Comparative transcriptome profiling provides insights into the growth promotion activity of Pseudomonas fluorescens strain SLU99 in tomato and potato plants

Abstract

The use of biocontrol agents with plant growth-promoting activity has emerged as an approach to support sustainable agriculture. During our field evaluation of potato plants treated with biocontrol rhizobacteria, four bacteria were associated with increased plant height. Using two important solanaceous crop plants, tomato and potato, we carried out a comparative analysis of the growth-promoting activity of the four bacterial strains: Pseudomonas fluorescens SLU99, Serratia plymuthica S412, S. rubidaea AV10, and S. rubidaea EV23. Greenhouse and in vitro experiments showed that P. fluorescens SLU99 promoted plant height, biomass accumulation, and yield of potato and tomato plants, while EV23 promoted growth in potato but not in tomato plants. SLU99 induced the expression of plant hormone-related genes in potato and tomato, especially those involved in maintaining homeostasis of auxin, cytokinin, gibberellic acid and ethylene. Our results reveal potential mechanisms underlying the growth promotion and biocontrol effects of these rhizobacteria and suggest which strains may be best deployed for sustainably improving crop yield.

Genomic Insights and Biocontrol Potential of Ten Bacterial Strains from the Tomato Core Microbiome

“…In the trials, the endophytic bacteria were applied to tomato plants by soil drenching and to seeds by seed coating. Importantly, given the diverse biocontrol mechanisms employed by bacteria, which include competing for resources, niche exclusion, and the production of antimicrobial compounds, it is possible that our bacteria may have the capability to induce systemic resistance in the tomato plants (Compant et al, 2005; Lugtenberg and Kamilova, 2009; Singh et al, 2011; Pieterse et al, 2014; Hardoim et al, 2015; Santoyo et al, 2016; Hanifah et al, 2023; Kelbessa et al, 2023).…”

“…Plant-associated microorganisms play vital roles in protecting plants against abiotic and biotic stress factors (Vessey, 2003; Compant et al, 2005; Singh et al, 2011; Santoyo et al, 2016; Backer et al, 2018; Kelbessa et al, 2023). Some constituents of the plant microbiota actively enhance nutrient uptake, improve nutrient utilization efficiency, and contribute to phytohormone modulation, biocontrol, and the induction of systemic resistance, thereby promoting plant growth and health (Vessey, 2003; Compant et al, 2005; Singh et al, 2011; Pieterse et al, 2014; Santoyo et al, 2016; Backer et al, 2018; Das et al, 2022; Hanifah et al, 2023; Kelbessa et al, 2023). These microorganisms are known as Plant Growth Promoting Microorganisms (PGPM) (Lugtenberg and Kamilova, 2009; Kumar et al, 2022).…”

Metabolic Processes and Biological Macromolecules Defined the Positive Effects of Protein-Rich Biostimulants on Sugar Beet Plant Development

“…This down-regulation might be a result of the storage of sugar in sugar beet roots. It is well known that respiration is a catabolic process that results in the breakdown of sugars or other respiration substrates in order to release energy and carbon dioxide [31]. Thus, a down-regulation of the metabolic processes in the sugar beet roots may prevent respiration, thereby enhancing sugar storage in the root of the sugar beet plant.…”

“…qRT-PCR analysis was carried out as described previously [31]. Briefly, 500 ng of total RNA was used for reverse transcription using an iScript cDNA synthesis kit (BioRad, Hercules, CA, USA).…”