Northeastern Forest-Steppe Of Ukraine Research Articles

Effects of testing conditions of complex interspecies potato hybrids, their backrosses on the average weight of commercial tubers

Purpose and objectives. To determine the potential of complex interspecies potato hybrids, their backcrosses in terms of the average weight of commercial tubers and to identify the effects of exrenal conditions on the trait expression.Materials and methods. The study was conducted in two soil-climatic zones: the northeastern forest-steppe of Ukraine (Sumy National Agrarian University) and southern woodlands of Ukraine (Institute of Potato Growing) in 2015–2017. We studied the influence of external conditions on the average weight of commercial tubers in 34 complex interspecies hybrids and their backcrosses. The technique was common in experiments on potato.Result and discussion. A high potential of the material under investigation was recorded for the average weight of commercial tubers with the maximum expression of the indicator in a double backcross of four-species hybrid 00.72 /5 in SNAU in 2017 –217 g.We experimentally proved the influence of the external conditions: the study locations and meteorological conditions during the growing period on the trait expression. Hybrids with the average weight of commercial tubers of >100 gin the SNAU conditions were the most frequent in 2017 (23.5%) and the least frequent in 2015 and 2016 (4.9% and 3.9%, respectively). In the IPG, there were no such hybrids in 2015 or 2017; their percentage only was 1.0% in 2016.The high potential of the material under investigation in terms of the trait expression is confirmed by occurrence of hybrids with an increased level of the indicator than that in the best standard variety, which was observed regardless of the external conditions.The best conditions for the formation of commercial tubers with the maximum weight were in SNAU in 2017; their percentage was 27.5% of their total number. Close, albeit lower, percentages were achieved in the IPG in 2016 and 2017: 15.7 and 13.7%, respectively.We observed significant effects impact of the external conditions during the potato growing period on the indicator expression. In SNAU trials, most of the hybrids had the variation coefficients within 21-30% and 31-40%, and in the IPG conditions they were £ 10% or 11-20%. The above-said was also confirmed by categorization of the hybrids, depending on the experiment location and the conditions during the growing period. In SNAU, 2017 was the most favorable for the trait expression. The opposite was true for2015. Inthe IPG, the best distribution of the material by the high average weight of one commercial tuber was noted in 2016 and the worst - in 2015.We revealed different relationships between the genetic control of the trait and the external conditions in sibling forms, which was manifested as various expression of the indicator depending on the trial location and the meteorological conditions in the trial years.Conclusions. The influence of the conditions in the study location and the meteorological conditions during the growing period on the expression of the average weight of commercial tubers was demonstrated. They affected the fulfillment of the genetic potential of the accessions under investigation, its maximum manifestation, the variation coefficients, and categorization of the hybrids into classes of the indicator values.

Evaluation of CIMMYT’s Triticum aestivum L. accessions from the 4th WWSRRN for resistance to powdery mildew in the north-eastern forest steppe of Ukraine

Aim. To determine immunological characteristics of CIMMYT’s accessions from the 4th WWSRRN for resistance to powdery mildew in the north-eastern forest-steppe of Ukraine and to select resources of resistance of the train of interest. Results and Discussion. Thirty five CIMMYT’s accessions from the 4th WWSRRN were taken as the test material. Resistance of wheat plants to powdery mildew was assessed on natural infectious background using varieties - infection accumulators (Keprok, Agassis) in compliance with conventional. To determine the yield capacity of the varieties, we analyzed the plant morphology in harvested sheaves. We measured the plant height and 1000-seed weight. The data were statistically processed. We found that the variability of resistance to powdery mildew in the 4th WWSRRN accessions significantly depended on the genotype – 44 %. In a three-year study, we discovered that the highest resistance was intrinsic to the middle-late group (7.3 points), and the lowest one – to the mid-ripening group (6.3 points), though these accessions had the highest adaptability because the variability was 0.8 points. We compared accessions belonging to various ripeness groups. The middle-late group contained the highest percentage of highly resistant genotypes – 83 %. The test accessions were compared with check variety Podolianka for resistance to powdery mildew. Thirteen accessions significantly exceeding the check variety were identified. We distinguished accession Fiorina with high resistance (8.1 points) to the pathogen. Having examined the averages for the 4 ripeness groups, we can state that the highest yields were produced by accessions from the mid-early and mid-ripening groups - 588 g/m2. Therefore, these groups of varieties have the best adaptability. Conclusions. The comprehensive study of the CIMMYT’s accessions from the 4th WWSRRN on natural infectious background using varieties - infection accumulators allowed us to single out accessions with high resistance to the powdery mildew pathogen and other economically valuable characteristics: Cv. Rodina/AE. Speltoides (10 KR), Vorona / HD2402 // Steklovidnaya 24, ETA / K-62905=ESTER, Cv. Rodina / Aе. Speltoides (10 KR). They can be recommended as sources of resistance to the pathogen, high adaptability and performance for programmes developing new breeding material of winter wheat.

Effect of weather and climate parameters on the crop productivity of modern soybean varieties in the north-eastern Forest steppe of Ukraine

Effect of weather and climate parameters on the crop productivity of modern soybean varieties in the north-eastern Forest steppe of Ukraine

Врожайність цибулі озимої за вирощування із сіянки за різних строків садіння та систем удобрення

The publication presents the results of studies to determine the effectiveness of planting dates and fertilizer systems when growing onions in winter crops in rainfed conditions in the northeastern forest-steppe of Ukraine. The optimal time to seed for the Tkachenkivska and Mayak varieties is the third decade of August, for the Wolf F1 hybrid - the second decade of September. The optimal plant nutrition system is the application of N 82 P 75 K 110 . In these conditions, the largest bulbs are formed, an increase in the winter hardiness of plants is observed, which ensures the highest commodity yield.