It is presented the researches results for defeated potato tubers growing and developing the cultivar’s yield on the microelement’s feeding background (boron, copper, manganese). The positive microelement’s impact was shown on their input into the soil during the potato planting and two following nutritions on the saving the affiliated tubers.

The main criteria for the functioning of agronomic phytocoenosis are indicators of their economic and energy efficiency. In particular, the issues of manufacturability and rational use of sown areas during the growing season characterize the level of agronomic culture in a particular geographical area. Under these conditions, it is important to study the possibility of joint cultivation of agricultural plants, which will reduce energy consumption, improve the phytosanitary condition of crops and increase the profitability of agricultural production. When growing tomatoes in compatible crops, it is necessary to take into account not only aspects of technology, but also the interaction of plants with each other at the level of physiological and biochemical processes. That is why allelopathic relationship between plants, due to the physiologically active substances they secrete at the initial stage of ontogenesis, is not without the interest. It is the scientific basis for the development of sound crop rotation and mixed (compacted) crops, and also helps to increase the productivity of agro- and natural coenoses in order to prevent soil fatigue in monoculture, control weeds, pests, phytopathogenic organisms, etc. Allelopathic substances (collins) of some plant species cause different reactions to other species: some of them have active growth, others have suppressed growth processes, and still others remain neutral to such effects. The stimulating effect is manifested in the awakening of seeds, strengthening of growth processes and the formation of seedling organs. In future this fact will lead to the activation of plant development and an increase in their productivity. At the same time, mutual oppression of plants cannot be ruled out, which can be detected during laboratory studies using biological tests. Field studies of compatible (compacted) crops of tomato with other plants (sugar corn, shallots) were performed using allelopathic testing methods according to Grodzinsky. The expediency and economic efficiency of growing tomatoes in compatible crops with shallots on a green feather have been experimentally proved using statistical methods.

Sunflower (Helianthus annuus L.) is among the three most significant oilseedplants in the world (along with, soybean and rapeseed) and one of the two mostproduced oil crops in the European Union, together with rapeseed. Over the pastdecade, Ukraine has maintained its position as leading producer and exporter ofsunflower seeds and ranks first for sunflower oil consumption globally. A recentUnited States Department of Agriculture report in 2017 suggest that, Ukrainepresently (2015−2016) ranks first in sunflower production globally with a 29.3 %share of total world sunflower output of 40.57 million metric tons. Respectively,Russia and the European Union are currently ranked second and third, with a shareof 22.6 % and 18.9 %, followed by Argentina and China that produced 6.7 % each.The main goal in sunflower breeding is to create hybrids with high geneticpotential for seed yield above 5 t/ha, but environmental factors seems to limitcurrent sunflower yields to the production range of 1.5–3.0 t/ha. In this study,however, we report new sunflower varieties and hybrids in Ukraine that yield evenslightly above 3 t/ha. Thus, a unique sunflower production technology for theforest-steppe of Ukraine for instance now provides sunflower seed yields of 2.9-3.5t/ha. This became possible after the introduction of new high-yielding varieties andhybrids, and the improvement of sunflower cultivation technologies for specificnatural and climatic zones. Hence, further increases in global sunflower seedsoutput mainly from Ukraine are expected without expansions in limited agriculturallands.

Goal. To do analyze phitosanitary state of wart potato sources in Carpathian region of Ukraine with determining infectious load of soil. Identify existing anti-cancer patatoes in Ukraine. Methods. The selection of soil’s samples for zoosporangia of wart pathogen was provided by standard method as per DSTU 3355-96. The sample’s selection points fixed by GPS-navigator Garmin eTrex Legend. The potato wart zoosporangia extraction was conducted by floatation in solution of sodium iodide. The solution Coomassi blue G-250 used for zoosporangia viability determining. Results. Of potato wart pathogens infectious load in Carpathian region of Ukraine 2016—2018 showed the different level of zoosporangia soil’s infection in researched areas. In the hearths of the Chernivtsi region the infectious load was reached 56—68 zoosporangia/1g in sources of Carpathian region, 42—48 zoosporangioa was in the sources of Zakarpattia region, 40—45/1g zoosporangia was determined in Ivano-Frankivsk region, 49 zoosporangia /1g was determined in town Turka Lviv region. The common (D1) pathotype and four aggressive pathotypes of wart potato: 11 (M1) - Mizhgirrya, 13 (R2) - Rachiv, 18 (Ya) - Yasynya and 22 (B1) - Bystrytsya were determined by pathotypes identification in old sources of Zakarpattia, Ivano-Frankivsk, Lviv and Chernivtsi region Conclusions. Analysis of phitosanitary state of wart potato sources in Carpathian region of Ukraine showed the different level of soil’s infectious load in researched areas. There is a common pathotype (D1) and 4 aggressive pathogen disease in Ukraine for present time. The identification of Ukrainian wart pothotypes is planned to identify by European potato cultivar test-assortment usage in perspective.

The mustard variety Felicia was used to analyze the response and compensation effects of growth and physiology under drought stress and rehydration conditions at the seedling stage. The seedlings were exposed to different levels of drought stress simulated by polyethylene glycol (PEG). The growth parameters, fresh weight, chlorophyll fluorescence, and antioxidant system were measured. The results showed that drought stress inhibited the growth of roots and shoots and reduced the performance of photosystem II (PS II). After rehydration, the root length and fresh weight of plants rapidly increased, and the performance index (PI ABS ) was found to be higher compared with the control, which suggested a compensative effect. The chlorophyll content was significantly reduced under moderate and severe drought stress.However, it increased under mild stress conditions. After rehydration, the chlorophyll content under moderate and severe stress did not return to the levels of control, and there was no significant difference between mild stress and the control. Under drought stress, the activities of antioxidant enzymes and content of malondialdehyde (MDA) increased significantly in the leaves. After rehydration, MDA and the activities of antioxidant enzyme were higher than those of the control group, particularly under moderate and severe stress. Therefore, these results suggest that mustard is strongly adapted to mild drought stress through the efficient activities of antioxidant enzymes activity and photosynthesis, as well as its rapid recovery after rehydration.