Enhanced wheat (Triticum aestivum) performance: effects of PGPR-enriched on yield and biochemical profiles

Plant growth-promoting rhizobacteria (PGPR) are increasingly applied in sustainable agriculture to enhance plant growth, improve yield, and induce tolerance to stress condition while reducing chemical inputs. Tuff, a porous volcanic material with high water-holding and cation exchange capacity, was used as a carrier to inoculate and deliver PGPR to the plant root zone. This two-year greenhouse study evaluated the effects of PGPR-inoculated tuff (T1) compared with non-inoculated tuff (T0, control) on the growth, physiological performance, antioxidant enzyme activities, and biochemical profiles of 'K & imath;rik' wheat. Large tuff (9 & times; 14 & times; 11 mm) were inoculated with approximately 4.8 & times; 1010 cfu/g PGPR and applied to the root zone of each plant. PGPR application increased grain yield by 20.43% and significantly improved chlorophyll content, stomatal conductance, membrane permeability, and photosynthetic rate. Antioxidant enzymes, including CAT, SOD, and POD, showed increases of 11.43, 14.83, and 10.71%, respectively. Levels of IAA (13.59%), GA (7%), and SA (9.27%) were elevated, whereas ABA decreased by 16.67%. Amino acid and organic acid contents were generally enhanced, along with significant increases in nutrient element concentrations, most notably P (18.49%), Cu (10.61%), and Fe (9.99%); in contrast, Na and B concentrations decreased by 5 and 3.48%, respectively. These findings indicate that PGPR-inoculated tuff can improve nutrient availability and growth and physiological performance in wheat, offering a low-cost, scalable biological input to complement conventional fertilization in sustainable wheat production. Further field studies comparing this approach with standard chemical fertilization are needed to confirm its practical applicability and support broader adoption.