BIOLOGICKÉ VLASTNOSTI SLOVENSKÝCH IZOLÁTOV ENTOMOPATOGÉNNEJ HUBY PANDORA NEOAPHIDIS (REMAUDIÈRE ET HENNEBERT) HUMBER (ZYGOMYCETES, ENTOMOPHTHORALES)

Intraspecific variability of biological characteristics within entomopathogenic fungus Pandora neoaphidis was evaluated. Fifteen isolates of the fungus were obtained from 5 aphid species in Slovakia. Size of conidia, conidial germination, virulence, radial growth, and biomass production were evaluated. Conidial size varied considerably with exception of isolates originating from the same host population. Conidial germination was observed on all the surfaces tested and it was greatest at saturated humidity. Virulence, daily rate of radial growth and biomass production varied depending on isolates. Isolates obtained from the same host colonies during fungal epizootics shoved also significant differences in the characteristics, what may suggest that epizootics in aphid populations are caused by associations of strains and not by prevalence of a single virulent strain.V práci sa hodnotila vnútrodruhová variabilita biologických vlastností entomopatogénnej huby Pandora neoaphidis. Hodnotilo sa 15 izolátov získaných z 5 druhov vošiek. Posudzovali sa nasledovné vlastnosti: veľkosť a klíčivosť konídií, virulencia, radiálny rast a produkcia biomasy izolátov. Zistili sa preukazné rozdiely vo veľkosti konídií, s výnimkou izolátov získaných z vošiek pochádzajúcich z rovnakých populácií. Konídie klíčili na všetkých hodnotených povrchoch, najvyššia klíčivosť bola pri 100% relatívnej vlhkosti. Virulencia izolátov, denná rýchlosť rastu a produkcia biomasy varírovala v závislosti od izolátu. Izoláty, ktoré boli získané z rovnakých kolónií vošiek počas epizoócií patogéna preukázali tiež významné rozdiely v hodnotených vlastnostiach. Toto poukazuje na skutočnosť, že epizoócie v populáciách vošiek sú vyvolávané asociáciou viacerých a nie prevalenciou jedného virulentného kmeňa patogéna

BIOLOGICAL CHARACTERISTICS OF SLOVAK ISOLATES OF ENTOMOPATHOGENIC FUNGUS PANDORA NEOAPHIDIS (REMAUDIÈRE ET HENNEBERT) HUMBER (ZYGOMYCETES, ENTOMOPHTHORALES)

Intraspecific variability of biological characteristics within entomopathogenic fungus Pandora neoaphidis was evaluated. Fifteen isolates of the fungus were obtained from 5 aphid species in Slovakia. Size of conidia, conidial germination, virulence, radial growth, and biomass production were evaluated. Conidial size varied considerably with exception of isolates originating from the same host population. Conidial germination was observed on all the surfaces tested and it was greatest at saturated humidity. Virulence, daily rate of radial growth and biomass production varied depending on isolates. Isolates obtained from the same host colonies during fungal epizootics shoved also significant differences in the characteristics, what may suggest that epizootics in aphid populations are caused by associations of strains and not by prevalence of a single virulent strain

New facts about distributioN aNd host spectrum of the iNvasive Nearctic coNifer pest, LeptogLossus occidentaLis (heteroptera: coreidae) iN south-westerN slovakia

abstract: In the summer 2007, the alien coreid bug Leptoglossus occidentalis Heidemann, 1910 was observed in the Arboretum Mlyňany SAS. This important seed feeder of coniferous trees native to North America was detected on immature cones of Pinus x schwerinii. During the summer 2008, an occurrence of the western conifer seed bug was studied in collections of conifers in the arboretum as well as in parks and public greenery of several settlements in south-western Slovakia. The seed bug was recorded on 11 pine species (Pinus x schwerinii, P. strobus, P. ponderosa, P. sylvestris, P. nigra, P. mugo, P. flexilis, P. griffithii, P. armandii, P. densiflora and P. rigida), 5 spruce species (Picea abies, P. orientalis, P. engelmanii, P. wilsonii, and P. asperata), on California incense-cedar (Calocedrus decurrens) and on Douglas-fir (Pseudotsuga menziesii). An appearance of natural enemies was studied on collected seed bugs and one individual was found to be infected with entomopathogenic fungus Paecilomyces fumosoroseus. This is the first record of natural infection of L. occidentalis by this fungus

Spruce bark beetles as a biological waste that can be processed in a biogas plant

Biogas plays an important role in reducing the amount of biowaste that is converted to methane which is usable by multiple pathways in the energy sector. Bark beetles are among the most important pests of spruce forests in Europe. Principal measures of managing bark beetle populations include trapping them with pheromone traps. Biomass of bark beetles collected by the traps constitutes a waste of forest resources that could potentially be processed in biogas plants. The aim of this study was to provide information about the trapping of bark beetles by pheromone traps in Tatra National Park during 2005-2018 and to verify the energy potential of a combination of liquid digestate and bark beetle biomass collected by pheromone traps. The bark beetle biomass is a seasonal small-volume nitrogen-rich material which could be processed at agricultural biogas plants. The biochemical methane potential batch test performed at 40 degrees C showed a high degree of digestion of milled beetles within 40 days, with a methane production of 0.242 Nm(3) per kilogram of total solids (TS). The single-stage low-solids mesophilic fed-batch anaerobic digestion of untreated beetles was carried out in a lab-scale rotary drum reactor. Within 52 days, the average organic loading rate was 1.019 kg VS m(-3)day(-)(1), where VS stands for volatile solids. The specific biogas and methane production reached 0.218 Nm(3)kg(-1) TS and 0.140 Nm(3)kg(-1) TS, respectively. The cuticles of the beetle bodies were not obviously disturbed by the fermentation process. The digestate was quite rich in nitrogen, but the other element contents did not differ too much from fertilizer made from manure or phytomass.Web of Science44217916

Využitie MALDI-TOF hmotnostnej spektrometrie na rýchlu identifikáciu druhov Beauveria bassiana a Beauveria pseudobassiana

Species of the genus Beauveria are entomopathogenic fungi used in biological control to protect against insect pests. Identification of species is based on observation of morphological, phylogenetic and genetic differences. Currently, MALDI-TOF (Matrix Assisted Laser Desorption/Ionization-Time of Flight) mass spectrometry is often used in microbial diagnostic but identification of Beauveria species has not been tested before. The aim of this work was the possibilities of this method and to compare it with genetic analysis. Twenty strains of B. bassiana and B. pseudobassiana isolated from insect cadavers, mycoinsecticides and soil samples were used. Sequences of ITS (Internal Transcribed Spacer) region were used for genetic identification of strains. Sequences and results from protein analysis of isolates were compared with the reference strains of B. bassiana and B. pseudobassiana. Results of MALDI Biotyper softvare identification were correct for all strains. Identification was reliable with high log score (>2.1) for most of strains. Score value less than 1 was observed only in a single case - strain GHA isolated from mycoinsecticide Botanigard.The result of both analyses was also dendrogram (phylogenetic tree) which showed high degree of result consistence. MALDI-TOF identification of fungi from Beauveria genus is usable for fast and reliable identification of entomopathogenic fungi isolates acquired from environment and results can be utilized in conservation biocontrol strategies in agriculture and forest ecosystems.Rod Beauveria patrí medzi entomopatogénne huby využívané v biologickej regulácii hmyzích škodcov v poľnohospodárstve. Identifikácia druhov je založená na pozorovaní morfologických, fylogenetických a genetických rozdielov. V súčasnosti sa do popredia dostáva aj MALDI-TOF (Matrix Assisted Laser Desorption/Ionization-Time of Flight) hmotnostná spektrometria, ktorá v prípade rodu Beauveria nebola doposiaľ testovaná. Cieľom našej práce bolo zhodnotiť možnosť využívan ia tejto metódy na základe porovnania s genetickou analýzou. Použitých bolo 20 kmeňov B. bassiana a B. pseudobassiana, získaných izoláciou z kadáverov hmyzu, komerčne dostupných prípravkov a pôdnych vzoriek. Na genetickú identifikáciu kmeňov bol použitý región ITS (Internal Transcribed Spacer). Výsledné sekvencie a analýzy proteínových spektier vzoriek boli porovnávané s referenčnými kmeňmi B. bassiana a B.pseudobassiana. Výsledky identifikácie s využitím softvéru MALDI Biotyper boli správne pre všetky analyzované kmene. Identifikácia bola spoľahlivá s vysokým log skóre (>2.1) pre väčšinu kmeňov. Len v jedinom prípade – kmeň GHA, izolovaný z mykoinsekticídu Botanigard, bolo skóre nižšie ako 1. Výsledkom oboch analýz bol dendrogram (fylogenetický strom), ktorý poukázal na zhodnú klasifikáciu s referenčnými kmeňmi. MALDI-TOF identifikáciu húb z rodu Beauveria je možné využiť na rýchlu a spoľahlivú diagnostiku izolátov entomopatogénnych húb získaných z prostredia a výsledky využiť v systémoch biologickej ochrany lesných a poľnohospodárskych ekosystémov

Worldwide diversity of endophytic fungi and insects associated with dormant tree twigs

International trade in plants and climate change are two of the main factors causing damaging tree pests (i.e. fungi and insects) to spread into new areas. To mitigate these risks, a large-scale assessment of tree-associated fungi and insects is needed. We present records of endophytic fungi and insects in twigs of 17 angiosperm and gymnosperm genera, from 51 locations in 32 countries worldwide. Endophytic fungi were characterized by high-throughput sequencing of 352 samples from 145 tree species in 28 countries. Insects were reared from 227 samples of 109 tree species in 18 countries and sorted into taxonomic orders and feeding guilds. Herbivorous insects were grouped into morphospecies and were identified using molecular and morphological approaches. This dataset reveals the diversity of tree-associated taxa, as it contains 12,721 fungal Amplicon Sequence Variants and 208 herbivorous insect morphospecies, sampled across broad geographic and climatic gradients and for many tree species. This dataset will facilitate applied and fundamental studies on the distribution of fungal endophytes and insects in trees

Climate, host and geography shape insect and fungal communities of trees.

Non-native pests, climate change, and their interactions are likely to alter relationships between trees and tree-associated organisms with consequences for forest health. To understand and predict such changes, factors structuring tree-associated communities need to be determined. Here, we analysed the data consisting of records of insects and fungi collected from dormant twigs from 155 tree species at 51 botanical gardens or arboreta in 32 countries. Generalized dissimilarity models revealed similar relative importance of studied climatic, host-related and geographic factors on differences in tree-associated communities. Mean annual temperature, phylogenetic distance between hosts and geographic distance between locations were the major drivers of dissimilarities. The increasing importance of high temperatures on differences in studied communities indicate that climate change could affect tree-associated organisms directly and indirectly through host range shifts. Insect and fungal communities were more similar between closely related vs. distant hosts suggesting that host range shifts may facilitate the emergence of new pests. Moreover, dissimilarities among tree-associated communities increased with geographic distance indicating that human-mediated transport may serve as a pathway of the introductions of new pests. The results of this study highlight the need to limit the establishment of tree pests and increase the resilience of forest ecosystems to changes in climate

Hypocrealean Fungi Associated with Hylobius abietis in Slovakia, Their Virulence against Weevil Adults and Effect on Feeding Damage in Laboratory

In temperate regions of Europe, the large pine weevil, Hylobius abietis, is a major pest of coniferous forests mostly at sites where clear-felling is followed by planting of saplings. Control measures against this pest are based on silvicultural techniques, an application of physical barriers on stems of saplings and insecticide treatments. To avoid the use of insecticides, alternative measures such as biological control have been investigated. The goal of the present study was to obtain local strains of entomopathogenic fungi (Ascomycota, Hypocreales) from natural populations of H. abietis, and to investigate their efficacy against the weevil. A survey on entomopathogenic fungi was undertaken at clear-felled areas of spruce forests in northern Slovakia. Two Beauveria species, B. bassiana and B. pseudobassiana, were identified, and 22 in vitro strains were obtained. Mean prevalence of infected adults was low (2.10% ± 0.67%) and the mycosis was mostly recorded during May and June. Virulence of Beauveria strains against the weevil was tested in laboratory. B. bassiana strain AMEP20 was significantly most virulent (LC50 of 0.65 ± 0.10 × 108 conidia mL−1). Treatment with conidia of AMEP20 strain affected feeding damage by the weevil on bark of Scots pine twigs. Daily bark consumption by B. bassiana-treated weevils was lower than by untreated individuals and decreased with increasing conidia concentration used for the treatment. In the outdoor experiment, AMEP20 strain killed weevils that fed on spruce saplings treated with conidia suspensions. Mortality due to mycosis on weevils exposed to the conidia-treated saplings reached 30.0%–76.5% and 55.0%–88.2% after 32 and 46 days, respectively

BIOLOGICKÉ VLASTNOSTI SLOVENSKÝCH IZOLÁTOV ENTOMOPATOGÉNNEJ HUBY PANDORA NEOAPHIDIS (REMAUDIÈRE ET HENNEBERT) HUMBER (ZYGOMYCETES, ENTOMOPHTHORALES)

Intraspecific variability of biological characteristics within entomopathogenic fungus Pandora neoaphidis was evaluated. Fifteen isolates of the fungus were obtained from 5 aphid species in Slovakia. Size of conidia, conidial germination, virulence, radial growth, and biomass production were evaluated. Conidial size varied considerably with exception of isolates originating from the same host population. Conidial germination was observed on all the surfaces tested and it was greatest at saturated humidity. Virulence, daily rate of radial growth and biomass production varied depending on isolates. Isolates obtained from the same host colonies during fungal epizootics shoved also significant differences in the characteristics, what may suggest that epizootics in aphid populations are caused by associations of strains and not by prevalence of a single virulent strain.V práci sa hodnotila vnútrodruhová variabilita biologických vlastností entomopatogénnej huby Pandora neoaphidis. Hodnotilo sa 15 izolátov získaných z 5 druhov vošiek. Posudzovali sa nasledovné vlastnosti: veľkosť a klíčivosť konídií, virulencia, radiálny rast a produkcia biomasy izolátov. Zistili sa preukazné rozdiely vo veľkosti konídií, s výnimkou izolátov získaných z vošiek pochádzajúcich z rovnakých populácií. Konídie klíčili na všetkých hodnotených povrchoch, najvyššia klíčivosť bola pri 100% relatívnej vlhkosti. Virulencia izolátov, denná rýchlosť rastu a produkcia biomasy varírovala v závislosti od izolátu. Izoláty, ktoré boli získané z rovnakých kolónií vošiek počas epizoócií patogéna preukázali tiež významné rozdiely v hodnotených vlastnostiach. Toto poukazuje na skutočnosť, že epizoócie v populáciách vošiek sú vyvolávané asociáciou viacerých a nie prevalenciou jedného virulentného kmeňa patogéna