Purpose. To determine morphological and morphometric features of vegetative and generative organs of Persica species and varieties under the conditions of the Forest-Steppe zone of Ukraine for further use in breeding.Methods. Biological (morphological analysis) and statistical (processing of morphometric parameters) ones.Results. It was found that except ternate multiple buds, in peach hybrid ‘Suputnyk’collateral buds were prevalent which was not common to other tested varieties and species. Buds of each species and variety have a certain number of scales. The most scales were observed in ‘Suputnyk’. Pubescence of abaxial side of the leaf in P. davіdiana and ‘Suputnyk’ plants was not revealed. Species of P. vulgaris (‘Pecherskyi’, ‘Antotsianovyi’, ‘Poleskyi’) was characterized by increase in size of leaf blades, flowers and fruits. The distinctive features of P. davidiana and ‘Suputnyk’ are that stamens were accumulated in their flowers while in P. vulgaris they are branched. Raphe of a P. vulgaris stone protrudes above the edges of the bordering creases and consists of a number of narrow plates.Conclusions. For the breeding purposes, plants have an advantage for some basic criteria: the most flower buds that is common to interspecies hybrid ‘Suputnyk’; increase in photosynthetic productivity of the leaf apparatus to be typical for the variety ‘Pecherskyi’; large fruits that ‘Pecherskyi’ variety is noted for; intense red color of fruits that is inherent feature of ‘Antocianovyi’ variety.

Purpose. To study the morphological features and determine the biometric indices of leaves of English roses. Methods. Field, morphological, descriptive, biometric. Morphological descriptions were carried out in accordance with the Atlas of morphological features of rose varieties (Rosa L.) (2009) and the Illustrated Guide to Flowering Plant Morphology (2004). Results. The morphological features of the leaves of English rose varieties were determined. Quantitative (length of complex leaf, number of leaf plates, area of leaflet, total leaf area) and qualitative (leaflet shape, leaflet edge shape, leaflet base shape, leaflet tip) were studied. Varieties of English roses that have maximum and minimum values for these indicators were highlighted. Conclusions. The morphological features were revealed and the biometric indicators of the leaves of English roses from the collection of the State Dendrological Park “Alexandria” NAS of Ukraine were determined. The amplitude of variability of morphological characters of the studied varieties was determined. Peculiarities of the morphological structure and biometric parameters of leaves of English rose varieties can be diagnostic signs for determining varieties within the boundaries of the species. Plants with increased photosynthetic productivity of the leaf apparatus, which is characteristic of the ‘James Galway’ and ‘A Shropshire Lad’ varieties, have an advantage in landscaping.

Purpose. To determine the features of the leaf surface area formation and the dynamics of growth of the vege­tative mass of various sainfoin species depending on the influence of mineral fertilizers and inoculation. Methods. Field, laboratory, statistical. Results. In the course of experimental studies, the morphological features of plants in the process of growth and development of various sainfoin species were studied. As our studies showed, all sainfoin species had different plant densities, which accordingly affected the leaf surface area. In the budding phase, the leaf surface area of plants of the first year in continuous cultivation ranged from 17.01 to 24.3 thousand m2/ha on average over three years; in particular, from 18.06 to 24.3 – for common sainfoin; 17.6–20.5 – for transcaucasus sainfoin and 17.1–20.3 thousand m2/ha – for sand sainfoin. The maximum leaf surface area of the plants of the first year of cultivation, regardless of its species, was observed during flowering with the application of complete mineral fertilizer (N45P60K90). In areas without fertilizer this figure was much lower. In the experiments, an increase in the leaf surface on all three studied species and sainfoin varieties from the first to the third year of their cultivation was clearly observed. According to the results of gross productivity for 2 mowings, it was found that common sainfoin forms the maximum increase of top with complete mineral fertilizer and seed inoculation – 43.03 t/ha. Conclusions. The productivity of sainfoin crops depended mostly on the application of complete fertilizer at a dose of N45P60K90 + inoculation of seeds. To a much lesser extent, the species of sainfoin and the cutting height of the first mowing of the grass stand affected its productivity. It was revealed that the greatest dynamics of vegetative mass growth was observed in common sainfoin, and the smallest was recorded in sand sainfoin.

Purpose. To investigate the variability of plant biometrics of cutting lettuce (Lactuca sativa L.) varieties depending on the concentration of microfertilizer Avatar-1. Methods. Field study, biometric technique, comparative approach, statistical evaluation, generalization. Results. Dependence of the plant height, the diameter of the leaf rosette, the number of leaves per plant, the leaf area of plants on the concentration of microfertilizer Avatar-1 was defined. Investigations of cutting lettuce ‘Afitsyon’ and ‘Concord’ varieties by Dutch breeding were conducted in 2016–2017 in the collection sites of the department of vegetable growing in the scientific-experimental field “Fruit and vegetable garden” of the National University of Life and Environmental Sciences of Ukraine. In order to determine dependence of plant biometrics of cutting lettuce varieties on the concentration of complex microfertilizer Avatar-1, the following scheme was used for the both varieties: variant 1 – water (control); variant 2 – 0,10% solution; variant 3 – 0,25% solution; variant 4 – 0,50% solution. Plants were treated with microfertilizer three times during the vegetative period. Alterations of plant biometrics of cutting lettuce ‘Afitsyon’ and ‘Concord’ varieties depending on the concentration of complex microfertilizer Avatar-1 was studied. Conclusions. It was found that in case of three-time plant treatment with complex microfertilizer Avatar-1 at the time of harvesting, the best plant biometrics was registered in variant 3 (concentration 0,25%) for the both ‘Afitsyon’ and ‘Concord’ varie­ties of cutting lettuce. The height of plants of the cutting lettuce in ‘Afitsyon’ variety exceeded this figure in ‘Concord variety by 1,1–1,4 cm. The concentration of microfertilizer had no significant effect on the diameter of the leaf rosette of ‘Concord’ variety (25,1–25,9 см). The diame­ter of the leaf rosette of ‘Afitsyon’ variety was 26,0–28,7 cm. In cutting lettuce, the largest leaf area per plant was registered in ‘Afi­tsyon’ variety (3516.5 cm2/plant) in case of plants treatment with 0,25% solution of complex microfertilizer Avatar-1 that exceeded this figure in ‘Concord’ varie­ty by 660 cm2/plant. The best plant biometrics of cutting lettuce of the studied varieties and optimal concentration of complex microfertilizer Avatar-1 (0.25% solution) was defined that is important for improving agricultural cultivation techniques.

Purpose. Comparative studies of the photosynthetic apparatus of winter wheat varieties of modern and earlier breeding in the relation to their productivity. Methods. Field, pot experiment, biometrical, gas analysis, analytical and statistical ones. Results. It is found that the modern high-yielding winter wheat varieties have a higher rate of flag leaf photosynthesis during generative period of development, particularly at grain filling period, improved ability to store assimilates in stem and effectively use them later for grain growth. The modern varieties form crop canopy with greater leaf area and chlorophyll indexes and larger photosynthetic capacity and maintain functional activity of photosynthetic apparatus longer at the end of the growing season. Conclusions. The superiority for grain productivity of modern high-yielding wheat varieties, originated from the Institute of Plant Physio­logy and Genetics, NAS of Ukraine, over varieties released before the “green revolution”, results from increased capacity and durability of functioning the crop photosynthetic apparatus, higher CO2 assimilation rate and optimization of source-sink relations in whole plant.

Purpose. To study the influence of fractional composition of seed material on productive properties of spring rape seeds of the ‘Magnat’ variety and ‘MVM’ (‘Gladiator’) variety sample. Methods. Field investigations, laboratory tests, statistical analysis. Results. During 2013–2014, the influence of sown seeds of different size fractions (up to 2,5 g; 2,6–3,5 g; 3,6 g and more) on the indices of productivity of spring rape varie­ties was studied. It was found that over the years of study field germination of sown fractions of seeds in ‘Magnat’ variety averaged 83.5%, in ‘MSM’ variety sample – 86.7%. During the periods of seedling emergence and harvesting, the density of spring rape crops varied depending on relevant fraction of sown seeds. In the ‘Magnat’ variety, photosynthetic potential of crops ranged from 1.1 to 1.3 million m2/ha, in ‘MSM’ variety sample – from 1.2 to 1.6 million m2/ha. Depending on the seed fractions applied, ‘Magnat’ variety crops during the gro­wing season accumulated organic biomass from 2.05 to 2.36 g/m2 per day, ‘MSM’ sample variety – from 1.83 to 2.10 g/m2 per day. Conclusions. It was established that different fractions of spring rape seeds sown in the Northern Forest-Steppe zone of Ukraine affected the indices of germinating energy and laboratory germination, crop density formation, leaf surface area and intensity of photosynthesis process (crop photosynthetic potential, net photosynthesis performance). The highest indices of productivity and yield in the ‘Magnat’ variety was ensured by large-seeded fraction (3,6 g and more), in the ‘MVM’ (‘Gladia­tor’) sample variety – by small-seeded fraction (up to 2,5 g).

In 2011 to 2013 a study was completed for the impact of varying rates of fertilizing onto the indices of productivity for barley agrophytocenosis of Helios and Commandor, in particular, such its components as a number of productive stems, number of seeds per ear, potential biological activity of ear and photosynthetic apparatus. It is found that the level of spring barley agrophytocenosis productivity is subject both to varietal peculiarities and the rate of mineral fertilizer application. When applying N 60P 60K 60 і N 90P 90K 90 the highest potential and biological productivity of Helios and Commandor was recorder as compared against the control. Impact of varying application rates for fertilizers onto the components of ear biological productivity has been scrutinized. The qualitative composition of ear is a clear expression of variety phenotype and identifies the level of biological yield for spring barley. Application of N 60 P 60 K 60 і N 90 P 90 K 90 mineral fertilizers fairly increased the average leaf surface, photosynthetic lead capacity of varieties in 2 to 2.5 times, as well as FAR efficiency coefficient in 1.5 to 2.0 times as against control that thus contributed to the development of highest biological yield of Helios variety phytomass at the level of 14.9 to 15.0, grain – 7.8 to 8.0 ton per ha and, respectively, 12.7 and 7.5 tons per ha for Comandor variety.

The article presents the results of the laboratory investigation of the influence of high temperatures on water regime of red currant in Institute of Fruit Selection. It shows the dependence of water loss by leaves on the phenophase of plant development. High water loss by leaves occurs during the phase of ripening berries (July). Low water loss is noted during the active growth of shoots (June). Red currant genotypes: «Valentinovka», «Bayna» have a high percent of water loss in June and July. Genotypes «Shedraya», «Gollandskay krasnay», «Orlovchanka», «Dar Orla», «Selyanochka», «Osipovskay», «Belka» and «Jonker van Tets» have a low percent of loss water. The loss of water at the temperature shock is the important protective mechanism from over heat and death of plants. The results of the investigation of a degree of water restoration by red currant leaves in the periods of berry ripening and active growth of shoots are given. The most part of genotypes of red currant leaves have a high percent (>50%) of water restoration. Genotypes «Selyanochka» ,«Orlovchanka», «Dana», «Shedraya», «Belka» have a more 100% of water restoration. On the ground of the obtained results the following genotypes: «Belka», «Selyanochka», «Gollandskay krasnay», «Shedraya», «Orlovchanka», «Dar Orla», «Osipovskay» and «Jonker van Tets» are mostly heat resistant.

Purpose. To determine morphological and morphometric features of vegetative and generative organs of Persica species and varieties under the conditions of the Forest-Steppe zone of Ukraine for further use in breeding. Methods. Biological (morphological analysis) and statistical (processing of morphometric parameters) ones. Results. It was found that except ternate multiple buds, in peach hybrid ‘Suputnyk’collateral buds were prevalent which was not common to other tested varieties and species. Buds of each species and variety have a certain number of scales. The most scales were observed in ‘Suputnyk’. Pubescence of abaxial side of the leaf in P. davіdiana and ‘Suputnyk’ plants was not revealed. Species of P. vulgaris (‘Pecherskyi’, ‘Antotsianovyi’, ‘Poleskyi’) was characterized by increase in size of leaf blades, flowers and fruits. The distinctive features of P. davidiana and ‘Suputnyk’ are that stamens were accumulated in their flowers while in P. vulgaris they are branched. Raphe of a P. vulgaris stone protrudes above the edges of the bordering creases and consists of a number of narrow plates. Conclusions. For the breeding purposes, plants have an advantage for some basic criteria: the most flower buds that is common to interspecies hybrid ‘Suputnyk’; increase in photosynthetic productivity of the leaf apparatus to be typical for the variety ‘Pecherskyi’; large fruits that ‘Pecherskyi’ variety is noted for; intense red color of fruits that is inherent feature of ‘Antocianovyi’ variety.

Purpose. Providing a scientific rationale for the practical application of analysis of variance elements to determine the range of morphological and value for cultivation and use (VCU) characteristics of Romaine lettuce ‘Skarb’ variety. Results. The Romaine lettuce ‘Skarb’ variety was identified by the type of display of quantitative (QN) identification characteristics. VCU characteristics of the var. longifolia L. varieties were determined and statistically processed. The author focused on practical application of histogram and variation curve of phenotype morphological characteristics when performing the uniformity test. The correlation between quantitative characteristics of lettuce leaf and head was observed when plant productivity was developing. Romaine lettuce yield value was verified statistically. Thresholds were established for the indices under study, confidence intervals were defined over the years of study. Conclusions. The use of Lewis stability factor (S.F. = Xmax/Xmin) allowed to establish the stability of each characteristic display. Practical application of the histogram and variation curve for determining code of display of quantitative morphological characters and the range of VCU characteristics of the Romaine lettuce ‘Skarb’ variety was scientifically grounded.