Synergistic Strategies for Overcoming Salt Stress in Strawberry Farming: The Use of Organic Fertilizers and Plant Growth Promoting Rhizobacteria (PGPR)

The study was carried out under salt-stress conditions, and three non-microbial commercial organic fertilizers purchased from Humintech GmbH (Grevenbroich, Germany) were applied to the soil for strawberry plants. The three promoters were Fulvagra®, based on fulvic acid, Liqhumus®, based on humic acid, and Microsense Root®, also based on humic acid. Treatment with Fulvagra® resulted in a remarkable 69.90% increase in average fruit weight and a 39.52% increase in yield in strawberry plants. These improvements remained significant when combined with plant growth promoting rhizobacteria (PGPR), resulting in a 61.81% increase in fruit weight and a 45.21% increase in yield. Liqhumus® treatment resulted in a significant 49.95% increase in fruit weight and a 39.30% increase in fruit yield. The introduction of PGPR further enhanced these effects by increasing fruit weight by 87.70% and yield by 63.84%. The Microsense Root® treatment showed 31.07 and 61.87% improvements for the respective parameters. In conjunction with this treatment, the use of PGPR produced the most significant results, with increases of 121.14 and 65.37% for respective parameters. These results indicate that the combined use of non-microbial commercial organic fertilizers with PGPR leads to higher efficiency and is promising for sustainable agricultural practices, particularly in improving the resistance of strawberry plants to salt-induced stress.