2R,3R-Butanediol, a Bacterial Volatile Produced by Pseudomonas chlororaphis O6, Is Involved in Induction of Systemic Tolerance to Drought in Arabidopsis thaliana

• Published in: Molecular plant-microbe interactions Vol. 21; no. 8; pp. 1067 - 1075
• Main Authors: Cho, Song Mi, Kang, Beom Ryong, Han, Song Hee, Anderson, Anne J, Park, Ju-Young, Lee, Yong-Hwan, Cho, Baik Ho, Yang, Kwang-Yeol, Ryu, Choong-Min, Kim, Young Cheol
• Format: Journal Article
• Language: English
• Published: United States The American Phytopathological Society 01-08-2008
• Subjects: abscisic acid; Abscisic Acid - metabolism; Arabidopsis - microbiology; Arabidopsis - physiology; Arabidopsis thaliana; Bacteria; bacterial colonization; biochemical pathways; butanediol; Butylene Glycols - metabolism; Cyclopentanes - metabolism; drought; drought tolerance; ethylene; guard cell; jasmonate; jasmonic acid; metabolites; microbe-associated molecular patterns; Oxylipins - metabolism; plant growth-promoting rhizobacteria; Plant Roots - microbiology; Plant Roots - physiology; Plant Stomata - physiology; Plant Transpiration - physiology; protein kinases; Pseudomonas - metabolism; Pseudomonas chlororaphis; root systems; salicylic acid; Salicylic Acid - metabolism; signal transduction; stomata; stomatal movement; Water - metabolism; water stress; β-aminobutyric acid
• ISSN: 0894-0282; 1943-7706
• DOI: 10.1094/MPMI-21-8-1067

Root colonization of plants with certain rhizobacteria, such as Pseudomonas chlororaphis O6, induces tolerance to biotic and abiotic stresses. Tolerance to drought was correlated with reduced water loss in P. chlororaphis O6-colonized plants and with stomatal closure, indicated by size of stomatal aperture and percentage of closed stomata. Stomatal closure and drought resistance were mediated by production of 2R,3R-butanediol, a volatile metabolite of P. chlororaphis O6. Root colonization with bacteria deficient in 2R,3R-butanediol production showed no induction of drought tolerance. Studies with Arabidopsis mutant lines indicated that induced drought tolerance required the salicylic acid (SA)-, ethylene-, and jasmonic acid-signaling pathways. Both induced drought tolerance and stomatal closure were dependent on Aba-1 and OST-1 kinase. Increases in free SA after drought stress of P. chlororaphis O6-colonized plants and after 2R,3R-butanediol treatment suggested a primary role for SA signaling in induced drought tolerance. We conclude that the bacterial volatile 2R,3R-butanediol was a major determinant in inducing resistance to drought in Arabidopsis through an SA-dependent mechanism.