Phosphate solubilizing bacteria from soils with varying environmental conditions: Occurrence and function

• Published in: PloS one Vol. 18; no. 12; p. e0289127
• Main Authors: Janati, Walid, Bouabid, Rachid, Mikou, Karima, Ghadraoui, Lahsen El, Errachidi, Faouzi
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 08.12.2023; Public Library of Science (PLoS)
• Subjects: Abiotic stress; Agricultural production; Agrochemicals; Analysis; Bacteria; Biochemical characteristics; Biochemistry; Climate; Climate change; Climatic conditions; Crop diseases; Crop yields; Environmental aspects; Environmental conditions; Environmental factors; Environmental impact; Environmental quality; Evolution & development; Fertilizers; Health aspects; Mediterranean climate; Metabolites; Microorganisms; Mineral fertilizers; Nitrogen; Nutrient status; Nutrients; Phosphates; Phosphorus; Physical characteristics; Plant growth; Population density; Precipitation; Soil analysis; Soil bacteria; Soil microbiology; Soil microorganisms; Soil nutrients; Soil properties; Soil temperature; Soil texture; Soils; Solubilization; Strains (organisms); Temperature; Texture; Morocco
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0289127

Phosphate solubilizing bacteria (PSB) is an advantageous way to supply phosphate (P) to plants. The Mediterranean climate of Morocco, especially the low-lying areas, is semi-arid with nutrient-depleted soils in which small-scale, low-income farmers dominate without access to expensive inorganic fertilizers. However, there is not a wide range of PSBs suitable for various agroecological situations. Furthermore, our understanding of the soil and climatic variables that influence their development is limited. This study aims to examine the impacts of specific environmental factors, such as climate and soil, on the abundance, potential, and diversity of PSBs in four agricultural regions of Morocco. To assess the possible impact of these factors on the P solubilization capacity of PSBs and plant growth-promoting (PGP) traits, we analyzed the soil and climate of each sample studied. Similarly, we tested the P solubilization efficiency of the isolates. The bacteria were isolated in a National Botanical Research Institute's phosphate (NBRIP) agar medium. A total of 51 PSBs were studied in this work. The P-solubilization average of Rock P (RP) and Tricalcium P (TCP) of all strains that were isolated from each of the four regions ranged from 18.69 mg.L-1 to 40.43 mg.L-1 and from 71.71 mg.L-1 to 94.54 mg.L-1, respectively. The PGP traits of the isolated strains are positively correlated with the PSBs abundance and the sample characteristics (soil and climate). The morphological and biochemical characteristics of the strain allowed us to identify around nine different bacterial genera, including Bacillus, Pseudomonas, and Rhizobium. The findings showed that bacterial communities, density, and potency are closely correlated to various edapho-climatic conditions such as temperature, precipitation, soil nutrient status, and soil texture. These findings could be used to improve an effective plant-PSBs system and increase agricultural output by taking into account their specific ecological traits and plant growth mechanisms.