Role of inoculation with multi-trait rhizobacteria on strawberries under water deficit stress

This study was conducted during 2011 and 2012 to evaluate the effect of 1-aminocyclopropane-1-carboxylate (ACC) deaminase-containing, N-2-fixing and P-solubilizing bacteria on the yield and morpho-physiological parameters of strawberry. A total of 8 applications at the trial set, with four water regimes were randomly distributed into the pots. The diminishing water supply caused a gradual decrease in the plant growth, chlorophyll content and berry yield, accompanied by increasing activities of drought stress markers such as total phenolics content (TPC), trolox equivalent antioxidant capacity (TEAC), malondialdehyde (MDA) content, hydrogen peroxide (H2O2), glutathione reductase (GR), glutathione S-transferase (GST), catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) and ascorbate peroxidase (APX) in the leaves of strawberry. The multi-trait bacteria also increased plant growth and yield as well as TPC, TEAC, antioxidant enzymes (GR, GST, CAT, POD, SOD and APX) activity, phytohormone (GA, SA and IAA) and the contents of N, P, K, Ca, Fe, Mn, Zn and Cu, but decreased MDA and H2O2 contents which may contribute in part to activation of physiological and biochemical processes involved in the alleviation of the effect of drought stress.