2R,3R-butanediol, a bacterial volatile produced by Pseudomonas chlororaphis O6, is involved in induction of systemic tolerance to drought in Arabidopsis thaliana.
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.
Cho
Song Mi
SM
Department of Floriculture, Chunnam Techno College, Jeonnam, Korea.
Kang
Beom Ryong
BR
Han
Song Hee
SH
Anderson
Anne J
AJ
Park
Ju-Young
JY
Lee
Yong-Hwan
YH
Cho
Baik Ho
BH
Yang
Kwang-Yeol
KY
Ryu
Choong-Min
CM
Kim
Young Cheol
YC
D000040:Abscisic Acid / Q000378:metabolism; D017360:Arabidopsis / Q000382:microbiology* / Q000502:physiology*; D002072:Butylene Glycols / Q000378:metabolism*; D003517:Cyclopentanes / Q000378:metabolism; D054883:Oxylipins / Q000378:metabolism; D018517:Plant Roots / Q000382:microbiology / Q000502:physiology; D054046:Plant Stomata / Q000502:physiology; D018526:Plant Transpiration / Q000502:physiology*; D011549:Pseudomonas / Q000378:metabolism*; D020156:Salicylic Acid / Q000378:metabolism; D014867:Water / Q000378:metabolism*
D002072:Butylene Glycols; D003517:Cyclopentanes; D054883:Oxylipins; D014867:Water; C026978:2,3-butylene glycol; C011006:jasmonic acid; D000040:Abscisic Acid; D020156:Salicylic Acid