Maja Jurc

Origin identification of Pinus nigra populations in southwestern Europe using terpene composition variations

The geographical variation of terpenes of Pinus nigra populations from southwestern Europe was studied. Terpenes from the foliage of 16 populations from Corsica, Herault (France) and the East Pyrenees (France and Spain) were analyzed. A total of 42 terpenes were detected, with α-pinene the dominant monoterpene and germacrene-d and caryophyllene the dominant sesquiterpenes. The differences in quantitative content of selected compounds clearly divide populations into two basic geographical groups: on one side the populations from Herault and the East Pyrenees and on the other the populations from Corsica. β-Phellandrene and δ-cadinene have the greatest influence on this global discrimination. Some trees and populations show a similarity although they belong to different geographic locations. The similarity of some trees from Herault and the East Pyrenees and trees from Corsica points to their common origin (Corsica). Our results confirm the hypothesis that the afforestation of Herault and the East Pyrenees was also performed with black pine from Corsica.

Antibacterial Activity in Higher Fungi (Mushrooms) and Endophytic Fungi from Slovenia

Abstract Discovery and development of new antibiotics is still very important because of the constant appearance of drug-resistant pathogenic bacteria. The broth microdilution test was applied for screening of antibacterial activity in extracts of higher and endophytic fungi. Among tested extracts, three possessed significant antibacterial activity: extracts of mushrooms Amanita virosa. (Fr.) Bertill. (Amanitaceae) and Cortinarius praestans. Cordier (Cortinariaceae) against Pseudomonas aeruginosa. and Staphylococcus aureus., respectively, and extract of endophytic fungus Trucatella hartigii. (Tubeuf) Steyaert (Amphisphaeriaceae) against Enterococcus faecalis. and S. aureus.. The extract of Truncatella hartigii. was further analyzed by one- and two-dimensional thin-layer chromatography, and the position of the active compound was determined on the chromatogram.

Xylophagous entomofauna in branches of oaks (Quercus spp.) and its significance for oak health in the Karst region of Slovenia

Samples of dying branches from 121 trees of Quercus pubescens, Q. cerris, and Q. petraea were taken from 102 sites in Seslerio autumnalis-Quercetum petraeae and Ostryo-Quercetum pubescentis forests. After nine months’ rearing in eclectors, branches were cut to 20-cm sections, and signs of infestation as well as larvae and adult insects were noted. We analysed 395 sections of branches from Q. pubescens, 125 sections from Q. cerris, and 85 sections from Q. petraea. We found 44 adult insects: 45% were from the Cerambycidae family (Callimus angulatus ssp. angulatus, Poecilium alni, and Exocentrus adspersus), 18% were from the Scolytinae subfamily (Scolytus intricatus, Xyleborus dispar), 4% from the Buprestidae family (Coraebus florentinus), 4.5% from the Cleridae family (Tilloidea unifasciata), and 28.5% from other families. In addition, 145 larvae were found: 50% from the Cerambycidae family, 39% from the Buprestidae family, 4% from the Scolytinae subfamily, and 7% from other families. Significant difference in the abundance of adult insects and larvae with regard to the diameter of branch sections and the host species were found. 78% of dying branches showed signs of infestation. Species of the Buprestidae, Scolytinae, and Cerambycidae represent important factors in the decline in oak vitality in the lower Karst region of Slovenia.

Ophiostomatoid fungi associated with three spruce-infesting bark beetles in Slovenia

ContextOphiostomatoid fungi can severely affect the health and economic value of Norway spruce trees (Picea abies). Although the diversity of ophiostomatoid species and their associations with insects have been well-investigated in central and northern Europe, little is known about the conditions in south-eastern Europe.AimThis study aims to study the assemblages of ophiostomatoid fungi associated with three bark beetle species (Ips typographus, Ips amitinus, and Pityogenes chalcographus) that infect Norway spruce in Slovenia.MethodsBark beetles were sampled in four phytogeographic regions in Slovenia. The fungi found on the bark beetles were identified based on morphology, DNA sequence comparisons of ITS regions and phylogenetic analysis. The species compositions of the fungal associates of the three insect species were compared and the pairwise associations of the occurrence of the fungal species were analysed.ResultsThirteen different species were found. The most commonly encountered fungal associates of the beetles were Ophiostoma bicolor, Ophiostoma brunneo-ciliatum, Grosmannia piceiperda, Ophiostoma ainoae, Ceratocystiopsis minuta, and Grosmannia penicillata. The composition of the fungal associates differed among the bark beetle species, but not among the phytogeographic regions.ConclusionsThis study confirms that ophiostomatoid species are common associates of the investigated bark beetle species. Many ophiostomatoid species have strong host associations. I. typographus and P. chalcographus can act as effective vectors for O. bicolor, O. ainoae, G. piceiperda and O. brunneo-ciliatum, whereas I. amitinus often carries G. piceiperda and C. minuta in Slovenian forests.

Climate Warming and Past and Present Distribution of the Processionary Moths (Thaumetopoea spp.) in Europe, Asia Minor and North Africa

Pine processionary moth, Thaumetopea pityocampa, is a model insect indicator of global warming, the northwards and upwards range expansion of this Mediterranean species being directly associated with the recent warming up. The knowledge about the drivers of moth expansion is synthesized. A first standardized mapping of the northern expansion edge, from Western Europe to Turkey, is presented, then detailed for 20 countries of Europe, Asia Minor and North Africa, including future trends. Additional data about the responses of the other Thaumetopoea species are given. Finally, the chapter points out the importance of the man-mediated introductions in the expansion process.

The attraction of cerambycids and other xylophagous beetles, potential vectors of Bursaphelenchus xylophilus, to semio-chemicals in Slovenia

The attractiveness of different semio-chemicals to potential vectors of the phytoparasitic nematode Bursaphelenchus xylophilus was investigated in conifer forests in Slovenia. From 2007 to 2009, the presence of xylophagous beetles in Pinus nigra, P. sylvestris, P. halepensis, Picea abies and Abies alba stands was assessed at eight locations. Insects were collected at 1-month intervals during the growing season using four cross vane traps per location with a collecting container with propylene glycol and attractants (ethanol+α-pinene, Pheroprax® and Gallowit®). The trapped insects represented 24 families of the order Coleoptera, and we identified 94 species. The most numerous group was the weevil subfamily Scolytinae (76.55% of all insects collected), followed by the family Cerambycidae (8.12%), and the weevil subfamily Curculioninae (1.67%). With regard to species number, the most frequent wood-borers were Cerambycidae (24 taxa), Scolytinae (12 species) and Buprestidae (8 species). The most abundant species was Spondylis buprestoides, followed by Arhopalus rusticus, Monochamus galloprovincialis and Arhopalus ferus. At all locations, the largest catch of Cerambycidae occurred in July. The most effective attractant was ethanol+α-pinene, followed by Gallowit®; the least effective attractant was Pheroprax®. Among Monochamus species, M. galloprovincialis represented 17.54%, M. sutor 0.09% and M. sartor 0.04% of the long-horned beetles collected. Monochamus individuals were most numerous in the P. nigra stand and were attracted in the greatest numbers by Gallowit®, followed by ethanol+α-pinene. The cerambycid catch was highly correlated with the catch of non-target bark beetle predators (Cleridae, Staphylinidae, Histeridae, Trogositidae, Nitidulidae, Rhizophagidae) in the traps.

Phoretic mites of the six-spined engraver beetle, Ips sexdentatus (Böerner, 1776) (Coleoptera, Scolytinae), on Pinus halepensis in Slovenia

In September 2009, specimens of Ips sexdentatus were captured using black cross vane traps in an old stand of Pinus halepensis Miller at Dekani in the submediterranean ecological region of Slovenia. Twenty-four per cent of them carried phoretic mites, and six taxa of mites were collected directly from their bodies: Cercoleipus coelonotus, Dendrolaelaps quadrisetus, Histiostoma ovalis, Trichouropoda polytricha, Uroobovella varians and Vulgarogamasus lyriformis. All of these species are documented here for the first time as associated with the six-spined engraver beetle in Slovenia. Both D. quadrisetus and V. lyriformis are predatory on bark beetle eggs and larvae and could be useful in biological control programmes. Moreover, H. ovalis may be an important vector of fungal spores of ophiostomatoid pathogenic fungi. urn:lsid:zoobank.org:pub:B3E36510-4687-42B8-BDCC-3912A2AB9EE0

Target and non-target beetles in semiochemical-baited cross vane funnel traps used in monitoring Bursaphelenchus xylophilus (PWN) vectors in pine stands

In 2007–2012 we assessed dendrobiotic insects at three locations in stands of Pinus nigra, Pinus halepensis and Pinus sylvestris in Slovenia. The samples were collected from May to November using four (three in 2007) cross vane funnel traps per location with wet collecting cups and attractants. In 2007 we used ethanol+α-pinene, and from 2008 to 2010, ethanol+α-pinene, Pheroprax® (ipsdienol, cis-verbenol, 2-methylbut-3-en-2-ol) and Gallowit® (ipsdienol CAS 14434-41-4, ipsenol CAS 60894-96-4, DMWK CAS 115-18-4, cis-verbenol CAS 18881-04-4, α-pinene CAS 80-56-8, ethanol CAS 64-17-5) were used with traps 1.5 m above the ground. In 2011–2012 ethanol+α-pinene and Galloprotect 2D® (Galloprotect F: an aggregation pheromone [2-undecyloxy-1-ethanol] and Galloprotect A: kairomonal substances [ipsenol and 2-methyl-3-buten-1-ol]) were used with traps in the lower canopy. We collected 31,228 individuals from 45 beetle families. Curculinidae (Scolytinae, 23,325) were the most numerous, and the target family Cerambycidae was represented with 1945 specimens from 28 taxa and 25 species. In 2007 Spondylis buprestoides was by far the most abundant species. In 2008–2010 ethanol+α-pinene more effectively attracted S. buprestoides and A. rusticus, whereas Monochamus galloprovincialis showed a clear preference for Gallowit®. In 2011–2012 Galloprotect 2D® attracted significantly more cerambycids than ethanol+α-pinene, and M. galloprovincialis was by far the most numerous species. In addition to cerambycids, other saproxylic beetle species and also scolytine predators (mostly Cleridae, Histeridae, Trogossitidae) were found in the traps, highlighting the need to consider the potential negative impacts of the long-term monitoring of PWN vectors on species with important functional-trophic traits in forests.

Essential-Oil Variability in Natural Populations of Pinus mugo Turra from the Julian Alps.

The composition and variability of the terpenes and their derivatives isolated from the needles of a representative pool of 114 adult trees originating from four natural populations of dwarf mountain pine (Pinus mugo Turra) from the Julian Alps were investigated by GC‐FID and GC/MS analyses. In total, 54 of the 57 detected essential‐oil components were identified. Among the different compound classes present in the essential oils, the chief constituents belonged to the monoterpenes, comprising an average content of 79.67% of the total oil composition (74.80% of monoterpene hydrocarbons and 4.87% of oxygenated monoterpenes). Sesquiterpenes were present in smaller amounts (average content of 19.02%), out of which 16.39% were sesquiterpene hydrocarbons and 2.62% oxygenated sesquiterpenes. The most abundant components in the needle essential oils were the monoterpenes δ‐car‐3‐ene, β‐phellandrene, α‐pinene, β‐myrcene, and β‐pinene and the sesquiterpene β‐caryophyllene. From the total data set of 57 detected compounds, 40 were selected for principal‐component analysis (PCA), discriminant analysis (DA), and cluster analysis (CA). The overlap tendency of the four populations suggested by PCA, was as well observed by DA. CA also demonstrated similarity among the populations, which was the highest between Populations I and II.