title: High atmospheric carbon dioxide-dependent alleviation of salt stress is linked to RESPIRATORY BURST OXIDASE 1 (RBOH1)-dependent H2O2 production in tomato (Solanum lycopersicum).
abstract: Plants acclimate rapidly to stressful environmental conditions. Increasing atmospheric CO2 levels are predicted to influence tolerance to stresses such as soil salinity but the mechanisms are poorly understood. To resolve this issue, tomato (Solanum lycopersicum) plants were grown under ambient (380 μmol mol(-1)) or high (760 μmol mol(-1)) CO2 in the absence or presence of sodium chloride (100mM). The higher atmospheric CO2 level induced the expression of RESPIRATORY BURST OXIDASE 1 (SlRBOH1) and enhanced H2O2 accumulation in the vascular cells of roots, stems, leaf petioles, and the leaf apoplast. Plants grown with higher CO2 levels showed improved salt tolerance, together with decreased leaf transpiration rates and lower sodium concentrations in the xylem sap, vascular tissues, and leaves. Silencing SlRBOH1 abolished high CO2 -induced salt tolerance and increased leaf transpiration rates, as well as enhancing Na(+) accumulation in the plants. The higher atmospheric CO2 level increased the abundance of a subset of transcripts involved in Na(+) homeostasis in the controls but not in the SlRBOH1-silenced plants. It is concluded that high atmospheric CO2 concentrations increase salt stress tolerance in an apoplastic H2O2 dependent manner, by suppressing transpiration and hence Na(+) delivery from the roots to the shoots, leading to decreased leaf Na(+) accumulation.
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.
authors.forename: Changyu
authors.initials: C
authors.lastname: Yi
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.
authors.forename: Kaiqian
authors.initials: K
authors.lastname: Yao
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.
authors.forename: Shuyu
authors.initials: S
authors.lastname: Cai
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.
authors.forename: Huizi
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Xia
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.
authors.forename: Kai
authors.initials: K
authors.lastname: Shi
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.
authors.forename: Jingquan
authors.initials: J
authors.lastname: Yu
authors.affiliation: Centre for Plant Sciences, School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK.
authors.forename: Christine Helen
authors.initials: CH
authors.lastname: Foyer
authors.affiliation: Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China yanhongzhou@zju.edu.cn.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Zhou
mesh_terms: D001272:Atmosphere; D002245:Carbon Dioxide / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000378:metabolism*; D019255:NADPH Oxidases / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D012965:Sodium Chloride; D013312:Stress, Physiological
chemical_list: D010940:Plant Proteins; D002245:Carbon Dioxide; D012965:Sodium Chloride; D006861:Hydrogen Peroxide; D019255:NADPH Oxidases; C000611454:respiratory burst oxidase 1, tomato
keywords: CO2 enrichment; NADPH oxidase; Na+/K+ homeostasis; reactive oxygen species; salt overly sensitive (SOS) signalling pathway; transpiration.