North-Westward Expansion of the Invasive Range of Emerald Ash Borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) towards the EU: From Moscow to Saint Petersburg

Agrilus planipennis is a devastating invasive pest of ash trees in European Russia, Ukraine, and North America. To monitor the north-western limit of its European invasive range, in June 2018 we established 10 study plots along the federal highway M10 (Russia) that runs between Moscow and Saint Petersburg through Tver' City (approx. 180 km from Moscow), and lined with ash trees. On each plot, 2-4 Fraxinus pennsylvanica trees with heights ranging 6.1-17.0 m and diameters ranging 7.0-18.0 cm were girdled, i.e., 50 cm of their bark were removed. The study plots were visited and girdled trees were examined in September and November, 2018, and in October, 2019. Observations revealed that the current continuous north-western limit of A. planipennis range in European Russia coincides with the north-western border of Tver' City and this range limit has not distinctly shifted north-westward during 2015-2019. In spite of the rich food supply (due to abundant F. pennsylvanica and F. excelsior plantings) in Tver' City and along roads going to and from, the population density of A. planipennis in the area is currently low. Recent (September 2020) sudden detection of a spatially isolated A. planipennis outbreak approx. 520 km far north-westward from Tver' (in Saint Petersburg) suggested that A. planipennis most likely had arrived at Saint Petersburg not by gradual stepwise (flying tree-to-tree) expansion of its continuous invasive range in Tver' City, but as a result of its accidental introduction by means of, e.g., "insect-hitchhiked" vehicles, transported plants for planting, and/or other commodities. The proximity of the reported A. planipennis outbreak to the borders of the EU (approx. 130 km to Estonia and Finland) requires urgent measures for its containment and control, and constant monitoring

Ophiostomoid fungi of conifers in Siberia

Paper deals with current problems and perspectives of studies on ophistomotoid fungi in Russia. Intensive investigations of ophiostomoid fungi in all countries of Northern Eurasia can be explained by their vast economic significance. V. N. Sukachev Institute of Forest, Siberian Branch of the Russian Academy of Sciences is the only one research institution in Russian Federation where these studies are implementing in full scale. A list of phytopathogens associated with main pests of Siberian forests is compiled; ecological peculiarities of their interactions were studied. Such species as Ips typographus, Ips subelongatus, Tomicus piniperda, Ips acuminatus and Monochamus urussovi are among these pests. Nowadays multidiscipline study on interaction within an invasive complex of four eyed fir bark beetle Polygraphus proximus and few associates fungal species on firs is conducted. Its’ results will help to understand adaptation mechanisms of both groups of invaders (bark beetles and fungi) to the new environment.Работа выполнена при финансовой поддержке РФФИ (проект 14–04–01235а)

North-Westward Expansion of the Invasive Range of Emerald Ash Borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) towards the EU: From Moscow to Saint Petersburg

Agrilus planipennis is a devastating invasive pest of ash trees in European Russia, Ukraine, and North America. To monitor the north-western limit of its European invasive range, in June 2018 we established 10 study plots along the federal highway M10 (Russia) that runs between Moscow and Saint Petersburg through Tver’ City (approx. 180 km from Moscow), and lined with ash trees. On each plot, 2–4 Fraxinus pennsylvanica trees with heights ranging 6.1–17.0 m and diameters ranging 7.0–18.0 cm were girdled, i.e., 50 cm of their bark were removed. The study plots were visited and girdled trees were examined in September and November, 2018, and in October, 2019. Observations revealed that the current continuous north-western limit of A. planipennis range in European Russia coincides with the north-western border of Tver’ City and this range limit has not distinctly shifted north-westward during 2015–2019. In spite of the rich food supply (due to abundant F. pennsylvanica and F. excelsior plantings) in Tver’ City and along roads going to and from, the population density of A. planipennis in the area is currently low. Recent (September 2020) sudden detection of a spatially isolated A. planipennis outbreak approx. 520 km far north-westward from Tver’ (in Saint Petersburg) suggested that A. planipennis most likely had arrived at Saint Petersburg not by gradual stepwise (flying tree-to-tree) expansion of its continuous invasive range in Tver’ City, but as a result of its accidental introduction by means of, e.g., “insect-hitchhiked” vehicles, transported plants for planting, and/or other commodities. The proximity of the reported A.planipennis outbreak to the borders of the EU (approx. 130 km to Estonia and Finland) requires urgent measures for its containment and control, and constant monitoring

Mesostructure of yttrium and aluminum basic salts coprecipitated from aqueous solutions under ultrasonic treatment

The influence of ultrasonic treatment on the micro and mesostructures and fractal characteristics of amorphous powders of yttrium and aluminum basic salts (precursors for the synthesis of neodymiumacti vated yttrium–aluminum garnet, Nd:YAG, which were coprecipitated from aqueous solutions by different precipitants, namely, aqueous solutions of ammonia and ammonium bicarbonate) is studied. It is established that ultrasonication applied during the precipitation of the aforementioned powders does not significantly change the structure of the obtained materials but always leads to the formation of structures with a less homogeneous nuclear density, i.e., a more developed surface area. Moreover, the ultrasoundassisted precip itation of the hydroxocompounds by ammonium hydrocarbonate results in a certain increase in the surface fractal dimension and the degree of aggregation for massfractal aggregates of particles