The paper presents the results of studying biological methods of increasing the yield of planting material for grapes and increasing the germination of hybrid seeds to accelerate the selection process. The impact of bioactive compounds (6-benzylaminopurine and gibberellic acid) in culture medium on production of grape clones during micropropagation stage was studied. Modified culture medium of the A.N. Rebrov’s patent was determined as having the most potential on the first stage of grape explant cultivation. The establishment of grape regenerant plants was up to 80%, depending on the variety. On the second and third passages Rebrov’s culture medium was modified by the addition of 6-benzylaminopurine in the concentration 0.35 mg/l and gibberellic acid in the concentration 0.1 mg/l. The method of prestratification soaking of seedlings seeds in the solutions of gibberellic acid of various concentrations was also studied to accelerate the breeding process. The production of seedlings increased to 91.2% at the concentration of gibberellic acid 0.01% that was higher than control production on 31.2%.

In 2019-2020, experiments were laid on the fields of the ARRIV&W – Branch of FRARC with the aim of experimentally determining the phenotypic signs of compatibility of scion-rootstock combinations with the participation of grape varieties of interspecific origin Denisovskiy and Prestige and rootstock varieties Kober 5 BB and Riparia Rupestris 101-14 introduced to the State Register of Breeding Achievements of the Russian Federation, approved for use. According to the results of the studies, it can be concluded that the selection of the optimal scion-rootstock for growing the necessary scion varieties has a direct effect on the yield of seedlings, which, with the same level of agricultural technology, will minimize production costs for inoculating seedlings and repairing grape plantations. The influence of the rootstock variety on the phenotypic characteristics of the scion variety has been established. The yield of seedlings is the most objective indicator of the compatibility of the scion-rootstock combination. According to the research results 2019-2020. it was found that the yield of first-class seedlings of the Denisovsky and Prestige varieties significantly depends on the used rootstock variety. The Riparia Rupestris 101-14 rootstock has the highest yield of seedlings of the Denisovskiy variety, 45.4%, which is 21.6% more than on the Kober 5 BB rootstock variety. On the Denisovskiy variety, the seedling yield was 48.0%, which is 39.9% more than on the Kober 5 BB rootstock variety.

The article reflects the results of studies carried out in the period from 2017 to 2019 in the dry steppe zone of the Russian Federation to assess the resistance of sunflower and the effectiveness of weed control when using oxyfluorfen before sowing and during the growing season of the crop in various doses and tank mixtures. The dynamics of weediness of sunflower crops according to the growing season of the crop and the timing of the use of herbicides and their tank mixtures has been established. The data of accounting for the increase in leaf area, as well as determining the photosynthetic potential of crops and the net productivity of photosynthesis when using herbicides before sowing and during the growing season of sunflower in different doses and tank mixtures are presented. Indicators of sunflower productivity and quality of seeds were determined for the studied schemes of herbicide application. The data obtained from the economic and energy assessment of the effectiveness of the use of oxyfluorfen on sunflower in terms of crop vegetation are analyzed.

The grafted grape culture is highly demanded in industrial production due to a number of advantages in comparison with its own rooted culture. The high cost of production of grafted seedlings and climate change necessitate a change in the planting depth of grape plantations for the Rostov region by reducing the length of the rootstock and the selection of optimal scion-rootstock combinations. In this regard, in 2019-2020, I was on the experimental field of the ARRIV&W – Branch of FRARC, an experiment was laid in order to study the effect of length (from 30 to 45 cm) and varieties (Kober 5BB and Riparia Rupestris 101-14) stock on agro biological indicators of grafted grape seedlings of the Denisovskiy variety. According to the research results, it was found that, depending on the length of the rootstock, with a length of 30 cm, there is an increase in the yield of grafts from the chamber to 82.65%, the survival rate to 82.5% and the final yield of seedlings to 52.4 cm. The greatest influence on the quality of seedlings was rootstock variety. The stock-rootstock combination Denisovskiy × Kober 5 BB has a low seedling yield from 15.5 to 24.6%, which is lower than the Denisovskiy × Riparia Rupestris 101-14 combination with a seedling yield from 36.4 to 52.4%. It can be concluded that, according to the results of the experiment, a positive dependence was revealed in the yield of grafted seedlings of the Denisovskiy variety with a rootstock Riparia Rupestris 101-14 and a rootstock length of 30 cm, in comparison with the widespread rootstock variety Kober 5 BB and a length of 45 cm.

No abstract