Hojka  Kraigher

Dr. Hojka Kraigher

Head of Department for Forest Physiology and Genetics & the Research Programme P4-0107, LIFEGENMON Coordinator, Večna pot 2, SI-1000 Ljubljana, Slovenia

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 March 2005 in FEMS Microbiology Letters
Verified
Journal Article
Closed access
KCKatarina Cankar
Katarina Cankar
Hojka  KraigherHojka Kraigher
Hojka Kraigher
MRMaja Ravnikar
Maja Ravnikar
MRMaja Rupnik
Maja Rupnik
Endophytic bacteria from wooden plants and especially seed-associated endophytes are not well studied. Fresh seeds collected from four Norway spruce trees (Picea abies) from different locations in the Slovene subalpine region were surface-sterilised and dissected into a seed coat, embryo and endosperm. The presence of endophytes was detected by culturing methods and by direct amplification of the eubacterial 16S rDNA gene. Both approaches identified bacteria from genera Pseudomonas and Rahnella in the Norway spruce seeds. Both are known plant-associated bacteria with growth-promoting properties and biological control potential. We suggest that plant seeds could serve as a vector for transmission of beneficial bacteria.

15 November 2007 in Plant Biosystems
Verified
Journal Article
Open access
PCP. Cudlin
P. Cudlin
BKB. Kieliszewska-Rokicka
B. Kieliszewska-Rokicka
Maria  RudawskaMaria Rudawska
Maria Rudawska
Tine GrebencTine Grebenc
Tine Grebenc
OAOdair Alberton
Odair Alberton
TKT. W. Kuyper
T. W. Kuyper
Human-induced and natural stress factors can affect fine roots and ectomycorrhizas. Therefore they have potential utility as indicators of environmental change. We evaluated, through meta-analysis, the magnitude of the effects of acidic deposition, nitrogen deposition, increased ozone levels, elevated atmospheric carbon dioxide, and drought on fine roots and ectomycorrhizal (ECM) characteristics. Ectomycorrhizal colonization was an unsuitable parameter for environmental change, but fine root length and biomass could be useful. Acidic deposition had a significantly negative impact on fine roots, root length being more sensitive than root biomass. There were no significant effects of nitrogen deposition or elevated tropospheric ozone on the quantitative root parameters. Elevated CO2 had a significant positive effect. Drought had a significantly negative effect on fine root biomass. The negative effect of acidic deposition and the positive effect of elevated CO2 increased over time, indicating that effects were persistent contrary the other factors. The meta-analysis also showed that experimental conditions, including both laboratory and field experiments, were a major source of variation. In addition to quantitative changes, environmental changes affect the species composition of the ectomycorrhizal fungal community.

14 March 2019 in Forests
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Journal Article
Open access
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Srdjan StojnicSrdjan Stojnic
Srdjan Stojnic
Evangelia V. AvramidouEvangelia V. Avramidou
Evangelia V. Avramidou
BFBarbara Fussi
Barbara Fussi
MWMarjana Westergren
Marjana Westergren
SOSasa Orlovic
Sasa Orlovic
MKMonika Konnert
Monika Konnert
In the present paper we studied the genetic diversity and genetic structure of five Norway spruce (Picea abies (L.) Karsten) natural populations situated in Serbia, belonging to the southern lineage of the species at the southern margin of the species distribution range. Four populations occur as disjunct populations on the outskirts of the Dinaric Alps mountain chain, whereas one is located at the edge of Balkan Mountain range and, therefore, can be considered as ecologically marginal due to drier climatic conditions occurring in this region. Due to the negative effect of biotic and abiotic stress factors, the sustainability of these populations is endangered, making conservation of their genetic resources one of the key measures of Norway spruce persistence in Serbia under climatic changes. The insight on genetic diversity and genetic structure of the studied spruce populations can provide the information required for the initiation of programs aimed at the conservation and utilization of spruce genetic resources at the rear edge of species environmental limits. Norway spruce genetic variation and population genetic structure were estimated using eight EST-SSR markers. The results showed that mean expected heterozygosity was 0.616 and allelic richness 10.22. Genetic differentiation among populations was low (Fst = 0.007). No recent bottleneck effect or isolation by distance were detected. Bayesian clustering, obtained with STRUCTURE, grouped the populations into two genetic clusters, whereas UPGMA analysis distinguished three main groups approximately in line with the geographic area of occurrence. Based on the study results and the EUFORGEN Pan-European strategy for genetic conservation of forest trees, the establishment of additional dynamic gene conservation units must be considered in Serbia in order to protect the adaptive and neutral genetic diversity of the species.

8 August 2023 in Forest Ecology and Management
Verified
Journal Article
Open access
MMMilan Mataruga
Milan Mataruga
BCBranislav Cvjetković
Branislav Cvjetković
BCBart De Cuyper
Bart De Cuyper
IAIna Aneva
Ina Aneva
PZPetar Zhelev
Petar Zhelev
PVPedro Villar-Salvador
Pedro Villar-Salvador

25 February 2025 in New Phytologist
Verified
Journal Article
Open access
FBFlorian Barbi
Florian Barbi
TMTijana Martinović
Tijana Martinović
IOIñaki Odriozola
Iñaki Odriozola
AMAntonin Machac
Antonin Machac
AMAndrea Moravcová
Andrea Moravcová
PKPetr Kohout
Petr Kohout
Summary: Gradients in species diversity across elevations and latitudes have fascinated biologists for decades. While these gradients have been well documented for macroorganisms, there is limited consensus about their universality, shape and drivers for microorganisms, such as fungi, despite the importance of fungal diversity for ecosystem functions and services. We conducted a comprehensive survey of fungal species richness in forests across 17 elevational transects along a latitudinal gradient covering the continental scale of Europe. Diversity patterns along elevational and latitudinal gradients differed among fungal ecological guilds. Diversity of saprotrophs declined with elevation while ectomycorrhizal (ECM) fungal diversity peaked in mid‐elevations. Moreover, the diversity of root endophytic fungi increased with latitude but did not change with elevation. Bayesian species distribution modeling suggests that fungal diversity is structured by deterministic rather than stochastic drivers. Importantly, ECM fungal diversity pattern persists even after accounting for the effects of environmental conditions. These results suggest that environmental conditions differentially shape the diversity of fungal guilds along elevational and latitudinal gradients, but this goes beyond soil and climatic factors in the case of ECM fungi. This study paves the way toward a better understanding of fungal diversity gradients across elevations and latitudes, with possible implications for macroecological theory, conservation and management.

31 December 2009 in Anales del Jardín Botánico de Madrid
Verified
Journal Article
Open access
Tine GrebencTine Grebenc
Tine Grebenc
María P. MartínMaría P. Martín
María P. Martín
Hojka  KraigherHojka Kraigher
Hojka Kraigher
Several morphological species of the genus Hydnum L. are known to occur in Europe, but little molecular evidence exists to confirm the exact number and delimitation of the species. The present study seeks to investigate the genus Hydnum through sequence analysis of the nuclear ribosomal ITS regions and through morphological studies. The DNA sequences phylogenetic analysis revealed high diversity among the ITS region sequences in H. repandum (two clades) and H. rufescens (six clades) while the specimens of H. albidum, H. umbilicatum and H. ellipsosporum formed one and clearly separated clade per morphological species. Phylogenetic distances among the recognised species and the obtained morphologically unsupported clades are comparable and support the idea of several new, yet undescribed species. The intraspecific variability in the sequence data among phylogenetic species is generally low. Detailed morphological analysis of putative informative morphological characteristics could not support any of the observed non-monophyletic DNA-sequences clades within H. repandum or H. rufescens, and the proper use of names is not yet clear. Similar intraspecific variation has also been observed in many other ectomycorrhizal genera and could be explained by intensive speciation within variable groups under the influence of various factors (niche effect, ectomycorrhizal partner selection).