Isolation of highly efficient potassium solubilizing bacteria and their effects on nutrient acquisition and growth promotion in tobacco seedlings

Abstract Background Tobacco plants are typically high potassium (K)-demanding during growth and development, but the bioavailability of the nutrient in tobacco-growing soils is often limited. Aim and methodology The present study aimed at screening highly efficient potassium-solubilizing bacteria (K...

Full description

Saved in:
Bibliographic Details
Main Authors: Jia-ning Gao, Meng-tao Xu, Ernest Uwiringiyimana
Format: Article
Language:English
Published: BMC 2025-06-01
Series:BMC Plant Biology
Subjects:
Online Access:https://doi.org/10.1186/s12870-025-06760-y
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849434246438977536
author Jia-ning Gao
Meng-tao Xu
Ernest Uwiringiyimana
author_facet Jia-ning Gao
Meng-tao Xu
Ernest Uwiringiyimana
author_sort Jia-ning Gao
collection DOAJ
description Abstract Background Tobacco plants are typically high potassium (K)-demanding during growth and development, but the bioavailability of the nutrient in tobacco-growing soils is often limited. Aim and methodology The present study aimed at screening highly efficient potassium-solubilizing bacteria (KSB) through in vitro experiments, and to grasp their potential role in mineral dissolution for nutrients release. The effects of these bacterial inoculants on soil nutrient bioavailability, macronutrient acquisition, soil bacterial community characteristics, and tobacco seedling biomass were investigated through a greenhouse pot experiment. Results The in vitro experiments showed that the SKL51 (Paenibacillus sp.), SKT41 (Klebsiella oxytoca), and PTG11 (Enterobacter hormaechei) strains were more efficient at solubilizing K than the reference strain RT (Bacillus mucilaginosus). During the 7-day incubation with K-feldspar, the average solubilized potassium by SKL51, SKT41 and PTG11 was 28.8 ± 6.8, 30.1 ± 6.7 and 29.1 ± 1.0 μg mL−1, respectively. The highest potential K solubility enhanced by the three KSB was 55.1%, 39.0% and 41.1%, respectively. Additionally, these bacteria exhibited differences in their potential to solubilize other nutrients, with SKT41 enhancing the dissolution of feldspar the most for Si4+ (13.2 ± 2.9 μg mL−1), PTG11 for Ca2+ (174.1 ± 29.4 μg mL−1) and SKL51 for Mg2+ (52.7 ± 3.0 μg mL−1). The three KSB secreted various low-molecular-weight organic acids (LMWOAs) that were variably correlated with solubilized mineral nutrients. The results of the greenhouse pot experiment showed that soil inoculation with PTG11 was the most effective at increasing seedling height by 45% and dry biomass by 83%. The relative abundances of Acinetobacter, Asaia, Bacillus, Bacteroides, Faecalibacterium, Pseudoclavibacter and Sphingomonas, which are associated with the development of both root systems and plant aboveground parts increased significantly (p < 0.05), thereby contributing to shifts in soil bacterial community structure and correlating with improved soil properties. Conclusion PTG11 and SKL51 had significant effects on soil bacterial community structure, and nutrient mobilization, thereby promoting plant growth in support of ecological benefits and environmental friendliness.
format Article
id doaj-art-2f54f4a78f094b279b28a458d30c84b7
institution Kabale University
issn 1471-2229
language English
publishDate 2025-06-01
publisher BMC
record_format Article
series BMC Plant Biology
spelling doaj-art-2f54f4a78f094b279b28a458d30c84b72025-08-20T03:26:43ZengBMCBMC Plant Biology1471-22292025-06-0125111910.1186/s12870-025-06760-yIsolation of highly efficient potassium solubilizing bacteria and their effects on nutrient acquisition and growth promotion in tobacco seedlingsJia-ning Gao0Meng-tao Xu1Ernest Uwiringiyimana2College of Tourism and Geographical Science, Leshan Normal UniversityCollege of Tourism and Geographical Science, Leshan Normal UniversityInstitute of Soil Science, Chinese Academy of SciencesAbstract Background Tobacco plants are typically high potassium (K)-demanding during growth and development, but the bioavailability of the nutrient in tobacco-growing soils is often limited. Aim and methodology The present study aimed at screening highly efficient potassium-solubilizing bacteria (KSB) through in vitro experiments, and to grasp their potential role in mineral dissolution for nutrients release. The effects of these bacterial inoculants on soil nutrient bioavailability, macronutrient acquisition, soil bacterial community characteristics, and tobacco seedling biomass were investigated through a greenhouse pot experiment. Results The in vitro experiments showed that the SKL51 (Paenibacillus sp.), SKT41 (Klebsiella oxytoca), and PTG11 (Enterobacter hormaechei) strains were more efficient at solubilizing K than the reference strain RT (Bacillus mucilaginosus). During the 7-day incubation with K-feldspar, the average solubilized potassium by SKL51, SKT41 and PTG11 was 28.8 ± 6.8, 30.1 ± 6.7 and 29.1 ± 1.0 μg mL−1, respectively. The highest potential K solubility enhanced by the three KSB was 55.1%, 39.0% and 41.1%, respectively. Additionally, these bacteria exhibited differences in their potential to solubilize other nutrients, with SKT41 enhancing the dissolution of feldspar the most for Si4+ (13.2 ± 2.9 μg mL−1), PTG11 for Ca2+ (174.1 ± 29.4 μg mL−1) and SKL51 for Mg2+ (52.7 ± 3.0 μg mL−1). The three KSB secreted various low-molecular-weight organic acids (LMWOAs) that were variably correlated with solubilized mineral nutrients. The results of the greenhouse pot experiment showed that soil inoculation with PTG11 was the most effective at increasing seedling height by 45% and dry biomass by 83%. The relative abundances of Acinetobacter, Asaia, Bacillus, Bacteroides, Faecalibacterium, Pseudoclavibacter and Sphingomonas, which are associated with the development of both root systems and plant aboveground parts increased significantly (p < 0.05), thereby contributing to shifts in soil bacterial community structure and correlating with improved soil properties. Conclusion PTG11 and SKL51 had significant effects on soil bacterial community structure, and nutrient mobilization, thereby promoting plant growth in support of ecological benefits and environmental friendliness.https://doi.org/10.1186/s12870-025-06760-yPotassium solubilizing bacteriaBiomassMacronutrient acquisitionSoil bacterial community structureTobacco seedling growth promotion
spellingShingle Jia-ning Gao
Meng-tao Xu
Ernest Uwiringiyimana
Isolation of highly efficient potassium solubilizing bacteria and their effects on nutrient acquisition and growth promotion in tobacco seedlings
BMC Plant Biology
Potassium solubilizing bacteria
Biomass
Macronutrient acquisition
Soil bacterial community structure
Tobacco seedling growth promotion
title Isolation of highly efficient potassium solubilizing bacteria and their effects on nutrient acquisition and growth promotion in tobacco seedlings
title_full Isolation of highly efficient potassium solubilizing bacteria and their effects on nutrient acquisition and growth promotion in tobacco seedlings
title_fullStr Isolation of highly efficient potassium solubilizing bacteria and their effects on nutrient acquisition and growth promotion in tobacco seedlings
title_full_unstemmed Isolation of highly efficient potassium solubilizing bacteria and their effects on nutrient acquisition and growth promotion in tobacco seedlings
title_short Isolation of highly efficient potassium solubilizing bacteria and their effects on nutrient acquisition and growth promotion in tobacco seedlings
title_sort isolation of highly efficient potassium solubilizing bacteria and their effects on nutrient acquisition and growth promotion in tobacco seedlings
topic Potassium solubilizing bacteria
Biomass
Macronutrient acquisition
Soil bacterial community structure
Tobacco seedling growth promotion
url https://doi.org/10.1186/s12870-025-06760-y
work_keys_str_mv AT jianinggao isolationofhighlyefficientpotassiumsolubilizingbacteriaandtheireffectsonnutrientacquisitionandgrowthpromotionintobaccoseedlings
AT mengtaoxu isolationofhighlyefficientpotassiumsolubilizingbacteriaandtheireffectsonnutrientacquisitionandgrowthpromotionintobaccoseedlings
AT ernestuwiringiyimana isolationofhighlyefficientpotassiumsolubilizingbacteriaandtheireffectsonnutrientacquisitionandgrowthpromotionintobaccoseedlings