Purpose. To develop an algorithm of creation of new highly productive clonal varieties of Salicaceae family representatives with improved agronomic characters that can be used at energy plantations Methods. Field investigations, laboratory analysis, analytical approach, selection method. Results. Flow chart of selection process with representatives of Salicaceae family included the following stages: the Ist stage – creation of primary families (F0); the IInd stage – creation of the second families, or branches; the 222rd stage – interfamily (individually-familial) selection; IVth stage – familial-group selection; the Vth stage – clonal selection (selection of ramets). Conclusions. Breeding process with the use of complex of advanced methods of selection (individual, familial, group and clonal ones) allows to get model populations with high-frequency of valuable alleles and genotypes and with the high level of genetic variety. Due to a negative multi-stage individual intrafamilial and interfamily selection, cleaning of artificial populations from undesirable forms takes place without the substantial decrease of genetic variety level.

Purpose. To develop an algorithm of creation of new highly productive clonal varieties of Salicaceae family representatives with improved agronomic characters that can be used at energy plantations Methods. Field investigations, laboratory analysis, analytical approach, selection method. Results. Flow chart of selection process with representatives of Salicaceae family included the following stages: the Ist stage – creation of primary families (F0); the IInd stage – creation of the second families, or branches; the 222rd stage – interfamily (individually-familial) selection; IVth stage – familial-group selection; the Vth stage – clonal selection (selection of ramets). Conclusions. Breeding process with the use of complex of advanced methods of selection (individual, familial, group and clonal ones) allows to get model populations with high-frequency of valuable alleles and genotypes and with the high level of genetic variety. Due to a negative multi-stage individual intrafamilial and interfamily selection, cleaning of artificial populations from undesirable forms takes place without the substantial decrease of genetic variety level.

Purpose. To estimate genetic resources collection of soft winter wheat plants (new collection accessions) of Ustymivka Experimental Station for Plant Production and select initial material for breeding of adaptive, productive and qualitative soft winter wheat varieties. Methods. Field experiment, laboratory testing. Results. The authors pre- sented results of study of over 1000 samples of gene pool of soft winter wheat from 25 countries during 2001–2005 in Ustymivka Experimental Station for Plant Production of Plant Production Institute nd. a. V. Ya. Yuriev, NAAS of Ukraine for a complex of economic traits. More than 400 new sources with high adaptive properties were selected that combine traits of high productivity and high quality of grain, early ripening, resistance to biotic and abiotic fac- tors (the assessment of samples for 16 valuable traits is given). The selected material comes from various agro-cli- matic zones, including zones of unsustainable agriculture. Conclusions. Recommended sources of traits that have breeding value will allow to enrich high-quality assortment of wheat and considerably accelerate breeding process du- ring development of new soft winter wheat varieties.

Purpose. To estimate genetic resources collection of soft winter wheat plants (new collection accessions) of Ustymivka Experimental Station for Plant Production and select initial material for breeding of adaptive, productive and qualitative soft winter wheat varieties. Methods. Field experiment, laboratory testing. Results. The authors pre- sented results of study of over 1000 samples of gene pool of soft winter wheat from 25 countries during 2001–2005 in Ustymivka Experimental Station for Plant Production of Plant Production Institute nd. a. V. Ya. Yuriev, NAAS of Ukraine for a complex of economic traits. More than 400 new sources with high adaptive properties were selected that combine traits of high productivity and high quality of grain, early ripening, resistance to biotic and abiotic fac- tors (the assessment of samples for 16 valuable traits is given). The selected material comes from various agro-cli- matic zones, including zones of unsustainable agriculture. Conclusions. Recommended sources of traits that have breeding value will allow to enrich high-quality assortment of wheat and considerably accelerate breeding process du- ring development of new soft winter wheat varieties.

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).

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).

Purpose. Defining marker-trait associations of microsatellite markers with specific regions of the genome that control important agronomical traits in the investigated varieties originated in the Plant Breeding and Genetics Institute – National Center of Seed and Cultivar Investigations and entered into the State register of plant varieties suitable for dissemination in Ukraine during different years. Methods. Molecular genetic methods (extraction of genomic DNA, polymerase chain reactions (PCR), electrophoresis of amplification products in polyacrylamide gel), field methods (phenological observations of heading date and analysis of plant height, visual assessment of the colour and length of wheat ear and awns), statistical methods (evaluation of trait means by descriptive statistic instruments of EXCEL package, ANOVA method performed by GLM instrument from AGROBASE 21 package). Results. During four gro­wing years (2010/11, 2011/12, 2012/13, 2013/14), 47 bread winter wheat varieties were phenotypically measured and analyzed with 17 microsatellite loci. 35 marker-trait associations (MTA) for heading date, 39 for plant height, 33 for awn size, 20 for ear colour and 8 for ear size were found to be stable and significant during two–four different gro­wing years. Conclusions. Microsatellite markers that showed substantial and stable during different growing years associations with agronomical traits can be useful and suitable for marker-assisted selection (MAS) in Ukrainian wheat breeding programs.

Purpose. Defining marker-trait associations of microsatellite markers with specific regions of the genome that control important agronomical traits in the investigated varieties originated in the Plant Breeding and Genetics Institute – National Center of Seed and Cultivar Investigations and entered into the State register of plant varieties suitable for dissemination in Ukraine during different years. Methods. Molecular genetic methods (extraction of genomic DNA, polymerase chain reactions (PCR), electrophoresis of amplification products in polyacrylamide gel), field methods (phenological observations of heading date and analysis of plant height, visual assessment of the colour and length of wheat ear and awns), statistical methods (evaluation of trait means by descriptive statistic instruments of EXCEL package, ANOVA method performed by GLM instrument from AGROBASE 21 package). Results. During four gro­wing years (2010/11, 2011/12, 2012/13, 2013/14), 47 bread winter wheat varieties were phenotypically measured and analyzed with 17 microsatellite loci. 35 marker-trait associations (MTA) for heading date, 39 for plant height, 33 for awn size, 20 for ear colour and 8 for ear size were found to be stable and significant during two–four different gro­wing years. Conclusions. Microsatellite markers that showed substantial and stable during different growing years associations with agronomical traits can be useful and suitable for marker-assisted selection (MAS) in Ukrainian wheat breeding programs.

Purpose. To define the role of fertilizers containing amino acids in the nutrition systems of highly productive varieties of winter wheat. Methods. Field studies, biochemical technique, analytical procedure, statistical evalua­tion. Results. In the process of investigations, sufficiently high activity of fertilizers containing amino acids was established when applying them for leaf-feeding. Fertilizers based on algae (Megafol, Megafol Protein, Terra-Sorb foliar) and animal (Izabion) hydrolysates appeared to be very effective for increasing yield of culture. It was found that in case of low doses of mineral nitrogen, fertilizers helped to increase both the yield and quality indicators of high-yielding wheat variety. Conclusions. It was defined that fertilizers that include amino acids are highly effective compositions containing plant-available nitrogen in organic form and can be promising for application as antistress agents and improving efficiency of macro- and microelements use by cultivated plants. They are essential components of modern technologies for cultivation of highly productive varieties and hybrids in crop production of Ukraine.

Purpose. To define the role of fertilizers containing amino acids in the nutrition systems of highly productive varieties of winter wheat. Methods. Field studies, biochemical technique, analytical procedure, statistical evalua­tion. Results. In the process of investigations, sufficiently high activity of fertilizers containing amino acids was established when applying them for leaf-feeding. Fertilizers based on algae (Megafol, Megafol Protein, Terra-Sorb foliar) and animal (Izabion) hydrolysates appeared to be very effective for increasing yield of culture. It was found that in case of low doses of mineral nitrogen, fertilizers helped to increase both the yield and quality indicators of high-yielding wheat variety. Conclusions. It was defined that fertilizers that include amino acids are highly effective compositions containing plant-available nitrogen in organic form and can be promising for application as antistress agents and improving efficiency of macro- and microelements use by cultivated plants. They are essential components of modern technologies for cultivation of highly productive varieties and hybrids in crop production of Ukraine.

Purpose. Providing information on the formation, composition, maintenance of the collection of Buckwheat (Fagopyrum Mill.) genus at Ustymivka Experimental Station of Plant Production (Poltava region), and areas of its use: introduction, preservation and study of the material, for the set of index, formation of special collections and providing research and education institutions of Ukraine with a valuable original material. Methods. Methodical developments dealing with formation and maintenance of crop collections, methodical literature on the study of buckwheat collection for breeding and agronomic performance. Results. The author represented results of the collection material study for the main breeding and economically valuable traits including yield, productivity, resistance to abiotic and biotic factors of the environment. The results of work are considered aimed on creating special collections of the gene pool – base, trait (for yield and large seeds; for productivity, drought and heat resistance; for suitability for mechanical cultivation), educational and core ones. Conclusions. All formed and registered collections are a valuable base material for solving a number of breeding goals to increase the quantity and improve the quality of plant production.

Мета. Суперсолодка кукурудза містить ген, експресія якого зумовлює підвищення концентрації цукру. Ідентифіковано гени ендосперму, що регулюють підвищення вмісту цукру і зменшення вмісту крохмалю; найефективнішими з них були shrunken2 (sh2), brittle1 (bt), sugary1 (su1) і sugary enhancer1 (se). Рецесивна мутація shrunken2 (sh2) забезпечує високий уміст цукрів у зерні молочно-воскової стиглості порівняно з іншими мутантними формами, що безпосередньо впливає на смакові якості sh2-гібридів, обумовлює широке використання цієї мутації в селекційній роботі і має найбільший комерційний потенціал. Основним завданням селекції є створення нового покоління високопродуктивних гібридів, яке залежить від наявності високоякісного вихідного селекційного матеріалу. Тому метою роботи було оцінити лінії суперсолодкої кукурудзи за морфо-біологічними ознаками, виділити ліпші лінії-донори генетичних ознак, створити високопродуктивні гібриди кукурудзи. Методи. Морфо-біологічні ознаки досліджених ліній оцінювали за Класифікатором-довідником виду Zea mays L. Комплексний аналіз зразків за господарсько-цінними ознаками проводили згідно з Методичними рекомендаціями для польового та лабораторного вивчення генетичних ресурсів кукурудзи. Уміст редукувальних цукрів у зерні досліджених ліній і гібридів кукурудзи визначали за методом Бертрана. Результати. Досліджено морфо-біологічні ознаки суперсолодкої кукурудзи. Істотні відмінності між дослідженими лініями спостережено за тривалістю вегетаційного періоду, кількістю насінин в одному ряді й кількістю рядів зерен у качані. Виділено лінії-джерела господарсько-цінних ознак для практичної селекції. Проведено схрещування і отримано 50 гібридних комбінацій, серед яких виділено 16, які характеризувалися кращими показниками господарських ознак. Висновки. У результаті аналізу основних морфо-біологічних ознак у гібридних комбінаціях цукрової кукурудзи з мутантним геном sh2 виділено джерела селекційно-цінних ознак. За тривалістю вегетаційного періоду всі лінії було розділено на три групи: ранні – 8 ліній, середні – 6 і пізні – 8 ліній. Установлено, що перспективними донорами продуктивності качана були лінії SH-621, SH-234 і SH-936, висоти рослин – SH-234 і SH-936, кількості рядів зерен – SH-234 і SH-113, довжини качана – SH-318 і SH-936. За оцінкою морфо-біологічних ознак виділено ліпші лінії, які були схрещені, отримано низку гібридів. Найкращі з них – ‘Матір Драконів F1’, ‘Юрмала F1’ і ‘Ларус F1’ – передано на державну реєстрацію.

Purpose. Reviewing the literature on modern technologies of genetic modification of crop genomes. Results. The current state of genetically modified plants creation is analyzed. The information on cis-, intra- and subgenic plants and their comparison with transgenic crops is given. Examples of cis- and intragenesis application for improving characteristics of crops are provided. Such state-of-the-art technology of crop genome modification as genome editing is considered. Conclusions. Technologies for producing cis-, intra-, subgenic plants are rapidly developing and resulting in crops of the 21st century that can solve the problem of food provision for a constantly growing world population with the least contrary to the public interest.

Purpose. Reviewing the literature on modern technologies of genetic modification of crop genomes. Results. The current state of genetically modified plants creation is analyzed. The information on cis-, intra- and subgenic plants and their comparison with transgenic crops is given. Examples of cis- and intragenesis application for improving characteristics of crops are provided. Such state-of-the-art technology of crop genome modification as genome editing is considered. Conclusions. Technologies for producing cis-, intra-, subgenic plants are rapidly developing and resulting in crops of the 21st century that can solve the problem of food provision for a constantly growing world population with the least contrary to the public interest.

Purpose. Determination of sowing time effect on productivity of various fenugreek species in the Forest-Steppe zone of Ukraine. Methods. Field study, laboratory test, analytical approach and statistical evaluation. Results. Effect of sowing time on economic characters of common fenugreek (Trigonella foenum graecum L.) and blue fenugreek (Trigonella coerulea (Desr.) Ser.) was investigated. It was found that sowing time significantly influenced the individual productivity of plants and average yield of their fresh and dry matter. In particular, common and blue fenugreek plants formed not only the most developed vegetation but also higher productivity and fresh and dry matter yield, respectively, due to early-spring sowing. In case of summer sowing, the poorest yield of dry matter per unit was obtained for these species caused by a low fresh yield, though the moisture loss index was lower. Conclusions. Common fenugreek is promising for producing “mushroom grass” spices, and the conveyor supply of production in the Forest-Steep zone of Ukraine can be ensured by the first sowing time (the first or the second decades of April) and the se­cond sowing time (the third decade of April) as during this period more developed vegetation is formed that favored the higher yield of dry matter (1,3–1,5 t/ha).

Purpose. To evaluate pea plants productivity and determine the degree of correlation among the main agronomic characters in pea varieties. Methods. Structural and statistical analysis. Results. Evaluation of pea samples in terms of indices of plant productivity elements level based on correlation analysis and single-factor indices appliance provided insight into the ratio of one trait share per unit of another one. It was defined that some correlations among the elements of productivity was not only moderate and weak, but they also changed their sign that could be the evidence of growth conditions influence on structural relationships bet­ween some traits and, consequently, redistribution of their contributions to the formation of variety productivity. Positive and very close relationship of many traits was revealed, particularly between plant height and the height of the plant up to the first bean, the number of nodes and the number of sterile nodes (r = 0,95–0,97). Methodological aspects of the variety model creation were considered, that may be useful not only in pea breeding but also for improving the techno­logy of its cultivation. Conclusions. Correlation relationships were established between the number of beans and the number of fruiting nodes and the number of carpophores containing 2 beans (r = 0,86–0,88), seed mass and plant mass (r = 0,81), the number of seeds per plant and plant mass and seed mass per plant (r = 0,78–0,81), the number of certified seeds and the number of seeds per plant (r = 0,84), the average number of beans per fertile node and the number of carpophores containing 2 beans (r = 0,74) that makes it possible to use them in assessing the productivity of plants.

Purpose. The analysis of allelic status of such key genes of carotenogenesis as gene of lycopene-ε-cyclase (lcyε) and gene of β-carotene hydroxylase (crtRB1) for DNA-markers in domestic maize lines and their hybrids. Methods. DNA isolation, PCR, gel electrophoresis. Results. Allelic status of key genes of carotenogenesis was investigated in eight maize inbred lines and their single crosses. Molecular genetic polymorphism in the studied sample of maize lines and hyb­rids has been detected in gene of β-carotene hydroxylase for marker crtRB1-3’TE. For this gene, codominant character of inheritance of alleles of parental lines in single crosses was confirmed. For markers of gene of lycopene-ε-cyclase lcyε-3’INDL and lcyε-SNP216, polymorphism in the group of investigated lines and hybrids has not been identified, genotypes included only one variant of alleles for each marker. For lines ‘DK253ZSZM’, ‘DK633/266zS,zM’, ‘DK366zS,zM’ and hybrids ‘DK296S×DK253ZSZM’, ‘DK272S×DK633/266zS,zM’ and ‘DK231S×DK366zS,zM’, the decrease of the activi­ty of β-carotene hydroxylase owing to the mutation of gene crtRB1 under the influence of transposone element at the 3’-end, the inhibition of β-carotene transition into β-cryptoxanthin can be expected, that allows to predict β-carotene accumulation in grain. Conclusions. The study of allelic status of carotenegenesis gene of lycopene-ε-cyclase in maize showed no polymorphism for markers lcyε-3’INDL and lcyε-SNP216 in eight inbred lines and their single crosses, along with this, for marker lcyε-3’INDL in genomes of all studied samples the allele was identified to be favorable for the accumulation of β-carotene. For marker crtRB1-3’TE of gene of β-carotene hydroxylase, the studied breeding material was polymorphic. Allele of crtRB1 being favorable for the accumulation of β-carotene was identified in lines ‘DK253ZSZM’, ‘DK633/266zS,zM’, ‘DK366zS,zM’ and hybrids ‘DK296S×DK253ZSZM’, ‘DK272S×DK633/266zS,zM’ and ‘DK231S×DK366zS,zM’. Single crosses inherit maternal and paternal alleles of gene of β-carotene hydroxylase codominantly.

Purpose. The analysis of allelic status of such key genes of carotenogenesis as gene of lycopene-ε-cyclase (lcyε) and gene of β-carotene hydroxylase (crtRB1) for DNA-markers in domestic maize lines and their hybrids. Methods. DNA isolation, PCR, gel electrophoresis. Results. Allelic status of key genes of carotenogenesis was investigated in eight maize inbred lines and their single crosses. Molecular genetic polymorphism in the studied sample of maize lines and hyb­rids has been detected in gene of β-carotene hydroxylase for marker crtRB1-3’TE. For this gene, codominant character of inheritance of alleles of parental lines in single crosses was confirmed. For markers of gene of lycopene-ε-cyclase lcyε-3’INDL and lcyε-SNP216, polymorphism in the group of investigated lines and hybrids has not been identified, genotypes included only one variant of alleles for each marker. For lines ‘DK253ZSZM’, ‘DK633/266zS,zM’, ‘DK366zS,zM’ and hybrids ‘DK296S×DK253ZSZM’, ‘DK272S×DK633/266zS,zM’ and ‘DK231S×DK366zS,zM’, the decrease of the activi­ty of β-carotene hydroxylase owing to the mutation of gene crtRB1 under the influence of transposone element at the 3’-end, the inhibition of β-carotene transition into β-cryptoxanthin can be expected, that allows to predict β-carotene accumulation in grain. Conclusions. The study of allelic status of carotenegenesis gene of lycopene-ε-cyclase in maize showed no polymorphism for markers lcyε-3’INDL and lcyε-SNP216 in eight inbred lines and their single crosses, along with this, for marker lcyε-3’INDL in genomes of all studied samples the allele was identified to be favorable for the accumulation of β-carotene. For marker crtRB1-3’TE of gene of β-carotene hydroxylase, the studied breeding material was polymorphic. Allele of crtRB1 being favorable for the accumulation of β-carotene was identified in lines ‘DK253ZSZM’, ‘DK633/266zS,zM’, ‘DK366zS,zM’ and hybrids ‘DK296S×DK253ZSZM’, ‘DK272S×DK633/266zS,zM’ and ‘DK231S×DK366zS,zM’. Single crosses inherit maternal and paternal alleles of gene of β-carotene hydroxylase codominantly.

Purpose. To establish adaptive capacity and reproduction time of the registered potato varieties elite bred at the Potato Research Institute of NAAS of Ukraine in various edaphic and climatic zones of Ukraine. Methods. Field and laboratory tests, statistical evaluation. Results. Potato varieties were tested in the Forest-Seppe, Polissia and Steppe zones of Ukraine. Over the years of testing (2012–2014), the highest yield of potatoes in the south-western part of the Forest-Steppe zone was produced by the early varieties: ‘Kimmeria’ – 46.9 t/ha, ‘Vedruska’ – 38.6 t/ha; middle-early varieties: ‘Partner’ – 33.2 t/ha, ‘Fantazia – 27.7 t/ha; mid-season varie­ties: ‘Okolytsia’ – 35.4 t/ha, ‘Mandrivnytsia’ – 25.1 t/ha. In the Central Polissia, ‘Kimmeria’ (31 t/ha) was the most productive early variety, the yield at the level of 27.6–29.2 t/ha was formed by such varieties as ‘Skarbnytsia’, ‘Serpanok’, ‘Radynka’, ‘Tyras’. Among the middle-early varieties, the yield of 33.1 t/ha was obtained from the variety ‘Partner’. In the conditions of Steppe zone, such early potato varieties as ‘Vymir’, ‘Glazurna’, ‘Strumok’, ‘Kimmeria’, ‘Svitoch’ and the middle-early variety ‘Ariya’ had the highest productivity in case of gro­wing as bivoltine crop under irrigated conditions. It was found that in the Forest-Steppe and Polissia zones such varieties as ‘Kimmeria’, ‘Vedruska, ‘Serpanok’, ‘Skarbnytsia, ‘Tyras’, ‘Radynka’, ‘Partner’, ‘Slovianka’, ‘Vernisazh’, ‘Mandrivnytsia’, ‘Poliske dzherelo’ and ‘Chervona ruta’ were characterized by high resistance to degeneration (viral diseases and loss of productivity of potato elite in the process of reproduction). According to the results of evaluation of the impact of elite potato reproduction time on affection by viral diseases, optimal time for elite renovation for investigated varieties was determined. Conclusions. In the process of testing in various edaphic and climatic zones of Ukraine, stable yield with a high seed tubers number, regardless of weather conditions during the growing season in the Forest-Steppe and Polissia zones, was formed by some early potato varieties (‘Kimmeria’, ‘Vedruska’, ‘Radynka) and middle-early one (‘Partner’). Among mid-season varieties ‘Vernisazh’, ‘Okolytsia’, ‘Mandrivnytsia’ were identified for high productivity, and among middle-late – ‘Poliske dzherelo’ and ‘Chervona ruta’. The most common viral diseases of potatoes were rugose mosaic and mosaic leaf curling. High efficiency of the use of bivoltine crop method for potato growing to obtain seed material in the Southern Steppe zone of Ukraine has been proved.

Purpose. To establish adaptive capacity and reproduction time of the registered potato varieties elite bred at the Potato Research Institute of NAAS of Ukraine in various edaphic and climatic zones of Ukraine. Methods. Field and laboratory tests, statistical evaluation. Results. Potato varieties were tested in the Forest-Seppe, Polissia and Steppe zones of Ukraine. Over the years of testing (2012–2014), the highest yield of potatoes in the south-western part of the Forest-Steppe zone was produced by the early varieties: ‘Kimmeria’ – 46.9 t/ha, ‘Vedruska’ – 38.6 t/ha; middle-early varieties: ‘Partner’ – 33.2 t/ha, ‘Fantazia – 27.7 t/ha; mid-season varie­ties: ‘Okolytsia’ – 35.4 t/ha, ‘Mandrivnytsia’ – 25.1 t/ha. In the Central Polissia, ‘Kimmeria’ (31 t/ha) was the most productive early variety, the yield at the level of 27.6–29.2 t/ha was formed by such varieties as ‘Skarbnytsia’, ‘Serpanok’, ‘Radynka’, ‘Tyras’. Among the middle-early varieties, the yield of 33.1 t/ha was obtained from the variety ‘Partner’. In the conditions of Steppe zone, such early potato varieties as ‘Vymir’, ‘Glazurna’, ‘Strumok’, ‘Kimmeria’, ‘Svitoch’ and the middle-early variety ‘Ariya’ had the highest productivity in case of gro­wing as bivoltine crop under irrigated conditions. It was found that in the Forest-Steppe and Polissia zones such varieties as ‘Kimmeria’, ‘Vedruska, ‘Serpanok’, ‘Skarbnytsia, ‘Tyras’, ‘Radynka’, ‘Partner’, ‘Slovianka’, ‘Vernisazh’, ‘Mandrivnytsia’, ‘Poliske dzherelo’ and ‘Chervona ruta’ were characterized by high resistance to degeneration (viral diseases and loss of productivity of potato elite in the process of reproduction). According to the results of evaluation of the impact of elite potato reproduction time on affection by viral diseases, optimal time for elite renovation for investigated varieties was determined. Conclusions. In the process of testing in various edaphic and climatic zones of Ukraine, stable yield with a high seed tubers number, regardless of weather conditions during the growing season in the Forest-Steppe and Polissia zones, was formed by some early potato varieties (‘Kimmeria’, ‘Vedruska’, ‘Radynka) and middle-early one (‘Partner’). Among mid-season varieties ‘Vernisazh’, ‘Okolytsia’, ‘Mandrivnytsia’ were identified for high productivity, and among middle-late – ‘Poliske dzherelo’ and ‘Chervona ruta’. The most common viral diseases of potatoes were rugose mosaic and mosaic leaf curling. High efficiency of the use of bivoltine crop method for potato growing to obtain seed material in the Southern Steppe zone of Ukraine has been proved.