Rashid Raina, Iqbal Atia, Shahzad Muhammad, Noureen Sidra, Muqeet Hafiz Abdul
Department of Microbiology and Molecular Genetics, The Women University, Multan 66000, Pakistan.
Department of Electrical Engineering, Muhammad Nawaz Sharif University of Engineering and Technology, Multan 66000, Pakistan.
Plants (Basel). 2025 Jul 8;14(14):2096. doi: 10.3390/plants14142096.
Plant growth-promoting rhizobacteria (PGPR) are beneficial soil microorganisms that enhance plant growth and stress tolerance through various mechanisms, including phytohormone production, EPS production, phosphate solubilization, and extracellular enzyme production. These bacteria establish endosymbiotic relationships with plants, improving nutrient availability and overall crop productivity. Despite extensive research on PGPR isolation, their practical application in agricultural fields has faced challenges due to environmental stresses and limited survival during storage. To address these limitations, the present study aimed to isolate salt-tolerant bacterial strains and formulate them with organic carriers to enhance their stability and effectiveness under saline conditions. The isolated bacterial strains exhibited high salt tolerance, surviving NaCl concentrations of up to 850 millimolar. These strains demonstrated basic key plant growth-promoting traits, including phosphate solubilization, auxin production, and nitrogen fixation. The application of carrier-based formulations with both strains, (RR2) and (RR3), improved physiological and biochemical parameters in wheat plants subjected to salinity stress. The treated plants, when subjected to salinity stress, showed notable increases in chlorophyll a (73.3% by Peat + RR3), chlorophyll b (41.1% by Compost + RR3), carotenoids (51.1% by Peat + RR3), relative water content (77.7% by Compost + RR2), proline (75.8% by compost + RR3), and total sugar content (12.4% by peat + RR2), as compared to the stressed control. Plant yield parameters such as stem length (35.1% by Peat + RR3), spike length (22.5% by Peat + RR2), number of spikes (67.6% by Peat + RR3), and grain weight (39.8% by Peat + RR3) were also enhanced and compared to the stressed control. These results demonstrate the potential of the selected salt-tolerant PGPR strains (ST-strains) to mitigate salinity stress and improve wheat yield under natural field conditions. The study highlights the significance of carrier-based PGPR applications as an effective and sustainable approach for enhancing crop productivity in saline-affected soils.
植物促生根际细菌（PGPR）是有益的土壤微生物，它们通过多种机制促进植物生长并提高植物的抗逆性，这些机制包括植物激素产生、胞外多糖产生、磷素溶解以及胞外酶产生。这些细菌与植物建立内共生关系，提高养分有效性和整体作物生产力。尽管对PGPR的分离进行了广泛研究，但由于环境压力和储存期间存活率有限，它们在农业领域的实际应用面临挑战。为了解决这些限制，本研究旨在分离耐盐细菌菌株并用有机载体将它们制成制剂，以提高其在盐胁迫条件下的稳定性和有效性。分离出的细菌菌株表现出高耐盐性，在高达850毫摩尔的氯化钠浓度下仍能存活。这些菌株表现出基本的关键植物促生特性，包括磷素溶解、生长素产生和固氮作用。用菌株（RR2）和（RR3）制成的基于载体的制剂的应用，改善了遭受盐胁迫的小麦植株的生理和生化参数。与胁迫对照相比，经处理的植株在遭受盐胁迫时，叶绿素a（泥炭+RR3处理下增加73.3%）、叶绿素b（堆肥+RR3处理下增加41.1%）、类胡萝卜素（泥炭+RR3处理下增加51.1%）、相对含水量（堆肥+RR2处理下增加77.7%）、脯氨酸（堆肥+RR3处理下增加75.8%）和总糖含量（泥炭+RR2处理下增加12.4%）均有显著增加。植株产量参数如茎长（泥炭+RR3处理下增加35.1%）、穗长（泥炭+RR2处理下增加22.5%）、穗数（泥炭+RR3处理下增加67.6%）和粒重（泥炭+RR3处理下增加39.8%）也有所提高，并与胁迫对照进行了比较。这些结果证明了所选耐盐PGPR菌株（ST-菌株）在自然田间条件下减轻盐胁迫和提高小麦产量的潜力。该研究强调了基于载体的PGPR应用作为一种有效且可持续的方法来提高盐渍化土壤中作物生产力的重要性。
