Zeki Kara

Growth and mineral acquisition response of grapevine rootstocks (Vitis spp.) to inoculation with different strains of plant growth‐promoting rhizobacteria (PGPR)

BACKGROUND Effects of the plant growth-promoting rhizobacteria (PGPR) strains Burkholderia gladii BA-7, Bacillus subtilis OSU-142, Bacillus megatorium M-3 and Azospirillum brasilense Sp 245 on vegetative development and mineral uptake of 1103 P and 41 B grapevine rootstocks were investigated. The roots of nursery plants of the grapevine rootstocks were immersed in bacterial solutions and transplanted to a sterilised peat and perlite mixture in 5 L pots. Plants were cultivated in a semi-controlled glasshouse during the vegetation period. RESULTS Vegetative development of grapevine rootstocks was obviously promoted by bacterial inoculation, with the maximum increase induced by Sp 245. Inoculation with Sp 245 also significantly improved the chlorophyll concentrations of the leaves of the two rootstocks. Among the bacteria, OSU-142 also significantly stimulated vegetative development and mineral acquisition of the plants. Nutrient contents of the leaf blades of the plants were generally higher than those of control plants. CONCLUSION Overall investigations revealed that A. brasilense Sp 245 and B. subtilis OSU-142 performed more efficiently than the other strains. Therefore these bacteria seem to have considerable potential in reducing the need for inorganic fertiliser.