Phytostimulatory effect of bacterial strains on oiled flax and black cumin cultivation

In order to examine the influence of plant growth stimulating bacteria, which belong to the genus Streptomices sp., Paenibacillus sp. and Hymenibacter sp., on the yield and seed quality of linseed and black cumin, as well as on the morphological characteristics of these plants, a two-year field experiments were conducted. Soil treatment with a mixed culture of bacteria of different concentrations was applied during the sowing of plants. Before sowing, the influence of individual strains on the germination index of linseed and black cumin was examined. Based on the results presented in the paper, the strains CKS1 - Paenybacillus chitinolyticus, CKS3 - Hymenobacter sp., and CKS7 - Streptomyces fulvissimus, gave germination index values GI over 100% in linseed, within all tested concentrations, while in black cumin, such an effect was shown only by strain CKS7. The positive effect of the bacterial preparation in both examined plant species was recorded by measuring the yield of seeds per hectare treated with a lower concentration of the bacterial preparation compared to the corresponding untreated samples (control sample). A significant difference was recorded by measuring the number of cocoons in samples of treated linseed compared to untreated ones, as well as the mass of roots of both treated plant species. Also, the highest overall germination compared to the control was achieved by the linseed variant L2 in the treatment with a lower concentration of bacteria of 98.3±1.4%.