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Nicholls J.A.,University of Edinburgh | Fuentes-Utrilla P.,University of Edinburgh | Hayward A.,University of Edinburgh | Hayward A.,University of Oxford | And 7 more authors.
BMC Evolutionary Biology | Year: 2010

Background: Biological invasions provide a window on the process of community assembly. In particular, tracking natural enemy recruitment to invading hosts can reveal the relative roles of co-evolution (including local adaptation) and ecological sorting. We use molecular data to examine colonisation of northern Europe by the parasitoid Megastigmus stigmatizans following invasions of its herbivorous oak gallwasp hosts from the Balkans. Local host adaptation predicts that invading gallwasp populations will have been tracked primarily by sympatric Balkan populations of M. stigmatizans (Host Pursuit Hypothesis). Alternatively, ecological sorting allows parasitoid recruitment from geographically distinct populations with no recent experience of the invading hosts (Host Shift Hypothesis). Finally, we test for long-term persistence of parasitoids introduced via human trade of their hosts' galls (Introduction Hypothesis). Results: Polymorphism diagnostic of different southern refugial regions was present in both mitochondrial and nuclear microsatellite markers, allowing us to identify the origins of northern European invaded range M. stigmatizans populations. As with their hosts, some invaded range populations showed genetic variation diagnostic of Balkan sources, supporting the Host Pursuit Hypothesis. In contrast, other invading populations had an Iberian origin, unlike their hosts in northern Europe, supporting the Host Shift Hypothesis. Finally, both British and Italian M. stigmatizans populations show signatures compatible with the Introduction Hypothesis from eastern Mediterranean sources. Conclusions: These data reveal the continental scale of multi-trophic impacts of anthropogenic disturbance and highlight the fact that herbivores and their natural enemies may face very different constraints on range expansion. The ability of natural enemies to exploit ecologically-similar hosts with which they have had no historical association supports a major role for ecological sorting processes in the recent assembly of these communities. The multitude of origins of invading natural enemy populations in this study emphasises the diversity of mechanisms requiring consideration when predicting consequences of other biological invasions or biological control introductions. © 2010 Nicholls et al; licensee BioMed Central Ltd.


Borovics A.,Hungarian Forest Research Institute | Matyas C.,University of West Hungary
Annals of Forest Science | Year: 2013

Context: Genetic diversity of sessile oak (Quercus petraea) populations in Hungary was assessed close to the retracting, low-elevation, low-latitude (xeric) distribution limits. Objective: We aimed at tracing an assumed effect of climatic factors on genetic diversity, particularly at the southern, low elevation limits of distribution. Methods: Genetic diversity at isozyme-coding loci was analysed in populations, and related to the climate of the sites where the populations grow. A locus-wise analysis proved to be essential to follow responses. Results: A climate-related cline was found at seven isoenzyme-coding gene loci. Declining allelic numbers and heterozygosity indicated lower diversity at warmer and drier sites. The majority of loci were responsive to precipitation factors, others to temperature. Genetic clustering was neither related to geographic distance nor to random or historic effects. Conclusions: The results suggest that climatic stress may elicit a genetic diversity loss in populations, which may reduce their plasticity and adaptive potential. The selective pressure may override historic effects and gene flow. With respect to expected climate change, the correlation of diversity with some climatic factors gains specific importance. If supported by further investigations, the results might be utilised for reconsidering conservation strategies and rules for use of forest reproductive material. © 2013 INRA and Springer-Verlag France.


Toth T.,Research and Extension Center for Fruit Growing | Lakatos T.,Nemaform Ltd | Koltay A.,Hungarian Forest Research Institute
International Journal of Systematic and Evolutionary Microbiology | Year: 2013

Seven Gram-negative bacterial strains were isolated from oozing bark canker of poplar (Populus×euramericana) trees in Hungary. They showed high (.98.3 %) 16S rRNA gene sequence similarity to Lonsdalea quercina; however, they differed from this species in several phenotypic characteristics. Multilocus sequence analysis based on three housekeeping genes (gyrB, atpD and infB) revealed, and DNA-DNA hybridization analysis confirmed, that this group of bacterial strains forms a distinct lineage within the species Lonsdalea quercina. A detailed study of phenotypic and physiological characteristics confirmed the separation of isolates from poplars from other subspecies of L. quercina; therefore, a novel subspecies, Lonsdalea quercina subsp. populi, type strain NY060T (5DSM 25466T=NCAIM B 02483T), is proposed. © 2013 IUMS.


Redei K.,Hungarian Forest Research Institute | Keser Z.,Hungarian Forest Research Institute
Acta Silvatica et Lignaria Hungarica | Year: 2012

The fact that certain ecological factors fundamentally influencing tree growth have become unfavourable in Hungary in recent years, has led to the more extensive use of white poplar (and its hybrids) in afforestation and forest regeneration. An intensive integrated research and development work has been carried out on the growth of Leuce poplars on sandy soils, including primarily the white poplar (Populus alba) and its natural hybrid the grey poplar (Populus x canescens). The research revealed several factors influencing stand growth. The study presents a new, simplified tending operation model for Leuce poplar stands, as well as age, growing space and target diameter models suitable for qualitaty log production and for mass assortments. The simplicity of these practice-oriented models may foster the qualitative development of Leuce poplar management in Hungary.


Dani M.,University of West Hungary | Farkas A.,University of Pécs | Cseke K.,Hungarian Forest Research Institute | Filep R.,University of Pécs | Kovacs A.J.,University of West Hungary
Plant Systematics and Evolution | Year: 2014

Leaf epidermal (micromorphological and micromorphometric) features of the leaf blade were examined with light and scanning electron microscopy in 49 Central European natural populations of species belonging to subgenera Schedonorus and Drymanthele within the genus Festuca L. In addition, molecular biological (random amplified polymorphic DNA) studies were conducted on selected populations. The goal of the study was to reveal the degree of anatomical and genetic variability at the taxon and population level, as well as to determine the most important characters that allow differentiation of the taxa in these two subgenera. The anatomical variation was compared with the genetic distance between taxa. Investigated taxa exhibited great anatomic variability in terms of both qualitative (presence or absence, shape and appearance of various cell types) and quantitative characters (frequency and size of cells). Strong correlation was found between the genetic distance of populations and the frequency and size of silica cells in the costal zone of the epidermis, which indicates that silica cells are largely determined by the genetic background, regardless of varying environmental conditions. Our studies highlight that despite the high level of variability in anatomical features and genetic polymorphism, these fescue populations clearly segregate both in terms of epidermal structure and genetic constitution. © 2013 Springer-Verlag Wien.


Acs Z.,Systematic Parasitoid Laboratory | Challis R.J.,University of Edinburgh | Challis R.J.,University of York | Bihari P.,Hungarian Academy of Sciences | And 11 more authors.
Molecular Phylogenetics and Evolution | Year: 2010

We examine phylogenetic relationships within the Synergus complex of herbivorous inquiline gallwasps (Hymenoptera; Cynipidae; Synergini) associated with cynipid host galls on oak, a biologically diverse group whose genus-level morphological taxonomy has long been considered stable but whose species level taxonomy is problematic. We incorporate data for over 70% of recognised Western Palaearctic species in five morphology-based genera (Ceroptres, Saphonecrus, Synergus, Synophrus, Ufo), comprising sequence for two mitochondrial loci (coxI, cytb) and one nuclear locus (28S D2). In particular, we assess the evidence for monophyly of two long-established, morphology-defined sections within the genus Synergus that differ in a range of biological traits. To aid analyses of ecological interactions within oak cynipid communities, we also consider the utility of cytochrome oxidase I (coxI) DNA barcodes in the oak inquilines. In this assessment, we do not assume that species are delineated at a single threshold value of sequence divergence for a single gene, but examine concordance in the composition of molecular operational Taxonomic units (MOTUs) across a range of sequence divergences in each gene and across genes. We also assess the impact of sampling effort on MOTU stability. Phylogenetic reconstructions for all three loci support monophyly for Synergus and Synophrus, but reject monophyly for Saphonecrus and for the two sections within Synergus. The suites of traits associated with the two sections of the genus Synergus are thus homoplasious. All three loci also reject monophyly for three Synergus species (S. hayneanus, S. pallipes, S. umbraculus). Sequences for each locus identify robust MOTUs that are largely concordant across loci for a range of cut-off values. Though many MOTU's correspond to recognised Linnean species, there is significant, multigene disagreement between groupings supported by morphology and sequence data, with both allocation of different morphospecies to the same MOTU and allocation of the same morphospecies to multiple MOTUs, regardless of cut-off value. Our results imply that while DNA barcoding has considerable utility within this group, morphology-based identification needs major revision at both genus and species levels. Further, lifehistory traits currently attributed to single morphospecies probably confound attributes of multiple lineages. Revealing patterns of character state evolution in Synergus requires collection of new host association and life history data explicitly linked to DNA barcode data for the specimens concerned. Crown Copyright © 2009.


Nicholls J.A.,University of Edinburgh | Preuss S.,University of Edinburgh | Hayward A.,University of Edinburgh | Hayward A.,University of Oxford | And 7 more authors.
Molecular Ecology | Year: 2010

Little is known about the evolutionary history of most complex multi-trophic insect communities. Widespread species from different trophic levels might evolve in parallel, showing similar spatial patterns and either congruent temporal patterns (Contemporary Host-tracking) or later divergence in higher trophic levels (Delayed Host-tracking). Alternatively, host shifts by natural enemies among communities centred on different host resources could disrupt any common community phylogeographic pattern. We examined these alternative models using two Megastigmus parasitoid morphospecies associated with oak cynipid galls sampled throughout their Western Palaearctic distributions. Based on existing host cynipid data, a parallel evolution model predicts that eastern regions of the Western Palaearctic should contain ancestral populations with range expansions across Europe about 1.6 million years ago and deeper species-level divergence at both 8-9 and 4-5 million years ago. Sequence data from mitochondrial cytochrome b and multiple nuclear genes showed similar phylogenetic patterns and revealed cryptic genetic species within both morphospecies, indicating greater diversity in these communities than previously thought. Phylogeographic divergence was apparent in most cryptic species between relatively stable, diverse, putatively ancestral populations in Asia Minor and the Middle East, and genetically depauperate, rapidly expanding populations in Europe, paralleling patterns in host gallwasp species. Mitochondrial and nuclear data also suggested that Europe may have been colonized multiple times from eastern source populations since the late Miocene. Temporal patterns of lineage divergence were congruent within and across trophic levels, supporting the Contemporary Host-tracking Hypothesis for community evolution. © 2010 Blackwell Publishing Ltd.


Redei K.,Hungarian Forest Research Institute | Csiha I.,Hungarian Forest Research Institute | Kesero Z.,Hungarian Forest Research Institute
Acta Silvatica et Lignaria Hungarica | Year: 2011

The improvement of the reliability of renewable resources and the decline in reserves of fossile raw material in the coming decades will lead to increasing demands for wood material and consequently to a greater role of short rotation forestry (SRF). Particular efforts have been made in Europe to substitute fossils with renewables, in this context the proportion of renewable energy should be increased to 20% by 2020. SRF can be provide relatively high dendromass (biomass) increment rates if the short rotation tree plantations are grown under favourable site conditions and for an optimum rotation length. However, in many countries only so-called marginal sites are available for setting up tree plantations for energy purpose. For SRF under marginal site conditions black locust (Robinia pseudoacacia L.) can be considered as one of the most promising tree species thanks to its favourable growing characteristics. According to a case study presented in the paper black locust can produce a Mean Annual Increment (MAI) of 2.9 to 9.7 oven-dry tons ha -1 yr -1 at ages between 3 and 7 years using a stocking density of 6667 stems ha -1. On the base of the presented results and according to international literature the expected dendromass volume shows great variation, depending upon site, species, their cultivars, initial spacing and length of rotation cycle.


Somogyi Z.,Hungarian Forest Research Institute | Bidlo A.,University of West Hungary | Csiha I.,Hungarian Forest Research Institute | Illes G.,Hungarian Forest Research Institute
European Journal of Forest Research | Year: 2013

International agreements require countries to annually report on greenhouse gas emissions and removals. For the land-use sector, this includes estimating stock changes in various carbon pools. For carbon pools like mineral forest soil where a country-level statistical inventory based on measurements is very difficult, models are usually applied together with data from case studies. In this paper, we present a country-specific model together with case studies that aim at capturing major soil processes due to forestry activity. These processes include "hot moments", e.g., disturbances that occur rarely but might result in relatively high emissions. The model only aims at developing a conservative estimate, rather than a central one, of net country-level carbon stock change with emissions overestimated and removals underestimated. The model is partially parameterised using paired sampling of soil organic carbon in the uppermost 30-cm layer, applying standard methods including those suggested by IPCC, in afforestations on former croplands and in artificial regenerations. Results show that soils of afforested croplands act as a sink, and carbon stock after regeneration might decrease due to disturbance by forest operations, but might also increase due to transfer of carbon from dead roots to soil depending on disturbance levels. The estimation at the country level, which involves additional considerations and data from the literature, suggests that overall, forest soils are a net sink in Hungary, but also that artificially limiting soil organic carbon changes estimation to the uppermost 30-cm layer as applied in the IPCC methodology might lead to artefacts. © 2013 Springer-Verlag Berlin Heidelberg.


Pasztor L.,Hungarian Academy of Sciences | Szabo J.,Hungarian Academy of Sciences | Bakacsi Zs.,Hungarian Academy of Sciences | Laborczi A.,Hungarian Academy of Sciences | And 3 more authors.
GlobalSoilMap: Basis of the Global Spatial Soil Information System - Proceedings of the 1st GlobalSoilMap Conference | Year: 2014

The main objective of the DOSoReMI.hu (Digital, Optimized, Soil Related Maps and Information in Hungary) project is to significantly extend the potential, how demands on spatial soil related information could be satisfied in Hungary. Although a great amount of soil information is available due to former mappings and surveys, there are more and more frequently emerging discrepancies between the available and the expected data. The gaps are planned to be filled with optimized DSM products heavily based on legacy soil data, which still represent a valuable treasure of soil information at the present time. Our paper presents the first pilot results achieved for Zala County, Hungary: the identified effects of DSM components on the accuracy of a specific output map; together with some modest proposals for their applicability in the optimization of the whole mapping process. © 2014 Taylor & Francis Group, London, UK.

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