Search

This research examines the rapid spread of the oak lace bug, Corythucha arcuata (Say, 1832), in Slovakia from 2020 to 2022. A native of the Nearctic region, this pest was first detected in Europe back in 2000 and has since extended across considerable part of the continent. Monitoring efforts revealed its presence in Slovakia in 2018, with subsequent surveys showing its distribution through the southern region and a northward expansion. The pest mainly infests oak trees, and in 2022, it was seen there on as many as 87% of the plots. Out of a total of 233 locations visited in the period 2020–2022, the bug was found on 169 sites, which represents 72.5%. The study identified the pedunculate and Turkey oak as primary host-plants. The results provided a clear trend from the bugs moving further north with each passing year, covering an estimated total distance of 84.5 km over the three-year timeframe. Factors influencing its spread included passive transport via vehicles and possible wind-assisted dispersal on a local scale. The study also highlights the need for continuous monitoring and management strategies to mitigate its impact on oak ecosystems.

Resistance of horse chestnut Aesculus hippocastanum ‘Mertelík’ to Cameraria ohridella was proven in the trial under semi-field conditions. Seedlings of vulnerable and resistant trees were grown together in rearing cages and were exposed to the strong attack from C. ohridella larvae. Significant differences in leaflet injuries were observed between susceptible and insect-resistant trees. Variety ‘Mertelík’ showed almost none or very small damages compared to high defoliation level in case of standard trees. The results confirmed that this resistant clone could be suitable for use under field conditions.

The gypsy moth is one of the most serious pests in forests and fruit tree plantations over prevailing parts of the Northern Hemisphere. This work is based on a literature review, and presents history of gypsy moth Lymantria dispar L., observed in Slovak forests within the period 1945–2020. The life cycle, hosts, natural enemies, population dynamics of pests, impact of outbreaks on forests and different management methods used in the past are discussed. Since 1945, there were nine gypsy moth outbreaks in Slovakia. Between 1945 and 2020, a total of 155,034 ha of deciduous forests were touched with varying intensity, representing an average annual damage of 2,040 ha. The strongest outbreak culminated in 2004. Totally 51,479 ha were attacked in the period of 2000–2008. We have found outbreak periods that repeat with frequency of 7.8 ±2.2 years and the average outbreak phase lasts 3.1 ±1.1 years. The period between two subsequent outbreaks seems to be more or less constant and duration of the outbreak phase seems to be gradually shortened during the study period. Several factors influencing the gypsy moth population dynamics in Slovakia are discussed. The role of biological control by using entomopathogenic fungus Entomophaga maimaiga is described.

Coniferous forests in Europe have a considerable number of pests that attack trees of all ages from youngest up to oldest ones. One of them is the large pine weevil Hylobius abietis. This species is widespread in Europe and occurs from warm southern areas (Spain) up to northern countries (Sweden, Finland). Larvae of this species do not cause damage, they help in the decomposition process of stumps and roots. Adults are harmful as they consume bark of young coniferous seedlings, above all of spruce and pine. One adult can consume on average 75 mm2 of bark per day. Individuals can live up to 4 years, and during their lives they can damage and kill several tens of coniferous seedlings. Traditional chemical protection of seedlings against this pest is and will gradually be more and more restricted or forbidden. In this review, we describe this method as well as all other alternative methods including biological protection. We estimate that H. abietis causes annual damages in Europe of almost 120 million € and damages several tens of thousands of hectares of young forest stands.

The entomopathogenic fungusEntomophaga maimaigawas 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 ofE. maimaigain gypsy moth cadavers was confirmed from both sites. [ABSTRACT FROM PUBLISHER]