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. 2025 Apr 4:46:e00893.
doi: 10.1016/j.btre.2025.e00893. eCollection 2025 Jun.

Rhizobial, passenger nodule endophytes and phyllosphere bacteria in combination with acyl homoserine lactones enhances the growth and yield of groundnut

Sivakumar Madhan  1 , Yuvasri Errakutty Arunan  1 , Anandham Rangasamy  1 , Balachandar Dananjeyan  1 , Johnson Iruthayasamy  2 , Manimaran Gajendiran  3 , Krishnamoorthy Ramasamy  4 , Raghu Rajasekaran  5 , Vincent Saminathan  6
Affiliations

Rhizobial, passenger nodule endophytes and phyllosphere bacteria in combination with acyl homoserine lactones enhances the growth and yield of groundnut

Sivakumar Madhan et al. Biotechnol Rep (Amst). .

Abstract

Quorum sensing (QS) mechanisms play an essential role in mediating several signals and plant-bacteria interactions, promoting plant growth. This study demonstrated production of multiple Homoserine lactone (HSL) molecules like C6 HSL, C7 HSL, C8 HSL, 3-Hydroxy-C8-HSL and 3-oxo-C14 HSL in rhizobial and passenger endophytes and phyllospheric bacteria which regulated production of plant growth promoting traits viz., indole acetic acid and exo-polysaccharide production, biofilm formation, and motility. Quorum quenching (QQ) molecules like salicylic acid, gallic acid, and disalicylic acid impaired these traits, but exogenous addition of QS molecules (C7HSL and 3-oxo-C14 HSL) restored these inhibitory effects of QQ compounds. The pot culture experiment revealed that the treatment involving Methylobacterium populi TMV7-4 or Enterobacter cloacae S23 with salicylic acid, C7HSL and 3-oxo-C14 HSL significantly enhanced plant growth including root length, nodulation, pod formation, soil available nutrients and plant nutrients uptake. In future field validation is required for the use of QS molecules in improving groundnut production.

Keywords: N-acyl homoserine lactone; Plant growth promoting traits; Salicylic acid; Swarming; Swimming.

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Conflict of interest statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

Fig 1
Fig. 1
Biofilm formation by groundnut associated bacteria in presence of various quorum quenching molecules. The heatmap illustrated the biofilm formation of different bacterial isolates under the influence of various quorum quenching molecules viz., salicylic acid (5 mM), disalicylic acid (0.5 mM), and gallic acid (5 mM). Different colours reflects the strength of biofilm formation.
Fig 2
Fig. 2
Influence of QQ and QS molecules in swimming and swarming motility. The figure represents the impact of quorum quenching molecule (salicylic acid, 0 and 5 mM) and combination of salicylic acid with each 5 µM of C7-HSL and 3-oxo-C14 HSL on (A) swimming, (B) swarming motility of R. pusense S6R2, B. territori KBB5, E. cloacae S23, and M. populi TMV7–4 represented as colony diameter in cm. Error bars indicate the standard error (SE) of three replicates. The same letter (s) above bar are not significantly different from each other as determined by Tukey's HSD test (p < 0.05).
Fig 3
Fig. 3
Correlation analysis of metabolites obtained from the root exudates of groundnut associated bacteria. The resulting network visualization in Cytoscape represents compounds as nodes and significant correlations as edges, with edge thickness proportional to the correlation strength. The metabolites released from the different treatments T1-T17 were correlated and visualized using the Metscape app and the Cytoscape version 3.6.1 software. The blocks in white and purple represents the metabolites involved in various metabolisms as identified by Kyoto Encyclopedia of Genes and Genomes (KEGG) database/Human Metabolome Database.
Fig 4
Fig. 4
Effect of bacterial isolates, QS and QQ molecules on growth and yield of groundnut. The figure illustrates the growth parameters of groundnut plants viz., the number of pods, nodules, root length, shoot length, and dry weight under pot culture conditions. T1: R. pusense S6R2 alone; T2: E. cloacae S23 alone; T3: B. territori KBB5 alone; T4: M. populi TMV7–4 alone; T5: Salicylic acid alone (quorum-quenching molecule); T6: R. pusense S6R2 + SA; T7: E. cloacae S23 + SA; T8: B. territori KBB5 + SA; T9: M. populi TMV7–4 + SA; T10: R. pusense S6R2 + SA + C7HSL + 3-oxo-C14 HSL; T11: E. cloacae S23 + SA + C7HSL + 3-oxo-C14 HSL; T12: B. territori KBB5 + SA + C7HSL + 3-oxo-C14 HSL; T13: M. populi TMV7–4 + SA + C7HSL + 3-oxo-C14 HSL; T14: Quorum-sensing molecule C7HSL (10 µM); T15: Quorum-sensing molecule 3-oxo-C14 HSL (10 µM); T16: Quorum-sensing molecule C7HSL + 3-oxo-C14 HSL; T17: Control. Values represent the mean of three replicates ± standard error (SE). The same letter (s) above bar are not significantly different from each other as determined by Tukey's HSD test (p < 0.05).
Fig 5
Fig. 5
Visual effect of QS molecules in the growth and yield of groundnut. A. Control (untreated) B. Treated with E. cloacae S23 C. Treated with E. cloacae S23 + SA + quorum sensing molecules (C7-HSL and 3-oxo-C14 HSL), D. Treated with Enterobacter cloacae S23 + salicylic acid (SA).
Fig 6
Fig. 6
Effect of bacterial isolates, QS and QQ molecules on soil and plant nutrients. The figure represents available nitrogen (N), phosphorus (P), and potassium (K) in soil and nutrient uptake in plants. T1: R. pusense S6R2 alone; T2: E. cloacae S23 alone; T3: B. territori KBB5 alone; T4: M. populi TMV7–4 alone; T5: Salicylic acid alone (quorum-quenching molecule); T6: R. pusense S6R2 + SA; T7: E. cloacae S23 + SA; T8: B. territori KBB5 + SA; T9: M. populi TMV7–4 + SA; T10: R. pusense S6R2 + SA + C7HSL + 3-oxo-C14 HSL; T11: E. cloacae S23 + SA + C7HSL + 3-oxo-C14 HSL; T12: B. territori KBB5 + SA + C7HSL + 3-oxo-C14 HSL; T13: M. populi TMV7–4 + SA + C7HSL + 3-oxo-C14 HSL; T14: Quorum-sensing molecule C7HSL (10 µM); T15: Quorum-sensing molecule 3-oxo-C14 HSL (10 µM); T16: Quorum-sensing molecule C7HSL + 3-oxo-C14 HSL; T17: Control. Values represent the mean of three replicates ± standard error (SE). The same letter (s) above bar are not significantly different from each other as determined by Tukey's HSD test (p < 0.05).
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References

    1. Liu Z., Li X. A comparative study of oil, protein, and fatty acid content of 12 cultivars of peanut (Arachis hypogaea L.) grown from two regions in Shandong province, China. Crop. Sci. 2023;63:2491–2508. doi: 10.1002/csc2.21014. - DOI
    1. Zanjare S., Suryawanshi A., Zanjare S.S., Shelar V., Balgude Y. Screening of groundnut (Arachis hypogaea L.) genotypes for identification of sources of resistance against leaf spot disease. Legume Res.-Int. J. 2023;46:288–294.
    1. Ghorbani A., Pishkar L., Saravi K.V., Chen M. Melatonin-mediated endogenous nitric oxide coordinately boosts stability through proline and nitrogen metabolism, antioxidant capacity, and Na+/K+ transporters in tomato under NaCl stress. Front. Plant Sci. 2023;14 doi: 10.3389/fpls.2023.1135943. - DOI - PMC - PubMed
    1. Kusari S., Hertweck C., Spiteller M. Chemical ecology of endophytic fungi: origins of secondary metabolites. Chem. Biol. 2012;19:792–798. doi: 10.1016/j.chembiol.2012.06.004. - DOI - PubMed
    1. Chaudhary T., Gera R., Shukla P. Deciphering the potential of rhizobium pusense MB-17a, a plant growth-promoting root endophyte, and functional annotation of the genes involved in the metabolic pathway. Front. Bioeng. Biotechnol. 2021;8 doi: 10.3389/fbioe.2020.617034. - DOI - PMC - PubMed

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