61 research outputs found
Widespread Distribution of the Sycamore Seed Bug Belonochilus numenius (Hemiptera: Heteroptera: Lygaeidae) Throughout the Republic of North Macedonia
Background and Purpose: The sycamore seed bug, Belonochilus numenius (Say, 1831), was recorded for the first time in Europe in 2008, with finds in that same year in two separate locations in Spain and two in France. Since then, it has been reported to be present in 17 European countries. Once it reached Europe, the fast spread and establishment of this species was facilitated both by the increased plant trade and the relative frequency of plane trees (Platanus x acerifolia, P. orientalis and P. occidentalis) planted on a wide scale across the continent due to their popularity as urban and peri-urban trees.
Materials and Methods: In the summer of 2019 we inspected urban, peri-urban and natural populations and groups of plane trees throughout North Macedonia, on a total of 44 sites, looking for presence of nymphs and adults of this insect on seed balls. We collected specimens and related data and made identification based on specific external characteristics typical of B. numenius.
Results: We report the first record of B. numenius in the Republic of North Macedonia from July 2019, from P. x acerifolia in Skopje. Furthermore, after inspecting plane trees throughout the country we report the presence of this insect in 29 cities and towns, 3 peri-urban and in 1 natural population of P. orientalis.
Conclusions: From the widespread distribution of this insect species, we conclude that it has entered the territory of North Macedonia many years prior, very likely soon after first records in Serbia in 2011 and Bulgaria in 2012, but has since been overlooked
Phytophthora cactorum (Lebert & Cohn) J. Schröt as causal agent of dieback of chestnut and apple trees in Macedonia
Acknowledgments. SCOPES Joint Research Project "Invasive chestnut diseases in the Balkans and Georgia - epidemiological research and management options". Multilateral project (Switzerland, Croatia, Macedonia and Georgia), 2013-2016 (IZ73Z0_152525). SEE-ERA.NET PLUS Joint Research Project "Diversity and invading Phytophthora spp. plant pathogens in agro and forest ecosystems in Southeast Europe". Multilateral project (Bulgaria, Macedonia, Greece, Serbia and Romania), 2010-2012. COST (Cost Action FP0801: Established and Emerging Phytophthora: Increasing Threats to Woodland and Forest Ecosystems.)Peer reviewedPublisher PD
The Molecular Line Opacity of MgH in Cool Stellar Atmospheres
A new, complete, theoretical rotational and vibrational line list for the A-X
electronic transition in MgH is presented. The list includes transition
energies and oscillator strengths for all possible allowed transitions and was
computed using the best available theoretical potential energies and dipole
transition moment function with the former adjusted to account for experimental
data. The A-X line list, as well as new line lists for the B'-X and the X-X
(pure rovibrational) transitions, were included in comprehensive stellar
atmosphere models for M, L, and T dwarfs and solar-type stars. The resulting
spectra, when compared to models lacking MgH, show that MgH provides
significant opacity in the visible between 4400 and 5600 Angstrom. Further,
comparison of the spectra obtained with the current line list to spectra
obtained using the line list constructed by Kurucz (1993) show that the Kurucz
list significantly overestimates the opacity due to MgH particularly for the
bands near 5150 and 4800 Angstrom with the discrepancy increasing with
decreasing effective temperature.Comment: 10 pages, 4 figures, 3 table
Coppice Forest Management Planning and the Regeneration Potential of Pure and Mixed Oak Coppice Forests in North Macedonia
Background and Purpose: Coppicing is the most widely used silvicultural system in North Macedonia and coppice forests together with shrubs cover cca. 69% of the forest cover area. Pure and mixed stands of oak coppice forests alone cover about 50% of the total forest area subject to current Forest Management Plans. In general, coppices are routinely managed, especially when coppicing as a system is planned to be continued. However, sustainability can be threatened if attention is not paid regarding the age of trees/stands and the presence of undesired tree species. The purpose of this study was to determine: (1) quantitative and qualitative aspects of planned management activities in oak coppices throughout the country, (2) the resprouting potential of over-mature oak coppices, and (3) their potential for generative regeneration.
Materials and Methods: We analyzed all official forest management plans in the country, in order to assess planned activities and the methods of management. Additionally, 21 experimental plots were set in order to determine the resprouting potential of over-mature (85 to 95 years) coppices of Quercus petraea and Q. frainneto which previously have been subject of clear-cutting. We took a total count of sprouts on all experimental plots, while generative regeneration seedlings were counted on 4 schematically positioned subplots in each experimental plot. Sprouts and generative seedlings were categorized by height.
Results and Conclusions: According to the data from forest management plans, coppicing is planned to remain as a management system on 401,636 ha, of the total of 450,975 ha of oak coppice forests. Indirect conversion to high forests is planned on 39,137 ha, while direct conversion with substitution is planned for 10,202 ha. In field trials, resprouting was registered on only 38% of the stools. Generative regeneration was recorded in both oak species in numbers which indicate good potential for conversion of oak coppice stands into high forests by seed felling. However, numerous sprouts of other species (Corylus avellana, Fraxinus ornus, Acer heldreichii), which reach up to 3 meters in height within two seasons, are potentially dangerous for dominating oak seedlings
The rovibrational spectrum of BeH, MgH and CaH at high temperatures in the state: a theoretical study
Accurate line lists for three molecules, BeH, MgH and CaH, in their ground
electronic states are presented. These line lists are suitable for temperatures
relevant to exoplanetary atmospheres and cool stars (up to 2000K). A
combination of empirical and \textit{ab initio} methods is used. The
rovibrational energy levels of BeH, MgH and CaH are computed using the programs
Level and DPotFit in conjunction with `spectroscopic' potential energy curves
(PECs). The PEC of BeH is taken from the literature, while the PECs of CaH and
MgH are generated by fitting to the experimental transition energy levels. Both
spin-rotation interactions (except for BeH, for which it is negligible) and
non-adiabatic corrections are explicitly taken into account. Accurate line
intensities are generated using newly computed \textit{ab initio} dipole moment
curves for each molecule using high levels of theory. Full line lists of
rotation-vibration transitions for BeH, MgH, MgH, MgH
and CaH are made available in an electronic form as supplementary data
to this article and at \url{www.exomol.com}.Comment: MNRAS (in press
A worldwide perspective on the management and control of Dothistroma needle blight
Dothistroma needle blight (DNB) caused by Dothistroma septosporum and Dothistroma
pini is a damaging disease of pine in many countries. The disease led to the abandonment
of planting susceptible Pinus species in parts of Africa, Asia, Australasia, Europe
and North America. Although the disease can be effectively controlled using copper
fungicides, this chemical is only routinely applied in forests in New Zealand and
Australia. Other management tactics aimed at making conditions less favourable for
disease development, such as thinning or pruning, may be effective on some, but not
all, sites. Disease avoidance, by planting non-susceptible species, is the most common
form of management in Europe, along with deployment of hosts with strong disease
resistance. Although D. septosporum is present almost everywhere Pinus is grown, it is
important that an effort is maintained to exclude introductions of new haplotypes that
could increase virulence or enable host resistance to be overcome. A global strategy to
exclude new introductions of Dothistroma and other damaging forest pathogens, facilitated
by collaborative programmes and legislation, is needed.This study was partially supported by the EU COST Action FP1102
DIAROD (Determining Invasiveness and Risk of Dothistroma, http://
www.cost.eu/COST_Actions/fps/FP1102)http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1439-03292017-10-31hb2017Forestry and Agricultural Biotechnology Institute (FABI)GeneticsPlant Scienc
Semantic Network Processing System Used for Simulation, Fast Prototyping and Configuration of Large Software Systems
Horizontal transmission of hypoviruses between vegetative compatibility types of Cryphonectria parasitica in Macedonia
Biological control of chestnut blight with
hypovirulence depends on the successful transmission of hypoviruses between individuals of the chestnut blight fungus, Cryphonectria parasitica. Vegetative incompatibility inhibits horizontal virus transmission, but not completely. In an effort to assess the potential for the spread of hypoviruses in the Republic of Macedonia, we studied the transmission of Cryphonectria hypovirus 1 (CHV-1) among the five observed vegetative compatibility (vc) types of C. parasitica. One fungal isolate of each vc type was infected with CHV-1 and was paired in vitro with isolates of all other vc types for a total of 20 combinations of virus donors and recipients, and 250 replicate trials per combination. Virus transmission was scored after 7 days as successful if the recipient isolate took on an unpigmented culture phenotype typical of virus infection. Transmission occurred at high frequencies between some pairs of vc types, but in <1% of the
trials for 10 of the 20 combinations of donors and
recipients. Asymmetric transmission was observed
between some vc types that had different alleles at
vegetative incompatibility loci vic1 or vic7; i.e.,
transmission occurred at high frequencies in one
direction, but very low frequencies between the same pair of isolates in the opposite direction. The expected virus transmission, calculated as the average transmission predicted for any two randomly chosen individuals from a population, was highly negatively correlated to vc type diversity. Results for isolates of C. parasitica from Macedonia were similar to those from Italy, but less transmission was generally observed. Differences in genetic background effects
on transmission may vary among different populations even when isolates differ by the same vic alleles
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