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The East Asian ambrosia beetle (Xylosandrus germanus - Blandford 1894) is an invasive species that has become successfully established in Europe and North America. In Slovenia, X. germanus was first recorded in 2000 in the western part of the country, and since 2008 the species has also been identified in other parts of Slovenia. The first economic damage was recorded in 2016 after a massive attack on recently felled logs of different tree species, spurring research into this non-native invasive species. To examine the distribution and abundance of X. germanus compared to other ambrosia beetles and to determine voltinism and the flight period of the species in our climatic conditions, we deployed 19 ethanol-baited traps from March to November 2017 in oak-, beech- and fir-dominated forest stands in central Slovenia. To verify the vertical distribution of X. germanus, traps were installed at altitudes ranging from 303 m to 941 m a.s.l. Furthermore, the impact of the ice storm that hit Slovenia in 2014 on the abundance of X. germanus was also studied. Non-native X. germanus represented 71.8% of the total catch and was significantly more abundant than the other five most common species: Xyleborinus saxesenii (20.0%), Xyleborus monographus (3.6%), Anisandrus dispar (2.5%), Trypodendron domesticum (1.2%) and Trypodendron signatum (0.6%). X. germanus was most abundant in beech-dominated stands, but the differences between forest types were not significant. The species was found along the entire altitudinal gradient. Our results indicate that the swarming of X. germanus in lowland forests may already occur by the middle of March. Maximum flying activity was observed in May and early June in forests below 600 m a.s.l. and at the end of May and in June in forests above 700 m a.s.l. Only one generation per year was observed. The ice storm positively affected the abundance of X. germanus, especially in areas where sanitary logging was delayed. Xyleborinus attenuatus was detected for the first time in Slovenia.

The purpose of the study was to develop, calibrate and validate a comprehensive phenological model for the spatiotemporal simulation of the seasonal development of the six-toothed spruce bark beetle, Pityogenes chalcographus (CHAPY). The validation dataset was acquired through monitoring of the bark beetle's phenology at eight sites in Slovenia in 2017 and 2018, along with air and bark temperature measurements. The predictions were made using air temperature from the INCA system (Integrated Nowcasting through Comprehensive Analysis), which is used to calculate the effective bark temperature for beetle development. Since the biology of P. chalcographus is poorly studied, a sensitivity analysis was used to pinpoint the most important model parameters. The first order (main) effect was the highest for the lower developmental threshold (DTL), while the second order (interaction, total) effect was the highest for the optimum temperature (TO). DTL was calibrated with an iterative procedure, and the best result with the lowest mean absolute error (MAE) was achieved at 7.4°C. Effective temperatures in the range between TO and the upper developmental threshold were calculated with a nonlinear function whose parameters were appropriately calibrated. The spring date threshold when the model calculation starts was calibrated with an iterative procedure and set at 9th March, which had the minimum MAE. The onset of Norway spruce infestation in spring was estimated using a lower threshold of 15.6°C for flight activity and a mean thermal sum of 216.5 degree-days (dd) from 9th March onward. The observed mean thermal sum required for total development of filial beetles was 652.8 ± 22.7°C, while the predicted mean thermal sum was 635.4 ± 31.4°C. Re-emergence of parental beetles occurred when 52.7% of the minimum thermal sum for total development was reached. The relative duration of the egg, larval and combination of the pupal and teneral adult developmental stages was 9.4%, 58.2% and 32.4%, respectively. Mass swarming concluded in the end of August when daylength was lower than 13.6 h, which was determined with the independent dataset of 1,017 pheromone traps. The diapause initiation at a daylength

International audience; The North American oak lace bug feeds on leaves of 'white oaks" in its native range. In Europe, it was first discovered in northern Italy in 2000. In recent years, it has subsequently spread rapidly and population outbreaks have been observed in several European countries. In the present study, we summarize the steps of its expansion. To predict its potential host range, we checked 48 oak species in 20 sentinel gardens in seven countries between 2013 and 2018. In total, 27 oak species were recorded as suitable hosts; 13 of them are globally new ones, 23 out of the 29 in section Quercus (similar to white oaks, an intrageneric taxonomic unit within genus Quercus), including Asian oaks, native to Japan, Korea and China, and four out of five in section Cerris (another intrageneric unit of the same genus), were accepted as hosts. None of the species in section Lobatae (red oaks) or in the Ilex group was accepted. Host records were also collected in forest stands of 10 countries. We found 11 oak species that were infested. Outbreak populations were most commonly found on Quercus robur, Quercus frainetto, Quercus petraea and Quercus cerris, comprising widespread and outstandingly important oaks species in Europe. Based on our findings, we conclude that suitable hosts for oak lace bug are present in most of Europe and Asia. This means that a lack of hosts will likely not restrict further range expansion.

Parasitoids are known to be an important factor in the population density regulation of bark beetles. In our study of the parasitoid complex of spruce bark beetles in 2011 and 2012, we collected bark samples from trees infested with I. typographus from spruce stands in the altimontane belt of Slovenia. The samples were taken at different altitudes: 450, 700 and 1230 m above sea level. A total of 9 bark beetle species and 12 parasitoid species was found. Ips typographus was most abundant, with 93% of all species of scolytids. The parasitoid species that were found belonged mainly to the Pteromalidae and Braconidae families. By far the most abundant and frequent species was Roptrocerus xylophagorum, which represented 84% of all parasitoids and was present in all study samples. Differences in species composition, parasitoid species diversity, species abundance and parasitism rate were confirmed between locations and also between both years of our study.

We survey non-native insects species in whole territory of Slovenia. Data on non-native species were collected in field, and we also used results of projects in which we participated and with overview of literature data in scientific pub-lications. Correspondence Analysis (CA) of data was carried out with the soft-ware Statgraphics Centaurion XVI, U.S.A. Up to 254 non-native insect species are present: around 83% are phytophagous (43% feed on woody plants, 40% on other plants); around 12% are non-phytophagous; and 5% are parasitoids or predators of other insects or mammals. Among the phytophagous species, Hemiptera predominates (with 38.2%), followed by Coleoptera (29.8%) and Lepidoptera (14.5%). Non-native insects that do not feed on plants include Coleoptera (80%), Lepidoptera (6.5%), Hymenoptera (6.5%) and Diptera (6.5%). Most of phytophagous species are associated with introduction of plants on which they are specialists, but some have also shifted from introduced to native plant hosts. 36 non-native phytophagous species (14.17% of all non-native insects) have become harmful plant pests of urban trees and crops. 20 appear on woody plants, but only Dryocosmus kuriphilus, appears in urban forest areas. In the past decades species such as D. kuriphilus, Leptoglossus occidentalis, Xylosandrus germanus, Gnathotrichus materiarius, Dasineura gledichiae, Phyllonorycter issikii, Cinara curvipes, Ophiomyia kwansonis have been recorded in parks and forests. Some non-native species are spreading in Slovenian urban forests and affect economic, ecological and other forest and urban forest functions. The number of harmful insects in forests is extremely small probably due to high diversity of the forest ecosystem, where close-to-nature forest management is practiced, which retains forest’s self-regulatory ability to control pests. Such management enables for example the reduction of D. kuriphilus with expansion of its parasitoid, Torymus sinensis. We attempt to explain this phenomenon: we assume that T. sinensis was introduced in Slovenia as diapaused eggs in its host, D. kuriphilus.

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.

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 mugoTurra) 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 -car-3-ene, -phellandrene, -pinene, -myrcene, and -pinene and the sesquiterpene -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. Ministry of Education and Science of Republic of Serbia {[}173011, 173021]; Slovenian Research Agency {[}P4-0107, P4-0059]

We developed the RITY-2 phenology model for the spatial and temporal simulation of the seasonal development of Ips typographus based on the PHENIPS model and the data of Integrated Nowcasting through Comprehensive Analysis (INCA). Many parts of PHENIPS were improved with innovative approaches and a new model was developed. European spruce bark beetle phenology was monitored at eight study sites in 2017 and 2018, along with air and bark temperature measurements. RITY-2 predictions are based on air temperature from the INCA system, which is used to calculate the effective bark temperature for beetle development. An innovative procedure was introduced which finds most appropriate spring threshold from which calculation of the phenological model initiates. The onset of Norway spruce infestation in spring was estimated using a lower threshold of 14.5 °C for flight activity and a mean thermal sum of 53.0 degree-days (dd) from 7th March onward. The rate of brood development was calculated from the cumulative effective thermal sum of 30-min temperature data using upper and lower temperature thresholds of 38.9 and 8.3 °C, respectively, and a nonlinear function. For validation, we compared the timing of phenological events in the field with predicted events using both 30-minute recorded data from trap logs in the field and hourly data from INCA. The onset of spring swarming was estimated with a mean absolute error of 2.4 days. The onset of infestation was predicted with a mean absolute error of 4.7 days. The observed onset of emergence of filial beetles was estimated with a mean error of 0.5 dd. The model is calculated according to three scenarios that simulate different stand conditions. RITY-2 explicitly considers the strong effects of regional topography and can be used for precise monitoring of the actual state of bark beetle development at the specific model cell with a spatial resolution of 1 km × 1 km. Additionally, RITY-2 simulates the number of generations, which is necessary to assess the potential impact of bark beetle outbreaks at the regional scale. The model was successfully incorporated into two web applications that serve as tools for the timely deployment of pheromone traps and trap trees for European spruce bark beetle monitoring. The possible application of the RITY-2 model for the whole of Central Europe using data from the INCA system is discussed.

PCR-RAPD markers revealed individual variation in F. ornus. A total of 122 fragments were amplified using 7 primers and of these 97 fragments were polymorphic. The percentage of polymorphic loci was between 53.3% and 74.6% with an average of 63.1%. The mean gene diversity for all populations was 0.30 and the mean Shannon’s index was 0.44. Of the total genetic variation 87% was intra-population whilst 13% was inter-population. The Mantel test revealed significant correlation between genetic and geographical distance matrice. Results herein represent the first use of molecular genetic (DNA) markers to characterize genetic variation in F. ornus populations. The partition of total genetic variance indicates a relatively restricted population differentiation as expected in outcrossing species. Present and future information on genetic structure and variability in F. ornus needs to be incorporated into strategies for the preservation of genetic resources of tree species. [Projekat Ministarstva nauke Republike Srbije, br. 173011]

O nalazu hrastove mrežaste stjenice (Corythucha arcuata) u parku dvorca Lužnica kod Zaprešića, Hrvatska, 6 km od slovenske granice, obavijestio nas je prof. Boris Hrašovec sa Šumarskog fakulteta Sveučilišta u Zagrebu u jesen 2016. godine. 17. 11. 2016 obavili smo potragu za štetnikom na sedam lokacijama u jugoistočnoj Slove­niji (Mokrice, Obrežje, Rigonce, Dobova, Mostec, Zakot i Bukošek). Pričvršćeno i djelomično zeleno lišće, kao i otpalo lišće Quercus robur je bilo na terenu pomno pregledano i sumnjivi uzorci su stavljeni u plastične vrećice i donijeti u laboratorij za daljnju analizu. Morfološka identifikacija je provedena na uzorku jajnih grupa na do­njoj strani lišća i svlakova ličinki (exuviae) koje su bile prisutni na otpalom lišću Q. robur. Izvršeno je mjerenje broja jaja u 9 jajnih grupa i dužina i širina 30 jajnih čahura. Jajne ljuske (čahure) i svlakovi ličinaka na otpalom lišću Quercus robur bile su na pretraženom području nađene samo u hrastovoj šumi kod sela Zakot u blizini Brežica (E, 45°54’48“ N), koji je 14 km od najbližjeg nalaza u Hrvatskoj kod dvorca Lužnica. Jajne grupe sadržale su od 12 do 61 jajnih čahura. Jajne čahure su bile vretenastog oblika i crna s apikalnim otvorom i rubnim zadebeljenjem, duge 560 μm (475-596 μm) i široke 196 μm (183-196 μm). Ličinke su bile uglavnom tamne sa prozirnim žućkastim dijelovima na obje strane tijela. Imale su brojne bodlje. Brojne katranasto crne mrlje izmeta (faeces) hrastove mrežaste stjenice nalazile su se ravnomjerno na donjoj površini hrastovog lišća na kojem su bile prisutne jajne čahure i svlakovi ličinki. C. arcuata najvjerovatnije se proširila u Sloveniju iz Hrvatske, gdje je bila opažena kod dvorca Lužnica, ili kao autostoper sa željezničkom transportom, jer sjevernu granicu šume kod sela Zakot predstavlja željeznička pruga koja vodi od balkanske regije prema srednjoj Europi. U početku srpnja 2017. ustanovili smo namnoženje C. arcuata na lokaciji prvog nalaza i širjenje vrste na područje Krakovske hrastove šume, udaljeno 17 km zračne linije od sela Zakot.

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. © Éditions Quæ, 2015.

Ophiostomatoid 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. This 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. Bark 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. Thirteen 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. This 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.

U radu se iznose sažete spoznaje o herbivornoj entomofauni običnog koprivića (Celtis australis) u Sloveniji i Hrvatskoj, gdje je autohton, te u Madžarskoj gdje ga je unio čovjeka. Smisao provedenog istraživanja temeljen je na ideji intenzivnijeg uvođenja koprivića u reforestaciji i zamjeni pionirskih vrsta na kraškim područjima u kojima recentno dolazi do značajnih zdravstvenih problema, primjerice u kulturama crnog bora koje se suše pod utjecajem suše, kukaca i fitopatogenih gliva (npr. Diplodia pinea). Imajući u vidu moguće rizike ovog pristupa, kroz prikupljene i konzultirane literaturne izvore i vlastita nova opažanja revidiran je status koprivića kao drvenaste vrste u svjetlu njegove štetne entomofaune. Dobro su poznate opće spoznaje o rasprostranjenju i osnovnim ekološkim obilježjima običnog koprivića, pa u tom smislu znamo da je to bjelogorično drvo porijeklom iz Sredozemlja, Male Azije, Krima i područja od Kavkaza do Irana. Obični koprivić vrsta je otporna na sušu, vjetar i onečišćenje zraka u gradovima i može izdržati temperature do –15 ° C. Voli svjetlo, pješčana tla, suh i topao kraški teren. Prema svim svojim ekološkim zahtjevima spada u vrlo prikladnu vrstu drveća za pošumljavanje krša i suhih terena. Raščlamba prikupljene i dostupne literature o štetnicima na običnom kopriviću u Sloveniji, Hrvatskoj i Madžarskoj definirali smo početnu bazu već opisanih vrsta, koje smo zatim procjenjivali u svjetlu vlastitih terenskih istraživanja. Na lokalitetu Dekani, u blizini Kopra (Slovenija), u rujnu 2011. godine uzorkovali smo 15 grana C. australis s vidljivo oštećenim lišćem (mine) radi determinacije uzročnika. 2013. godine pregledali je šire područje submediteranske zone Slovenije i Hrvatske i analizirali simptome napada štetnih organizama na C. australis. Iduće sezone, 5. svibnja 2014, u mjestu Brseč, u blizini Opatije (Hrvatska) u urbanom okolišu zabilježili smo jaku defolijaciju (Slika 1). Ponovno smo uzeli uzorke 18 grana koprivića zajedno sa zatečenim gusjenicama različitih vrsta leptira. Slijedio je laboratorijski uzgoj i determinacija do razine vrste. Istraživanjem je sveukupno utvrđeno sedam vrsta leptira (Libythea celtis, Nymphalis polychloros, Archips xylosteana, Erannis defoliaria, Caloptilia fidella, Phyllonoricter millierella, Hyphantria cunea), jedna vrsta kornjaša (Neoclytus acuminatus) (Slika 6, 8, 11, 14, 17, 19) i jedna vrsta polukrilaca (Metcalfa pruinosa). Dvije vrste leptira (L. celtis i P. millierella) monofagne su na lišću C. australis, druge vrste utvrđenih istraživanjem imaju i druge vrste domaćina. Vrste N. polychloros, A. xylosteana, E. defoliaria, C. fidella i N. acuminatus po prvi puta su utvrđene kao štetnici C. australis i trebaju se dodati na već poznati popis štetnika običnog koprivića. Istraživanjem je također utvrđeno da su se monofagne vrste kukaca češće pojavljivale na kopriviću u posljednjem desetljeću. Prikupljeni rezultati predstavljaju bolji temelj strategiji zamjene problematičnih kultura crnog bora koje se suše pod utjecajem fitopatogenih gliva (npr. Diplodia pinea) s intenzivnijim pošumljavanjem običnim koprivićem. U posljednje vrijeme, a to je istraživanjem potvrđeno, javljaju se u povećanom intenzitetu neki već otprije poznati štetnici koprivića, ali i neke do sada nezabilježene štetne vrste. Povećana pojava defoliatora na C. australis, koji će, prema nekim projekcijama klimatskih kolebanja prosperirati u budućnosti zbog globalnog zatopljenja, mora se uzeti u obzir. Sadnja monokultura C. australis na suhim i toplim pozicijama vjerojatno će i dodatno povećati rizik od prenamnažanja nekih vrsta kukaca u tim sastojinama. Visoka koncentracija biljke hraniteljica nerijetko je glavni čimbenik njihovih gradacija, bilo da je riječ o monofagnim štetnicima koji neposredno ovise o količini dostupne hrane za koju su specijalizirani (L. celtis and P. millierella) ili generalistima (N. polychloros, A. xylosteana, E. defoliaria, C. fidella and N. acuminatus i dr.), koji se lako prilagođavaju trofičnom izobilju u obliku novounešenog domaćina.