47,835 research outputs found

    Supernumerary (B) chromosomes in populations of Picea abies (L.) H. Karst. from Western Rhodopes (Bulgaria)

    No full text
    Investigations on B chromosomes found for the first time for Picea abies (L.) H. Karst. have been conducted. Seeds of Picea abies from two populations of Western Rhodopes (Bulgaria) located at the southern border of species range, and protected according to Bern Convention and EC Habitat Directive were collected for this study. Mixoploidy was detected in some germinating seeds of Picea abies. It was found that metaphase cells of germinating seeds contain 0–4 B chromosomes of both metacentric and submetacentric types. The variability of B chromosomes number and their occurrence was observed. Along with B chromosomes, some chromosome aberrations such as fragments and ring chromosomes were revealed in metaphase cells of Picea abies from studied populations. The possible adaptive role of B chromosomes presence for Picea spp. is discussed.Проведено исследование В-хромосом, обнаруженных впервые у вида Picea abies (L.) H. Karst. Для настоящего исследования семена собраны из двух популяций Picea abies в Западных Родопах (Болгария), расположенных на южной границе видового ареала и охраняемых в соответствии с Бернской конвенцией и Директивой ЕС о местообитаниях. В отдельных проростках семян Picea abies найдена миксоплоидия. Обнаружено, что метафазные клетки проростков семян из изученных популяций Picea abies содержат 0–4 В-хромосомы как метацентрического, так и субметацентрического типов. Наблюдается изменчивость числа В-хромосом и их появления. Наряду с В-хромосомами в метафазных клетках Picea abies выявлены хромосомные мутации – фрагменты и кольцевые хромосомы. Обсуждается возможная адаптивная роль присутствия В-хромосом у видов Picea.Проведено дослідження В-хромосом, виявлених вперше у виду Picea abies (L.) H. Karst. Для даного дослідження насіння зібране з двох популяцій Picea abies в Західних Родопах (Болгария), що розташовані на південному кордоні видового ареалу та охороняються відповідно до Бернської конвенції та Директивою ЄС про місце розповсюдження. В окремих проростках насіння Picea abies знайдено міксоплоїдію. Виявлено, що метафазні клітини проростків насіння з вивчених популяцій Picea abies містять 0–4 В-хромосоми як метацентричного, так і субметацентричного типів. Спостерігається мінливість числа В-хромосом. Поряд з В-хромосомами у метафазних клітинах Picea abies виявлено хромосомні мутації – фрагменти та кільцеві хромосоми. Обговорюється можлива адаптивна роль присутності В-хромосом у видів Picea

    Vegetationshistoria och etablering av Picea abies (L.) Karst. i Härjedalen, mellersta Sverige

    Get PDF
    The traditional theory about Picea abies (L.) Karst. arrival and establishment in Sweden is being revised. Until Picea abies megafossils were radiocarbon dated between the late-Glacial and the mid-Holocene (Kullman, 2000), it was widely accepted that Picea abies established at the Swedish East coast approximately 3500 B.P., then spreading to the South and West. Early- to mid-Holocene occurrence of Picea abies in previous pollen diagrams, such as Lundqvist (1969), that were considered as long distance pollen transport, could now be interpreted as early outposts of Picea abies. The overall aim of this project is to reconstruct the past vegetation in central Sweden. The specific question is whether pollen records can verify the early-Holocene Picea abies establishment in Sweden as is suggested by Lundqvist (1969). A pollen analysis study was performed in Stenhammaren, in the Härjedalen province (central Sweden), a few kilometres from the site with high early pollen proportion of Picea abies. The results permit the reconstruction of the past vegetation in the site, however no early Picea abies pollen has been found. Nevertheless, the presence of Picea abies trees near the study site in the early-Holocene should not be discarded, and further research is needed. RESUMEN La teoría tradicional acerca de la llegada y establecimiento de Picea abies (L.) Karst. en Suecia está siendo revisada. Hasta que megafósiles de Picea abies fueron datados por radiocarbono entre el fin de la glaciación y el Holoceno Medio (Kullman, 2000), era ampliamente aceptado que Picea abies se estableció en la costa este de Suecia aproximadamente 3500 A.P., propagándose más tarde hacia el sur y oeste. La aparición en el temprano y medio Holoceno de Picea abies en diagramas de polen previos, tales como Lundqvist (1969), eran considerados polen transportado desde larga distancia, ahora podrían ser interpretados como posiciones tempranas de Picea abies. El objetivo general de este proyecto es reconstruir el pasado de la vegetación en el centro de Suecia. La cuestión específica es si registros de polen pueden verificar el establecimiento de Picea abies en Suecia al comienzo del Holoceno, como sugiere Lundqvist (1969). Se ha llevado a cabo un estudio de análisis de polen en Stenhammaren, en la provincia de Härjedalen (centro de Suecia), a pocos kilómetros del lugar con alta proporción de polen de Picea abies temprano. Los resultados permiten la reconstrucción del pasado de la vegetación en el lugar, sin embargo no se ha encontrado polen temprano de Picea abies. A pesar de todo, la presencia de árboles de Picea abies cerca del lugar de estudio al comienzo del Holoceno no debe ser descartada, y más investigaciones son necesarias

    Comparative in silico analysis of SSRs in coding regions of high confidence predicted genes in Norway spruce (Picea abies) and Loblolly pine (Pinus taeda)

    Get PDF
    Background: Microsatellites or simple sequence repeats (SSRs) are DNA sequences consisting of 1-6 bp tandem repeat motifs present in the genome. SSRs are considered to be one of the most powerful tools in genetic studies. We carried out a comparative study of perfect SSR loci belonging to class I (>= 20) and class II (>= 12 and < 20 bp) types located in coding regions of high confidence genes in Picea abies and Pinus taeda. SSRLocator was used to retrieve SSRs from the full length CDS of predicted genes in both species. Results: Trimers were the most abundant motifs in class I followed by hexamers in Picea abies, while trimers and hexamers were equally abundant in Pinus taeda class I SSRs. Hexamers were most frequent within class II SSRs followed by trimers, in both species. Although the frequency of genes containing SSRs was slightly higher in Pinus taeda, SSR counts per Mbp for class I was similar in both species (P-value = 0.22); while for class II SSRs, it was significantly higher in Picea abies (P-value = 0.00009). AT-rich motifs were higher in abundance than the GC-rich motifs, within class II SSRs in both the species (P-values = 10(-9) and 0). With reference to class I SSRs, AT-rich and GC-rich motifs were detected with equal frequency in Pinus taeda (P-value = 0.24); while in Picea abies, GC-rich motifs were detected with higher frequency than the AT-rich motifs (P-value = 0.0005). Conclusions: Our study gives a comparative overview of the genome SSRs composition based on high confidence genes in the two recently sequenced and economically important conifers and, also provides information on functional molecular markers that can be applied in genetic studies in Pinus and Picea species

    An Explorative Study of the Methods used in Dendrochronology and its Applications

    Get PDF
    The science of dendrochronology involves the dating of tree rings and analysis of their annual growth rates. It is important to conduct field studies to determine what tree species in a given area are suitable for analysis. This project began by coring Acer plantanoides, Acer saccharinum, Acer saccharum, and Picea abies from the Fanshawe Conservation Area in London, Ontario. Each core was prepped using standard procedures and analyzed for the visibility of annual rings. The tree rings of Acer plantanoides and Acer saccharinum were inadequate for accurate dating, and thus, only Acer saccharum and Picea abies were used and included in this poster. Ring widths of Acer saccharum and Picea abies were measured using WinDENDRO™ and COFECHA was used to evaluate the correlations of annual ring widths across the cores of each species. The intercorrelations of Acer saccharum were 0.404 and 0.571 for Picea abies. A standardized chronology was created by ARSTAN to analyze and compare annual growth rates across both species. Acer Saccharum and Picea abies both differed in their annual growth rates and degree of variability. Acer Saccharum had lower annual variation and overall lower annual growth rates than Picea abies. This project can be further expanded upon to include climate correlations in an attempt to explain the difference in growth rates and variability

    Possibilities and limitations of vegetative propagation in breeding and mass propagation of Norway spruce

    Get PDF
    The use of vegetative mass propagation in practical forestry with Norway spruce (Picea abies (L.) Karst.) is limited at present, although its potential to deliver high genetic gains is obvious. The objective of this thesis was to study possibilities and limitations of vegetative propagation when applied in different parts of a breeding/mass propagation system for Norway spruce. Two vegetative propagation methods were studied: somatic embryogenesis and cutting propagation. Somatic embryogenesis was accompanied by losses of genotypes during the propagation process. The embryogenic response at proliferation and maturation was under family control, while germination was obtained for all families. Parental effects on proliferation and maturation were found for male parents but not for female. However, no correlations between embryogenic characters and breeding goal traits could be detected on parental level. Shortening of treatment with abscisic acid (ABA) during somatic embryo development gave pronounced positive effects on height growth of regenerated plants. An improved protocol, including five weeks ABA treatment and root development in liquid medium significantly improved performance of the resulting plants. The number of plants with lateral roots at the time of ex vitro transfer increased substantially with this protocol. Lateral roots at ex vitro transfer were shown to be a marker for good height growth and clonal uniformity during the next two years. Selection for height of cutting propagated clones in the nursery resulted in low responses in height after six years in field. The likely reason for this was low correlations between nursery traits and field traits. Genotype x environment interactions in the studied clonal test series varied from close to zero to more than 50% of the clone component. A tendency towards increased interaction components with age was obtained in one of the series. In situations with large genotype x environment interactions, clonal stability over sites should be included in the selection criteria

    Identifizierung von Haplotypen bei Pityogenes chalcographus (Col., Scolytidae) durch SSCP

    Get PDF
    Pityogenes chalcographus is a widely distributed spruce pest in Eurasia (KNIZEK et al. 2005). In 70ies, E. Führer studied the intraspecific variation of this spruce bark beetle and detected race differentiation among European populations based on crossing experiments (FÜHRER 1977), morphological characters FÜHRER 1978) and allozyme electrophoresis (RITZENGRUBER 1990). In order to verify the hypothesis differentiation, we analysed diverse European P. chalcographus populations using the Cytochrome Oxidase gene (COI) of the mitochondrial DNA. The complete COI gene of 96 individuals was sequenced. In facilitate the screening of the European populations, we applied a PCR-SSCP method. This polyacrylamide electrophoresis technique offers a sensitive but inexpensive, rapid and convenient method for detecting polymorphisms, reducing the amount of samples that require sequencing (SUNNUCKS et al. 2000).Der Kupferstecher Pityogenes chalcographus (Coleoptera, Scolytidae) gehört zu den am weitesten verbreiteten Borkenkäfern Europas. Käferpopulationen aus verschiedenen Gebieten Europas zeigten eine hohe Divergenz hinsichtlich der Nukleotidzusammensetzung des mitochondrialen Cytochrom Oxidase I Gens. Die Unterschiede betragen bis zu 2,26% zwischen einzelnen Herkünften. Die phylogenetische Auswertung der Sequenzen des kompletten Gens (1503bp) ergab einen 6-astigen Baum mit insgesamt 34 Haplotypen. Ausgehend von dieser Struktur wurden Primerpaare entworfen, um jeweils etwa 250 bp lange mutationsreiche Abschnitte des COI Gens zu amplifizieren. Die PCR Produkte wurden mittels Single Strand Conformation Polymorphism (SSCP) untersucht. Zwischen den einzelnen Haplotypen konnten zahlreiche Polymorphismen erkannt werden. Diese eignen sich als schnelles Werkzeug zum screening einzelner Individuen und verringern signifikant die Notwendigkeit klassischer Sequenzierreaktionen

    Differential photosynthetic adaptation between size-classes of Spruce and Fir juveniles help to explain the co-existence of the two species.

    Get PDF
    Background/Question/Methods &#xd;&#xa;_Abies sachalinensis_ (Sakhalin Fir) and _Picea glehnii_ (Glehn&#x2019;s Spruce) are major components of the sub-boreal forests of Hokkaido, Japan. Similar Spruce-Fir forests can be found in many other places in the northern hemisphere and will probably be impacted by global warming. Therefore, detailed knowledge of these species&#x2019; physiology and life-history strategies at different growth stages is important to understand present communities and to support reliable prediction of possible consequences of global climate change. &#xd;&#xa;Accordingly, the objective of this study was to establish relations between community dynamics, life-history strategies and photosynthetic adaptation of these species, on different developmental stages. &#xd;&#xa;The study is taking place on a sub-boreal forest plot in north Japan (N 44&#xba; 19&#x2019;, E 142&#xba; 15&#x2019;). Twenty shade-growing individuals of both species were divided into two height classes: seedlings, if height &#x3c; 50cm; and saplings, if height &#x3e; 100cm. The canopy coverage over each individual was assessed by analyzing hemispherical photography and average light incidence. Leaf pigments are being analyzed by chromatography. Light response curves and chlorophyll fluorescence are being measured seasonally, except in winter. Results are analyzed through General Linear Models. The study period was from spring 2009 to summer 2010. &#xd;&#xa;Results/Conclusions &#xd;&#xa;Results show an inversion of the photosynthetic adaptation between seedlings and saplings, and also between species. _Picea_ seedlings and _Abies_ saplings have greater total chlorophyll content and higher photosynthetic rates than _Picea_ saplings and _Abies_ seedlings. As a consequence, the superior competitor between similar sized individuals of both species appears to change between size-classes, with _Abies_ presenting higher photosynthetic rates at the sapling class and _Picea_ at the seedling class. Nevertheless, no significant growth has been observed in any of the groups until now. Results also disagree with some of the previously reported photosynthetic characteristics of these species, with _Picea_ seedlings displaying more traits usually associated with shade adaptation than _Abies_ seedlings.&#xd;&#xa

    A phytosociological survey of the boreal forest (Vaccinio-Piceetea) in North America

    Get PDF
    A survey of syntaxa of vegetation of North American boreal forests (class Vaccinio-Piceetea) is presented. This phytosociological survey, carried out combining the Braun-Blanquet method with numerical syntaxonomical analyses (cluster and correspondence analysis), describes the associations of the North American boreal forests, which have several species, varieties or vicariant species in common with their Eurasian counterparts, and can be placed in the class Vaccinio-Piceetea. By means of tabular and multivariate analyses, 2084 North American relevés were compared with 3273 relevés from European, Japanese and Korean boreal forest, to describe and typify 4 orders, 10 alliances and 37 associations. Diagnostic tables, ordination, clustering, and climatic, edaphic and biogeographical data were used to show floristic affinities among these syntaxa and interpret their distribution areas. Syntaxa were briefly characterized by their floristic composition, physiognomy, succession, zonation, and biogeographical distribution

    The importance of Silver fir (Abies alba Mill.) in comparison to spruce (Picea abies (L.) Karst.) and oak (Quercus petraea (Matt.) Liebl.) for arboreal Heteroptera communities in Bavarian forests

    Get PDF
    Heteropteran communities in the canopies of Silver fir (Abies alba) and spruce (Picea abies) were studied at three lowland and three mountainous sites throughout Bavaria using flight-interception traps. At one lowland site sampling was extended to oak (Quercus petraea). A significantly higher number of species and specimens occurred on fir when compared to spruce. Including all sampled species, numbers on fir were even higher than on oak. Excluding tourists, oak was most species rich. Results demonstrate that fir, spruce, and oak harbour distinct communities. While specific communities including several rare species (e.g. Actinonotus pulcher, Psallus punctulatus) were found on fir, mainly generalists were found on spruce. Pinalitus atomarius, Cremnocephalus alpestris, Phoenicocoris dissimilis and Orius minutus significantly preferred fir. Therefore, with an increased cultivation of fir in lieu of spruce, an increase in Heteropteran diversity can be expected

    Direct measurement of tree height provides different results on the assessment of LiDAR accuracy

    Get PDF
    open8noopenSibona, Emanuele; Vitali, Alessandro; Meloni, Fabio; Caffo, Lucia; Dotta, Alberto; Lingua, Emanuele; Motta, Renzo; Garbarino, MatteoSibona, Emanuele; Vitali, Alessandro; Meloni, Fabio; Caffo, Lucia; Dotta, Alberto; Lingua, Emanuele; Motta, Renzo; Garbarino, Matte
    corecore