Effect of Bacterial Inoculation on Morphological and Pomological Characteristics of Three Strawberry (Fragaria x ananassa Duch.) Cultivars Under Cadmium Toxicity

Abstract

Cadmium (Cd) is one of the main elements that cause heavy metal pollution, which is one of the important types of environmental pollution. There is a constant quest to reduce or eliminate the effects of Cd pollution. Plant growth-promoting rhizobacteria (PGPR) is one of these possible solutions. PGPRs not only increase plant growth but also protect plants against organic and inorganic stresses. In this study, the effects of three different Pseudomonas strains (MS-7, MS-12, and MS-13) on morphological and pomological characteristics of three different strawberry cultivars (Rubygem, Kabarla, and YFL) exposed to three different Cd doses (0, 100 and 300 mg kg-1) were investigated to determine the effectiveness of PGPR against Cd toxicity in strawberry. To this end, root collar diameter (RCD), root length (RL), root fresh weight (RFW), root dry weight (RDW), shot fresh weight (SFW), shot dry weight (SDW), leaf area (LA), mean fruit weight (MFW), mean fruit length (MFL), and mean fruit diameter (MFD) were examined. It was observed that the effects of different Pseudomonas strains were cultivar-specific and affected some parameters more. Rubygem MS-7 bacterial strain preserved SDW (3.21 g) and MS-12 bacterial strain preserved RFW (13.01 g) at 300 mg kg-1 Cd dose significantly better against Cd toxicity than other bacterial strains. In Kabarla MS-7 bacterial strain preserved RDW (3.72 g) at 300 mg kg-1 Cd dose and MS-12 bacterial strain preserved SFW (15.27 g) at 100 mg kg-1 Cd dose significantly better against Cd toxicity than other bacterial strains. Likewise, in YFL, MS-13 bacterial strains preserved MFW (7.509 g) and RL (30.00 cm) at 300 mg kg-1 Cd dose, and MS-7 bacterial strain preserved LA (57.87 cm2) at 100 mg kg-1 Cd dose significantly better against Cd toxicity than other bacterial strains. The results of the study showed that formulations containing Pseudomonas sp. can be used as an agricultural improver in areas with heavy metal pollution. As a result of the study, it was observed that PGPR applications were effective in preserving the morphological and pomological characteristics that decreased with the increase in Cd dose.