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The Eurasian spruce bark beetle, Ips typographus (IT), is considered the most destructive insect pest of spruce forests in the Palaearctic region. Its control is based on a range of phytosanitary measures, insecticide treatments targeting the tree trunks, and pheromone trappings. Essential oils (EOs) from aromatic plants have been recognized as ecological alternatives to synthetic pesticides. In this study, EOs from plants in the Lamiaceae family (Origanum vulgare, Thymus vulgaris, Hyssopus officinalis and Mentha × piperita) and the Apiaceae family (Pimpinella anisum and Foeniculum vulgare) were studied for insecticidal and repellent effects against IT. EOs chemical composition was analyzed with gas chromatography mass spectrometry. IT adults were exposed to different concentrations of EOs, and their effects were recorded 2–96 h post-treatment. Significant differences in biological activity were observed, and the greatest insecticidal effect was detected for O. vulgare, T. vulgaris, and P. anisum; but O. vulgare EO was significantly more toxic at all doses or exposure times. Repellency index (RI) varied among the EOs and depended on dose and exposure time. At doses of 0.077‒0.219 µl/cm2, the RI increased until 4‒6 h post-treatment; after that period, it decreased. Pimpinella anisum, O. vulgare, and T. vulgaris EOs showed significantly higher repellent effects compared to F. vulgare and H. officinalis EOs. Mentha × piperita EOs exhibited neither repellent nor insecticidal activity against IT. To our knowledge, this is the first time that EOs biological activity against IT was studied.

Two local strains of Beauveria bassiana originally isolated from naturally infected spruce bark beetles in Slovakia were tested for their virulence to Ips typographus (IT) and for their compatibility with a polymeric matrix composed of low-molecular polyethylene. Conidia could be homogenously immobilized in the low-molecular polyethylene matrix with no adverse effect on their viability and infectivity. At constant temperature (25°C), viability of immobilized conidial decreased only by 1–2% after 7 or 14 days when compared with non-formulated conidia. In field conditions, viability of conidia formulated in the matrix was even significantly higher than non-formulated conidia 35 days after their application in traps. Conidia incorporated into the polymeric matrix were infective to IT adults in laboratory bioassays. Mean values of LC50 for native conidia (0.72–2.05 × 106 conidia ml−1) and conidia immobilized in the polymeric matrix (0.64–1.03 × 105 conidia mm−2) demonstrated high virulence. The effica...

Cameraria ohridella is a major pest of horse-chestnut trees in Europe causing permanent outbreaks and severe defoliations. Entomopathogenic Beauveria species are common mortality factors of C. ohridella pupae overwintering in leaf litters. In this study, laboratory bioassays were conducted to determine the ability of local Beauveria strains to colonize horse-chestnut leaves endophytically and test their antagonistic activity against C. ohridella in colonized leaves. Two strains of Beauveria bassiana (AM_EF0111 isolated from horse-chestnut leaf tissue and AM_EP0715 isolated from a C. ohridella pupa) and one strain of B. pseudobassiana (AM_SO1015 obtained from soil) were used for in planta bioassays. The selected strains demonstrated high virulence to leaf miner pupae after a topical treatment with spore suspensions. LC50 ranged between 2.49 and 3.19 × 106 conidia ml−1. Horse-chestnut saplings were inoculated with the fungi through their direct immersion into spore suspensions (107 conidia ml−1). Endophytic colonization was successful and a mean colonization rate reached 57.44–66.08% 15 days post-inoculation. It decreased over time for all strains, but the fungi were still present in leaf tissue 54 days post-inoculation. AM_EF0111 strain was significantly more effective in colonizing saplings than AM_SO1015 and AM_EP0715. Fungus-colonized and untreated (control) saplings were infested with the leaf miner 31 days after inoculation and development of larval mines was monitored. In Beauveria-colonized saplings, damage by leaf miner was significantly lower compared to control plants. On day 23 post-infestation, the damaged leaf area of colonized leaves was 5-times smaller compared to control saplings. The negative effect on larval tunneling was significantly greater for strain AM_EP0715 than for the other two strains. Survival of leaf miners was considerably affected in colonized leaves, but mycosis was detected only in 5.41–9.23% of cadavers. No mycosed individuals were collected from control saplings. Pupae from colonized leaves were smaller in dimensions with lower weight than pupae form control plants. The same Beauveria strains recovered from leaves at the end of colonization bioassays showed no significant decrease in LC50 values.

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.

The cypress aphid (Cinara cupressi) is listed among the hundred most important invasive pests in the world. In Chile, it was first detected in 2003 and currently is present throughout the country. In the course of a survey of their natural enemies in Chile, three strains of entomopathogenic fungi were isolated. The isolates were identified and tested against the aphid in laboratory experiments. Two further entomopathogenic fungi (ARSEF 5126 and 5128), formulated in the mycoinsecticides Vertalec® and Mycotal®, were used as reference strains. The three Chilean isolates were identified genomically as Lecanicillium attenuatum and were pathogenic to third-instar nymphs. The isolate ARSEF 13279 yielded the lowest overall lethal concentration (LC50), 3 × 105 conidia ml−1 at four days post-inoculation, and the shortest lethal time (LT50), 3.7 days after inoculation with 106 conidia ml−1. The results indicate that the isolates have considerable potential as microbial control agents of the invasive cypress aphid.

The large pine weevil (Hylobius abietis) is an important pest of freshly planted coniferous trees. Feeding damage to conifer seedlings can be prevented by protecting the seedlings (mechanically or chemically), or by reducing H. abietis abundance. The entomopathogenic fungus Beauveria bassiana has promise for H. abietis control. To test the effects of the B. bassiana-colonized carriers (25 mm in diameter and colonized by strain AMEP20) on H. abietis adults that move into forest clearances, we performed several experiments. These included an experiment in Petri dishes under laboratory conditions, an experiment in cages with Norway spruce seedlings under semi-natural conditions, and a field experiment. Infection by B. bassiana and mortality of H. abietis was confirmed in all three experiments. The total mortality rate in all Petri dishes with B. bassiana carriers after 14 days was 74% (80% with fresh carriers; 68% with carriers that had been treated with UV light; 82% for carriers that had been frozen; 45% for adults that were exposed to carriers for only 24 h; and 95% for carriers that had been stored at 4 °C for 2 months). The mortality of H. abietis adults was affected by the absence/presence of carriers in the cages with spruce plants. The number of dead adults after 4 weeks of treatment in forest clearing were higher in plots with carriers than in the control plot. Mortality was highest for adults trapped in the plot with carriers on trap barks (58%), followed by the plot with carriers and an attractant (48%), and followed by the plots with carriers without an attractant (35%). The results suggest that carriers colonized by the entomopathogenic fungus B. bassiana could be suitable for reducing H. abietis abundance in forests. The results indicated that H. abietis adults may be infected by B. bassiana after only a short exposure to carriers. The B. bassiana-colonized carrier is ready-to-use, i.e., it could be immediately produced and applied.

Kollar J., Barta M . (2016): The first record of tulip tree aphid, Illinoia liriodendri (Hemiptera: Aphididae ), from Slovakia – short communication. Plant Protect. Sci., 52: 142–146. The tulip tree aphid, Illinoia liriodendri , is reported in Slovakia for the first time. Colonies of I. liriodendri were found on tulip trees, Liriodendron tulipifera , in two locations of south-western Slovakia in 2014 and 2015. Colonies of nymphs and viviparous females fed on the underside of leaves with no significant symptoms of damage to tulip trees. In this short study, the first report of the aphid from Slovakia is presented and original illustrations with results of morphometric analysis of alate viviparous females are provided.

This is the first report on the occurrence of andromeda lace bug, Stephanitis (Stephanitis) takeyai Drake and Maa, 1955, and rhododendron lace bug, Stephanitis (Stephanitis) rhododendri Horvath, 1905, in Slovakia. Syntopic colonies of both species were found on rhododendron shrubs (Rhododendron sp.) in south-western Slovakia in 2015. The feeding of the lace bugs resulted in damage to infested rhododendrons. Leaves turned yellow and brown, prematurely dropped what led to continuous drying up of twigs and the whole plants. Details on morphology of adult stages of the two species, description of damage symptoms and economic importance of these pests are presented and discussed.

Gypsy moth, Lymantria dispar L., is one of the most important pests of deciduous trees in Europe. In regular cycles, it causes large-scale defoliation mostly of oak, Quercus spp., forests. Government authorities in the most infested countries in Europe conduct large-scale applications of pesticides against gypsy moth. In 1999, a new natural enemy, the entomopathogenic fungus Entomophaga maimaiga, was successfully introduced into a gypsy moth population in Bulgaria. Recent investigations suggest that now E. maimaiga is quickly spreading in Europe. Herein, past studies are reviewed regarding this fungus with special emphasis on its potential for becoming an important factor regulating gypsy moth populations in Europe, focusing on the host's population dynamics in relation to the fungus, the influence of environmental conditions on fungal activity, the influence of E. maimaiga on the native entomofauna, including other gypsy moth natural enemies, and spread of the fungus. Based on this analysis, the potential of E. maimaiga for providing control in European gypsy moth populations is estimated.

Leptoglossus occidentalis, a species native to North America, has been expanding through European conifer forests. The fast spread across the European continent demonstrates its great invasive potential and poses a threat to conifer seed orchards. To better understand its potential distribution and population growth in infested regions, the temperature-dependent development in laboratory as well as life history, phenology, and winter survival were investigated in southern Slovakia during 2009–2011. The lower temperature thresholds to complete embryonic and postembryonic development estimated with the linear model were 13.38 and 14.37 °C, respectively. The number of degree-days required for completion of development from egg to adult estimated by the linear model was 533 °C. Overwintered adults or late nymphal instars became active in mid-March, oviposition was not observed before mid-April, and nymphs passing through five stages reached adulthood after mid-July. Individual females laid on average 31 eggs (max 78). The second generation started in August but did not complete its development till winter, although part of the 5th instar nymphs did survive until spring. Using temperature data of 41 localities across Europe and cumulative degree-days for complete life cycle, a prediction of the potential number of generations per year was made. In conditions of southern Slovakia L. occidentalis was univoltine, but up to four generations per year were estimated depending on the locality in Europe.

The entomopathogenic fungus Entomophaga maimaiga was found for the first time in Slovakia in 2013. Late instar larvae of gypsy moth, Lymantria dispar, from two sites with different population densities were dissected to evaluate the presence of pathogens. The presence of conidia and resting spores of E. maimaiga in gypsy moth cadavers was confirmed from both sites.

Seasonal development of entomophthoralean infection in colonies of Diuraphis noxia and Rhopalosiphum maidis was evaluated on summer barley under conditions of south-western Slovakia in 2001 and 2002. D. noxia was infesting summer barley during both years, while R. maidis was only recorded in 2002. Further three cereal aphids, Rhopalosiphum padi, Metopolophium dirhodum and Sitobion avenae, were also observed on summer barley. Complex of entomophthoralean fungi identified in cereal aphid colonies included four species, Pandora neoaphidis, Entomophthora planchoniana, Conidiobolus obscurus and Neozygites fresenii, with P. neoaphidis as the most prevalent fungus during both years. Two parasitic fungi, P. neoaphidis and E. planchoniana, were identified from D. noxia, but P. neoaphidis was predominant. Infection rate in D. noxia colonies was low, not exceeding 15% and 10% in 2001 and 2002, respectively. Only nine R. maidis individuals were killed with entomophthoralean fungi. The fungi were identified as P. neoaphidis and C. obscurus. No epizootics were observed in the aphid colonies. The fungi could not control development of the aphid populations since they did not appear until high host densities had been established in the crops.

The seasonal dynamics of the pea aphid, Acyrthosiphon pisum Harris, and entomopathogenic fungi from the order Entomophthorales attacking the aphid were analysed in alfalfa and field pea crops during the growing seasons of 1998 and 1999 at Nitra-Malanta. In both years, pea aphid populations on pea showed a pattern with one peak, culminated at flowering and pod formation. The infestation level on alfalfa was low in both years. Entomopathogenic fungi attacking the pea aphid were identified as Erynia neoaphidis Remaudičre and Hennebert and Conidiobolus obscurus (Hall and Dunn) Remaudičre and Keller. Both pathogens infected the aphid on pea, but only E. neoaphidis was found in the alfalfa plots. Infected aphids were not found on alfalfa during 1999. The maximum levels of infected aphids on pea were 10.30% and 48.39% in 1998 and 1999, respectively. During both years alate aphids were more frequently attacked than apteral ones. Correlation coefficients indicated a positive relationship between the number of infected aphids and precipitation, but this relationship was weak or moderately strong. A strong correlation was found between the number of dead aphids and number of alate aphids counted 5 to 10 days earlier.

The species spectrum of entomophthoralean fungi parasiting aphids was investigated in Slovakia. The surveys focused on aphid fauna occupying both agricultural crops and vegetation at non-crop sites. During the surveys, 15 different entomophthoralean species were identified from 66 aphid species. Of these 15 fungal species, eight had not previously been recorded in Slovakia and one species, Erynia erinacea (Ben-Ze’ev et Kenneth) Remaudiere et Hennebert, had not been recorded previously in Central Europe. New hosts for some parasitic fungi were also recorded. The occurrence of fungal infection and the fungal species spectrum varied with sampling period and sampling area. In general, the fungi were observed parasiting aphid populations from April until November. Pandora neoaphidis (Remaudiere et Hennebert) Humber was the predominant fungal pathogen and could effectively reduce aphid populations. Entomophthora planchoniana Cornu and Conidiobolus obscurus (Hall et Dunn) Remaudiere et Keller were also common pathogens of aphids, but without an epizootic potential. On the other hand, Neozygites fresenii (Nowakowski) Remaudiere et Keller had a strong tendency to establish epizootics in dense aphid colonies, especially in those of the black bean aphid. Other entomophthoralean species observed in the country were considered to be minor aphid pathogens on account of their low occurrence, lower specificity to aphids, or high specificity to a single aphid species. This is the first detailed report to date on the occurrence of Entomophthorales in Slovakia.