Iryna Sytnikova’s research while affiliated with Chernivtsi National University and other places

Invasions of species into ecosystems cause their transformation and, in certain cases, their degradation. The study was carried out to determine the extent of the invasion of Cydalima perspectalis (Walker, 1859). For this purpose, the following aspects were analyzed: distribution of the species in different countries of the worldі, history of invasion of the pest in Ukraine, degree of damage to plantations of different box (Buxus L.) species and colony density in certain areas. The chronology of the distribution of C. perspectalis was studied using literature sources and international databases: Global Biodiversity Information Facility (GBIF), Delivering Alien Invasive Species Inventories for Europe (DAISIE), European and Mediterranean Plant Protection Organization (EPPO). The information on the history of the species' invasion in Ukraine and in particular in the Chernivtsi region was found in the literature, using the database of the National Biodiversity Information Network (UkrBIN), through questionnaires and personal observations using the route method (counting the number of C. perspectalis on a certain route). The degree of damage to Buxus sp. shrubs was determined visually using a scale. The density of C. perspectalis in each area was assessed by total counts and direct counts in situ with a parallel assessment of habitat size. It was found that the expansion of C. perspectalis beyond its native range began in 2006 from southwestern Germany. In 15 years, the species has occupied the territories of about 40 mainland and island countries of the North American and European continents. Since 2014, after the invasion of the Zakarpattia region, C. perspectalis has begun to spread throughout the Ukrainian territories. Currently, the secondary range of the species is represented by 14 regions. The presence of C. perspectalis has been detected in 16 settlements of Chernivtsi region, where the degree of damage to box shrubs is mostly severe. The density of caterpillars on most bushes is up to 100 individuals/m2, which indicates the high damage of the species. Key words: Cydalima perspectalis (Walker, 1859), invasive species, damage, expansion.

Physical and chemical quality indicators of 65 polyfloral honey samples from three administrative districts of Chernivtsi region in South Western Ukraine were studied. The chosen administrative districts were Putyla (representing the ‘Traditional villages’ stratum), Storozhynets (the ‘Intermediate’ stratum) and Khotyn (the ‘Intensive agriculture’ stratum), which reflect a steep gradient of social and ecological conditions such as land cover and land use, level of economic development, culture and demography. The quality of honey was determined in accordance with the requirements of the Ukrainian national standard and the EU Directive relating to honey (or Codex Alimentarius Honey Standard) by using the following indicators: reducing sugars and moisture content, diastase activity, free acidity, pH, electrical conductivity, hydroxymethylfurfural (HMF) and proline content. The profile of carbohydrates was analyzed, in particular glucose, fructose, sucrose, maltose, trehalose, melezitose, raffinose. The ratio of fructose to glucose (F/G) was determined. All tested samples complied with the international standards for the mass fraction of reducing sugars, diastase activity and hydroxymethylfurfural content. For physical and chemical parameters, the studied honey samples were of high quality. The content of the reducing sugars in the honey samples varied within the range of 66.0–97.6%. The fructose content ranged from 342 to 549 mg/g, and the glucose content variation ranged within 283–517 mg/g. The average fructose/glucose ratio was 1.2 for honey samples from the three studied districts. Besides fructose and glucose, some oligosaccharides, such as maltose, trehalose and melezitose, were found in the examined honey. Melezitose was detected in the honey samples from ‘Traditional village’ (21 samples) and ‘Intermediate’ (5 samples) districts. The total variability of HMF content in the studied 65 honey samples from apiaries in the three districts of Chernivtsi region ranged from 0.19 to 30.8 mg/kg. The minimum moisture content was found to be 16.2% (in the ‘Traditional village’ and ‘Intermediate’ strata), and 22.2% was the maximum (in the ‘Intermediate’ stratum). Our studies have shown that free acidity of the samples varied within the range 13.5 to 58.0 meq/kg. Proline content variability for the three studied geographical areas ranged from 82.3 to 1201.2 mg/kg. The studied samples of honey had a low pH level (~ 3.7), high content of proline (~ 513 mg/kg) and reducing sugars (~ 80%), which indicates its nutritional value and naturalness. Deviations from the honey standards in moisture content, acidity and electrical conductivity was revealed in 8% to 10% of all samples.

The following article is the result of biotesting of ecotoxicological danger of pesticides, which are used in gardening. Ten pesticide preparations were selected for the research, six of them are fungicides: flint-star, chorus, score, stroby, topsin-M and median-extra and four of them are insecticides: bi-58, calypso, mospilan and actara. Toxicity of pesticides was identified through analyzing ten times dilution (1:10) of the recommended solution specified by the manufacturer. Not less than three days old tap water served as control. Daphnia, Ostracoda and Danio were selected as test objects. After 1, 2, 3, 4, 5, 24 and 72 hours of exposure the number of dead animals was visually determined and the percentage of survival of testers was calculated. The toxicity of the pesticide preparations was considered as proven if the percentage of test organisms mortality rate was ≥50%. The scale of pesticide toxicity degree was developed, including the percentage of test organisms mortality during certain exposure time (up to 24 or 48 hours). It can be used to define its acute and toxic effect. According to the biotesting results, flint-star and score are the most toxic among the examined pesticide preparations fungicides for aquatic ecosystems, as they showed ultrahigh and high levels of toxicity for zootests. Carp fishes of the genus Danio showed greater sensitivity to the influence of fungicides and lower to insecticides, while for aquatic crustaceous Daphnia and Ostracoda these features were not detected. The sensitivity of the tested test objects to insecticides decreased in an order: Ostracoda sp.→Daphnia sp.→Danio sp. Comparing the sensitivity of aquatic crustaceous in the process of the pesticides biotesting, it was found out that Ostracoda sp. is more sensitive test object than Daphnia sp. Under the same conditions of biotesting, an absolute immobilization of ostracods is two times higher than the immobilization of Branchiopoda.