Effects of Pseudomonas strains and microbiological preparations based on Bacillus bacteria on black currant productivity

In 2024–2025, a series of greenhouse experiments were conducted to investigate the effects of Pseudomonas bacterial strains and Bacillus -based microbiological preparations on the generative and vegetative productivity of Mif and Barmaley blackcurrant ( Ribes nigrum L.) cultivars. The generative productivity of Barmaley plants, compared to Mif plants, increased under the action of the microbiological strains and preparations under study, with the exception for Fitosporin-M. Bacillus -based microbiological preparations, as well as Pseudomonas strains, reduced the generative productivity of the Mif cultivar compared to the fertilized treatment. In comparison with Mif, Barmaley plants showed a positive response to the application of microbiological preparations and bacterial strains in terms of generative productivity. The highest generative productivity of Barmaley was recorded in the variant “Background + Alirin-B” in the amount of 334.3 g per plant. The application of the P. putida O9-10 strain contributed to an increase in berry mass per plant up to 303.5 g, which exceeded the control by 61.7 %. For the Mif cultivar, the total length of the current year’s growth was greatest in the “Background + P. chlororaphis BS1393” variant (54.4 % higher than in the control), while for Barmaley, it was greatest in the standard treatment with mineral fertilizers. The use of bacterial preparations based on Bacillus bacteria and Pseudomonas strains resulted in a decrease in vegetative productivity in the Barmaley cultivar compared to the treatment with mineral fertilizers. The opposite pattern was observed for the Mif cultivar.