Azospirillum sp. Promotes Root Hair Development in Tomato Plants through a Mechanism that Involves Ethylene

By C. Ribaudo, Evelyn M. Krumpholz, F. Cassán, R. Bottini, M. Cantore, J. Curá. Journal of Plant Growth Regulation, 2006

144 citations recorded by the source corpus.

Tomato seeds were inoculated with the plant growth–promoting rhizobacteria Azospirillum brasilense FT326, and changes in parameters associated with plant growth were evaluated 15 days after inoculation. Azospirilla were localized on roots and within xylematic tissue. An increase in shoot and root fresh weight, main root hair length, and root surface indicated that inoculation with A. brasilense FT 326 resulted in plant growth improvement. The levels of indole-3-acetic acid (IAA) and ethylene, two of the phytohormones related to plant growth, were higher in inoculated plants. Exogenously supplied ethylene mimicked the effect of inoculation, and the addition of an inhibitor of its synthesis or of its physiological activity completely blocked A. brasilense growth promotion. Based on our results, we propose that the process of growth promotion triggered by A. brasilense inoculation involves a signaling pathway that has ethylene as a central, positive regulator.

Subfields: Molecular Biology, Plant Science

View Paper: https://www.semanticscholar.org/paper/40daa5af59db959843aa5a046c3298a0f2800710

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In Molecular Biology

1. C. Prigent-Combaret
2. J. Barea
3. D. Jha
4. I. Dodd
5. A. Richardson
6. P. N. Bhattacharyya

In Plant Science

1. J. Barea
2. M. Nogueira
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4. R. Araujo
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6. A. McNeill
7. A. Richardson
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Citations in the corpus

• Co-Inoculation of Soybean with Bradyrhizobium and Azospirillum Promotes Early Nodulation (2015, background): “is an increase in the production of root hairs [21] [22] and in root growth, benefiting plants with better absorption of water and nutrients [23].”
• Chapter Two – How the Plant Growth-Promoting Bacterium Azospirillum Promotes Plant Growth—A Critical Assessment (2010, unknown): “…the improvements are the cause or the References (examples) b Holguin and Glick (2001, 2003), Perrig et al. (2007), Prigent- Combaret et al. (2008), Ribaudo et al. (2006) Cassan et al. (2009a), Perrig et al. (2007), Thuler et al. (2003) Bashan et al. (1990), Jain and Patriquin (1984), Kapulnik et…”
• Acquisition of phosphorus and nitrogen in the rhizosphere and plant growth promotion by microorganisms (2009, background): “2003), and this ability seems to promote root hair development in tomato plants (Ribaudo et al. 2006).”
• Changes in root morphological traits in soybean co-inoculated with Bradyrhizobium spp. and Azospirillum brasilense or treated with A. brasilense exudates (2020, methodology): “The leaf spray application of A. brasilense exudates was performed with a hand sprayer at plant V3 stage (Ritchie et al. 1994).”
• Plant growth-promoting rhizobacteria and root system functioning (2013, background): “Indeed, exogenous ethylene supply to the plant mimicked the effect of Azospirillum brasilense inoculation, while the addition of an ethylene biosynthesis inhibitor blocked this effect (Ribaudo et al., 2006).”
• Scoping the potential uses of beneficial microorganisms for increasing productivity in cotton cropping systems (2015, background): “Certain PGP bacteria, such as Azospirillum brasilense, can produce small amounts of ethylene, which may promote root hair development (Ribaudo et al., 2006).”
• Rhizobacterial mediation of plant hormone status (2010, background): “brasilense FT 236, which almost doubled tomato shoot ethylene production, ACS activity and LeACS2 gene expression (Ribaudo et al., 2006)”
• Plant growth-promoting rhizobacteria (PGPR): emergence in agriculture (2011, background): “IAA-mediated ethylene production could increase root biomass, root hair number and consequently the root surface area of PGPR inoculated tomato plants (Ribaudo et al. 2006).”
• Plant growth promoting rhizobacteria and their potential for biocontrol of phytopathogens (2016, background): “Ribaudo et al. (2006) represented some of the efficient PGPR strains as the producer of different plant growth regulators.”