Filters
Effect of Biostimulants Containing Rhizobacteria on the Growth of Wheat, Barley, and Oilseed Rape Under Various Soil Moisture Conditions
Preparations containing appropriate microorganisms stimulate plant growth and are increasingly used to alleviate plant stress, including water deficit stress. Despite the growing interest in PGPR, little is known about the post-emergence efficacy of formulations based on native strains under water stress. In this study, we tested the post-emergence efficacy of preparations based on Bacillus velezensis_KT27 and Bacillus subtilis + Pseudomonas simiae + Bacillus velezensis_S103 at doses of half a liter and one liter × 200 L × ha−1 in culture fluid or oil dispersion each at a final microbial cell concentration of 5 × 108 (CFU/mL) for the tested strains. Our hypothesis was that the different biostimulants may positively affect plants’ tolerance to water stress. To this end, analyses of plant height, fresh weight, dry weight, chlorophyll, flavonol and anthocyanin content, and chlorophyll fluorescence were conducted under greenhouse conditions for winter wheat, winter barley, and winter oilseed rape. The preparations promoted the growth and water-stress tolerance of the selected plants, with effectiveness depending on strain, plant, dose, and formulation. B. velezensis_KT27 (0.5 L in oil dispersion) increased the dry weight of winter wheat by 17% (optimal) and 14% (water deficit stress) and of winter barley by 17% and 28%. Bacillus spp. + Pseudomonas spp. (0.5 L in oil dispersion) increased winter oilseed rape dry weight by 13% in both conditions. These findings highlight the potential of Bacillus spp. and Pseudomonas spp. for post-emergence biostimulation under variable soil levels of moisture.
Projekty Katedry Biotechnologii i Mikrobiologii Żywności realizowane w ramach finansowania z Inkubatora Innowacyjności CIITT
Konsorcjum bakteryjno-grzybowe i sposób bioremediacji gleby skażonej substancjami ropopochodnymi
Sposób usuwania zanieczyszczeń ropopochodnych z gleby na drodze biodegradacji przy użyciu kwasów humusowych i hydrolizatu drożdżowego
Moisture governs diesel biodegradation in sand soil – polystyrene microplastic have a negligible impact
Critical evaluation of the performance of rhamnolipids as surfactants for (phyto)extraction of Cd, Cu, Fe, Pb and Zn from copper smelter-affected soil
Biocontrol of Cercospora leaf spot in sugar beet by a novel Bacillus velezensis KT27 strain: Enhanced antifungal activity and growth promotion in laboratory and field conditions
Diseases in crops are a major contributor to yield reduction and economic losses. Cercospora leaf spot (CLS), caused by Cercospora beticola, is among the most severe diseases affecting sugar beet and other crops. The increasing resistance of C. beticola to conventional chemical fungicides, along with their excessive application, exacerbates environmental pollution. This study investigates the antagonistic activity of a newly isolated strain, Bacillus velezensis KT27, against Cercospora beticola, Rhizoctonia cerealis, and Fusarium oxysporum under laboratory conditions. The bacterium’s ability to produce lipopeptides (surfactin, iturin, and fengycin) and solubilize phosphorus, potassium, and zinc was also assessed. In vitro assays revealed that B. velezensis KT27 effectively inhibited C. beticola growth (60.2%), though it exhibited lower antagonistic activity against R. cerealis (22.5%) and F. oxysporum (15.5%). The elimination of bacterial biomass by centrifugation and the use of sterile supernatant reduced antifungal activity by more than 3.5-fold for all tested fungi, highlighting the importance of direct bacterial interactions. Notably, the antagonistic effect of B. velezensis KT27 against C. beticola significantly increased when bacterial cultures were supplemented with thermally inactivated fungal biomass of C. beticola especially R. cerealis. Field experiments demonstrated the high efficacy of B. velezensis KT27 biological control agent, particularly when induced by R. cerealis. The level of CLS protection achieved with the bacterial treatment was only 9.1% lower than that obtained using a combination of three chemical fungicides. Additionally, the biocontrol agent positively influenced sugar beet growth, leading to a root yield increase of up to 15.2% compared to the untreated control. These findings highlight the potential of B. velezensis KT27 as an effective and environmentally sustainable biocontrol agent against CLS in sugar beet cultivation.