Purpose. To determine the genetic effects of WRT 1AL.1RS and 1BL.1RS on the yield, plant productivity elements and quality indices of recombinant lines, to determine the effectiveness of using each of the WRT for creating more perfect varieties of soft winter wheat in these traits under soil-air drought in the steppe zone of Ukraine and development of breeding techniques to reduce the negative effects of translocation to produce genotypes with high quality indices of valuable and strong wheat grain. Methods. Field experiments, intraspecific hybridization, evaluation of breeding material in the field, methods of laboratory determination of baking quality indices of grain, electrophoresis of spare proteins, statistical. Results. Under arid conditions of the South of Ukraine on the large experimental material of breeding process, a positive effect of 1AL.1RS on the yield of recombinant lines and the main elements of plant productivity were determined, which was manifested against the background of simultaneous positive effect of this transposition on the drought and heat tolerance. The use of 1BL.1RS in wheat breeding in this region is less promising technique. It has been determined that introduction of 1AL.1RS, 1BL.1RS translocations into local gene pool of soft winter wheat by hybridization changes the grain quality indices. In particular, the protein content tends to increase more significantly under the influence of 1BL.1RS translocation. It has been shown that the frequency of obtaining recombinant lines which combine high yield and sufficient level of baking properties (not lower than valuable and strong wheat) is quite low (1,7–6,1%), but introgressive lines with 1AL.1RS have the advantages in this parameter. Using such genetic factors as hybridization combining WRT with alleles with high positive effect on baking properties, and also creating heterogeneity in the composition of genotypes with and without WRT, one can purposefully reduce the negative impact of WRT on the quality of soft winter wheat grain and create varieties with quality parameters of valuable and strong wheat. Conclusions. In general, the results achieved give reason to assert that the use of WRT 1AL.1RS is a promising direction for further breeding increase of genetic capacity of soft winter wheat varieties in the arid conditions of the South of Ukraine. As a result of full cycle of breeding process on the material with 1AL.1RS WRT a series of varieties of soft winter wheat ‘Zhytnytsia odeska’, ‘Oktava odeska’, ‘Liha odeska’, ‘Duma odeska’, ‘Versiia odeska’, providing 10 – 15% increase in yield to standards was created and included in the State Register of Ukraine and Moldova.

Purpose. To determine the growing factors impact the economically valuable characteristics of new soft winter wheat varieties. Methods. Field, biochemical methods, ANOVA. Results. The influence of the growing zone, the growing season conditions and the genotype of the soft winter wheat varieties on yield, protein and gluten content were determined. The conditions of the growing zone have the greatest influence on studied varieties yield – 73%. On average, for 2020–2021, the maximum yield was obtained in the Forest-Steppe zone – 6.23–8.39 t/ha. In the Forest zone, the yield of studied soft winter wheat varieties was 5.31–7.02 t/ha. For the Steppe zone, the yield was within 5.16–6.63 t/ha. It was determined that varieties which showed low yield in the Forrest zone were characterized by higher yield in the Steppe zone. It was found that the growing zone (49%) and growing season (42%) conditions have the greatest effect on the protein content in grain of studied varieties. It was determined that variety ‘MANDARIN’ was characterized by the highest protein content in all growing zones (14.5–16.4%). In the Steppe and Forest-Steppe zones, high protein content was identified in grain of wheat varieties ‘Tata Mata’ (13.6–14.3%), ‘Eneida’ (13.6–14.3%) and ‘Novator’ (14.2 and 13.2%), in the Forest zone – in grain of varieties ‘Vahoma’ and ‘Eneida’ – 13.4% each. It was found that the growing zone conditions impacted gluten content in grain of studied wheat varieties by 64%, the influence of the growing season conditions was 28%. The effect of variety genotype on protein and gluten content was 5 and 4%, respectively. The grain of soft winter wheat varieties ‘MANDARIN’ and ‘Eneida’ contained the largest amount of gluten in all growing zones (27.7–31.8% and 27.3–30.3%). For the Steppe and Forest-Steppe zones, a high gluten content was found in grains of varieties ‘Illusion’ (28.4 and 30.8%) and ‘Tata Mata’ (27.8 and 29.8%). Conclusions. It was found that growing zone conditions of soft winter wheat varieties (73%) and the interaction of factors zone × year (21%) impacted the yield significantly. The growing zone conditions (49 and 64%), growing season conditions (21 and 28%) and genotype of variety (5 and 4%, respectively) had a significant influence on protein and gluten content. Therefore, a significant influence of growing zone conditions on the productivity indicators of soft winter wheat determines the need to select varieties in order to obtain a high yield, taking into account the soil and climatic zone