese

    2009-01-01

    Root hydrogel, a hydrophilic polymer, has been used to improve transplanting success of bareroot conifer seedlings through effects on water holding capacity. We examined mechanisms by which Terra-sorb Fine Hydrogel reduces damage that occurs when roots of 1-year old, dormant northern red oak (Quercus rubra L.) were subjected to shortterm (1, 3, and 5...

  3. Evaluation of efficiency of different decontamination methods of dental burs: An In vivo study

    Directory of Open Access Journals (Sweden)

    Abirami Mathivanan

    2017-01-01

    Full Text Available Introduction: Infection control is very important in dentistry. Both dentist and patients are at risk of communicating diseases during treatment procedures. Dental burs have been identified as a source of cross-contamination between patient and dental personnel. Aim: The present study was done to quantitatively and qualitatively assess the pathogenic contamination of dental burs used for tooth preparation and to determine the effective method of sterilization(autoclave,glass bead sterilizer, hot air oven and surgical spirit immersion of burs used for crown preparation. Methodology: Dental burs were assessed before and after tooth preparation,also after sterilization burs were evaluated. Conclusion: Findings of our study revealed that among the experimental groups used in the present study, Autoclave and Hot air oven was found to be the relatively best method to sterilize burs. Proper cleaning and sterilization of burs should be strictly employed to prevent cross contamination in clinical practice.

  4. Effects of leaf area of downy oak (Quercus pubescens Willd ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-08-18

    Aug 18, 2009 ... 2nd ages of the seedlings were determined by a digital caliper with sensitivity of 0.001 mm (Mitutoyo absolute digimatic caliper). The diameter increment of the seedling is calculated by the means of relations between diameter increment of 2nd age, height increment of 1st and 2nd ages and by the means of ...

  5. Sessile oak (Quercus petraea agg. Ehrendorfer 1967) rare ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-09-01

    Sep 1, 2009 ... Silvae Genetica, 57(4-5): 227-234. Taberlet P, Gielly L, Patou G, Bouvet J (1991). Universal primers for amplification of three non-coding regions of chloroplast DNA. Plant. Mol. Biol. 17: 1105-1109. Tatić B, Tomić Z (2006). Šume crnog i belog bora. Vegetacija Srbije II. 2, SANU (Ur. D. Škorić), Beograd.

  6. Antimicrobial effects of Quercus ilex L. extract.

    Science.gov (United States)

    Güllüce, M; Adigüzel, A; Oğütçü, H; Sengül, M; Karaman, I; Sahin, F

    2004-03-01

    The antimicrobial activities of the methanol extract of Quercus ilex L. (Pirnal oak) leaves were tested in vitro against a wide range of human and plant-associated microorganisms. A total of 132 microbial organisms belonging to 55 bacteria and five fungi and yeast species were studied using a disc-diffusion method and microdilution assays. The results were evaluated as inhibition zones around the disc impregnated with Q. ilex extract at a concentration of 300 micro L/mL. The results showed that Q. ilex did not have any antifungal activities against Alterneria alternata, Aspergillus flavus, Fusarium oxysporum, Penicillum spp., whereas there were inhibition effects on the growth of all Candida albicans isolates. In total 97 bacterial strains (74%) were found to be resistant to Q. ilex extract. The remaining 35 (27%) strains of seven different bacteria genera including Brucella, Bacillus, Enterobacter, Neisseria, Pseudomonas and Escherichia were susceptible to the extract tested. The minimum inhibitory concentrations (MIC) of the extract ranged from 125 to 500 micro L/mL. These results suggest that Q. ilex possesses compounds with antibacterial and anticandidal properties. Copyright 2004 John Wiley & Sons, Ltd.

  7. INVESTIGATION ON THE PROPERTIES OF PEDUNCULATE OAK WOOD AFFECTED BY OAK DECLINE

    Directory of Open Access Journals (Sweden)

    Dumitru LICA

    2014-12-01

    Full Text Available The combination of damaging agents, as biotic and abiotic factors, has as effect the deterioration in the appearance of the foliage of affected trees and then, progressive death of branches. Large numbers of pedunculate oak (Quercus robur and sessile oak (Quercus petraea trees are declining in the Central Romania. Depending on the deterioration of the foliage and of the branches, five grades of infestation levels of oak trees were determined. The objective of this study was to investigate the quality of wood obtained from those infested trees by analysing the cellulose and lignin content, physical properties such as moisture content, density, shrinkage from fibre saturation moisture content, permeability of wood to water, and mechanical properties, such as MOE, MOR for static stresses, tensile strength perpendicular to the grains, shearing strength and Janka hardness perpendicular to the grains. The more representative samples of trees affected by oak decline for the five grades of infestation levels of trees were randomly selected and harvested. They were cut into logs and then sampled for the chemical, physical and mechanical testing. The results of this study showed that the poor quality of wood resulted from the logs affected by oak decline at the final stage (five grade of infestation level could not be used for furniture and other wooden products manufacturing.

  8. Contrasting the effects of organic matter removal and soil compaction on root biomass of 9-year-old red oak, white oak, and shortleaf pine in a Missouri Ozark forest

    Science.gov (United States)

    Felix Jr. Ponder

    2011-01-01

    Nine-year old artificially regenerated red oak (Quercus rubra L.), white oak (Q. alba L.), and shortleaf pine (Pinus echinata Mill.) trees were excavated from plot borders of a U.S. Forest Service long-term soil productivity study in the Carr Creek State Forest near Ellington, MO, to quantify treatment effects on...

  9. Antioxidant Characterization of Oak Extracts Combining Spectrophotometric Assays and Chemometrics

    Directory of Open Access Journals (Sweden)

    Boris M. Popović

    2013-01-01

    Full Text Available Antioxidant characteristics of leaves, twigs, and acorns from two Serbian oak species Quercus robur L. and Quercus petraea L. from Vojvodina province (northern Serbia were investigated. 80% ethanol (in water extracts were used for antiradical power (ARP determinations against DPPH•, NO•, and O2∙- radicals, ferric reducing antioxidant power (FRAP, total phenol, tannin, flavonoid, and proanthocyanidin contents. Permanganate reducing antioxidant capacity (PRAC was determined using water extracts. Beside, mentioned parameters, soluble proteins, lipid peroxidation (LP, pigments and proline contents were also determined. The data of different procedures were compared and analyzed by multivariate techniques (correlation matrix calculation and principal component analysis (PCA. PCA found that investigated organs of two different oak tree species possess similar antioxidant characteristics. The superior antioxidant characteristics showed oak leaves over twigs and acorns and seem to be promising source of antioxidants with possible use in industry and pharmacy.

  10. Fragmentation patterns of evergreen oak woodlands in Southwestern Iberia

    DEFF Research Database (Denmark)

    Costa, A.; Madeira, M.; Lima Santos, J.

    2014-01-01

    Mediterranean evergreen oak woodlands (composed of Quercus suber L. and Quercus rotundifolia Lam.) are becoming increasingly fragmented in the human-modified landscapes of Southwestern Portugal and Spain. Previous studies have largely neglected to assess the spatial changes of oak woodlands...... in relation to their surrounding landscape matrix, and to characterize and quantify woodland boundaries and edges. The present study aims to fill this gap by analyzing fragmentation patterns of oak woodlands over a 50-year period (1958-2007) in three landscapes. Using archived aerial imagery from 1958, 1995...... and 2007, for two consecutive periods (1958-1995 and 1995-2007), we calculated a set of landscape metrics to compare woodland fragmentation over time. Our results indicated a continuous woodland fragmentation characterized by their edge dynamics. From 1958 to 2007, the replacement of open farmland...

  11. Responses of evergreen and deciduous Quercus species to enhanced ozone levels

    Energy Technology Data Exchange (ETDEWEB)

    Calatayud, Vicent, E-mail: calatayud_viclor@gva.e [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Cervero, Julia; Calvo, Esperanza [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Garcia-Breijo, Francisco-Jose [Laboratorio de Anatomia e Histologia Vegetal ' Julio Iranzo' , Jardin Botanico, Universitat de Valencia, c/Quart 80, 46008 Valencia (Spain); Departamento de Ecosistemas Agroforestales, Escuela Tecnica Superior del Medio Rural y Enologia, Universidad Politecnica de Valencia, Avda. Blasco Ibanez 21, 46010 Valencia (Spain); Reig-Arminana, Jose [Departamento de Ecosistemas Agroforestales, Escuela Tecnica Superior del Medio Rural y Enologia, Universidad Politecnica de Valencia, Avda. Blasco Ibanez 21, 46010 Valencia (Spain); Sanz, Maria Jose [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain)

    2011-01-15

    Plants of one evergreen oak (Quercus ilex) and three deciduous oaks (Q. faginea, with small leaves; Q. pyrenaica and Q. robur, with large leaves) were exposed both to filtered air and to enhanced ozone levels in Open-Top Chambers. Q. faginea and Q. pyrenaica were studied for the first time. Based on visible injury, gas exchange, chlorophyll content and biomass responses, Q. pyrenaica was the most sensitive species, and Q. ilex was the most tolerant, followed by Q. faginea. Functional leaf traits of the species were related to differences in sensitivity, while accumulated ozone flux via stomata (POD{sub 1.6}) partly contributed to the observed differences. For risk assessment of Mediterranean vegetation, the diversity of responses detected in this study should be taken into account, applying appropriate critical levels. - Ozone tolerance overlapped with leaf traits in four Quercus species.

  12. Increasing distance from California bay laurel reduces the risk and severity of Phytophthora ramorum canker in coast live oak

    Science.gov (United States)

    Tedmund J. Swiecki; Elizabeth A. Bernhardt

    2008-01-01

    Foliar infections in California bay (Umbellularia californica) are the most important known source of inoculum contributing to Phytophthora ramorum canker in coast live oak (Quercus agrifolia). This research addressed the question whether there is a ?safe? distance between California bay and coast live oak beyond...

  13. A multiscale landscape approach to predicting bird and moth rarity hotspots in a threatened pitch pine-scrub oak community

    Science.gov (United States)

    Joanna Grand; John Buonaccorsi; Samuel A. Cushman; Curtice R. Griffin; Maile C. Neel

    2004-01-01

    In the northeastern United States, pitch pine (Pinus rigida Mill.)-scrub oak (Quercus ilicifolia Wang.) communities are increasingly threatened by development and fire suppression, and prioritization of these habitats for conservation is of critical importance. As a basis for local conservation planning in a pitch pine-scrub oak community in southeastern Massachusetts...

  14. Characteristics of sites and trees affected by rapid white oak mortality as reported by forestry professionals in Missouri

    Science.gov (United States)

    Sharon E. Reed; James T. English; Rose-Marie Muzika; John M. Kabrick; Simeon. Wright

    2017-01-01

    A new syndrome was named rapid white oak mortality in 2011 to describe the rapid death of white oak trees (Quercus alba L.) within one growing season. A survey with 24 questions about stand and site characteristics, site history, and symptoms was distributed to forestry professionals to gather information about the new syndrome. Sixty-three reports...

  15. Establishing northern red oak on a degraded upland site in northeastern Pennsylvania: Influence of seedling pedigree and quality

    Science.gov (United States)

    Cornelia C. Pinchot; Thomas J. Hall; Scott E. Schlarbaum; Arnold M. Saxton; James. Bailey

    2017-01-01

    Enrichment plantings using large oak seedlings of regional sources may promote superior survival and growth compared to direct seeding or standard nursery seedling material. This study evaluated the survival and growth of planted 1-0 northern red oak (Quercus rubra L.) seedlings among 11 families and 3 seedling size classes (small, average, and...

  16. A cortiça como sonda ambiental de metais pesados: um serviço sócio-ambiental prestado por montados de sobro e sobreirais The cork as environmental probe of heavy metals: a socio- environmental service done by “montados” with cork oaks and cork oak stands (Quercus suber L.

    Directory of Open Access Journals (Sweden)

    J. Ponte-e-Sousa

    2007-01-01

    causa em cada camada da cortiça de sobreiros dispersos na área onde vegetam, poder obter-se uma estimativa dos teores médios desses metais nos locais frequentemente caracterizados pela presença daquela árvore, poderá vir a ser muito interessante para um conhecimento mais profundo desta realidade.The long term life of cork oak and the capacity that “amadia” cork has to build annual layers (highly separable allowed to create the hypothesis of correlation between the chemical marks made in each growing layer and the environmental characteristics of the place where the cork oak grows. This would allow to build space and time distribution series every nine years, about the characteristic in study. This is somewhat alike some dendrometric procedures, but these ones are much more aggressive. The objective of this work was to study lead (II in cork by voltammetry, because this method is well recognized as having competitive vantages over other known methods already used. The methodology adopted was: bark extraction, acid-hot digestion in closed recipient and voltammetric analytical signal search. The main conclusion is the possible association of this technique as another socioenvironmental service that “montado” can provide, in order to evaluate the quality of mediterranean basin continental areas with cork oak tree, regarding lead contamination.

  17. Impact of straw and rock-fragment mulches on soil moisture and early growth of holm oaks in a semiarid area

    Science.gov (United States)

    M. N. Jimenez; J. R. Pinto; M. A. Ripoll; A. Sanchez-Miranda; F. B. Navarro

    2017-01-01

    Planted seedlings and saplings usually exhibit low survival and growth rates under dry Mediterranean environments, especially late-successional species such as Quercus. In this work, we studied the effects of straw and rock fragment mulches on the establishment conditions of holm oak (Quercus ilex L. subsp. ballota (Def.) Samp.) in SE Spain. Soil moisture was...

  18. The Quercus pubescens relic forest on the Gennargentu Mountains (Sardinia, Italy

    Directory of Open Access Journals (Sweden)

    Citterio G

    2007-01-01

    Full Text Available The recent human impact has determined a strongly alteration of the Quercus pubescens forest on the Gennargentu Mountains in Sardinia. At the present, in this area the oak is represented by ancient single trees which can be considered relict and monumental individuals of the ancient forest. In this study, the space/time succession of oaks stands were analized in 1977 and 1997 years by GIS software and by multitemporal cartographic analyses. Some data about the stand structure are also reported.

  19. Comparison between the contribution of ellagitannins of new oak barrels and one-year-used barrels

    Directory of Open Access Journals (Sweden)

    Navarro María

    2016-01-01

    Full Text Available The influence of the botanical origin (French oak: Quercus petraea and American oak: Quercus alba, toasting level and if the barrel were new of previously used during one year have been studied. Results indicate that French oak released significant higher amounts of ellagitannins than American oak. Toasting level also exert a great influence. The higher the toasting level the lower the ellagitannin concentration in wines. Finally, the use during one year of the barrels drastically decreases the ellagitannin concentration in wines. Consequently, it can be concluded that the origin of oak, the toasting level and especially the previous use of the barrels have a very significant influence on the final ellagitannin concentration in wine, and probably on its sensory impact.

  20. Taxonomic and functional diversity of a Quercus pyrenaicaWilld. Rhizospheric microbiome in the Mediterranean mountains

    OpenAIRE

    Cobo-Díaz, JF; Fernández-González, AJ; Villadas, PJ; Toro, N; Tringe, SG; Fernández-López, M

    2017-01-01

    © 2017 by the authors. Altitude significantly affects vegetation growth and distribution, including the developmental stages of a forest. We used shotgun Illumina sequencing to analyze microbial community composition and functional potential in melojo-oak (Quercus pyrenaica Willd.) rhizospheric soil for three different development stages along an altitudinal gradient: (a) a low altitude, non-optimal site for forest maintenance; (b) an intermediate altitude, optimal site for a forest; and (c) ...

  1. Índices bursátiles en Europa

    OpenAIRE

    Martín González, Carolina

    2014-01-01

    La realización de este Trabajo Fin de Grado: "Índices bursátiles en Europa", tiene como objeto realizar un estudio descriptivo sobre 18 índices bursátiles de Europa, de los cuales 17 son índices de referencia del mercado de valores de sus respectivos países y un último índice -el Eurostoxx50- que engloba las principales compañías europeas. El periodo de análisis se extiende entre los años 2007 y 2013, periodo caracterizado por la reciente crisis económica y financiera. En él, se analizarán lo...

  2. Próba użycia insektycydów z grupy neonikotynoidów do ochrony żołędzi na plantacji nasiennej dębu szypułkowego (Quercus robur L.) w Nadleśnictwie Leżajsk

    National Research Council Canada - National Science Library

    Bystrowski, Cezary; Wójcik, Grzegorz

    2009-01-01

    Three neonicotinid insecticides: Apacz 50 WG, Confidor 200 SL and Mospilan 20 SP were used to control acorn pests Curculio spp. (Curculionidae: Coleoptera) and Cydia spp. (Tortricidae: Lepidoptera) in the oak (Quercus robur...

  3. ( Quercus spp. ) using random amplified polymorphic DNA (RAPD)

    African Journals Online (AJOL)

    Five species, including: Quercus robur, Quercus macranthera, Quercus infectoria, Quercus magnosquamata and Quercus libani were collected from Northwest forests of Iran and analyzed. Each tree was judged as a genuine type of each species according to the morphological structures. 10 RAPD primers reproducibly and ...

  4. Avian abundance and oak mistletoe survey data from the Willamette Valley, Oregon, 2013-2015

    Science.gov (United States)

    Pritchard, Kyle R.; Hagar, Joan; Shaw, David C.

    2017-01-01

    This dataset includes two spreadsheets: The "Avian_abundance_oak_mistletoe_bird_data" spreadsheet contains data regarding Oregon White Oak tree (Quercus garryana) measurements such as height, diameter and crown volume along with microhabitat data including number of mistletoe infections, number of cavities, amount of dead wood, amount of loose/missing bark, amount of poison oak, amount of bole cracks, and presence of woodpecker sign, bark-beetle sign, and fungal fruiting bodies. The "Avian_abundance_oak_mistletoe_surveys_data" spreadsheet contains bird survey observations including data, time, temperature, precipitation, bird species observations, age/sex, and behavioral observations.

  5. Relationships between advance oak regeneration and biotic and abiotic factors.

    Science.gov (United States)

    Fei, Songlin; Steiner, Kim C

    2008-07-01

    Relationships between advance regeneration of four tree species (red maple (Acer rubrum L.), white oak (Quercus alba L.), chestnut oak (Q. montana Willd.) and northern red oak (Q. rubra L.)) and biotic (non-tree vegetation and canopy composition) and abiotic (soil series and topographic variables) factors were investigated in 52, mature mixed-oak stands in the central Appalachians. Aggregate height was used as a composite measure of regeneration abundance. Analyses were carried out separately for two physiographic provinces. Associations with tree regeneration were found for all biotic and abiotic factors both in partial models and full models. Red maple was abundant on most of the sites, but high red maple abundance was commonly associated with wet north-facing slopes with little or no cover of mountain-laurel (Kalmia latifolia L.) and hay-scented fern (Dennstaedtia punctilobula (Michx.) Moore). Regeneration of the three oak species was greatly favored by the abundance of overstory trees of their own kind. White oak regeneration was most abundant on south-facing, gentle, lower slopes with soils in the Buchanan series. Chestnut oak regeneration was more common on south-facing, steep upper slopes with stony soils. There was a positive association between chestnut oak and huckleberry (Gaylussacia baccata (Wangh.) Koch) cover classes. Northern red oak was more abundant on north-facing wet sites with Hazleton soil, and was associated with low occurrence of mountain-laurel and hay-scented fern.

  6. The chamfer finish line: preclinical student performance using different bur designs.

    Science.gov (United States)

    Mansueto, Michael A; Abdulkarim, Hatem A; Thabet, Walid R; Haney, Stephan J

    2010-06-01

    The primary purposes of this investigation were to evaluate sophomore dental student performance in the production of a chamfer finish line using two diamond bur types-a round-ended bur and a torpedo-shaped bur-and to gain student feedback about their preferences for bur type. Fifty students took part in the study, each of whom prepared the buccal surfaces of two mandibular molar typodont teeth, producing chamfer finish lines. Students prepared both teeth in the same laboratory session and were randomly assigned to two groups that were required to prepare the first of the two molars with a specific bur type. The prepared chamfer finish lines were scored and the data analyzed using the Wilcoxon signed-rank test. Student performance was significantly better when the round-ended bur was used (p=0.005). Student feedback was collected with a survey that consisted of four questions and the opportunity to provide write-in comments. In response to the question "Overall, was one bur type better?" 58 percent of the students preferred the round-ended bur for creating a chamfer finish line. The most frequent write-in comment, made by twelve of the fifty students, criticized the torpedo-shaped bur for creating finish lines that were too shallow or too long.

  7. Effect of diamond bur cutting efficacy on dentin bond strengths of different bonding systems

    Directory of Open Access Journals (Sweden)

    Shirani F.

    2009-03-01

    Full Text Available "nBackground and Aim: As composite-dentin bond strength is affected by cavity preparation and the bond strength of composite resin to new and used bur prepared dentin has not yet been evaluated, this study evaluated the effects of cutting dentin with different cutting efficacy (new and used of burs on composite-dentin shear bond strength using self-etching primer bonding system and total etching bonding system. "nMaterials and Methods: Sixty caries free human 3rd molar were sectioned in occlosal surface to expose dentin, then polished with silicon carbide paper and randomly divided into four groups. Each group was prepared in a depth of 0.5mm of dentin, using new diamond bur, or used diamond bur. To change into a used bur, each new rough diamond bur had to work on bovine enamel for 30 minutes, under a load of 150g. Then, each group was bonded, using a total etch adhesive (single Bond or a self etch adhesive (clearfil SE Bond So there were 4 groups : 1-SE Bond, New bur; 2-SE Bond , used bur; 3-Single Bond , New bur ; 4-Single Bond, used bur. Similar composite capsules(Filtek Z250 were bonded to dentin surface and cured. specimens were stored in physiologic saline for 48h at 370 c , then put under shearing load to define composite - dentin shear bond strength. Results were interpreted via statistical analysis (T-test & two - way variance. "nResults: Shear bond strength of each group was as follows: 1-(27.3Mpa, 2-(33.5Mpa, 3-(16.9Mpa 4-(19.3Mpa. Statistical analysis proved that shear bond strength of used diamond bur prepared groups (2,4 was more than new diamond bur prepared ones (1,3. This statistical difference, specially, was seen between SE Bond groups (1,2 but not between single Bond groups (3,4. Also, shear bond strength of (SE Bond bonded groups (1,2 were more significantly than (single Bond bonded ones (3,4. "nConclusion: This study show that Bur cutting efficiency influences composite - dentin shear bond strength especially when the

  8. Changes in the Chemical Composition of Plum Distillate During Maturation with Oak Chips under Different Conditions

    Directory of Open Access Journals (Sweden)

    Maria Balcerek

    2017-01-01

    Full Text Available This study investigates the eff ect of ageing on the qualitative and quantitative composition of plum distillate in contact with oak wood chips. Maturation was performed with lightly toasted French oak (Quercus sessifl ora and Quercus robur chips or oak chips made from fragments of empty barrels that had been used for ageing cognac. The eff ects of oak chip dose, process temperature, ageing system (static or circulatory and ultrasound treatment were assessed. Maturation of plum distillate samples with oak chips resulted in higher levels of extractable organics (including tannins and colour changes, which were correlated with the type and dose of oak chips, and the conditions of maturation. The content of sugars such as glucose, xylose and arabinose also increased, depending on the conditions and type of oak chips. Degradation of lignin resulted in liberation of sinapaldehyde, syringaldehyde, coniferaldehyde and vanillin, with intensities depending on the applied parameters. In terms of volatiles, decreases in the concentration of higher alcohols and aliphatic aldehydes were observed in the majority of maturation experiments, while concentrations of furanic aldehydes increased depending on the type and dose of oak chips, as well as on the conditions of maturation. The quantities of esters such as ethyl acetate decreased in the majority of experimental variants, whereas concentrations of ethyl caproate, ethyl caprylate and ethyl caprate increased gradually. Some phenols and lactones were detected in all matured samples, with the lowest levels found in the samples aged with oak chips made from cognac barrels.

  9. Little Blue Prehistory: Archaeological Investigations at Blue Springs and Longview Lakes, Jackson County, Missouri. Volume 1

    Science.gov (United States)

    1989-01-01

    cottonwood Juglans nigra black walnut Carya spp. hickory Quercus alba white oak _. macrocarpa bur oak Q. stellate post oak Q. bicolor swamp white oak Q...coralberry, and other shrubs (Weaver 1960:63). The General Land Office survey recorded the presence of white oak, black oak, pin oak, walnut ( Juglans ...cordiformis) and black walnut ( Juglans nigra). Both are available in the fall and would be found in the vicinity of the site. The presence of these

  10. Ecological significance of seed desiccation sensitivity in Quercus ilex.

    Science.gov (United States)

    Joët, Thierry; Ourcival, Jean-Marc; Dussert, Stéphane

    2013-04-01

    Several widespread tree species of temperate forests, such as species of the genus Quercus, produce recalcitrant (desiccation-sensitive) seeds. However, the ecological significance of seed desiccation sensitivity in temperate regions is largely unknown. Do seeds of such species suffer from drying during the period when they remain on the soil, between shedding in autumn and the return of conditions required for germination in spring? To test this hypothesis, the Mediterranean holm oak (Quercus ilex) forest was used as a model system. The relationships between the climate in winter, the characteristics of microhabitats, acorn morphological traits, and the water status and viability of seeds after winter were then investigated in 42 woodlands sampled over the entire French distribution of the species. The percentages of germination and normal seedling development were tightly linked to the water content of seeds after the winter period, revealing that in situ desiccation is a major cause of mortality. The homogeneity of seed response to drying suggests that neither intraspecific genetic variation nor environmental conditions had a significant impact on the level of desiccation sensitivity of seeds. In contrast, the water and viability status of seeds at the time of collection were dramatically influenced by cumulative rainfall and maximum temperatures during winter. A significant effect of shade and of the type of soil cover was also evidenced. The findings establish that seed desiccation sensitivity is a key functional trait which may influence the success of recruitment in temperate recalcitrant seed species. Considering that most models of climate change predict changes in rainfall and temperature in the Mediterranean basin, the present work could help foresee changes in the distribution of Q. ilex and other oak species, and hence plant community alterations.

  11. Thinning to improve growth, bole quality, and forest health in an Inonotus hispidus-infected, red oak-sweetgum stand in the Mississippi Delta: 10-year results

    Science.gov (United States)

    James S. Meadows; Theodor D. Leininger; David Montwé; T. Evan Nebeker

    2013-01-01

    A 55-year-old red oak-sweetgum (Quercus spp.- Liquidambar styraciflua) stand on the Delta National Forest in western Mississippi was subjected to a combination of low thinning and improvement cutting in 1997. Special emphasis was placed on removing all red oaks infected with Inonotus hispidus, a canker decay...

  12. Influence of planting stocks on the survival and growth of Nuttall and cherrybark oak planted on lands damaged by Hurricane Katrina

    Science.gov (United States)

    Derek K. Alkire; James C. Rainer; Andrew B. Self; Andrew W. Ezell; Andrew J. Londo; Emily B. Schultz

    2013-01-01

    Bare-root, container, and root production method (RPMTM) seedlings of Nuttall oak (Quercus texana Buckley) and cherrybark oak (Q. pagoda Ell.) were planted on lands damaged by Hurricane Katrina in southern Mississippi to compare the height growth, groundline diameter (GLD) growth, and survival of the...

  13. Response of sun-grown and shade-grown northern red oak seedlings to outplanting in clearcuts and shelterwoods in North Alabama

    Science.gov (United States)

    Callie Jo Schweitzer; Emile S. Gardiner; David L. Loftis

    2006-01-01

    The primary objective of this study was to determine if greenhouse light environment would affect outplanting success for northern red oak (Quercus rubra L.) in clearcuts and shelterwoods. In 2002, northern red oak seedlings were grown from acorns under full-ambient (sun) and half-ambient (shade) light conditions in a greenhouse. Seedlings grown...

  14. Disking and mid- and understory removal following an above-average acorn crop in three mature oak forests in southern Indiana

    Science.gov (United States)

    Ronald A. Rathfon; Nathanael I. Lichti; Robert K. Swihart

    2008-01-01

    We disked using small-scale equipment in the understory of three mature upland oak (Quercus) forests in southern Indiana immediately following acorn dispersal in an aboveaverage seed crop year as a means of improving oak seedling establishment. Three different mid- and understory removal treatments were also applied to create favorable light...

  15. Host-induced genome alterations in Phytophthora ramorum, I. NA1 lineage on coast live oak in California, II. EU1 lineage on Chamaecyparis lawsoniana in UK

    Science.gov (United States)

    Takao Kasuga; Mai Bui; Elizabeth Bernhardt; Tedmund Swiecki; Kamyar Aram; Lien Bertier; Jennifer Yuzon; Liliana M. Cano; Joan Webber; Clive Brasier; Caroline Press; Niklaus Grünwald; David Rizzo; Matteo Garbelotto

    2017-01-01

    Rapid phenotypic diversification in clonal invasive populations is often observed, although the underlying genetic mechanisms remain elusive. Lineages of the sudden oak death pathogen Phytophthora ramorum are exclusively clonal, yet isolates of the NA1 lineage from oak (Quercus spp.) frequently exhibit...

  16. Mass loss and nutrient concentrations of buried wood as a function of organic matter removal, soil compaction, and vegetation control in a regenerating oak-pine forest

    Science.gov (United States)

    Felix Ponder; John M. Kabrick; Mary Beth Adams; Deborah S. Page-Dumroese; Marty F. Jurgensen

    2017-01-01

    Mass loss and nutrient concentrations of northern red oak (Quercus rubra) and white oak (Q. alba) wood stakes were measured 30 months after their burial in the upper 10 cm of soil in a regenerating forest after harvesting and soil disturbance. Disturbance treatments were two levels of organic matter (OM) removal (only...

  17. soil carbon pools within oak forest is endangered by global climate change in central mexico

    Science.gov (United States)

    García-Oliva, Felipe; Merino, Agustín; González-Rodriguez, Antonio; Chávez-Vergara, Bruno; Tapia-Torres, Yunuen; Oyama, Ken

    2016-04-01

    Forest soil represents the main C pool in terrestrial ecosystems. In particular, temperate forest ecosystems play an important role in the C budget among tropical countries, such as Mexico. For example, the temperate forest ecosystem contains higher C contents on average (295 Mg C ha-1) than the soil C associated with other ecosystems in Mexico (between 56 to 287 Mg C ha-1). At a regional scale, oak forest has the highest C content (460 Mg C ha-1) among the forest ecosystem in Michoacán State at Central Mexico. At the local scale, the soil C content is strongly affected by the composition of organic matter produced by the plant species. The oak species are very diverse in Mexico, distributed within two sections: Quercus sensu stricto and Lobatae. The oak species from Quercus s.s. section produced litterfall with lower concentrations of recalcitrant and thermostable compounds than oak species from Lobatae section, therefore the soil under the former species had higher microbial activity and nutrient availability than the soil under the later species. However, the forest fragment with higher amount of oak species from Quercus s.s. section increases the amount of soil C contents. Unfortunately, Quercus species distribution models for the central western region of Mexico predict a decrease of distribution area of the majority of oak species by the year 2080, as a consequence of higher temperatures and lower precipitation expected under climate change scenarios. Additionally to these scenarios, the remnant oak forest fragments suffer strong degradation due to uncontrolled wood extraction and deforestation. For this reason, the conservation of oak forest fragments is a priority to mitigate the greenhouse gases emission to the atmosphere. In order to enhance the protection of these forest fragments it is required that the society identify the ecosystem services that are provided by these forest fragments.

  18. Natural hybridization and hybrid zones between Quercus crassifolia and Quercus crassipes (Fagaceae) in Mexico: morphological and molecular evidence.

    Science.gov (United States)

    Tovar-Sánchez, Efraín; Oyama, Ken

    2004-09-01

    Hybrid zones provide interesting systems to study genetic and ecological interaction between different species. The correct identification of hybrids is necessary to understand the evolutionary process involved in hybridization. An oak species complex occurring in Mexico formed by two parental species, Quercus crassifolia H. & B. and Q. crassipes H. & B., and their putative hybrid species, Q. dysophylla, was analyzed with molecular markers (random amplified polymorphic DNA [RAPDs]) and morphological tools in seven hybrid zones (10 trees per taxa in each hybrid zone) and two pure sites for each parental species (20 trees per site). We tested whether geographic proximity of hybrid plants to the allopatric site of a parental species increases its morphological and genetic similarity with its parent. Seventeen morphological traits were measured in 8700 leaves from 290 trees. Total DNA of 250 individuals was analyzed with six diagnostic RAPD primers. Quercus crassifolia differed significantly from Q. crassipes in all the examined characters. Molecular markers and morphological characters were highly coincident and support the hypothesis of hybridization in this complex, although both species remain distinct in mixed stands. Clusters and a hybrid index (for molecular and morphological data) showed that individuals from the same parental species were more similar among themselves than to putative hybrids, indicating occasional hybridization with segregation in hybrid types or backcrossing to parents. Evidence does not indicate a unidirectional pattern of gene flow.

  19. Comparative study of the cutting efficiency and working life of carbide burs.

    Science.gov (United States)

    Di Cristofaro, Rebecca G Riera; Giner, Lluis; Mayoral, Juan Ricardo

    2013-07-01

    The aim of this study was to establish the wear and cutting efficiency of tungsten carbide burs from different manufacturers by performing cutting tests with machinable glass ceramic. Cutting tests were performed with 70 tungsten carbide burs from seven manufacturers: (A) Coltene/Whaledent, (B) CEI, (C) Meisinger, (D) Axis, (E) Komet, (F) Kerr, (G) Edenta. All groups were examined under scanning electron microscope (SEM) before and after the cutting efficiency test for similarities and differences. A specially designed cutting device was used. An electric handpiece was operated at 200,000 rpm with a 120 ml/min coolant water supply rate. The burs were tested under a 165 g constant load using 3 mm wide Macor ceramic as substrate. For each bur the cutting procedure involved a total of five cuts of 3 minutes on every cut, with a total cutting time for each bur of 15 minutes. Data were analyzed using one-way ANOVA at 95.0% confidence level. Significant differences (p cutting rates of the different groups. Groups A and B showed the highest cutting rates. Higher cutting rates were associated with a longer bur lifespan. SEM photomicrographs of the burs and substrates revealed significant changes on the surfaces after the cutting process. The morphology characteristics of tungsten carbide burs are related to their effectiveness. The group that presented the worst working life also showed substantial wear on its surface according to the results of SEM. © 2013 by the American College of Prosthodontists.

  20. Degradation in the fatigue strength of dentin by diamond bur preparations: Importance of cutting direction.

    Science.gov (United States)

    Majd, B; Majd, H; Porter, J A; Romberg, E; Arola, D

    2016-01-01

    The objectives of this investigation were to evaluate the degradation in fatigue strength of dentin by diamond bur preparations and to identify the importance of cutting direction. Three groups of coronal dentin specimens were prepared from unrestored third molars, including a flaw free "control," and two groups that received a diamond bur cutting treatment performed parallel or perpendicular to the specimen length. The specimens were subjected to static or cyclic flexural loading to failure and the results were compared with data for carbide bur cutting. Under static loading diamond bur cutting resulted in significantly lower flexure strength (p ≤ 0.05) than the control for both cutting directions (from 154 to ∼124 MPa). However, there was no significant difference in the strength between the control and carbide bur treated specimens. Similarly, the fatigue strength of the diamond bur treated specimens was significantly lower (p ≤ 0.0001) than that of the control for both cutting directions. Cutting in the perpendicular direction resulted in nearly 60% reduction to the endurance limit (from 44 to 19 MPa). Based on the results, diamond bur cutting of cavity preparations causes a reduction in the fatigue strength of dentin, regardless of the cutting direction. To maintain the durability of dentin, cavity preparations introduced using diamond burs must be performed with appropriate cutting direction and followed by a finishing pass. © 2014 Wiley Periodicals, Inc.

  1. Stimulation of Armillaria rhizomorph growth by oak root fungi

    Directory of Open Access Journals (Sweden)

    Hanna Kwaśna

    2014-08-01

    Full Text Available Thirty one different genera of fungi were isolated from the wood of roots of 5O·year·old oak (Quercus robur. The most frequently isolated fungi were: Mycelium radicis atrovirens alpha (MRAA, Clonostachys sp. and Penicillium daleae, Beauveria bassiana, Clonostachys sp., Cryplosporiopsis rodicicolo, Geotrichum candidum, Mortierella vinacea, MRAA, P. daleae, P. janczewskii P. spinulosum, Sporothrix schenckii and Tolypocladium niveum significantly enhanced Armillaria mellea rhizomorph initiation and growth from oak branch segments in vitro. The biggest stimulation effect was noticed when the dematiaceous hyphomycetes, e.g. MRAA, P. dimorphospora and S. schenckii were studied.

  2. Comparison of water-use efficiency of seedlings from two sympatric oak species: genotype × environment interactions

    OpenAIRE

    Ponton, Stéphane; Dupouey, Jean-Luc; Breda, Nathalie; Dreyer, Erwin

    2002-01-01

    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 (δ13C) and on gas exchange measurements (ratio of net CO2 assimilation rate to stomatal conductance (A/gsw)). In addition, genotype × environment interactions were tested by sub...

  3. Evolution of ellagitannins in Spanish, French, and American oak woods during natural seasoning and toasting.

    Science.gov (United States)

    Cadahía, E; Varea, S; Muñoz, L; Fernández De Simón, B; García-Vallejo, M C

    2001-08-01

    The evolution of tannins in Spanish oak heartwood of Quercus robur L., Quercus petraea Liebl.,Quercus pyrenaica Wild., and Quercus faginea Lam. was studied in relation to the processing of wood in barrel cooperage. Their evolution was compared with that of French oak of Q. robur (Limousin, France) and Q. petraea (Allier, France) and American oak of Quercus alba L. (Missouri), which are habitually used in cooperage. Two stages of process were researched: the seasoning of woods during 3 years in natural conditions and toasting. Total phenol and total ellagitannin contents and optical density at 420 nm of wood extracts were determined. The ellagitannins roburins A-E, grandinin, vescalagin, and castalagin were identified and quantified by HPLC, and the molecular weight distribution of ellagitannins was calculated by GPC. During the seasoning process the different ellagitannin concentrations decreased according to the duration of this process and in the same way as those in French and American woods. The toasting process also had an important influence on the ellagitannin composition of wood. Roburins A-E, grandinin, vescalagin, and castalagin decreased during this process in the Spanish wood species, in the same proportion as in the French and American ones. Also, the seasoning and toasting processes lead to qualitative variations in the structure of ellagitannins, especially in the molecular weight distribution, as was evidenced by GPC analysis of their acetylated derivatives.

  4. Micro-morphometric assessment of titanium plasma-sprayed coating removal using burs for the treatment of peri-implant disease.

    Science.gov (United States)

    Rimondini, L; Cicognani Simoncini, F; Carrassi, A

    2000-04-01

    This study evaluated, in vitro, the effectiveness of diamond and carbide burs, and bur sequences to remove the plasma-sprayed titanium coating from IMZ fixture surfaces. Fifteen polishing procedures were tested. They included the use of 12, 16, 30 bladed carbide burs or bevered carbide burs and 30, 15, 8 microns mean-particles-size diamond burs. The treated surfaces were evaluated with profilometer and SEM. Worn burs and titanium debris produced by the grinding were observed with SEM. All procedures produce smoother surfaces than baseline plasma-sprayed surfaces for both Ra and Rz(DIN) parameters (P < 0.001). A roughening effect of the 8 microns mean-grit diamond bur and 30 bladed burs were noted. The single carbide burs produce polished surfaces affected by waviness. Waviness was minimized by sequence or diamond bur use. The carbide bur blades were variously damaged after their use. In contrast, the grit of diamond burs was observed to be clogged by titanium debris whose amount seemed to be inversely related to the diamond mean particle size. Debris produced by diamond burs was granular whereas that produced by carbide bladed burs showed needle or flake morphology. In conclusion, the most effective titanium plasma sprayed removal were obtained by 30 microns and 15 microns mean-particle-size diamond burs, i.e. 30 microns plus 15 microns diamond burs and carbide 12 plus 16 bladed burs used in sequence.

  5. First report of the European oak borer, Agrilus sulcicollis (Coleoptera: Buprestidae), in the United States

    Science.gov (United States)

    Robert A. Haack; Toby R. Petrice; James E. Zablotny

    2009-01-01

    Agrilus sulcicollis Lacordaire was first reported in North America from Ontario, Canada in 2008; specimens were collected in the field on red oak (Quercus rubra L.), on sticky traps, and also found in insect collections that dated from 1995. After hearing of this discovery in Ontario, unidentified Agrilus...

  6. Product recovery from tree grade 1 northern red oak on Menominee tribal lands

    Science.gov (United States)

    John P. Dwyer; Daniel C. Dey

    2007-01-01

    Since 1854 the Menominee Tribal people have practiced some level of forest management on their lands. In April of 2000, Menominee Tribal Enterprises (MTE) forestry staff along with federal, state, and university researchers began a comprehensive study of value in northern red oak (Quercus rubra L.). One of the objectives of this study was to relate...

  7. Ethanol attracts scolytid beetles to Phytophthora ramorum cankers on coast live oak [Abstract

    Science.gov (United States)

    Rick G. Kelsey; Maia Beh; Dave Shaw; Daniel K. Manter

    2013-01-01

    Successful infection of coast live oak (Quercus agrifolia Née) stems by Phytophthora ramorum results in the formation of a canker visible initially at the bark surface by the release of a dark red to black colored exudate referred to as "bleeding." Bark and ambrosia beetles are often attracted to diseased trees within...

  8. Survival and growth of planted northern red oak in northern West Virginia

    Science.gov (United States)

    Charles A. McNeel; David M. Hix; Edwin C. Townsend

    1993-01-01

    The survival and growth of northern red oak (Quercus rubra L.) seedlings planted beneath a shelterwood in northern West Virginia were evaluated one year after planting. The use of 1.5 m (5 ft) tall TUBEX tree shelters on planted seedlings was also examined. The study was conducted on both excellent and good sites (site indices of 27 m (89 ft) and 22...

  9. Oak, fire, and global change in the eastern USA: what might the future hold?

    Science.gov (United States)

    James M. Vose; Katherine Elliott

    2016-01-01

    The pace of environmental and socioeconomic change over the past 100 years has been rapid. Changes in fire regimes, climate, and land use have shaped the structure and function of most forest ecosystems, including oak (Quercus spp. L.) forests in the eastern United States.New stressors such as air pollution and invasive species have contributed to...

  10. Shading and root-shoot relations in saplings of silver birch, pedunculate oak and beech

    NARCIS (Netherlands)

    Hees, van A.F.M.; Clerkx, A.P.P.M.

    2003-01-01

    Silver birch (Betula pendula Roth), pedunculate oak (Quercus robur L.) and beech (Fagus sylvatica L.) can regenerate successfully under a canopy of Scots pine (Pinus sylvestris L.). Shading reduces plant growth and modifies plant form, two related aspects. This study focuses on the effects of

  11. Large Drought-Induced Variations in Oak Leaf Volatile Organic Compound Emissions during PINOT NOIR 2012

    Science.gov (United States)

    Leaf-level isoprene and monoterpene emissions were collected and analyzed from five of the most abundant oak (Quercus) species in Central Missouri’s Ozarks Region in 2012 during PINOT NOIR (Particle Investigations at a Northern Ozarks Tower ‐ NOx, Oxidants, Isoprene Research). Ju...

  12. Blue oak plant communities of southern San Luis Obispo and northern Santa Barbara Counties, California

    Science.gov (United States)

    Mark I. Borchert; Nancy D. Cunha; Patricia C. Krosse; Marcee L. Lawrence

    1993-01-01

    An ecological classification system has been developed for the Pacific Southwest Region of the Forest Service. As part of that classification effort, blue oak (Quercus douglasii) woodlands and forests of southern San Luis Obispo and northern Santa Barbara Counties in Los Padres National Forest were classified into I3 plant communities using...

  13. Adaptability of black walnut, black cherry, and Northern red oak to Northern California

    Science.gov (United States)

    Philip M. McDonald

    1987-01-01

    When planted in sheltered sites in northern California, only 49% of black walnut (Juglans nigra L.) and 58% of black cherry (Prunus serotina Ehrh.) survived for 15 years, and 20% of northern red oak (Quercus rubra L.) survived for 10 years. The black walnut trees averaged 0.6 inches diameter at breast...

  14. Field response of red oak, pin cherry and black cherry seedlings to a light gradient

    Science.gov (United States)

    M.R. Roberts

    1991-01-01

    The objective of this study is to determine the relationship between light conditions and the growth of natural seedlings of red oak (Quercus rubra L.), pin cherry (Prunus pensylvanica L.) and black cherry (P. serotina Ehrh.) growing under a range of canopy densities in northwestern Pennsylvania.

  15. Effects of Understory Burning in a Mesic Mixed-Oak Forest of the Southern Appalachians

    Science.gov (United States)

    Katherine J. Elliott; James M. Vose; Barton D. Clinton; Jennifer D. Knoepp

    2004-01-01

    Information is lacking on ecosystem effects of understory burning in mesic mixed-oak (Quercus spp.) forests of the southern Appalachians. Native Americans used periodic fires in these forests for driving game and opening the forest. In April 1998, we conducted a low- to moderate-intensity fire in a cove­hardwood forest in the Nantahala National...

  16. Differentiating defects in red oak lumber by discriminant analysis using color, shape, and density

    Science.gov (United States)

    B. H. Bond; D. Earl Kline; Philip A. Araman

    2002-01-01

    Defect color, shape, and density measures aid in the differentiation of knots, bark pockets, stain/mineral streak, and clearwood in red oak, (Quercus rubra). Various color, shape, and density measures were extracted for defects present in color and X-ray images captured using a color line scan camera and an X-ray line scan detector. Analysis of variance was used to...

  17. Oak mast production and animal impacts on acorn survival in the central hardwoods

    Science.gov (United States)

    Kenneth F. Kellner; Jeffery K. Riegel; Nathanael I. Lichti; Robert K. Swihart

    2013-01-01

    As part of the Hardwood Ecosystem Experiment we measured mast production in white (Quercus alba) and black (Q. velutina) oak, and quantified the impacts of seed predators on acorn survival over a 3-year period. Specifically, we measured the proportion of acorns of each species infested with weevils (Curculio spp...

  18. Elevated CO2 compensates for water stress in northern red oak

    Science.gov (United States)

    Patricia T. Tomlinson; Paul D. Anderson

    1996-01-01

    Global climate change models predict decreased rainfall in association with elevated CO2 in the western Lakes States region. Currently, the western edge of northern red oak (Quercus rubra L.) distribution coincides with the most xeric conditions of its ecological range. Decreased rainfall and water availability could alter...

  19. Approaches to restoration of oak forests on farmed lowlands of the Mississippi River and its tributaries

    Science.gov (United States)

    Emile S. Gardiner; Daniel C. Dey; John A. Stanturf; Brian Roy. Lockhart

    2010-01-01

    The lowlands associated with the Mississippi River and its tributaries historically supported extensive broadleaf forests that were particularly rich in oak (Quercus spp.) species. Beginning in the 1700s, deforestation for agriculture substantially reduced the extent of the original forest, and fragmented the remainder into small parcels. More...

  20. Root morphology and growth of bare-root seedlings of Oregon white oak

    Science.gov (United States)

    Peter J. Gould; Constance A. Harrington

    2009-01-01

    Root morphology and stem size were evaluated as predictors of height and basal-area growth (measured at groundline) of 1-1 Oregon white oak (Quercus garryana Dougl. ex Hook.) seedlings planted in raised beds with or without an additional irrigation treatment. Seedlings were classified into three root classes based on a visual assessment of the...

  1. Seasonal trends in response to inoculation of coast live oak with Phytophthora ramorum

    Science.gov (United States)

    Richard S. Dodd; Daniel Hüberli; Tamar Y. Harnik; Brenda O' Dell; Matteo Garbelotto

    2006-01-01

    We developed a branch cutting inoculation method to provide a controlled system for studying variation in response to inoculation of coast live oak (Quercus agrifolia) with Phytophthora ramorum. This method has advantages over inoculations of trees in the field, in containing the inoculum and in allowing high levels of replication...

  2. Influence of kinetin on in vitro rooting and survival of banj oak ...

    African Journals Online (AJOL)

    A study concerning the influence of cytokinins on shoot regeneration by using different stem segments derived from in vitro raised seedlings and their subsequent rooting was conducted in banj oak (Quercus leucotrichophora L.). Cytokinins play an important role in shoot regeneration and their multiplication. In the present ...

  3. Determining fire history from old white pine stumps in an oak-pine forest

    Science.gov (United States)

    Richard P. Guyette; Daniel C. Dey; Chris McDonell

    1995-01-01

    Fire scars on stumps of white pine (Pinus strobus L.) in a red oak (Quercus rubra L.) white pine forest near Bracebridge, Ontario, were dated using dendrochronological methods. A chronological record of fires that caused basal scarring is preserved in the remnant white pine stumps, which were estimated to be up to 135 years old...

  4. Patterns of northern red oak growth and mortality in western Pennsylvania

    Science.gov (United States)

    J. R. McClenahen; R. J. Hutnik; D. D. Davis

    1997-01-01

    This study evaluates the extent and cause(s) of an observed decline of northern red oak (Quercus rubra L.) on a 50-km portion of a major anticlinal ridge in west central Pennsylvania, and illustrates an approach for evaluating tree declines. Long term annual observations of forest health revealed the onset of crown dieback in 1983, chiefly among red...

  5. Relationship between precipitation and tree mortality levels in coastal California forests infested with sudden oak death

    Science.gov (United States)

    Brent Oblinger; Zachary Heath; Jeffrey Moore; Lisa Fischer

    2013-01-01

    Phytophthora ramorum has caused extensive oak (Quercus) and tanoak (Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh) mortality in portions of the central and north coasts of California. In conjunction with stream and terrestrial surveys, aerial detection surveys have played a...

  6. Potential of ultrasonic pulse velocity for evaluating the dimensional stability of oak and chestnut wood

    Science.gov (United States)

    Turker Dundar; Xiping Wang; Nusret As; Erkan Avci

    2016-01-01

    The objective of this study was to examine the potential of ultrasonic velocity as a rapid and nondestructive method to predict the dimensional stability of oak (Quercus petraea (Mattuschka) Lieblein) and chestnut (Castanea sativa Mill.) that are commonly used in flooring industry. Ultrasonic velocity, specific gravity, and radial, tangential and volumetric shrinkages...

  7. Residual stand damage from crop tree release felling operations in white oak stands

    Science.gov (United States)

    Jeffrey W. Stringer; Gary W. Miller; H. Clay Smith

    1988-01-01

    This study was conducted at the University of Kentucky's Robinson Forest located in Breathitt, Knott, and Perry counties in eastern Kentucky. Three treatments including two levels of croptree release, leaving 20 and 34 crop trees per acre, and a control treatment were replicated 4 times and randomly distributed among l.2 white oak (Quercus alba...

  8. Long-term above-ground biomass production in a red oak-pecan agroforestry system

    Science.gov (United States)

    Agroforestry systems have widely been recognized for their potential to foster long-term carbon sequestration in woody perennials. This study aims to determine the above-ground biomass in a 16-year-old red oak (Quercus rubra) - pecan (Carya illinoinensis) silvopastoral planting (141 and 53 trees ha-...

  9. Chloroplast DNA variation of oaks in western Central Europe and genetic consequences of human influences

    NARCIS (Netherlands)

    König, A.O.; Ziegenhagen, B.; Dam, van B.C.; Csaikl, U.M.; Coart, E.; Degen, B.; Burg, K.; Vries, de S.M.G.; Petit, R.J.

    2002-01-01

    Oak chloroplast DNA (cpDNA) variation was studied in a grid-based inventory in western Central Europe, including Belgium, The Netherlands, Luxembourg, Germany, the Czech Republic, and the northern parts of Upper and Lower Austria. A total of 2155 trees representing 426 populations of Quercus robur

  10. The Vallarta Botanical Garden's advancements in conserving the diversity of native Mexican oaks and magnolias

    Science.gov (United States)

    N.A. Gerlowski; M.A. Muñiz-Castro

    2017-01-01

    Mexico is both an oak (Quercus) biodiversity hotspot (over 160 described species) and the western hemisphere's leader in magnolia (Magnolia) diversity (36 described species). In the face of myriad threats to these groups, including climate change, habitat loss/fragmentation, overharvesting, and plant pests/pathogens, the...

  11. Advanced Oak Seedling Development as Influenced by Shelterwood Treatments, Competition Control, Deer Fencing, and Prescribed Fire

    Science.gov (United States)

    Gary W. Miller; Patrick H. Brose; Kurt W. Gottschalk

    2017-01-01

    Advanced northern red oak (Quercus rubra) seedlings in an 85-year-old forest located in north-central Pennsylvania were observed for 10 years after manipulation of available sunlight by shelterwood treatments, reduction of interfering plants by broadcast herbicides and/or a single prescribed fire, and reduction of deer damage by fencing. Twenty-...

  12. White oak epicotyl emergence and 1-0 seedling growth from surgically altered germinating acorns

    Science.gov (United States)

    Shi-Jean Susana Sung; Paul P. Kormanik; Stanley J. Zarnoch

    2010-01-01

    Open-pollinated white oak (Quercus alba L.) acorns were collected and stored at 4 °C in November 2004. Three days before sowing in early December, we treated germinating acorns in five ways: no surgery (C); one half of the radical cut off (HR); whole radicle cut off (WR); one cotyledonary petiole severed (OP); and both cotyledonary petioles severed,...

  13. The effect of storage temperature and duration on northern red oak acorn viability and vigour

    Science.gov (United States)

    Thomas L. Noland; Andree E. Morneault; Daniel C. Dey; Dave. Deugo

    2013-01-01

    Three separate collections of Ontario sources of northern red oak (Quercus rubra L.) acorns were made to determine the effects of long-term cold storage at +2°C, -1°C, and -2°C on their viability and vigour. We measured acorn moisture content, percent germination during storage, speed of germination and total germination...

  14. Phytosociological description of Quercus petraea forest stands with Chamaecytisus hirsutus and Erica carnea in the Vipavska brda (southwestern Slovenia)

    OpenAIRE

    Dakskobler, Igor

    2014-01-01

    We conducted a phytosociological study of Quercus petraea stands, whose herb layer is dominated by Erica carnea in the flysch hills of Vipavska brda and on the margins of the Vrhe plateau (southwestern Slovenia). We have determined that they are a long-term degradation stage on beech forest sites from the association Seslerio autumnalis-Fagetum. Based on comparisons with similar sessile oak stands from associations Melampyro vulgati-Quercetum petraeae, Seslerio autumnalis-Quercetum petraeae a...

  15. Pathogenicity of Armillaria Isolates Inoculated on Five Quercus Species at Different Watering Regimes

    Directory of Open Access Journals (Sweden)

    R. Metaliaj

    2006-04-01

    Full Text Available One of three fungal isolates of Armillaria mellea (Vahl: Fr. P. Kummer, A. gallica Marxm. et Romagn. and A. tabescens (Scop.: Fr. Emel. was inoculated on 1,440 three-year-old potted seedlings of five Quercus species (Q. cerris L., Q. ilex L., Q. pubescens Willd., Q. robur L. and Q. trojana Webb. grown at different watering regimes in a greenhouse. Inoculum was represented by a piece of an oak branch colonised with the fungus (or sterile, as a control, which was attached to the unwounded main root of each oak seedling. During the growing season, differences in water availability among seedlings were measured monthly using minimum water potential assessments on noninoculated seedlings receiving an equal amount of water. Although all three Armillaria isolates induced infection, the A. mellea isolate was most pathogenic in all cases, while the A. gallica isolate showed a statistically equal degree of pathogenicity only on the least watered seedlings. Of the Quercus species, Q. ilex showed the greatest number of infected seedlings, Q. robur the smallest. Reducing the water supply to potted oak seedlings could be a useful indicator for detecting differences in pathogenicity between Armillaria species.

  16. Environmental stress on establishment and growth in Fagus sylvatica L. and Quercus robur L. seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Loef, Magnus [Swedish Univ. of Agricultural Sciences, Alnarp (Sweden). Southern Swedish Forest Research Centre

    1999-04-01

    In this thesis, the growth response to different environmental stresses in beech (Fagus sylvatica L.) and oak (Quercus robur L.) seedlings was studied in relation to site preparation and use of shelterwood. Growth and survival were compared between beech, oak and Norway spruce (Picea abies L. Karst.) seedlings under similar conditions. In a field experiment, with herbicide, herbicide plus fertilization and mowing as treatments, interference from herbaceous vegetation was mainly below ground. Furthermore, soil water is probably the growth factor of greatest importance for establishing beech and oak on fertile sites in southern Sweden. In pot experiments carried out in a climatic chamber both previous and current-year drought influenced growth in beech in the current year, and it was concluded that previous environmental conditions must be taken into consideration to understand growth of seedlings in the current year. Episodic drought resulted in long recovery periods in beech transpiration after rewatering, but also after-effects on transpiration. Thus, short periods of drought may still influence growth afterwards when the soil is rewetted. In field experiments, soil disturbance by patch scarification, mixing of humus with mineral soil and deep cultivation of soil did not increase growth in seedlings compared to untreated soil or where chemical vegetation control was carried out. When, vegetation was efficiently controlled by using a shelterwood of Norway spruce, survival of beech, oak and Norway spruce seedlings planted under the shelterwood trees was high. There was no difference in growth between beech and oak seedlings under the shelterwood. On an open site, oak had a shorter period of transplanting shock, higher growth during interference from vegetation and deeper roots than beech. Thus, beech need more intense site preparation for successful establishment. Herbivory by pine weevil was lower on beech and oak than on Norway spruce. Less efforts are therefore

  17. Acorns of introduced Quercus rubra are neglected by European Jay but spread by mice

    Directory of Open Access Journals (Sweden)

    Judith Bieberich

    2016-12-01

    Full Text Available Northern Red Oak (Quercus rubra L.; native in North America is regarded as an invasive species in Central Europe, where it is the most common non-indigenous broad-leafed tree species in forestry. The species’ impact on native ecosystems and thus its future management are discussed controversially. Because dispersal is an important step in an invasion process, we studied whether European Jays (Garrulus glandarius L. and mice, both main dispersers of native oaks in Europe, mediate the dispersal of Q. rubra seeds. Morphological characteristics of Q. rubra and native Q. robur L. acorns were quantified according to their implications for dispersal. We tested experimentally whether and to what extent mice and jays collect acorns of both oak species and if their behavior depends on choice options (dual choice vs. no-choice. Acorns were offered on feeding platforms, controlled by scouting cameras. Results showed that Q. rubra acorns have a thicker pericarp, a rounder shape and a higher dry weight compared to acorns of Q. robur. In the behavioral assays jays avoided acorns of Q. rubra if they were offered together with those of Q. robur (dual choice as well as when Q. rubra acorns were offered alone (no-choice. This selection behavior could be caused by the differences in morphological traits observed between the acorns of the two species. In contrast to jays, mice took acorns of both oak species likewise indicating that seed morphology does not affect the attractiveness of Red Oak acorns for rodents. In conclusion, Quercus rubra is collected by animals in Central Europe to a considerable amount but dispersal should be restricted to moderate distances mediated by mice, leading mainly to stabilizing and increasing existing populations rather than founding of new ones.

  18. Fossil oak galls preserve ancient multitrophic interactions.

    Science.gov (United States)

    Stone, Graham N; van der Ham, Raymond W J M; Brewer, Jan G

    2008-10-07

    Trace fossils of insect feeding have contributed substantially to our understanding of the evolution of insect-plant interactions. The most complex phenotypes of herbivory are galls, whose diagnostic morphologies often allow the identification of the gall inducer. Although fossil insect-induced galls over 300Myr old are known, most are two-dimensional impressions lacking adequate morphological detail either for the precise identification of the causer or for detection of the communities of specialist parasitoids and inquilines inhabiting modern plant galls. Here, we describe the first evidence for such multitrophic associations in Pleistocene fossil galls from the Eemian interglacial (130000-115000 years ago) of The Netherlands. The exceptionally well-preserved fossils can be attributed to extant species of Andricus gallwasps (Hymenoptera: Cynipidae) galling oaks (Quercus), and provide the first fossil evidence of gall attack by herbivorous inquiline gallwasps. Furthermore, phylogenetic placement of one fossil in a lineage showing obligate host plant alternation implies the presence of a second oak species, Quercus cerris, currently unknown from Eemian fossils in northwestern Europe. This contrasts with the southern European native range of Q. cerris in the current interglacial and suggests that gallwasp invasions following human planting of Q. cerris in northern Europe may represent a return to preglacial distribution limits.

  19. Changes in low molecular weight phenolic compounds in Spanish, French, and American oak woods during natural seasoning and toasting.

    Science.gov (United States)

    Cadahía, E; Muñoz, L; Fernández de Simón, B; García-Vallejo, M C

    2001-04-01

    The evolution of low molecular weight polyphenols in Spanish oak heartwood of Quercus robur,Quercus petraea, Quercus pyrenaica, and Quercus faginea was studied by HPLC, in relation to the processing of wood in barrel cooperage. The polyphenolic composition of Spanish woods subjected to natural seasoning for 3 years and to the toasting process was studied in relation to those of French oak of Q. robur (Limousin) and Q. petraea (Allier) and American oak of Q. alba (Missouri), which are habitually used in cooperage. The concentrations of benzoic and cinnamic acids and aldehydes of Spanish woods increased during seasoning depending on the duration of this process and in the same way as those of French and American woods. The process having the main influence on the phenolic composition of wood was the toasting. It led to high increases in the concentration of phenolic aldehydes and acids, especially cinnamic aldehydes (sinapic and coniferylic aldehydes), followed by benzoic aldehydes (syringaldehyde and vanillin) and benzoic acids (syringic and vanillic acids). This polyphenolic composition in Spanish oak species evolved during toasting as in French and American oak, but quantitative differences were found, which were especially important in American species with respect to the others.

  20. CLIMATIC FACTORS AND ESTABLISHMENT OF QUERCUS ILEX - COMMUNITIES IN TRIESTE PROVINCE (NE ITALY

    Directory of Open Access Journals (Sweden)

    A. FURLANETTO

    2004-01-01

    Full Text Available In the coastal area called "Cernizza" (near Duino. ca 15 km NW from Trieste, at an altitude between 0 and 40 m. is located a wood vegetation complex characterized by Quercus ilex and Carpinus orientalis. The bedrocks of this site is carbonatic. This wood vegetation does not occur in other sites or the Trieste province, where deciduous oak woods (Q. pubescells, Q. petraea s.1. are dominant both on arenaceus and on carbonatic rocks. Other Quercus ilex communities are occurring only as scrubs on the calcareous coastal cliffs characterized by primitive lithosoils. In order to detect if this wood community might be an expression of the c1imate dominating this particular zone, some Duino's c1imatic data, relative lo a record period of 9 years. have been compared with the Trieste's ones. The analysed parameters were the following: air temperature. rainfall, evaporation. wind speed and relative humidity. From the comparison of these paramenters it emerged that the Duino's climate is more humid than the Trieste's one. Only in springtime Duino is less rainy than Trieste according lo the analysis of the monthly mean values of precipitation. From the ecophysiological point of view, a study of the seasonal changes of the root hydraulic conductance in some forest trees (Nardini el al .. 1998 has pointed out the superiority of Quercus ilex compared to Quercus pubescens, as regards the competitive ability of the seedlings during the spring. For this reason, the smaller spring rainfall could explain the occurrence of Quercus ilex stands not only in the neighbourhood of Duino but also at the beginning of the large valleys characterized by S•N direction in the South Eastern Alps.

  1. CLIMATIC FACTORS AND ESTABLISHMENT OF QUERCUS ILEX - COMMUNITIES IN TRIESTE PROVINCE (NE ITALY

    Directory of Open Access Journals (Sweden)

    M. CODOGNO

    2004-05-01

    Full Text Available In the coastal area called "Cernizza" (near Duino. ca 15 km NW from Trieste, at an altitude between 0 and 40 m. is located a wood vegetation complex characterized by Quercus ilex and Carpinus orientalis. The bedrocks of this site is carbonatic. This wood vegetation does not occur in other sites or the Trieste province, where deciduous oak woods (Q. pubescells, Q. petraea s.1. are dominant both on arenaceus and on carbonatic rocks. Other Quercus ilex communities are occurring only as scrubs on the calcareous coastal cliffs characterized by primitive lithosoils. In order to detect if this wood community might be an expression of the c1imate dominating this particular zone, some Duino's c1imatic data, relative lo a record period of 9 years. have been compared with the Trieste's ones. The analysed parameters were the following: air temperature. rainfall, evaporation. wind speed and relative humidity. From the comparison of these paramenters it emerged that the Duino's climate is more humid than the Trieste's one. Only in springtime Duino is less rainy than Trieste according lo the analysis of the monthly mean values of precipitation. From the ecophysiological point of view, a study of the seasonal changes of the root hydraulic conductance in some forest trees (Nardini el al .. 1998 has pointed out the superiority of Quercus ilex compared to Quercus pubescens, as regards the competitive ability of the seedlings during the spring. For this reason, the smaller spring rainfall could explain the occurrence of Quercus ilex stands not only in the neighbourhood of Duino but also at the beginning of the large valleys characterized by S•N direction in the South Eastern Alps.

  2. Pre-dispersal strategies by Quercus schottkyana to mitigate the effects of weevil infestation of acorns

    OpenAIRE

    Ke Xia; William L. Harrower; Roy Turkington; Hong-Yu Tan; Zhe-Kun Zhou

    2016-01-01

    We investigated how pre-dispersal strategies may mitigate the effects of weevil infestation of acorns in a population of Quercus schottkyana, a dominant oak in Asian evergreen broad-leaved forests, and assess if weevil infestation contributes to low seedling recruitment. We counted the number of acorns produced, daily from the end of August to mid-late November for 9 years from 2006?2014. We also recorded the rate of acorn infestation by weevils and acorn germination rates of weekly collectio...

  3. Word-wide meta-analysis of Quercus forests ectomycorrhizal fungal diversity reveals southwestern Mexico as a hotspot.

    Science.gov (United States)

    García-Guzmán, Olimpia Mariana; Garibay-Orijel, Roberto; Hernández, Edith; Arellano-Torres, Elsa; Oyama, Ken

    2017-11-01

    Quercus is the most diverse genus of ectomycorrhizal (ECM) host plants; it is distributed in the Northern and Southern Hemispheres, from temperate to tropical regions. However, their ECM communities have been scarcely studied in comparison to those of conifers. The objectives of this study were to determine the richness of ECM fungi associated with oak forests in the Cuitzeo basin in southwestern Mexico; and to determine the level of richness, potential endemism and species similarity among ECM fungal communities associated with natural oak forests worldwide through a meta-analysis. The ITS DNA sequences of ECM root tips from 14 studies were included in the meta-analysis. In total, 1065 species of ECM fungi have been documented worldwide; however, 812 species have been only found at one site. Oak forests in Europe contain 416 species, Mexico 307, USA 285, and China 151. Species with wider distributions are Sebacinaceae sp. SH197130, Amanita subjunquillea, Cenococcum geophilum, Cortinarius decipiens, Russula hortensis, R. risigallina, R. subrubescens, Sebacinaceae sp. SH214607, Tomentella ferruginea, and T. lapida. The meta-analysis revealed (1) that Mexico is not only a hotspot for oak species but also for their ECM mycobionts. (2) There is a particularly high diversity of ECM Pezizales in oak seasonal forests from western USA to southwestern Mexico. (3) The oak forests in southwestern Mexico have the largest number of potential endemic species. (4) Globally, there is a high turnover of ECM fungal species associated with oaks, which indicates high levels of alpha and beta diversity in these communities.

  4. Laboratory analysis of dental sections made with commercial tungsten carbide burs coated with HFCVD diamond

    Energy Technology Data Exchange (ETDEWEB)

    Maass, F [Departamento de Fisica, Universidad de Antofagasta, Av. Angamos 601, Antofagasta (Chile); Aguilera, Y [Departamento de Ingenieria Industrial, Universidad de Antofagasta, Av. Angamos 601, Antofagasta (Chile); Avaria, J [Departamento de OdontologIa, Universidad de Antofagasta, Av. Angamos 601, Antofagasta (Chile)], E-mail: fdmaass@uantof.cl

    2008-11-01

    The objective of this study was to determine the cutting power of diamond burs obtained by the HFCVD deposition process. Diamond was deposited on the active part of each of a series of 10 commonly used Tungsten Carbide (WC) commercial burs. The quality of the section was compared with sections made by commonly used commercial burs, employing fresh human molars and a standard device [1]. Both burs and sections were analysed by using SEM and EDX techniques. The quality and tension of the deposited diamond coatings were analyzed by Raman Spectroscopy. The optimal thickness of the diamond coating which provided the best durability and finish of the sections was determined by comparative observations of results.

  5. Effects of flapless bur decortications on movement velocity of dogs′ teeth

    Directory of Open Access Journals (Sweden)

    Seyed Mohammadreza Safavi

    2012-01-01

    Conclusion: (1 Corticotomy facilitated orthodontic tooth movement is achievable with flapless bur decortication technique. (2 Velocity of tooth movement decreases in later stages of treatment due to maturation of newly formed bone at decortication sites.

  6. Surface roughness and wettability of enamel and dentine surfaces prepared with different dental burs.

    Science.gov (United States)

    Al-Omari, W M; Mitchell, C A; Cunningham, J L

    2001-07-01

    The aim of dental adhesive restorations is to produce a long lasting union between the restoration and the tooth structure. This bond depends on many variables including the geometry of the preparation and the type of bonding agent or luting cement. It is therefore suggested that the topography of the tooth surface may influence the wettability and the bonding quality of adhesive systems. This study measured the surface roughness and wettability of enamel and dentine after preparation with different dental burs. The mesial and distal surfaces of 15 extracted sound human premolar teeth were prepared with a tungsten carbide crown bur, a diamond bur and a tungsten carbide finishing bur and finished in enamel or dentin, respectively. The prepared surfaces were analysed with a surface profilometer and scanning electron microscopy (SEM). The contact angle of distilled water on each of the prepared surfaces was used as the measure of wettability. The differences in average surface roughness (Ra) were significant between the rotary instrument groups, as revealed by a two-way ANOVA test. No differences were detected between enamel and dentine surfaces prepared with the same type of dental bur. The smoothest surfaces were those completed with tungsten carbide finishing burs. The diamond bur preparations were intermediate in the roughness assessment and the tungsten carbide crown burs gave the roughest surfaces. There were no significant differences in the contact angle measurements for the various groups. It was concluded that the surface roughness of enamel and dentine prepared by different rotary instruments had no significant influence on the wettability of distilled water on these surfaces.

  7. Fracture resistance of zirconia-based all-ceramic crowns after bur adjustment.

    Science.gov (United States)

    Rues, Stefan; Schwindling, Franz S; Meyer, Andre; Rammelsberg, Peter; Schmitter, Marc

    2017-08-01

    Intra-oral grinding is often required to optimize occlusion of all-ceramic restorations. The effect of burs of different grit size on the fracture resistance of veneered zirconia crowns was investigated in this study. Forty-eight standardized zirconia copings were produced. The ceramic veneer was designed with a positive ellipsoidal defect on the palatal aspect of the crowns. To simulate adjustment of dental restorations by burs, this palatal defect was removed by use of three different diamond-coated burs with grit sizes 46, 107, or 151 μm (fine, medium, or coarse, respectively). Each different grit size of bur was used to grind 16 crowns. All crowns were then polished and surface roughness was measured. Half of the specimens underwent thermomechanical aging (10,000 thermocycles between 6.5°C and 60°C) and 1.2 million cycles of chewing simulation (F = 108 N). A linear regression model was computed to test the effect of aging and grinding grit size at a level of significance of α = 0.05. Fracture loads increased with decreasing grit size. Grit size and aging had a significant effect on the fracture resistance of the crowns. Use of fine and coarse burs for intra-oral adjustments resulted in different fracture resistance of veneered zirconia crowns. Coarse burs should be avoided in the final stage of grinding before polishing. © 2017 Eur J Oral Sci.

  8. Applying Hotspot Detection Methods in Forestry: A Case Study of Chestnut Oak Regeneration

    Directory of Open Access Journals (Sweden)

    Songlin Fei

    2010-01-01

    Full Text Available Hotspot detection has been widely adopted in health sciences for disease surveillance, but rarely in natural resource disciplines. In this paper, two spatial scan statistics (SaTScan and ClusterSeer and a nonspatial classification and regression trees method were evaluated as techniques for identifying chestnut oak (Quercus Montana regeneration hotspots among 50 mixed-oak stands in the central Appalachian region of the eastern United States. Hotspots defined by the three methods had a moderate level of conformity and revealed similar chestnut oak regeneration site affinity. Chestnut oak regeneration hotspots were positively associated with the abundance of chestnut oak trees in the overstory and a moderate cover of heather species (Vaccinium and Gaylussacia spp. but were negatively associated with the abundance of hayscented fern (Dennstaedtia punctilobula and mountain laurel (Kalmia latiforia. In general, hotspot detection is a viable tool for assisting natural resource managers with identifying areas possessing significantly high or low tree regeneration.

  9. CHANGES IN VOLATILE COMPOSITION AND SENSORY PROPERTIES OF VUGAVA WINES AGED IN CROATIA OAK BARRELS

    Directory of Open Access Journals (Sweden)

    Stanka HERJAVEC

    2001-09-01

    Full Text Available Vugava musts were fermented in medium-toasted Croatian barrique barrels (225 L made from Quercus petrea and Q. robur oak wood. The oak species used in this research infl uenced the specifi c change of the aroma structure of Vugava wines. During the age period the increase in the concentration of cis and trans oaklactons, guaiacol, eugenol, furfural and 5-methylfurfural was noted. Wines fermented and aged in Q. petrea barrels have higher concentrations of most volatile phenols compared to wines from Q. robur oak wood. From the organoleptic point of view this study suggested that fermentation and on the lees ageing production method in Croatian oak barrels positively infl uenced the quality of Vugava wines where best results were achieved by use of Q. petrea oak wood.

  10. Densities of Agrilus auroguttatus and Other Borers in California and Arizona Oaks

    Directory of Open Access Journals (Sweden)

    Laurel J. Haavik

    2014-03-01

    Full Text Available We investigated within-tree population density of a new invasive species in southern California, the goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae, with respect to host species and the community of other borers present. We measured emergence hole densities of A. auroguttatus and other borers on the lower stem (bole of naïve oaks at 18 sites in southern California and on co-evolved oaks at seven sites in southeastern Arizona. We sampled recently dead oaks in an effort to quantify the community of primary and secondary borers associated with mortality—species that were likely to interact with A. auroguttatus. Red oaks (Section Lobatae produced greater densities of A. auroguttatus than white oaks (Section Quercus. On red oaks, A. auroguttatus significantly outnumbered native borers in California (mean ± SE of 9.6 ± 0.7 versus 4.5 ± 0.6 emergence holes per 0.09 m2 of bark surface, yet this was not the case in Arizona (0.9 ± 0.2 versus 1.1 ± 0.2 emergence holes per 0.09 m2. In California, a species that is taxonomically intermediate between red and white oaks, Quercus chrysolepis (Section Protobalanus, exhibited similar A. auroguttatus emergence densities compared with a co-occurring red oak, Q. kelloggii. As an invasive species in California, A. auroguttatus may affect the community of native borers (mainly Buprestidae and Cerambycidae that feed on the lower boles of oaks, although it remains unclear whether its impact will be positive or negative.

  11. Effect of hybridization of the Quercus crassifolia x Quercus crassipes complex on the community structure of endophagous insects.

    Science.gov (United States)

    Tovar-Sánchez, Efraín; Oyama, Ken

    2006-04-01

    In a previous study, we showed that the geographic proximity of hybrid plants to the allopatric areas of parental species increases their morphological and genetic similarity with them. In the present work, we explored whether the endophagous fauna of hybrid plants show the same pattern. We studied the canopy species richness, diversity and composition of leaf-mining moths (Lepidoptera: Tischeridae, Citheraniidae) and gall-forming wasps (Hymenoptera: Cynipidae) associated with two species of red oaks (Quercus crassifolia and Quercus crassipes) and their interspecific hybrid (Quercusxdysophylla Benth pro sp.) in seven hybrid zones in central Mexico, during four seasons in 2 years. The study was conducted on 194 oak trees with known genetic status [identified by leaf morphology and molecular markers (random amplified polymorphic DNAs)], and the results indicate a bidirectional pattern of gene flow. Hybrid plants supported intermediate levels of infestation of gall-forming and leaf-mining insects compared to their putative parental species. The infestation level of leaf-mining insects varied significantly following the pattern: Q. crassifolia>hybrids>Q. crassipes, whereas the gall-forming insects showed an inverse pattern. A negative and significant relationship was found between these two types of insect guilds in each host taxa, when the infestation percentage was evaluated. It was found that 31.5% (n=11) of the endophagous insects were specific to Q. crassipes, 22.9% (n=8) to Q. crassifolia, and 8.6% (n=3) to hybrid individuals. The hybrid bridge hypothesis was supported in the case of 25.7% (n=9) of insects, which suggests that the presence of a hybrid intermediary plant may favor a host herbivore shift from one plant species to another. Greater genetic diversity in a hybrid zone is associated with greater diversity in the endophagous community. The geographic proximity of hybrid plants to the allopatric site of a parental species increases their similarity in

  12. Sympatric parallel diversification of major oak clades in the Americas and the origins of Mexican species diversity.

    Science.gov (United States)

    Hipp, Andrew L; Manos, Paul S; González-Rodríguez, Antonio; Hahn, Marlene; Kaproth, Matthew; McVay, John D; Avalos, Susana Valencia; Cavender-Bares, Jeannine

    2017-09-18

    Oaks (Quercus, Fagaceae) are the dominant tree genus of North America in species number and biomass, and Mexico is a global center of oak diversity. Understanding the origins of oak diversity is key to understanding biodiversity of northern temperate forests. A phylogenetic study of biogeography, niche evolution and diversification patterns in Quercus was performed using 300 samples, 146 species. Next-generation sequencing data were generated using the restriction-site associated DNA (RAD-seq) method. A time-calibrated maximum likelihood phylogeny was inferred and analyzed with bioclimatic, soils, and leaf habit data to reconstruct the biogeographic and evolutionary history of the American oaks. Our highly resolved phylogeny demonstrates sympatric parallel diversification in climatic niche, leaf habit, and diversification rates. The two major American oak clades arose in what is now the boreal zone and radiated, in parallel, from eastern North America into Mexico and Central America. Oaks adapted rapidly to niche transitions. The Mexican oaks are particularly numerous, not because Mexico is a center of origin, but because of high rates of lineage diversification associated with high rates of evolution along moisture gradients and between the evergreen and deciduous leaf habits. Sympatric parallel diversification in the oaks has shaped the diversity of North American forests. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  13. Pathology of oak-wisteria powdery mildew.

    Science.gov (United States)

    Cook, Roger T A; Denton, Jenny O; Denton, Geoffrey

    2015-08-01

    The relationship between oak and wisteria powdery mildew, the reason artificial infection of Wisteria sinensis was difficult, and the identity of the pathogen were investigated. Inoculations of detached leaves of Quercus robur with Erysiphe alphitoides from either W. sinensis or Q. robur were successful. Wisteria floribunda was completely and W. sinensis partially resistant. Isolates from wisteria and oak had similar pathogenicities and matching DNA profiles and hence not separable into formae speciales. Instead, oak mildew now includes wisteria and possibly Sorbaria as hosts. On non-host Brassica and cellulose acetate, conidial germ tube development ceased after formation of terminal appressoria. Only Q. robur supported visible lesions. W. sinensis supported fewer colony forming hyphae (CFH) per conidium and smaller hyphal appressoria. Failure to form visible lesions was due to prevention or termination of CFH and not to inhibition of conidial germination or to a host's hypersensitive reaction. Absorption of antifungal compounds via appressoria from maturing host tissue is discussed. The pathogen's DNA ITS region indicated an identification of Erysiphe alphitoides sensu lato, since some isolates did not completely match E. alphitoides sensu stricto. To rapidly indicate susceptibility, a microscopic examination of young leaves 48 h post inoculation is recommended. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  14. After 25 years, what does the Pennsylvania Regeneration Study tell us about oak/hickory forests under stress?

    Science.gov (United States)

    William H. McWilliams; James A. Westfall; Patrick H. Brose; Shawn L. Lehman; Randall S. Morin; Todd E. Ristau; Alejandro A. Royo; Susan L. Stout

    2017-01-01

    The Pennsylvania Regeneration Study was initiated in 1989 because of concerns about a long history of stress on oak/hickory (Quercus/Carya) forests from herbivory and other factors. The study, which addresses the need for landscape-level information about regeneration quality and abundance, comprises a suite of regeneration indicator measurements...

  15. Mortality, scarring, and growth in an oak woodland following prescribed fire and commercial thinning in the Ozark Highlands

    Science.gov (United States)

    C.S. Kinkead; M.C. Stambaugh; J.M. Kabrick

    2017-01-01

    Oak-dominated (Quercus Spp.) woodlands are commonly thinned and burned in the Ozark Highlands to prevent canopy closure and regenerate desired species, despite a lack of information regarding tree mortality, scarring, and growth in residual stands. Our study compared stand- and tree-level responses after two prescribed burns across four treatments...

  16. Biology and management of the western gray squirrel and Oregon white oak woodlands: with emphasis on the Puget Trough.

    Science.gov (United States)

    L.A. Ryan; A.B. Carey

    1995-01-01

    The western gray squirrel (Sciurus griseus Ord, 1818) has been accorded "threatened species" status by the state of Washington. populations are small, scattered, and declining primarily due to the loss and fragmentation of suitable habitat. Western gray squirrels are closely associated with Oregon white oak (Quercus garryana...

  17. Effect of directed-spray glyphosate applications on survival and growth of planted oaks after three growing seasons

    Science.gov (United States)

    Andrew B. Self; Andrew W. Ezell; Josh L. Moree; Rory O. Thornton

    2013-01-01

    Thousands of acres of oak (Quercus spp.) plantations are established across the South annually. Survival and growth of these plantings have been less than desirable. Several techniques have been utilized in attempts to achieve improved success in these areas. One such technique that has been recommended is the application of directed-spray herbicide...

  18. Field performance of Nuttall Oak on former agricultural fields: Initial effects of nursery source and competition control

    Science.gov (United States)

    Emile S. Gardiner; K. Francis Salifu; Douglass F. Jacobs; George Hernandez; Ronald P. Overton

    2007-01-01

    Nuttall oak (Quercus nuttallii Palm.) seedlings raised at state nurseries in Mississippi, Louisiana, and Arkansas were morphologically different in height, root collar diameter, fresh mass, number of first-order lateral roots, root volume, and height-to-root collar diameter ratio. When outplanted on afforestation sites in the Lower Mississippi...

  19. Growth and mortality of pin oak and pecan reforestation in a constructed wetland: analysis with management implications

    Science.gov (United States)

    D.E. Henderson; P. Botch; J. Cussimanio; D. Ryan; J. Kabrick; D. Dey

    2009-01-01

    Pin oak (Quercus palustris Muenchh.) and pecan (Carya illinoensis (Wangenh.) K. Koch) trees were planted on reforestation plots at Four Rivers Conservation Area in west-central Missouri. The study was conducted to determine survival and growth rates of the two species under different production methods and environmental variables....

  20. Molecular and morphological characterization of Xiphinema chambersi population from live oak in Jekyll Island, Georgia, with comments on morphometric variations

    Science.gov (United States)

    Zafar A. Handoo; Lynn K. Carta; Andrea M. Skantar; Sergei A. Subbotin; Stephen Fraedrich

    2016-01-01

    A population of Xiphinema chambersi from the root zone around live oak (Quercus virginiana Mill.) trees on Jekyll Island, GA, is described using both morphological and molecular tools and compared with descriptions of type specimens. Initially, because of a few morphological differences, this nematode was thought to represent an undescribed species. However, on further...

  1. Understory Vegetation 3 Years after Implementing Uneven-Aged Silviculture in a Shortleaf Pine-Oak Stand

    Science.gov (United States)

    Michael G. Shelton; Paul A. Murphy

    1997-01-01

    The effects of retaining overstory hardwoods on understory vegetation were determined after implementing uneven-aged silviculture usingsingle-tree selection in a shortleaf pine-oak stand (Pinus echinata Mill. and Quercus spp.) in the Ouachita Mountains. Treatments were the following hardwood basal areas (square feet per acre) and...

  2. The Temporal and Spatial Distribution of Filbert Weevil Infested Acorns in an Oak Woodland in Marin County, California

    Science.gov (United States)

    Vernard R. Lewis

    1991-01-01

    Two-hundred shoots contained within randomly selected locations from each of thirty-six coast live oak, Quercus agrifolia, trees were sampled to determine the abundance and spatial distribution of acorns infested by the filbert weevil, Curculio occidentis in northern California during 1989. The seasonal abundance of infested acorns...

  3. Stem quality of oak in 15-year-old stands: influence of species within harvesting treatment and fencing

    Science.gov (United States)

    Kurt W. Gottschalk

    1997-01-01

    The effect of harvesting treatment, fencing, and species on the stem quality of oak (Quercus spp.) was evaluated in mixed-hardwood stands on the Allegheny Plateau in central Pennsylvania. The regeneration harvests included commercial clearcut that removed most stems ≥ 15 cm dbh and a clearcut with timber stand improvement (TSI) that removed...

  4. Mexican spotted owl home range and habitat use in pine-oak forest: Implications for forest management

    Science.gov (United States)

    Joseph L. Ganey; William M. Block; Jeffrey S. Jenness; Randolph A. Wilson

    1998-01-01

    To better understand the habitat relationships of the Mexican spotted owl (Strix occidentalis lucida), and how such relationships might influence forest management, we studied home-range and habitat use of radio-marked owls in ponderosa pine (Pinus ponderosa) Gambel oak (Quercus gambelii) forest. Annual home-range size (95% adaptive-kernel estimate) averaged 895 ha...

  5. Effect of diamond burs on process and damage involving in vitro dental resurfacing of a restorative porcelain

    Science.gov (United States)

    Yin, Ling; Han, Yi-Gang; Song, Xiao-Fei; Wang, Hui

    2007-09-01

    This work reports on the effect of diamond burs with coarse, medium and fine grit sizes and nickel or chromium coatings on in vitro dental resurfacing of a restorative porcelain. Process parameters such as tangential and normal forces, surface roughness, surface damage and morphology were studied as a function of removal rate using the different burs. At the lower removal rate, the differences for both the tangential and the normal forces were not significant among the coarse, medium and fine burs. However, when the porcelain was removed at the higher removal rate, both the tangential and the normal forces were markedly higher using the fine bur than those using the medium and coarse burs. Surface roughness values in terms of arithmetic mean and maximum roughness decreased significantly with a decrease in diamond grit size. The scale of surface damage in the form of brittle fracture decreased, and more transitions from brittle removal to ductile flow were observed when using finer grit diamond burs. In a comparison of the diamond bur topographies before and after dental finishing, it was found that minimal wear occurred on the nickel-coated coarse diamond bur, while minor abrasive wear occurred on the nickel-coated medium and chromium-coated fine burs.

  6. Effect of diamond burs on process and damage involving in vitro dental resurfacing of a restorative porcelain

    Energy Technology Data Exchange (ETDEWEB)

    Yin Ling [School of Mechanical Engineering, Tianjin University, Tianjin 300072 (China); Han Yigang [School of Mechanical Engineering, Tianjin University, Tianjin 300072 (China); Song Xiaofei [School of Mechanical Engineering, Tianjin University, Tianjin 300072 (China); Wang Hui [Analysis and Measurement Center, Tianjin University, Tianjin 300072 (China)

    2007-09-07

    This work reports on the effect of diamond burs with coarse, medium and fine grit sizes and nickel or chromium coatings on in vitro dental resurfacing of a restorative porcelain. Process parameters such as tangential and normal forces, surface roughness, surface damage and morphology were studied as a function of removal rate using the different burs. At the lower removal rate, the differences for both the tangential and the normal forces were not significant among the coarse, medium and fine burs. However, when the porcelain was removed at the higher removal rate, both the tangential and the normal forces were markedly higher using the fine bur than those using the medium and coarse burs. Surface roughness values in terms of arithmetic mean and maximum roughness decreased significantly with a decrease in diamond grit size. The scale of surface damage in the form of brittle fracture decreased, and more transitions from brittle removal to ductile flow were observed when using finer grit diamond burs. In a comparison of the diamond bur topographies before and after dental finishing, it was found that minimal wear occurred on the nickel-coated coarse diamond bur, while minor abrasive wear occurred on the nickel-coated medium and chromium-coated fine burs.

  7. Estudio cariológico de Quercus humboldtti Bonpl Caryological study of Quercus humboldtii Bonpl

    Directory of Open Access Journals (Sweden)

    Alvarado de Coral Cecilia

    1989-12-01

    Full Text Available Se comprobó que la especie del roble Ouercus humboldtii Bonpl. tiene 2 n= 24 cromosomas, al igual que la mayoría de las especies estudiadas de Quercus. Utilizando pretratamiento y tinción con orceina lactopropiónica fue posible obtener el cariotipo e ideograma.Using lactopropionic orceine for a previus tintion we obtained the Caryotype and ideogram of Quercus humboldtii Bonpl. and we observed that it has 2 n = 24 chromosomes as most studied species of Quercus do.

  8. Oaks and Environmental Education

    Science.gov (United States)

    Kay Antunez de Mayolo

    1991-01-01

    A number of educational projects which focus on youth awareness and involvement with California oaks have been developed during the last five years. Primarily used in urban areas where oak populations have declined, many of these programs promote seedling propagation, tree planting and help to develop student understanding of environmental issues involving oaks while...

  9. Interception loss, throughfall and stemflow chemistry in pine and oak forests in northeastern Mexico.

    Science.gov (United States)

    Cantú Silva, I; González Rodríguez, H

    2001-08-01

    Interception loss, gross precipitation, throughfall and stemflow solution chemistry beneath pine (Pinus pseudostrobus Lindl.), oak (Quercus sp.) and pine-oak natural forest canopies in northeastern Mexico were measured. Coefficients of variation for throughfall were 12% in pine and oak canopies and 17% in the mixed pine-oak canopy. The variability of stemflow averaged 66, 126 and 73% for pine, oak and the mixed pine-oak canopies, respectively. Linear regression analysis of net versus gross precipitation for the three canopies showed highly significant correlations (r = 0.974-0.984). Total precipitation during the experimental period was 974 mm and estimated interception loss was 19.2, 13.6 and 23% for the pine, oak and pine-oak canopies, respectively. Stemflow did not occur following rainfall events of less than 4 mm and, in all canopies, stemflow represented a minimal proportion of gross precipitation (0.60, 0.50 and 0.03% for pine, oak and pine-oak, respectively). Throughfall pH in pine (6.2), oak (6.3) and pine-oak (6.3) canopies was significantly more acidic than gross precipitation (6.6). Stemflow pH ranged from 3.7 (pine) to 6.0 (oak). The pine-oak canopy registered the highest throughfall and stemflow electrical conductivities, 104 and 188 microS cm(-1), respectively. Net nutrient leaching of K, Mg, Na, Fe, Mn and Zn was significantly higher from the pine-oak canopy than from the pure pine and oak canopies. Mean depositions of Ca and Cu in throughfall behaved similarly among the three types of canopies. A greater proportion of Zn in gross precipitation was absorbed by the oak canopy than by the pine and pine-oak canopies. Enrichment factors beneath the pine-oak canopy relative to gross precipitation varied from 1.2 to 3.2 for macro-nutrients (Ca, K, Mg and Na) and from 1.4 to 3.1 for micro-nutrients (Cu, Fe, Mn and Zn). Stemflow depositions of Ca, K, Mg and Cu were higher in the pine-oak canopy, whereas stemflow depositions of Na, Fe, Mn and Zn were higher

  10. (Quercus spp.) using random amplified polymorphic DNA (RAPD)

    African Journals Online (AJOL)

    ajl10

    2012-06-05

    Jun 5, 2012 ... Quercus is one of the most important woody genera of the Northern hemisphere and considered as one of the main forest tree species in Iran. In this study, genetic relationships in the genus Quercus, using random amplified polymorphic DNA (RAPD) was examined. Five species, including: Quercus robur,.

  11. The origin of Ceratocystis fagacearum, the oak wilt fungus.

    Science.gov (United States)

    Juzwik, Jennifer; Harrington, Thomas C; MacDonald, William L; Appel, David N

    2008-01-01

    The oak wilt pathogen, Ceratocystis fagacearum, may be another example of a damaging, exotic species in forest ecosystems in the United States. Though C. fagacearum has received much research attention, the origin of the fungus is unknown. The pathogen may have been endemic at a low incidence until increased disturbances, changes in land use, and forest management created conditions favorable for disease epidemics. The host genus Quercus contains some relatively resistant species native to the United States, further supporting the hypothesis that the pathogen is native in origin. However, there are also many common, highly susceptible Quercus species--a characteristic typical of introduced pathogens. Most convincingly, studies have shown that the known populations of C. fagacearum have experienced a severe genetic bottleneck that can only be explained by a single introduction. The weight of evidence indicates that C. fagacearum is an introduced pathogen, with possible origins in Central or South America, or Mexico.

  12. The Castanea sativa bur as a new potential ingredient for nutraceutical and cosmetic outcomes: preliminary studies.

    Science.gov (United States)

    Pinto, Diana; Rodrigues, Francisca; Braga, Nair; Santos, Joana; Pimentel, Filipa B; Palmeira-de-Oliveira, Ana; Oliveira, M Beatriz P P

    2017-01-25

    Chestnuts are a common food product in Mediterranean countries, being recognized also for their beneficial effects on human health. Nevertheless, during processing, these fruits generate a large amount of food by-products, such as shells and burs. In the present work, the macronutrient composition, vitamin E profile and amino acid content of the burs were determined in samples from three different Portuguese regions (Minho, Trás-os-Montes and Beira-Alta). The nutritional composition was similar for all samples, being characterised by a high moisture content and low fat amounts. All essential amino acids were present in considerable amounts. Concerning vitamin E, the predominant vitamer was α-tocopherol for the Minho and Beira-Alta samples. The total phenolic compounds were quantified, and the antioxidant activity evaluated in different extracts using two biochemical assays (DPPH˙ and FRAP). All bur extracts showed a high total phenolic content, the highest obtained being that for the Beira-Alta samples. The chestnut bur from Minho showed the highest antioxidant activity in both assays. This study aims to demonstrate the potential of the Castanea sativa bur as a cosmetic and nutraceutical ingredient.

  13. Large-scale patterns of Quercus ilex, Quercus suber, and Quercus pyrenaica regeneration in central-western Spain

    DEFF Research Database (Denmark)

    Plieninger, Tobias; Rolo, Víctor; Moreno, Gerardo

    2010-01-01

    In Central-Western Spain, forests and woodlands composed of Quercus sp. support outstanding levels of biodiversity, but there is increasing concern about their long-term persistence due to a lack of regeneration. We hypothesize that this regenerative lack is operating on a large geographic scale;...

  14. Comparison of cutting efficiency with different diamond burs and water flow rates in cutting lithium disilicate glass ceramic.

    Science.gov (United States)

    Siegel, Sharon C; Patel, Tejas

    2016-10-01

    This study compared different diamond burs and different water flow rates on the cutting efficiency of sectioning through lithium disilicate glass ceramic. The authors used a standardized cutting regimen with 4 brands of diamond burs to section through lithium disilicate glass ceramic blocks. Twelve diamonds of each brand cut through the blocks in randomized order. In the first part of the study, the authors recorded sectioning rates in millimeters per minute for each diamond bur as a measure of cutting efficiency. In the second part of the study, the authors compared sectioning rates using only 1 brand of diamond bur, with 3 different water flow rates. The authors averaged and compared cutting rates of each brand of diamond bur and the cutting rates for each flow rate using an analysis of variance and determined the differences with a Tukey honest significant difference test. One diamond bur cut significantly slower than the other 3, and one diamond bur cut significantly faster than 2 of the others. The diamond bur cutting efficiency through lithium disilicate glass ceramic with a 20 mL/min water flow rate was significantly higher than 15 mL/min. There are differences in cutting efficiency between diamond burs when sectioning lithium disilicate glass ceramic. Use a minimum of 20 mL/min of water coolant flow when sectioning lithium disilicate glass ceramic with dental diamond burs to maximize cutting efficiency. Recommendations for specific diamond burs with a coarse grit and water flow rate of 20 mL/min can be made when removing or adjusting restorations made from lithium disilicate glass ceramic. Copyright © 2016 American Dental Association. Published by Elsevier Inc. All rights reserved.

  15. Growth, ectomycorrhization and biochemical parameters of Quercus ...

    African Journals Online (AJOL)

    The survival of the seedlings under these drought conditions was due to two strategies: osmotic adjustment through soluble sugars and proteins accumulations in leaves and an increase in carbon discrimination which enhances the water use efficiency (WUE). Keywords: Quercus suber, growth, drought, ectomycorrhization, ...

  16. Plant regeneration by somatic embryogenesis from cultured immature embryos of oak (Querem robur L.) and linden (Tilia cordata Mill.).

    Science.gov (United States)

    Chalupa, V

    1990-11-01

    Embryogenic cultures and somatic embryos were obtained from immature zygotic embryos of oak (Quercus robur L.) cultured on a modified MS medium and WPM containing BAP (1 mg·l(-1)) and GA3 (1 mg·l(-1)) or BAP and IBA. Germination and conversion of oak somatic embryos into plantlets was achieved on WPM containing a reduced concentration of cytokinin. Linden (Tilia cordata Mill.) somatic embryos developed in embryogenic tissues initiated from immature zygotic embryos cultured on a modified MS medium supplemented with 2,4-D (0.3-2.0 mg·l(-1)). Germination of linden somatic embryos and plantlet formation occurred on MS medium containing a low concentration of IBA. Oak and linden plantlets produced from somatic embryos were successfully established in soil. Somatic embryos and plantlets were also regenerated from embryogenic cultures of Quercus petraea and Tilia platyphyllos.

  17. Informe sobre la relación entre consumo, morosidad y ciclos bursátiles.

    OpenAIRE

    Ariño, Miguel A.; Coello de Portugal, Maria

    1999-01-01

    En este estudio se pretende establecer posibles relaciones entre el consumo, la morosidad y los ciclos bursátiles. En la primera parte se expone qué variables permiten medir el consumo, qué variables se pueden utilizar como índices de morosidad, y qué variables sirven para medir los ciclos bursátiles. La segunda parte mostrará las relaciones que existen entre estos tres tipos de variables. Al final de la segunda parte, un cuadro resume todas estas relaciones.

  18. A comparison of carbon sequestration potential and photosynthetic efficiency in evergreen and deciduous oaks growing in contrasting environments in the Southwest UK

    OpenAIRE

    Carne, Demelza Jane

    2013-01-01

    Global climate change is predicted to alter the weather patterns around the world, as climatic zones shift, forest carbon sequestration projects (e.g. the UK woodland carbon code) need to take into account the specific requirements of planted species. In the UK, oaks are an important charismatic group of trees favoured in recent planting programmes. The English oak (Quercus robur L.), has poor water conservation, but is a major component of natural forests in lowland UK. On the other hand, Ho...

  19. Chemical evaluation, antioxidant capacity, and consumer acceptance of several oak infusions.

    Science.gov (United States)

    Rocha-Guzmán, Nuria Elizabeth; Medina-Medrano, Jose Roberto; Gallegos-Infante, José Alberto; Gonzalez-Laredo, Rubén Francisco; Ramos-Gómez, Minerva; Reynoso-Camacho, Rosalía; Guzmán-Maldonado, Horacio; González-Herrera, Silvia Marina

    2012-02-01

    As part of an ongoing screening on natural products, 4 oak leaves were analyzed as potential nutraceutical beverages. The phenolic composition, antioxidant capacity, and sensory preferences of leaves infusions from Quercus resinosa, Q. sideroxyla, Q. eduadii, and Q. durifolia in comparison with 2 commercial green teas were investigated. Herbal infusions from oak leaves and Green teas (1%, 80 °C, 10 min) were evaluated for total polyphenol content (TPC), total flavonoid content (TFC), HPLC analysis, trolox equivalent antioxidant capacity (TEAC), oxygen radical absorbance capacity (ORAC), soluble solids, pH, color, and consumer preference analysis. Q. resinosa leaves infusions have shown the highest TPC, TEAC, and ORAC values but they have attained the lowest preference score. Quercus leaves infusions with higher content of gallic acid and catechins showed best antioxidant capacity but lower consumer preference. © 2012 Institute of Food Technologists®

  20. Using Paleoecology to Inform Land Management as Climates Change: An Example from an Oak Savanna Ecosystem

    Science.gov (United States)

    Spencer, Jessica D.; Brunelle, Andrea; Hepola, Tim

    2017-12-01

    Oak savanna, a transitional ecosystem between open prairie and dense oak forest, was once widespread in Minnesota. Upon European settlement much of the oak savanna was destroyed. Recently, efforts to restore this ecosystem have increased and often include the reintroduction of fire. Though fire is known to serve an important role within oak savannas, there are currently few studies which address fire regimes on timescales longer than the last century. This research presents a paleoecological history of Sherburne National Wildlife Refuge (SNWR) in MN, USA, spanning the last 8000 years. The objectives of this study were to use charcoal, pollen, and magnetic susceptibility of lake sediments collected from Johnson Slough (JS) within the refuge to evaluate the natural range of variability and disturbance history of the oak savanna within the refuge, assess the success of current restoration strategies, and add to the regional paleoecological history. The mid/late Holocene period of the JS record shows a period of high fire activity from ca. 6500 to 2600 cal year BP, with a shift from prairie to oak savanna occurring over this same period. A (possibly agricultural) disturbance to JS sediments affected the period from ca. 2600 cal year BP to 1963 AD, which includes the time of Euro-American settlement. However, the destruction and subsequent restoration of the oak savanna is evident in a pollen ratio of Quercus:Poaceae, indicating that current restoration efforts have been successful at restoring the oak savanna to within the natural range of variability seen just prior to destruction.

  1. Phytocenological and edaphic characteristics of sessile oak forests on Miroč Mt in northeastern Serbia

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    Cvjetićanin Rade

    2013-01-01

    Full Text Available This research was carried out in natural stands of sessile oak (Quercus petraea agg. Ehrendorfer 1967 on Miroč mountain. Three comunities were investigated: Pure sessile oak forest (Quercetum montanum Čer. et Jov. 1953. s.l., sessile oak-common hornbeam forest (Querco-Carpinetum moesiacum Rud. 1949. s.l. and sessile oak-balkan beech forest (Querco-Fagetum Gliš. 1971. Pure sessile oak forests are found on the following soils: dystric ranker and acid cambic soil on sandstone, dystric ranker and acid cambisols on phyllite, and acid cambic soil on schists. Sessile oak-hornbeam forests grow on sandstone, granite and schists. Sessile oak-beech forests are found on acid cambisol on phyllite and sandstone conglomerate. Various ecological conditions (exposition, slope, altitude, soil types and bedrock on Mt Miroč caused the occurence of diverse sessile oak forest communities, while different states of these forest stands resulted from the implementation of management measures. [Projekat Ministarstva nauke Republike Srbije, br. 37008: Održivo gazdovanje ukupnim potencijalima šuma u Republici Srbiji

  2. Metabarcoding of Bacteria Associated with the Acute Oak Decline Syndrome in England

    Directory of Open Access Journals (Sweden)

    Melanie Sapp

    2016-04-01

    Full Text Available Outbreaks of acute oak decline (AOD have been documented in England from 2006. Both species of native oaks (Quercus robur and Quercus petraea are affected. To complement isolation efforts for identification of putative causative biotic agents and increase our understanding of bacteria associated with oak tissue, five sites in England were chosen for this study. Samples of outer bark, inner bark, sapwood and heartwood were taken from healthy oak and trees with symptoms at varying stages of the syndrome. Furthermore, larval galleries attributed to infestation with Agrilus biguttatus were included. After DNA extraction and amplification of the V3–V5 fragment of the bacterial 16S rRNA genes by pyrosequencing, the dataset was analyzed to identify patterns in bacterial communities in oak tissue samples with and without AOD symptoms at each site. The composition of bacterial communities differed greatly according to the site from which the samples were obtained. Within each site, the composition of the bacteria associated with symptomatic tissue varied between advanced stages of the syndrome and healthy tissue. Key players in healthy and symptomatic tissue were identified and included members of the Gammaproteobacteria related to Pseudomonas sp. or Brenneria goodwinii and members of the Firmicutes.

  3. Revegetation of a uranium mine dump by using fertilizer treated sessile oaks

    OpenAIRE

    Katzur, Joachim; Lange, Christian Albert; Böcker, Lutz

    2011-01-01

    The rehabilitation of contaminated sites and the establishment of suitable trees for revegetation purposes is often problematic due to the mostly suboptimal nutrient supply and the poor humus reservoir. For these reasons hydrogels (Stockosorb®) and novel humus substitutes (NOVIHUM®), serving as long lasting fertilizer (LLF), were recently tested successfully. At the beginning of this multiyear study, those LLFs were administered to the root zone of young sessile oaks (Quercus petraea (Mattusc...

  4. Acorn fall and weeviling in a northern red oak seedling orchard

    Science.gov (United States)

    Daniel R. Miller; Scott E. Schlarbaum

    2005-01-01

    In 2000, we determined levels of damage by acorn weevils (Curculio spp.) and patterns of acorn fall in a northern red oak (Quercus rubra L.) seedling orchard in eastern Tennessee. The mean (±SE) production of acorns among 43 selected trees was 5,930 ± 586 acorns per tree with a maximum production level of 16,969 acorns for one tree...

  5. Performance of northern red oak seedlings across a pH gradient

    Science.gov (United States)

    Anthony S. Davis; Douglass F. Jacobs

    2005-01-01

    Northern red oak (Quercus rubra L.) seedlings were grown from acorns in 4-gallon containers in a greenhouse. Growing medium was amended to a pH of 3.50, 4.25, 5.00, and 5.75 using tri-weekly applications of aluminum sulfate. In addition, seedlings were subjected to either: (1) addition of a 16- to 18-month controlled release fertilizer (CRF), (2)...

  6. Effect of pre-germination treatments on seed physiology and germination of central Himalayan oaks?

    OpenAIRE

    Purohit, Vijay K.; Palni, L. M. S.; Nandi, Shyamal K.

    2009-01-01

    The continuous decline in regeneration of two important species of central Himalayan oak, namely Quercus glauca and Q. leucotrichophora, is of great concern. A study was therefore, carried out to improve germination ability of these species using various presoaking treatments. Seeds of both the species lost viability following storage; tetrazolium staining pattern and germination capacity of seeds following different period of storage at 4 °C and 20 °C indicated retainment of viability for a ...

  7. Tropospheric ozone effects on chemical composition and decomposition rate of Quercus ilex L. leaves.

    Science.gov (United States)

    Baldantoni, Daniela; Fagnano, Massimo; Alfani, Anna

    2011-02-01

    We determined the effects of tropospheric ozone on the chemical composition of Quercus ilex L. leaves and their decomposition, with a view to assessing the influence of ozone on nutrient cycling and the sustainability of Mediterranean holm oak forests. Forming one of the most widespread thermophilous vegetation communities in the area, Q. ilex is a dominant and widespread evergreen oak in the Mediterranean, where concentrations of tropospheric ozone are particularly high. The dynamics of carbon, nitrogen, lignin and cellulose concentrations were monitored for six months during the decomposition of leaves from plants subjected to controlled ozone exposure in open-top chambers. Ozone-exposed leaves, compared to unexposed leaves, showed no significant differences in C, N, lignin and cellulose concentrations prior to the incubation in mesocosms. However, during decomposition, leaves from plants exposed to ozone lost C significantly more slowly and showed a higher C/N ratio than unexposed leaves. Ozone exposure significantly slowed down the decomposition rate, indicating a negative effect of tropospheric ozone on nutrient cycling, which may reduce long-term sustainability of the holm oak forest. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Survey of Navy Dental Clinics: Materiel Complaints Regarding Carbide Burs and Local Anesthetics,

    Science.gov (United States)

    1986-12-01

    Dental Materials and Devices. Revised American Dental Association specification no. 23 for dental excavating burs. JADA 90:459, Feb. 1975. 4. Personal...185. 6. Kaufman, E., Weinstein, P., and Milgrom, P. Difficulties in achieving local anesthesia. JADA 108:205-208, 1984. 7. Personal communication

  9. Microleakage assessment of fissure sealant following fissurotomy bur or pumice prophylaxis use before etching

    Directory of Open Access Journals (Sweden)

    Ali Bagherian

    2013-01-01

    The aim of this investigation was to compare the microleakage level of fissure sealants prepared by a fissurotomy bur or pumice prophylaxis prior to acid etching. Materials and Methods: Ninety freshly extracted healthy maxillary premolar teeth were randomly selected for this investigation. Teeth were then divided into three fissure sealant preparatory groups of A: Fissurotomy bur + acid etch; B: Pumice prophylaxis + acid etch and C: Acid etch alone. Sealant was applied to the occlusal fissures of all specimens using a plastic instrument. This was to avoid any air trap under the sealant. Sample teeth were first thermocycled (1000 cycles, 20 s dwell time and then coated with two layers of nail varnish leaving 2 mm around the sealant. This was then followed by immersion in basic fuchsin 3%. Processed teeth were sectioned longitudinally and examined under a stereomicroscope for microleakage assessment using a score of 0-3. Collected data was then subjected to Kruskall-Wallis Analysis of Variance and Mann-Whitney U-test. P < 0.05 was considered as significant. Results: Teeth in fissurotomy bur and pumice prophylaxis groups had significantly reduced level of microleakage than those in acid etch alone (P = 0.005 and P = 0.003, respectively. Conclusion: Use of fissurotomy bur and pumice prophylaxis accompanied with acid etching appears to have a more successful reduction of microleakage than acid etch alone.

  10. The healing of surgical defects in alveolar bone produced with ultrasonic instrumentation, chisel, and rotary bur.

    Science.gov (United States)

    Horton, J E; Tarpley, T M; Wood, L D

    1975-04-01

    A histologic comparison of the effects of an ultrasonic instrument, a low-speed rotary cutting bur, and a surgical chisel, all used with water coolant, on the rate of healing of dog alveolar bone was made. After reflection of a mucoperiosteal flap, each instrument was used to produce a 3 by 3 by 2 mm. defect in buccal alveolar bone, 3 mm. apical to the alveolar crest and directly overlying the root structure of the right premolar teeth. Dogs were killed immediately following flap replacement with sutures and 3, 7, 14, 28, 56, and 90 days later. Histologic examination of the surgical areas revealed that the bur produced the smoothest surface. At day 3, specimens prepared with the chisel and the ultrasonic instrument exhibited areas of cellular organization along surfaces with the defect and the formation of osteoid in adjacent marrow spaces. At day 7, osteoblastic activity was most pronounced in specimens prepared with the chisel and least in those prepared with the bur. The subsequent rate of healing in later periods appeared histologically to be the best with the use of the chisel, followed closely by the use of the ultrasonic instrument, and the slowest with the bur, the order of which is consistent with the over-all microscopic evaluation of the effect of the three instruments.

  11. Influence of type of bur and acid etching on dentin hydraulic conductance.

    Science.gov (United States)

    Bersezio, Cristian; Martín, Javier; Xaus, Gloria; Vildósola, Patricio; Oliveira, Osmir B; Moncada, Gustavo; Fernández, Eduardo

    2013-01-01

    The aim of this study was to compare ex vivo filtration rate (hydraulic conductance) in human dentin discs mechanically treated with diamond and carbide burs of different grain size with or without acid etching. Method: 60 healthy third molars, recently extracted from patients aged 18-30 years, were cleaned, disinfected (0.1% thymol) and embedded in epoxy resin blocks. Dentin discs were obtained by cutting the occlusal surface with cylindrical rotary instruments, forming nine groups containing 12 specimens each: 1: fine grain (FG); 2: medium grain (MG); 3: coarse grain (CG); 4: carbide (C) burs; 5: FG with acid etching (AE); 6: MG with AE; 7: CG with AE; 8: C with AE; 9: only AE. Hydraulic conductance was determined in the experimental model under constant pressure of 200mm H2O. No difference in hydraulic conductance was observed among dentin discs treated with different types of burs (p = 0.5). Differences were found in the hydraulic conductance of etched and non-etched dentin discs (p type of mechanical bur treatment does not affect dentin hydraulic conductance. Acid etching significantly increases dentin hydraulic conductance.

  12. Effect of the bur grit size on the flexural strength of a glass-ceramic

    Directory of Open Access Journals (Sweden)

    P. P. Kist

    Full Text Available Abstract The purpose of the present study was to determine the biaxial flexural strength (BFS of a CAD/CAM leucite reinforced glass-ceramic ground by diamond burs of different grit sizes and the influence of surface roughness on the BFS. For this, 104 plates were obtained from CAD/CAM ceramic blocks and divided into 4 groups (n = 26, according to bur grit size: extra-fine, fine, medium and coarse. Roughness parameters (Ra, RyMax were measured, and plates were kept dry for 7 days. The flexural test was carried out and BFS was calculated. Ra, RyMax and BFS data were subjected to analysis of variance and post-hoc test. Weibull analysis was used to compare characteristic strength and Weibull modulus. Regression analysis was performed for BFS vs. Ra and RyMax. When burs with coarse grit were used, higher surface roughness values were found, causing a negative effect on the ceramic BFS (117 MPa for extra-fine, and 83 MPa for coarse. Correlation (r between surface roughness and BFS was 0.78 for RyMax and 0.73 for Ra. Increases in diamond grit size have a significant negative effect on the BFS of leucite-reinforced glass-ceramics, suggesting that grinding of sintered glass-ceramic should be performed using burs with the finest grit possible in order to minimize internal surface flaws and maximize flexural strength.

  13. Differences in fine-scale genetic structure and dispersal in Quercus ilex L. and Q. suber L.: consequences for regeneration of mediterranean open woods.

    Science.gov (United States)

    Soto, A; Lorenzo, Z; Gil, L

    2007-12-01

    Cork oak (Quercus suber L.) and holm oak (Q. ilex L.) are among the most important tree species (economically and ecologically) in the Western Mediterranean region, where they define unique open woods (created and maintained by man) known as 'dehesas' in Spain. However, these formations are under increasing threat due to the lack of regeneration. We have analysed spatial genetic structure in a mixed parkland; inferences about gene dispersal have also been performed, according to the isolation by distance model. Noticeable differences have been detected between the species, despite their similar ecological roles. Restricted effective dispersal leads to kin structures in cork oak, up to 70 m, while no genetic structure is observed in holm oak. Our results suggest a very effective dispersal for the latter, with a local historical gene flow estimated between 55 and 95 m. This is the first time regeneration of Mediterranean oak parklands has been assessed from a genetic perspective. Effective gene flow detected for holm oaks allows us to discount the risk of inbreeding over successive generations. Thus, regeneration of Q. ilex dehesas will just require action directed to help the settlement of the saplings (such as limiting grazing). However, in those cases where densities are too low, more intense forestation (such as plantation and/or establishment of appropriate shelter) will be needed. The 'density threshold' for initiating regeneration will probably be higher for cork oak, due to its more limited dispersal and minor full-light tolerance.

  14. Effects of elevated CO2 on foliar quality and herbivore damage in a scrub oak ecosystem.

    Science.gov (United States)

    Hall, Myra C; Stiling, Peter; Moon, Daniel C; Drake, Bert G; Hunter, Mark D

    2005-02-01

    Atmospheric CO2 concentrations have increased exponentially over the last century and continuing increases are expected to have significant effects on ecosystems. We investigated the interactions among atmospheric CO2, foliar quality, and herbivory within a scrub oak community at the Kennedy Space Center, Florida. Sixteen plots of open-top chambers were followed; eight of which were exposed to ambient levels of CO2 (350 ppm), and eight of which were exposed to elevated levels of CO2 (700 ppm). We focused on three oak species, Quercus geminata, Quercus myrtifolia, Quercus chapmanii, and one nitrogen fixing legume, Galactia elliottii. There were declines in overall nitrogen and increases in C:N ratios under elevated CO2. Total carbon, phenolics (condensed tannins, hydrolyzable tannins, total phenolics) and fiber (cellulose, hemicellulose, lignin) did not change under elevated CO2 across plant species. Plant species differed in their relative foliar chemistries over time, however, the only consistent differences were higher nitrogen concentrations and lower C:N ratios in the nitrogen fixer when compared to the oak species. Under elevated CO2, damage by herbivores decreased for four of the six insect groups investigated. The overall declines in both foliar quality and herbivory under elevated CO2 treatments suggest that damage to plants may decline as atmospheric CO2 levels continue to rise.

  15. Antibacterial activity of Quercus ilex bark's extracts.

    Science.gov (United States)

    Berahou, A; Auhmani, A; Fdil, N; Benharref, A; Jana, M; Gadhi, C A

    2007-07-25

    The antibacterial activity of different extracts of Quercus ilex bark (Fagaceae) was studied in vitro against seven reference strains of bacteria by using a disc-diffusion method and agar-dilution method. The ethyl acetate extract (QE), n-butanol extract (QB) and final aqueous layer (QA) were effective against all bacterial strains tested at MICs ranging from 128 to 512 microg/ml. The n-hexane extract (QH) and dichloromethane extract (QD) showed no activity.

  16. Assessment of Tooth Preparation via Er:YAG Laser and Bur on Microleakage of Dentin Adhesives.

    Directory of Open Access Journals (Sweden)

    Zahra Bahrololoomi

    2014-04-01

    Full Text Available Microleakage can be responsible for tooth hypersensitivity, secondary caries, and the possibility of pathological pulp alterations in restored teeth. Recently, alternative methods for tooth preparation such as laser irradiation have been studied; but there are limited studies on primary teeth. The aim of this in vitro study was to compare the degree of microleakage of composite restorations prepared by Er:YAG laser and conventional bur preparation with two adhesive systems in primary teeth.Eighty primary canine teeth were randomly divided into 4 groups. Class V cavities were prepared by Er:YAG laser or diamond bur on buccal surface. The groups were as follows: group1: High speed drill + self-etching adhesive Adper Prompt-L-Pop, group 2: Er:YAG laser + etch & rinse adhesive Adper Single Bond, group 3: High speed drill + Adper Single Bond, group 4: Er:YAG laser + Adper Prompt-L-Pop. Cavities were restored with Filtek Z250 composite resin. Then all of the specimens were polished, thermocycled, immersed in 2% methylene blue solution and sectioned longitudinally. Degree of microleakage was evaluated by two evaluators who assigned the micrleakage score (0 to 3. The original data were analyzed by the Kruskal-Wallis and Dunn's tests.There were significant differences between bur-prepared cavities in the Adper Single Bond and other groups. There were no statistically significant differences between other groups.Laser-prepared cavities showed higher microleakage scores than cavities prepared with diamond bur with etch and rinse adhesive system. No significant difference was revealed between the laser and bur-prepared cavities using self-etch primers.

  17. Germination of hyphal bodies of Pythium spiculum isolated from declining cork oaks at Doñana National Park (Spain

    Directory of Open Access Journals (Sweden)

    PAOLO DE VITA

    2012-01-01

    Full Text Available Pythium spiculum, a recently described new taxon, has been isolated from declining cork oaks (Quercus suber L. at Doñana National Park (south-western Spain. The microorganism can infect and cause root disease in Quercus, but currently it is unknown whether its hyphal bodies can germinate and infect host trees. These hyphal bodies, regardless of shape, have been shown to be able to germinate, producing long germ tubes, sometimes ramified. Zoospore production was not recorded, but hyphal bodies are potential host infective structures in dry soil conditions.

  18. Log-grade volume distribution prediction models for tree species in red oak-sweetgum stands on US mid-south minor stream bottoms

    Science.gov (United States)

    George M. Banzhaf; Thomas G. Matney; Emily B. Schultz; James S. Meadows; J. Paul Jeffreys; William C. Booth; Gan Li; Andrew W. Ezell; Theodor D. Leininger

    2016-01-01

    Red oak (Quercus section Labatae)-sweetgum (Liquidambar styraciflua L.) stands growing on mid-south bottomland sites in the United States are well known for producing high-quality grade hardwood logs, but models for estimating the quantity and quality of standing grade wood in these stands have been unavailable. Prediction...

  19. Stand-level growth and yield component models for red oak-sweetgum forests on Mid-South minor stream bottoms

    Science.gov (United States)

    Emily B. Schultz; J. Clint Iles; Thomas G. Matney; Andrew W. Ezell; James S. Meadows; Theodor D. Leininger; al. et.

    2010-01-01

    Greater emphasis is being placed on Southern bottomland hardwood management, but relatively few growth and yield prediction systems exist that are based on sufficient measurements. We present the aggregate stand-level expected yield and structural component equations for a red oak (Quercus section Lobatae)-sweetgum (Liquidambar styraciflua L.) growth and yield model....

  20. White oak growth after 23 Years in a three-site provenance/progeny trial on a latitudinal gradient in Indiana

    Science.gov (United States)

    Yen-Ning Huang; Hao Zhang; Scott Rogers; Mark Coggeshall; Keith Woeste

    2015-01-01

    To increase the availability of improved, adapted white oak (Quercus alba L.) for midwestern United States landowners, we analyzed data from three 23-year-old provenance/progeny tests of 70 open-pollinated progenies from 17 provenances. Our goal was to estimate the heritability of height growth and range of adaptation and ultimately to determine...

  1. Molecular and morphological characterization of Xiphinema chambersi population from live oak in Jekyll Island, Georgia, with comments on morphometric variations

    Science.gov (United States)

    Zafar A Handoo; Lynn K. Carta; Andrea M. Skantar; Sergei A. Subbotin; Stephen W. Fraedrich

    2016-01-01

    A population of Xiphinema chambersi from the root zone around live oak (Quercus virginiana Mill.) trees on Jekyll Island, GA, is described using both morphological and molecular tools and compared with descriptions of type specimens. Initially, because of a few morphological differences, this nematode was thought to represent...

  2. Assessing anthropogenic and natural disturbances: forest response to similarly aged clearcut and tornado disturbances in an east Tennessee oak-hickory forest

    Science.gov (United States)

    Jonathan C. McGrath; Wayne K. Clatterbuck

    2013-01-01

    In February of 1993, an F3 tornado caused a large-scale disturbance in an east Tennessee oak-hickory (Quercus spp.-Carya spp.) forest. Vegetation response to anthropogenic and natural disturbances was compared by examining two tornado-disturbed areas and five adjacent 1-acre silvicultural clearcut areas unaffected by the tornado...

  3. Evaluation of stem water potential and other tree and stand variables as risk factors for Phytophthora ramorum canker development in coast live oak

    Science.gov (United States)

    Tedmund J. Swiecki; Elizabeth Bernhardt

    2002-01-01

    We conducted a case-control study to examine the role of water stress and various other factors on the development of Phytophthora ramorum cankers in symptomatic (case) and symptomless (control) coast live oak (Quercus agrifolia) and tanoak (Lithocarpus densiflorus). Midday stem water potential (SWP) in ...

  4. An evaluation of seven methods for controlling mountain laurel thickets in the mixed-oak forests of the central Appalachian Mountains, USA

    Science.gov (United States)

    Patrick H. Brose

    2017-01-01

    In the Appalachian Mountains of eastern North America, mountain laurel (Kalmia latifolia) thickets in mixed-oak (Quercus spp.) stands can lead to hazardous fuel situations, forest regeneration problems, and possible forest health concerns. Therefore, land managers need techniques to control mountain laurel thickets and limit...

  5. Use of Nested and Real-Time PCR for the Detection of Ceratocystis fagacearum in the Sapwood of Diseased Oak Species in Minnesota

    Science.gov (United States)

    A. Yang; J. Juzwik

    2017-01-01

    Oak wilt caused by Ceratocystis fagacearum is a significant disease of Quercus spp. in the eastern United States. Early and accurate detection of the pathogen is particularly important when disease control is planned. Nested and real-time polymerase chain reaction (PCR) methods utilizing fungal DNA extracted from sapwood drill...

  6. Discovering the Factors Contributing to the Decline and Mortality of Willow Oaks in the D'Arbonne National Wildlife Refuge, LA.

    Science.gov (United States)

    Theodor D. Leininger

    1998-01-01

    Since the early 1990's, mature willow oaks (Quercus phellos L.) on certain sites in the D'Arbonne National Wildlife Refuge(DNWR), in northeast Louisiana, have shown crown dieback. The die back is progressive with some trees continuing to decline, eventually leading to death, within one to three years. This condition has caused the Refuge forester to...

  7. Estimating Pre-treatment Variation in the Oak Leaf-chewing Insect Fauna of the Missouri Ozark Forest Ecosystem Project (MOFEP)

    Science.gov (United States)

    Robert J. Marquis; Josiane. Le Corff

    1997-01-01

    We describe spatial and temporal variation in the insect herbivore communities associated with the MOFEP, prior to application of contrasting cutting regimes. No pre-treatment differences were found in total insect density on either black (Quercus velutina) or white oak (Q. alba) during 1993-1995. There was great seasonal...

  8. Impacts of deer herbivory and visual grading on the early performance of high-quality oak planting stock in Tennessee, USA

    Science.gov (United States)

    Christopher M. Oswalt; Wayne K. Clatterbuck; Allan E. Houston

    2006-01-01

    The growth of outplanted high-quality 1-0 northern red oak (Quercus rubra L.) seedlings, growth differences between two categories of visually graded seedlings and herbivory by white-tail deer (Odocoileus virginianus (Boddaert)) were examined after two growing seasons. Seedlings were planted in plots receiving three overstory treatments (high grade,...

  9. The effect of acorn insects on the establishment and vigor of northern red oak seedlings in north-central West Virginia

    Science.gov (United States)

    Linda S. Gribko

    1995-01-01

    During a 2-year investigation into the effect of small mammals on northern red oak (Quercus rubra) acorn survival and germination, widespread germination failure and lack of seedling vigor was apparent in control quadrats on one of two watersheds under study. Insects were present in and on the failed acorns but it was unknown whether they were...

  10. Effect of seed position and media on germination of black walnut and northern red oak: implications for nursery production and direct seeding

    Science.gov (United States)

    Anthony S. Davis; Barrett C. Wilson; Douglass F. Jacobs

    2004-01-01

    Germination of black walnut (Juglans nigra L.) and northern red oak (Quercus rubra L.) prior to sowing into containers or bareroot nursery beds can help maintain desired crop density and reduce nursery costs. Recommended techniques for germination of black walnut are labor intensive and require that walnuts be completely covered...

  11. Penicillium cecidicola, a new species on cynipid insect galls on Quercus pacifica in the western United States

    DEFF Research Database (Denmark)

    Seifert, K.A.; Hoekstra, E.H.; Frisvad, Jens Christian

    2004-01-01

    A synnematous species of Penicillium subgenus Biverticillium was found inside emergence tunnels from insect galls (Cynipidae, Hymenoptera, the so-called gall wasps) on scrub oaks (Quercus pacifica Nixon & C.H. Muller) collected in the western United States. The fungus produces synnemata with white...... is a sister species to P. dendriticum, an Australian species with yellow synnemata that also sometimes occurs on insect galls. Notes are included on other Penicillium species we have isolated from insect galls....... isolates exposed to light after 10 days. The fungus produces the extrolite apiculide A and a series of unidentified extrolites also produced by P. panamense. The oak gall species is described here as Penicillium cecidicola and compared with similar species. An ITS phylogeny suggests that P. cecidicola...

  12. Water deficit disrupts male gametophyte development in Quercus ilex.

    Science.gov (United States)

    Bykova, Olga; Limousin, Jean-Marc; Ourcival, Jean-Marc; Chuine, Isabelle

    2018-01-19

    Tree species distribution, and hence forest biodiversity, rely on the reproductive capacity of trees which is currently affected by climate change. Drought-induced pollen sterility could increase as a consequence of more intense and more frequent droughts projected for temperate and Mediterranean regions and threaten the sexual regeneration of trees in these regions. To evaluate this possibility, we examined the effect of long-term partial rainfall exclusion (-27% of precipitation) on male reproductive development in holm oak, Quercus ilex, one of the most important and widespread tree species of the Mediterranean region. We examined anther area, pollen production, pollen abortion as well as viable pollen production in control and dry treatments. Microscopic examinations revealed significant differences in pollen development between trees in the dry and the control treatments, even though anthesis occurred before the annual drought onset. Our results demonstrate that anthers collected from Q. ilex trees in the dry treatment, which experienced long-term increased drought stress especially during the summer time were the same size as anthers in the control treatment, but displayed 25% pollen abortion and almost 20% reduction in pollen production. Subsequently, the number of viable pollen grains in anthers from dry treatment was 35% less than in control. These results suggest a carry-over effect of drought stress on pollen production that could reduce the reproductive success of Q. ilex. The results of this study have broad implications for better understanding of the determinants of tree reproduction by masting and anticipate the outcomes of expected drought increase in the Mediterranean on forest dynamics. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  13. Climate change impact on a mixed lowland oak stand in Serbia

    Directory of Open Access Journals (Sweden)

    Dejan Stojanović

    2015-12-01

    Full Text Available Climatic changes and bad environmental conditions may lead to forests vitality loss and even mortality. This is the reason why increased sanitary felling operations were performed in mixed oak forests in northern Serbia in 2013 in order to solve the severe dieback which affected some Pedunculate oak (Quercus robur L. and Turkey oak (Quercus cerris L. stands, after the very dry years 2011 and 2012.Dendrochronological techniques were applied to both these oak species collected in a stand, to examine the impact of temperature, precipitation and ground water level on forest growth and investigate the potential causes of the dieback.Differences in tree-ring patterns between surviving and dead trees were not significant according to t-value (from 5.68 to 14.20 and Gleichläufigkeit coefficient (from 76% to 82%, this meaning no distinctive responses of the two ecologically different oak species. As for radial increment, pedunculate and Turkey oak trees showed a similar response to environmental variables in this mixed stand. The Simple Pearson’s correlation analysis, which was conducted, showed that among three basic environmental variables (the mean monthly air temperature, the monthly sum of precipitation and the mean monthly water level, proxy of ground water level, the water level of Danube river in May and the temperature in April were statistically related to the growth of the four tree groups: (i pedunculate oak vital, (ii pedunculate oak dead, (iii Turkey oak vital and (iv Turkey oak dead trees, for the period 1961-2010 (p<0.05, n=60. Similar phenomena had already been observed in the Sava River basin for the growth of pure pedunculate oak forests. The long-term decline of the Danube River water level may be related to climate variations and to the changes of water management, river bed, as well as land-use. Together with the increase of temperature, this decline of the water level, and its potential unavailability in the soil, represents a

  14. Characterization of volatile constituents in commercial oak wood chips.

    Science.gov (United States)

    Fernández de Simón, Brígida; Muiño, Iria; Cadahía, Estrella

    2010-09-08

    The volatile composition of the different oak wood pieces (chips of Quercus spp.) that can be found on the market to be used as alternatives to barrels for aging wines, as well as of chips of Quercus pyrenaica which are being introduced, was studied, evaluating the contents of volatile phenols, lactones, furanic compounds, pyranones, phenolic aldehydes, phenolic ketones, and others. In regard to the overall results, the volatile composition of these products varies widely and has not been clearly laid out according to either the oak species or the wood toasting intensity. Taking into account that the different characteristics of alternatives to barrel products are reflected in the wine treated with them and that an oenological profile based on these variables (origin and toasting level) cannot be defined, only an appropriate chemical analysis would reveal the quality of alternative-to-barrel products and allow us to attempt to foresee its effects on the chemical and organoleptic characteristics of the wines treated with them. On the other hand, the Q. pyrenaica alternative products are very similar to those of other species, with some aromatic particularities, such as their high levels of furanic compounds, eugenol, Furaneol, and cis-whiskylactone, and low levels of vanillin.

  15. Experimental minimum threshold for Phytophthora cinnamomi root disease expression on Quercus suber

    Directory of Open Access Journals (Sweden)

    María Socorro SERRANO

    2015-12-01

    Full Text Available Quercus suber seedlings were potted in soils infested with increasing concentrations of Phytophthora cinnamomi chlamydospores and submitted to weekly flooding for 3 months to favour root infections. Increasing quantities of chlamydospores led to an exponential increase in their ability to germinate. Root symptoms (necrosis and/or absence of feeder roots were significantly more severe than those recorded in uninfested soil only for plants potted in soils infested with 61 cfu g-1 or more. Although generated using potting mix, this minimum threshold represents a tool for checking the potential infectivity of infested soils or to assess the effectiveness of some control methods to reduce soil inoculum. However, a low level of root infection was recorded even at 3 cfu g-1. Therefore, long-term disease risk may be present whenever the pathogen is detectable in oak forest soils.

  16. Assessment of physicochemical and antioxidant characteristics of Quercus pyrenaica honeydew honeys.

    Science.gov (United States)

    Shantal Rodríguez Flores, M; Escuredo, Olga; Carmen Seijo, M

    2015-01-01

    Consumers are exhibiting increasing interest in honeydew honey, principally due to its functional properties. Some plants can be sources of honeydew honey, but in north-western Spain, this honey type only comes from Quercus pyrenaica. In the present study, the melissopalynological and physicochemical characteristics and the antioxidant properties of 32 honeydew honey samples are described. Q. pyrenaica honeydew honey was defined by its colour, high pH, phenols and flavonoids. Multivariate statistical techniques were used to analyse the influence of the production year on the honey's physicochemical parameters and polyphenol content. Differences among the honey samples were found, showing that weather affected the physicochemical composition of the honey samples. Optimal conditions for oak growth favoured the production of honeydew honey. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. The negative impact of intentionally introduced Quercus rubra L. on a forest community

    Directory of Open Access Journals (Sweden)

    Beata Woziwoda

    2014-03-01

    Full Text Available Some alien woody species used in commercial forestry become invasive and, as invaders, cause major problems in natural and semi-natural ecosystems. However, the deliberate introduction of aliens can bring unintended negative changes also within areas of their cultivation. This paper presents the effects of the intentional introduction of the North-American Quercus rubra in European mixed Scots pine-Pedunculate oak forests (POFs: Querco roboris-Pinetum (W. Mat. 1981 J. Mat. 1988. Phytosociological data from field research combined with GIS data analysis of the current distribution of Northern Red oak in the studied habitat were used to determine the composition and structure of forest communities in plots with and without Q. rubra participation.  The results show that Q. rubra significantly reduces native species richness and abundance, both in old-growth and in secondary (post-agricultural forests. Not one resident vascular plant benefits from the introduction of Northern Red oak and only a few are able to tolerate its co-occurrence. The natural restocking of all native woody species is also strongly limited by this alien tree.  The introduction of Northern Red oak significantly limits the environmental functions of the POF ecosystem and weakens its economic and social aspects. However, its further cultivation is justified from an economic point of view, as the essential function of the studied forests is commercial timber production, and the introduction of this fast growing alien tree supports the provisioning ecosystem services. A clear description of the level of trade-off between the accepted negative and positive effects of the introduction of Q. rubra on forest ecosystem services requires further interdisciplinary studies.

  18. A discriminant analysis of introgression between Quercus prinus L. and Quercus alba L.

    Science.gov (United States)

    F. Thomas Ledig; Robert W. Wilson; John W. Duffield; Gerald Maxwell

    1969-01-01

    The natural hybrid between rock chestnut oak, Q. prinus, and white oak, Q. alba, was named Q. x saulii by Schneider (1904). The nomenclature used herein follows that of Little (1953). Q. x saulii is frequently identified throughout the area of sympatry of...

  19. Een vergelijkend ecologisch onderzoek in opstanden van Quercus borealis Michx F. en Quercus robur L.

    NARCIS (Netherlands)

    Smeets, J.G.P.M.

    1957-01-01

    Extensive investigations into the biotic, edaphic and climatic factors of the growth site and timber production figures showed that Quercus borealis Michx.f. was a very useful hardwood species for the Netherlands, especially on well drained but moist sites. The great-adaptability of this

  20. Aroma potential of oak battens prepared from decommissioned oak barrels.

    Science.gov (United States)

    Li, Sijing; Crump, Anna M; Grbin, Paul R; Cozzolino, Daniel; Warren, Peter; Hayasaka, Yoji; Wilkinson, Kerry L

    2015-04-08

    During barrel maturation, volatile compounds are extracted from oak wood and impart aroma and flavor to wine, enhancing its character and complexity. However, barrels contain a finite pool of extractable material, which diminishes with time. As a consequence, most barrels are decommissioned after 5 or 6 years. This study investigated whether or not decommissioned barrels can be "reclaimed" and utilized as a previously untapped source of quality oak for wine maturation. Oak battens were prepared from staves of decommissioned French and American oak barrels, and their composition analyzed before and after toasting. The oak lactone glycoconjugate content of untoasted reclaimed oak was determined by liquid chromatography-tandem mass spectrometry, while the concentrations of cis- and trans-oak lactone, guaiacol, 4-methlyguaiacol, vanillin, eugenol, furfural, and 5-methylfurfural present in toasted reclaimed oak were determined by gas chromatography-mass spectrometry. Aroma potential was then evaluated by comparing the composition of reclaimed oak with that of new oak. Comparable levels of oak lactone glycoconjugates and oak volatiles were observed, demonstrating the aroma potential of reclaimed oak and therefore its suitability as a raw material for alternative oak products, i.e., chips or battens, for the maturation of wine. The temperature profiles achieved during toasting were also measured to evaluate the viability of any yeast or bacteria present in reclaimed oak.

  1. Sweets for the foe - effects of nonstructural carbohydrates on the susceptibility of Quercus robur against Phytophthora quercina.

    Science.gov (United States)

    Angay, Oguzhan; Fleischmann, Frank; Recht, Sabine; Herrmann, Sylvie; Matyssek, Rainer; Oßwald, Wolfgang; Buscot, François; Grams, Thorsten E E

    2014-09-01

    The root-rot pathogen Phytophthora quercina is a key determinant of oak decline in Europe. The susceptibility of pedunculate oak (Quercus robur) to this pathogen has been hypothesized to depend on the carbon availability in roots as an essential resource for defense. Microcuttings of Q. robur undergo an alternating rhythm of root and shoot growth. Inoculation of mycorrhizal (Piloderma croceum) and nonmycorrhizal oak roots with P. quercina was performed during both growth phases, that is, root flush (RF) and shoot flush (SF). Photosynthetic and morphological responses as well as concentrations of nonstructural carbohydrates (NSC) were analyzed. Infection success was quantified by the presence of pathogen DNA in roots. Concentrations of NSC in roots depended on the alternating root/shoot growth rhythm, being high and low during RF and SF, respectively. Infection success was high during RF and low during SF, resulting in a significantly positive correlation between pathogen DNA and NSC concentration in roots, contrary to the hypothesis. The alternating growth of roots and shoots plays a crucial role for the susceptibility of lateral roots to the pathogen. NSC availability in oak roots has to be considered as a benchmark for susceptibility rather than resistance against P. quercina. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  2. Diversity and specificity of ectomycorrhizal fungi retrieved from an old-growth Mediterranean forest dominated by Quercus ilex.

    Science.gov (United States)

    Richard, F; Millot, S; Gardes, M; Selosse, M-A

    2005-06-01

    We analysed the ectomycorrhizal (ECM) fungal diversity in a Mediterranean old-growth Quercus ilex forest stand from Corsica (France), where Arbutus unedo was the only other ECM host. On a 6400 m2 stand, we investigated whether oak age and host species shaped below-ground ECM diversity. Ectomycorrhizas were collected under Q. ilex individuals of various ages (1 yr seedlings; 3-10 yr saplings; old trees) and A. unedo. They were typed by ITS-RFLP analysis and identified by match to RFLP patterns of fruitbodies, or by sequencing. A diversity of 140 taxa was found among 558 ectomycorrhizas, with many rare taxa. Cenococcum geophilum dominated (35% of ECMs), as well as Russulaceae, Cortinariaceae and Thelephoraceae. Fungal species richness was comparable above and below ground, but the two levels exhibited Quercus ilex age did not strongly shape ECM diversity. The two ECM hosts, A. unedo and Q. ilex, tended to share few ECM species (< 15% of the ECM diversity). Implications for oak forest dynamics are discussed.

  3. Impact of stereoide fungi on decomposition of oak wood and possibility of its protection

    Directory of Open Access Journals (Sweden)

    Mirić Milenko

    2005-01-01

    Full Text Available Four stereoide fungi, causers of decay of oak wood, have been investigated as follows: Stereum hirsutum, Chondrostereum purpureum, Stereum rugosum and Xylobolus frustulatus. The field tests have been undertaken in order to determine the influence of the stereoide fungi on the wood of Sessile oak (Quercus petraea and Austrian oak (Quercus robur. Artificial inoculations with mycelia have been provoked in vital standing trees, as well as in laying trunks. The appearance of dying back symptoms, the rate of mycelia spread through the stem, speed of wound callusing and appearance of fruit bodies or decay symptoms, have been observed. The protection possibility of trunks has been tested as well by using preservatives based on chromo-cupric boron salts, dichlorfluanide and chlorinepyriphos, cupric naphtenates, as well as with antiseptic paste. Microscopically analysis of attacked oak wood has been performed by utilizing of scanning electron (SEM and standard optical microscope providing normal, fluorescence, polarized and UV light, so that anatomical changes of the wood structure elements influenced by fungal activity have been noted.

  4. De la industrialització de les comarques de Girona al vapor Burés

    OpenAIRE

    Tarrés Turon, Josep

    2005-01-01

    Aquest article vol mostrar que la industrialització de Catalunya també va ser important a les comarques properes a la ciutat de Girona, especialment a la vall d’Anglès, ja que en aquesta població es conserva el vapor Burés, una màquina de vapor del principi del segle XX en molt bon estat. L'article es presenta en un to divulgador amb ànim de provocar anàlisis mes rigoroses dels temes tractats. En aquest sentit, l'apartat de la descripció tècnica del vapor Burés pretén estimular el seu estudi ...

  5. Magnetic resonance imaging induced acute midfacial pain - incidental finding of a dislocated dental bur.

    Science.gov (United States)

    Voss, Jan Oliver; Raguse, Jan-Dirk; Hoffmeister, Bodo; Adolphs, Nicolai

    2015-01-01

    To describe the management of a patient with an initially unnoticed dislocated dental bur in the maxillary sinus that became symptomatic during a magnetic resonance imaging (MRI) scan. A MRI scan provoked strong midfacial pain in a 31-year-old male patient, who exhibited ambiguous neurologic impairment consistent with multiple sclerosis. Conventional radiography revealed an opaque foreign body in close proximity to the orbital floor that most likely caused the painful symptoms during the MRI. After additional X-ray computed tomography (X-ray CT) scans were performed, a metal dental bur was removed by a combined transconjunctival and transnasal approach under perioperative antibiotic treatment. The disappearance of instruments during surgical procedures requires diligent investigation and immediate retrieval.

  6. Phylogenetic relationships of the genus Quercus L. (Fageceae) from ...

    African Journals Online (AJOL)

    ProBook

    2016-10-05

    Oct 5, 2016 ... The classification of the species of Quercus by. Hedge and Yaltırık (1982), two Turkish authors, has been of great contribution to the research in this field. Before the classification of Hedge and Yaltırık, many intraspecific taxa were classified as species and species concept for Quercus taxa was quite narrow ...

  7. Characterization of Quercus species distributed in Jordan using ...

    African Journals Online (AJOL)

    User

    2013-03-20

    Mar 20, 2013 ... Genetic diversity among 25 natural populations of three different species of Quercus in Jordan at morphological and molecular levels using random amplified polymorphic DNA (RAPD) primers was assessed. Significant morphological and molecular variations among and within 25 Quercus populations ...

  8. Studies on Wound Healing Properties of Quercus infectoria ...

    African Journals Online (AJOL)

    Purpose: The aim of the present study was to investigate the wound healing activity of the selected Indian medicinal plant Quercus infectoria. Method: Ethanol extract of the shade-dried leaves of Quercus infectoria was studied for its effect on wound healing in rats, using incision, excision and dead-space wound models, ...

  9. Comparison of Dentin Permeability After Tooth Cavity Preparation with Diamond Bur and Er:YAG Laser

    Directory of Open Access Journals (Sweden)

    Masoumeh Hasani Tabatabaei

    2016-05-01

    Full Text Available Objectives: The aim of this study was to compare the permeability of dentin after using diamond bur and Er:YAG laser.Materials and Methods: Seventy-two recently extracted, intact, and restoration-free human permanent molars were used in this study. The samples were randomly divided into three groups of 24 each and class I cavities were prepared as follows. Group 1: High speed diamond bur with air and water spray. Group 2: Er:YAG laser. Group 3: Er:YAG laser followed by additional sub-ablative laser treatment. Each group consisted of two subgroups with different cavity depths of 2mm and 4mm.  The entire cavity floor was in dentin. Two samples from each subgroup were observed under scanning electron microscope (SEM. The external surfaces of other samples were covered with nail varnish (except the prepared cavity and immersed in 0.5% methylene blue solution for 48 hours.  After irrigation of samples with water, they were sectioned in bucco-lingual direction. Then, the samples were evaluated under a stereomicroscope at ×160 magnification. The data were analyzed using two-way ANOVA and Tukey’s HSD test.Results: Two-way ANOVA showed significant difference in permeability between groups 2 and 3 (laser groups with and without further treatment and group 1 (bur group. The highest permeability was seen in the group 1. There was no significant difference in dentin permeability between groups 2 and 3 and no significant difference was observed between different depths (2mm and 4mm.Conclusion: Cavities prepared by laser have less dentin permeability than cavities prepared by diamond bur.

  10. Chromatin (dis)organization and cancer: BUR-binding proteins as biomarkers for cancer.

    Science.gov (United States)

    Galande, Sanjeev

    2002-06-01

    Malignant transformation of cells is associated with changes in gene expression. Gross alterations in chromatin organization may be involved in such gene dysregulation, as well as the involvement of specific transcription factors. Specialized genomic DNA segments that exhibit high affinity to the nuclear matrix in vitro have been designated as matrix/scaffold attachment regions (MARs/SARs). MARs are postulated to anchor chromatin onto the nuclear matrix, thereby organizing genomic DNA into topologically distinct loop domains that are important in replication and transcription. In support of this notion, MARs often colocalize or exist in close proximity to regulatory sequences including enhancers. Base unpairing regions (BURs) are typically 100-150 bp regions within MARs, possess an intrinsic propensity to unwind under negative superhelical strain, and are considered to be hallmark of MARs. To investigate a potential mechanism that could lead to significant alterations in gene expression in cancer cells, this review focuses on a group of chromatin-associated proteins that specifically recognize double stranded BURs. Several important proteins have been identified from cancer cells as BUR-binding proteins, including poly (ADP-ribose) polymerase (PARP-1), Ku autoantigen, SAF-A, HMG-I(Y), nucleolin and p53. Many of these proteins are dramatically upregulated in malignancy of the breast. Increase in the amount of these BUR-binding proteins, some of which are known to interact with each other, may not only provide an architectural core but also recruit functional multi-molecular complexes at the base of chromatin loops to affect multiple distant genes. Experimental strategies by which these proteins can be exploited as carcinoma-specific diagnostic markers and as targets for antineoplastic therapy are discussed.

  11. Microtensile bond strength of indirect resin composite to resin-coated dentin: interaction between diamond bur roughness and coating material.

    Science.gov (United States)

    Kameyama, Atsushi; Oishi, Takumi; Sugawara, Toyotarou; Hirai, Yoshito

    2009-02-01

    This aim of this study was to determine the effect of type of bur and resin-coating material on microtensile bond strength (microTBS) of indirect composite to dentin. Dentin surfaces were first ground with two types of diamond bur and resin-coated using UniFil Bond (UB) or Adper Single Bond (SB), and then bonded to a resin composite disc for indirect restoration with adhesive resin cement. After storage for 24 hr in distilled water at 37 degrees C, microTBS was measured (crosshead speed 1 mm/min). When UB was applied to dentin prepared using the regular-grit diamond bur, microTBS was significantly lower than that in dentin prepared using the superfine-grit bur. In contrast, no significant difference was found between regular-grit and superfine-grit bur with SB. However, more than half of the superfine-grit specimens failed before microTBS testing. These results indicate that selection of bur type is important in improving the bond strength of adhesive resin cement between indirect resin composite and resin-coated dentin.

  12. Cutting efficiency of diamond burs operated with electric high-speed dental handpiece on zirconia.

    Science.gov (United States)

    Nakamura, Keisuke; Katsuda, Yusuke; Ankyu, Shuhei; Harada, Akio; Tenkumo, Taichi; Kanno, Taro; Niwano, Yoshimi; Egusa, Hiroshi; Milleding, Percy; Örtengren, Ulf

    2015-08-28

    Zirconia-based dental restorations are becoming used more commonly. However, limited attention has been given to the difficulties experienced, concerning cutting, in removing the restorations when needed. The aim of the present study was to compare the cutting efficiency of diamond burs, operated using an electric high-speed dental handpiece, on zirconia (Zir) with those on lithium disilicate glass-ceramic (LD) and leucite glass-ceramic (L). In addition, evaluation of the cutting efficiency of diamond burs on Zir of different thicknesses was performed. Specimens of Zir were prepared with thicknesses of 0.5, 1.0, 2.0, and 4.0 mm, and specimens of LD and L were prepared with a thickness of 1.0 mm. Cutting tests were performed using diamond burs with super coarse (SC) and coarse (C) grains. The handpiece was operated at 150,000 rpm with a cutting force of 0.9 N. The results demonstrated that cutting of Zir took about 1.5- and 7-fold longer than cutting of LD and L, respectively. The SC grains showed significantly higher cutting efficiency on Zir than the C grains. However, when the thickness of Zir increased, the cutting depth was significantly decreased. As it is suggested that cutting of zirconia is time consuming, this should be taken into consideration in advance when working with zirconia restorations. © 2015 Eur J Oral Sci.

  13. Brazed Diamond Micropowder Bur Fabricated by Supersonic Frequency Induction Heating for Precision Machining

    Science.gov (United States)

    Ma, Bojiang; Lou, Jianpeng; Pang, Qian

    2014-04-01

    The common brazed diamond micropowder bur fabricated in a vacuum furnace produces an even brazing alloy surface. The small brazed diamond grits show low outcropping from the brazing alloy surface, and the chip space between them is small. The bur shows a low grinding efficiency and poor heat dissipation. In this study, a brazed diamond micropowder bur was fabricated by supersonic frequency induction heating. The method afforded a fluctuant surface on the brazing alloy. The brazed diamond grits with an outcropping height distributed uniformly on the fluctuant surface. The fluctuant surface showed a certain chip space. These characteristics of the tool increased the grinding efficiency and decreased the temperature of the grinding arc area. The roughness R a of the ceramic tile surface trimmed by the tool cylinder was between 0.09 and 0.12 μm. In the first 90 min, the decrease in the weight of the ceramic tile ground by the tool cylinder was higher than that ground by the tool fabricated in a vacuum furnace. When the ceramic tile was cylindrically ground, the temperature of the grinding arc area measured using a thermocouple remained below 70 °C.

  14. Is curettage and high-speed burring sufficient treatment for aneurysmal bone cysts?

    Science.gov (United States)

    Wang, Edward H M; Marfori, Michael L; Serrano, Ma Victoria T; Rubio, Donnel Alexis

    2014-11-01

    To decrease the recurrence rate after intralesional curettage for aneurysmal bone cysts, different adjuvant treatments have been recommended. Liquid nitrogen spray and argon beam coagulation have provided the lowest recurrence rates, but unlike the high-speed burr, these adjuvants are not always available in operating rooms. We asked: (1) Is high-speed burring alone sufficient as an adjuvant to curettage with respect to recurrence rates? (2) What is the complication rate from this technique? (3) What are the risk factors for local recurrence? A retrospective review of the database of the University Musculoskeletal Tumor Unit and the private files of the senior author (EHW) for a period of 19 years (1993-2011) was performed to identify all patients histologically diagnosed with primary aneurysmal bone cyst. During that period, patients with aneurysmal bone cysts were treated with intralesional curettage, burring, and bone grafting if the lesions showed an adequate cortical wall or a wall with thinned out portions which could be reconstructed with bone grafting. Based on those indications, we treated 54 patients for this condition. Of those, 18 were treated using approaches other than burring because they did not meet the defined indications, and an additional five patients were lost to followup before 2 years, leaving 31 patients for analysis, all of whom were followed up for at least 2 years (mean, 7 years; range, 2-18 years). Of these 31 patients, one had a recurrence (3.2%). Complications using this approach occurred in three patients (9.7%), and included growth plate deformity (1) and genu varus (2) secondary to collapse of the reconstructed condyle. With only one recurrence, we cannot answer what the risk factors might be for recurrence; however, the one patient with recurrence presented with a large lesion and a pathologic fracture. Curettage, burring, and bone grafting compare favorably in the literature with other approaches for aneurysmal bone cysts

  15. Changes in Ectomycorrhizal Diversity in a Declining Quercus ilex Coastal Forest

    Directory of Open Access Journals (Sweden)

    L. Montecchio

    2004-04-01

    Full Text Available Oak decline is generally accepted to be the result of a dynamic interaction between oaks and a mix of abiotic and biotic causes, within which environmental stresses (drought, salinity, frost, low fertility may be important as predisposing factors. As a result of these interactions, trees gradually begin to show symptoms of general suffering, which below ground consist of functional and anatomical modifications to the rootlets and changes in the ectomycorrhizal status. The present study was performed in a coastal Quercus ilex forest, where decline symptoms appeared after heavy land reclamation in the adjoining areas, which caused a rapid lowering of the ground water level and the underground intrusion of seawater from the neighbouring Adriatic Sea into the forest itself. A forest survey including examination of rootlet features from asymptomatic and declining trees suggested that drought and salinity were involved in this decline. The relative frequency of the most recurrent ectomycorrhizal morphotypes distinguished clearly between asymptomatic, weakly declining and strongly declining trees, suggesting that the occurrence and distribution of only a limited number of morphotypes can give an indication of the severity of the decline. Moreover, of all the morphotypes observed only one third were found in all three decline classes, while the remaining two thirds were gradually replaced by others as the proportion of declining trees increased, where the number of morphotypes was greater. The hypothesis of an adaptive response of the ectomycorrhizal community to decline or to the predisposing factors of decline is discussed.

  16. PRODUCTOS FORESTALES NO MADERABLES ASOCIADOS A BOSQUES DE ROBLE Quercus humboldtii Bonpl EN LA VEGA, CAUCA

    Directory of Open Access Journals (Sweden)

    ALEJANDRA POTOSÍ GUTIÉRREZ

    2017-12-01

    Full Text Available The Oak Forest (Quercus humboldtii Bonpl are affected by inappropriate uses, despite the many natural resources they have and have been feedstock of local communities to develop their daily activities. Therefore, Non-Timber Forest Products (NTFPs from the Oak Forest were identified in the municipality of La Vega, Cauca Department, to classify them according to the use given by the communities. The information was obtained through field observation techniques, interviews and oral communication. 74 NTFPs were identified belonging to 10 categories of generic use of which stressed "Medicinal" and "Food and beverages" represented by 54,1% and 21,6%, respectively, of total products found. The most consumed foods correspond to the honey, infusion from the seeds of Q. humboldtii and callampas (Pleurotus ostreatus, about which, the physical-chemical composition has already been reported. It was recorded that the fruits of Panopsis rubra, are secondary foods consumed by people, whose proximate analysis revealed the contents of appreciable amounts of carbohydrate (85,43%, indicating that they can be very helpful as a supply of energy for the human being.

  17. A comparative analysis of stomata and leaf trichome characteristics in Quercus robur L. genotypes

    Directory of Open Access Journals (Sweden)

    Nikolić Nataša P.

    2003-01-01

    Full Text Available The objective of this study was to determine genotype variability of leaf trichome and stoma characteristics. Leaves were sampled from seventeen pedunculate oak (Quercus robur L genotypes originating from clonal seed orchard Banov Brod (Srem, the Vojvodina Province. The pedunculate oak has hypostomatal leaves. Statistically significant differences were found for the dimensions and density of stomata. Genotype variability of stomatal dimensions was less pronounced in comparison with their density (CV = 8.88%. Stomata number ranged from 530 to 791 per mm2 of leaf area; genotypes 18 and 25 could be distinguished from the others for the highest stomata number per leaf unit area, genotype 35 for the lowest number. In all genotypes, only solitary eglandular trichomes were observed on the adaxial leaf surface while both solitary eglandular and uniseriate glandular hairs were present on the abaxial surface. Single glandular trichomes were observed in all genotypes, while some of them were characterized by the presence of two (genotypes 4, 5, 6, 16, 22, 25, 28, 29, 30, 35, 38, 40, and 85 or three (genotypes 16, 25, 35 hairs joined by their basal cells.

  18. Comparative anatomical analysis of the cotyledonary region in three Mediterranean Basin Quercus (Fagaceae).

    Science.gov (United States)

    Pascual, Gemma; Molinas, Marisa; Verdaguer, Dolors

    2002-03-01

    Anatomical changes at the cotyledonary node from the embryo to the seedling stage in Quercus coccifera, Q. ilex, and Q. humilis were investigated by light and scanning electron microscopy techniques. Mature embryos of Q. humilis possess 2-3 pairs of leaf primordia and a pair of cotyledonary buds, whereas in Q. coccifera and Q. ilex there are two incipient primordia, and cotyledonary buds are not observed until 1 wk after germination. In all three species the cotyledonary buds multiply, forming bud clusters, and a vascular connection is well established within 5-6 wk after germination. As development proceeds, the cotyledonary region becomes woody, but buds, which are exogenous in origin, never become embedded in the periderm. In comparison with Q. suber, another native Mediterranean Basin oak, the cotyledonary node is short and axillary buds are not present below the insertion of cotyledons. In addition, starch accumulation in the cotyledonary region is not observed from histological analysis in the three oaks. Therefore, in Q. coccifera, Q. ilex, and Q. humilis seedlings the cotyledonary node can be considered to be an important regenerative structure enabling them to resprout after the elimination of the shoot above the cotyledons, despite the absence of a lignotuberous structure.

  19. Pre-dispersal strategies by Quercus schottkyana to mitigate the effects of weevil infestation of acorns.

    Science.gov (United States)

    Xia, Ke; Harrower, William L; Turkington, Roy; Tan, Hong-Yu; Zhou, Zhe-Kun

    2016-11-22

    We investigated how pre-dispersal strategies may mitigate the effects of weevil infestation of acorns in a population of Quercus schottkyana, a dominant oak in Asian evergreen broad-leaved forests, and assess if weevil infestation contributes to low seedling recruitment. We counted the number of acorns produced, daily from the end of August to mid-late November for 9 years from 2006-2014. We also recorded the rate of acorn infestation by weevils and acorn germination rates of weekly collections. Annual acorn production was variable, but particularly low in 2011 and 2013. There was no trade-off between acorn production and acorn dry mass. However, acorns produced later in the season were significantly heavier. For most years: (i) the rate of weevil infestation was negatively density dependent (a greater proportion of acorns died with increased acorn density), (ii) the percentage germination of acorns was positively density dependent (proportionately more acorns germinated with increased density), and (iii) as the season progressed, the percentage of infested acorns declined while germination rates increased. Finally, (iv) maximum acorn production, percentage infestation and percentage germination were asynchronous. Although pre-dispersal mortality is important it is unlikely to be the primary factor leading to low recruitment of oak seedlings.

  20. Genetic diversity increases insect herbivory on oak saplings.

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    Bastien Castagneyrol

    Full Text Available A growing body of evidence from community genetics studies suggests that ecosystem functions supported by plant species richness can also be provided by genetic diversity within plant species. This is not yet true for the diversity-resistance relationship as it is still unclear whether damage by insect herbivores responds to genetic diversity in host plant populations. We developed a manipulative field experiment based on a synthetic community approach, with 15 mixtures of one to four oak (Quercus robur half-sib families. We quantified genetic diversity at the plot level by genotyping all oak saplings and assessed overall damage caused by ectophagous and endophagous herbivores along a gradient of increasing genetic diversity. Damage due to ectophagous herbivores increased with the genetic diversity in oak sapling populations as a result of higher levels of damage in mixtures than in monocultures for all families (complementarity effect rather than because of the presence of more susceptible oak genotypes in mixtures (selection effect. Assemblages of different oak genotypes would benefit polyphagous herbivores via improved host patch location, spill over among neighbouring saplings and diet mixing. By contrast, genetic diversity was a poor predictor of the abundance of endophagous herbivores, which increased with individual sapling apparency. Plant genetic diversity may not provide sufficient functional contrast to prevent tree sapling colonization by specialist herbivores while enhancing the foraging of generalist herbivores. Long term studies are nevertheless required to test whether the effect of genetic diversity on herbivory change with the ontogeny of trees and local adaptation of specialist herbivores.