T. M. Kolombar’s research while affiliated with Oles Honchar Dnipro National University and other places

Porcellio laevis Latreille, 1804 plays a significant role in soil formation processes, in particular in the decomposition of organic residues. It is also an important component of food chains. At the same time, when present in excessive numbers, woodlice can act as secondary pests, particularly in the storage of plant products. This study examines the effects of 20 natural aromatic plant materials – spices, essential oils, and plant extracts – on the locomotor activity of P. laevis. The movement of the individuals was analyzed over a 3-min period using a T-shaped experimental chamber. Most of the tested materials significantly reduced the isopod motility compared with the control conditions. Notably, nutmeg, coffee, and basil demonstrated both attractant and deterrent effects, while allspice, clove, essential oils of Mentha piperita and Melaleuca alternifolia, and extract of Petroselinum crispum acted as repellents. These findings highlight the potential of natural aromatic compounds as environmentally friendly means to regulate isopod populations without the use of toxic insecticides.

The global climate changes are causing an increase in the number and harmfulness of slugs. Deroceras agreste (Linnaeus, 1758) (Stylommatophora, Agriolimacidae) is a polyphagous phytophage that damages over 150 species of plants, including many vegetables , cultivated berries and grasses. Other than decrease in yield, slugs cause deterioration of consumer qualities of the products, promote infections of plants, and are intermediate hosts of some parasites of mammals and birds. Thus, slugs impose great losses on agricultural farming, and therefore the objective of our study was determining the variability of locomotor activity of D. agreste slugs in reaction to aromatic substances. We determined repellent or attractive effects of those substances for the purpose of further using the obtained data for plant protection. We tested 52 substances and their mixtures, which were conditionally divided into the following groups: chemical solvents, plant extracts, aromatizers, organic acids and synthetic cosmetic additives. Only dimethyl sulfoxide could be identified as an attractant. All the rest of the substances increased the speed of the slugs to various degrees, but had no significant effect on the direction of the animals' movement. Gasoline increased the speed of the slugs' movement by 3.20 times, xylene by 4.56. The most effective organic acids and aromatizers to increase the moving speed of slugs were avobenzone and formic acid: the first caused a 2.83-fold increase in the moving speed, the other a 3.16-fold increase. Only one of 13 aromatic substances changed the direction of the slugs' movement during the experiment-β-ionone. As with the plant extracts, the highest effect on locomotor activity of slugs was exerted by tree bark of Quillaja saponaria (3.64-fold) and Aesculus hippocastanum extract (4.33-fold). Furthermore, together with Capsicum frutescens, they changed the direction the mollusks were moving in, and therefore could be used as repellents. Synthetic cosmetic additives hydrolyzed silk and chrysalide oil exerted the greatest effects on the lcomotor activity of slugs (3.16 and 3.20 times, respectively). A total of 78.6% of the slugs moved away from chrysalide oil, and thus this oil may be suggested as a repellent, as well as mousse de babassu and cocamidopropyl betaine (84.6% and 78.6%, respectively). Therefore, a large amount of the tested substances to one or another extent made the slugs move faster, but most of them did not alter the direction in which the slugs were moving.

Parasites of agricultural crops cause significant losses of quality and decrease in the profitability of agricultural production. Complex measures against pests are aimed both at termination of parasites and prevention of repeated infection of plants. One of the most progressive ways of protecting plants against harmful insects is the use of entomopathogenic nematodes. This method is most expedient in the conditions of organic arable farming. The results of our study reveal the impact of the fertilizers in various concentrations on the vitality of nematode larvae (L 3) of four species (Steinernema feltiae, S. kraussei, S. carpocapsae and Heterorhabditis bacteriophora) and the possibility of their combined application for the treatment of plants. Mineral fertilizers and stimulators of growth of plants in 1% concentration insignificantly reduced the vitality of larvae, allowing them to be applied at the same time. We determined the tolerance of invasive larvae to pH for S. carpocapsae equaling рН = 0.9-13.4; optimum values of рН without reliable increase in the mortality during 24 h-рН = 1.3-12.8. Increase in the vitality of larvae (L 3) of entomopathogenic nematodes was studied. The survivability of the cultures of larvae increased during the use of solutions of vitamins С, В 1 , В 6 , В 12. We determined the influence of 21 pigment colourings on larvae (L 3), the lowest effect on the vitality of nematode larvae was exerted by pigment bases Abrikos (7.0-10.8% mortality during 24 h), Zolotoi Pesok (6.0-11.8%), Pudra Ananasa (7.7-13.4%), and complex DMAE (7.6-17.4%). The results we obtained allow development of recommendations for agriculturalists for combined use of entomopathogenic nematodes with various substances and also improving the vitality of invasive nematodes.

Cereals are the basis of world crop production. In Ukraine, winter wheat crop plays a rolea strategic agricultural product. The basis of food security and the formation of the national export potential depend on this crop species. Wheat has a steadydemand on the internal and foreign markets. In the structure of crops, it occupies about 6 million hectares, which is more than 22% of all cultivated areas and almost 42% of grain crops. Like most other crops, cereals serve as food supply for a wide range of insect phytophages. Conventionally, the entire fauna of endangeredspecies can be divided into multiphages, oligophages and monophages. Cereal plants are damaged by insects during the entire growing season, from germination to harvesting. There are more than 230 species of wheat insects. Territory of the steppe zone of Ukraineamounted 17 most common and criticallyendangeredspecies on. The degree of harmfulness of each species in different vegetation periods is not the same. The goal of the paper was to reveal a current state of the most common endangeredspecies (wheat phytophages) within Dnepropetrovsk, Poltava and Zaporizhia Oblasts, and to assess a degree of their harmfulness (according to literature data). Harmful insects were accounted using conventional manual sampling method. The accounting was carried out on plots of 50 × 50 cm (0.25 m2), staggered evenly over an entire field, using a frame placed onto the plants randomly. All wheat stems inside the frame were shaken to a ground surface, and the number of harmful insects was counted. At the same time, the upper layer of soil (0–25 cm) was visually inspectedfor the presence of insect larvae and imagos. 16 samples were collectedon each field. The average number of each insect species per 1 m2 of wheat crops was calculated. As a result of 50 fields survey in Dnepropetrovsk, Zaporizhia and Poltava Oblast, a list of the most common endangeredspecies (wheat phytophages) in the steppe and forest-steppe zones was created. It includes 17 species belonging to 7 families from three orders. The most recorded representatives of Coleoptera order were 12 species, four species from Hemiptera order and one from Thysanoptera. On average, three species of wheat phytophages belong to each of the families; the largest number of endangeredspecies is represented by Scarabaeidae family. Among the identified phytophages, the most common were Harpalus rufipes (De Geer, 1774) 88% of infected fields, Zabrus tenebrioides (Goeze, 1777) 78% and Anisoplia austriaca (Herbst, 1783) 72%. Specimenof endangeredspecies as Eurygaster integriceps (Puton, 1881) were found on 34 fields, Haplothrips tritici (Kurdjumov, 1912) on 22 fields, Oulema lichenis (Heyden, 1879) on 21 fields, and Aelia acuminata (Linnaeus, 1758) on 18 fields. A brief description of each of 17 endangeredspecies was presented, taking into account their harmfulness in different periods of wheat vegetation. The degree of harmfulness of each species in different vegetation periods is not a same. A distinction is made between the early period, spring and the second half of the growing season. Early vegetation period is from the seedling emergence to the period of grass tillering. During this period, an impact of harmful insects is particularly dangerous, and a damage they cause can lead to a death of plants over large areas. The species most dangerous for wheat at this time are Harpalus rufipes and Zabrus tenebrioides. It is difficult to establish a clear distinction between the impact of endangeredspecies on plants during different periods of vegetation. With a beginning of spring vegetation, Oulema lichenis, Phyllotreta vittula and Chaetocnema aridula and Tropinota hirta are added to the above-mentioned species. Harmfulness during this period consists will be represented by leaf blade damage. The middle of vegetation coincides with an ear formation and grain filling phases. The most active endangeredwheat species during this period are considered to be Haplothrips tritici, Opatrum sabulosum, Pedinus femoralis and Blaps lethifera. The quality indicators of a cereal crop yield are reduced by Eurygaster integriceps and E. maura, Aelia acuminata and A. rostrata. Before the harvest the grain is damaged by various Scarabaeidae, in particular Anisoplia austriaca, A. agricola , A. segetum. As a result of controlling the number and species composition of endangeredwheat species, it is necessary to adapt the application of integrated methods of wheat protection to the soil and climatic conditions of the steppe and forest-steppe zones of Ukraine.

Parasites of agricultural crops cause significant losses of quality and decrease in the profitability of agricultural production. Complex measures against pests are aimed both at termination of parasites and prevention of repeated infection of plants. One of the most progressive ways of protecting plants against harmful insects is the use of entomopathogenic nematodes. This method is most expedient in the conditions of organic arable farming. The results of our study reveal the impact of the fertilizers in various concentrations on the vitality of nematode larvae (L3) of four species (Steinernema feltiae, S. kraussei, S. carpocapsae and Heterorhabditis bacteriophora) and the possibility of their combined application for the treatment of plants. Mineral fertilizers and stimulators of growth of plants in 1% concentration insignificantly reduced the vitality of larvae, allowing them to be applied at the same time. We determined the tolerance of invasive larvae to pH for S. carpocapsae equaling рН = 0.9–13.4; optimum values of рН without reliable increase in the mortality during 24 h – рН = 1.3–12.8. Increase in the vitality of larvae (L3) of entomopathogenic nematodes was studied. The survivability of the cultures of larvae increased during the use of solutions of vitamins С, В1, В6, В12. We determined the influence of 21 pigment colourings on larvae (L3), the lowest effect on the vitality of nematode larvae was exerted by pigment bases Abrikos (7.0–10.8% mortality during 24 h), Zolotoi Pesok (6.0–11.8%), Pudra Ananasa (7.7–13.4%), and complex DMAE (7.6–17.4%). The results we obtained allow development of recommendations for agriculturalists for combined use of entomopathogenic nematodes with various substances and also improving the vitality of invasive nematodes.

Measures against pests should be performed in the context of integrated management of agricultural crops and complex control of pests. Therefore, use of ecologically safe approaches is the best option. Essential oils of plants can make an impact on the main metabolic, biochemical, physiological and behavioural functions of insects. We evaluated the effect of 18 essential oils and 18 dried plants on migratory activity of Sitophilus granarius (Linnaeus, 1758) and Tenebrio molitor Linnaeus, 1758 in conditions of laboratory experiment. Notable repellent activity against S. granarius was exhibited by Citrus sinensis and Picea abies. Repellent action against T. molitor was displayed by dried and cut leaves of Origanum vulgare and Eucalyptus globulus, and also essential oils from Juniperus communis, Р. abies, Pterocarpus santalinus, C. sinensis and C. aurantiifolia. Therefore, out of 18 studied essential oils, only two samples had a notable biological effect on migratory activity of S. granarius and five samples – on T. molitor. These data indicate a possibility of using essential oils or their main components as ecologically safe natural repellents against pests of stored wheat and products of its processing.

Annually in the world, insect pests kill 10–15 % of the crop yield, which in the face of increasing humanity creates a global problem for food security. For the territory of Ukraine in some years, the loss of wheat yields reach 25 % and, in the face of this tendency, real risks to the security of the state are created. Considering that the agrarian trend of the state development has been increasing in recent years, the development of grain-adapted to the ecological and climatic conditions of Ukraine is a priority direction of the development of domestic agriculture. And the development of new environmentally friendly methods of controlling pests of wheat using parasitic organisms will become a fundamentally new and pressing issue in the development of organic production in the country. The general list of pest species that can cause serious wheat yield and forage reduction in Ukraine includes more than 230 names, but only 18 species are able toentail the biggest losses. Among them belong to the order Coleoptera. One insect species is usually a host of several species of mites, nematodes and up to ten species of gregarines and microsporidia. Unfortunately, the taxonomic composition of parasites of phytophagous pets of wheat in Ukraine has not been thoroughly investigated. We studied the interrelation between parasites of 4 phytophagous insects of wheat as well as of 14 insect species found in granaries. The study of the species composition of parasitic organisms of wheat and grain pests is based on the study of the elementary part of the consortium ecosystem, where they act as second order consortia. Phytophagous parasites of wheat and collar pests of cereals, as second-order consorts, have been fragmented worldwide. The purpose of this work is to determine the species composition of gregarine as a component of wheat consortium for their further use in the creation of integrated methods of protection of wheat and products of its processing. As a result, 28 species of gregarines were registered, which belong to seven families (Didymophyidae, Ophryocystidae, Hirmocystidae, Lipotrophidae, Stylocephalidae, Actinocephalidae and Gregarinidae). On the average, 1–2 species of gregarines parasitize in one pest species. 7–10 species of parasites were identified in some insects of the family Tenebrionidae (Tenebrio molitor Linnaeus, 1758 and Tribolium confusum Jacquelin du Val, 1863). Each presented parasite is characteristic of 1–2 species of pests, but there are species of gregarines that infect up to four species of model species, such as Gregarina cuneata Stein, 1848. The largest number of individuals who are infested with gregarines belong to such families as Tenebrionidae and Dermestidae (38,6 % and 36,0 % of the total number of species, respectively). On pests – phytophages parasitizes about 8 species of gregarine families Stylocephalidae, Gregarinidae, Actinocephalidae. For barns pests are recorded barnacles of all 7 families.

Pest control should be ecologically-based, therefore use of ecologically safe approaches is the best variant. Essential oils of plants can affect the main metabolic, biochemical, physiological and behavioural functions of insects. In the experiment, we evaluated the influence of 20 essential oils on migration activity of imagoes of Tribolium confusum Jacquelin du Val, 1863 in the conditions of a laboratory experiment. Notable repellent activity against T. confusum was exhibited by essential oils of Jasminum officinale and Thuja occidentalis. Essential oils of Zingiber officinale and Cedrus atlantica had an attractant effect on imagoes of T. confusum. Essential oils of Rosmarinus officinalis, Melaleuca alternifolia, Lavandula angustifolia and Cinnamomum verum exhibited repellent properties while essential oils of Juniperus communis and Citrus sinensis had an attractant effect on the pests. Therefore, out of 20 studied essential oils, only four samples had notable biological effect on migration activity of T. confusum imagoes. These data indicate the possibility of using essential oils or their main components as ecologically safe natural repellents against pests of stored wheat and products of its processing.