title: Hydrogen sulfide alleviates aluminum toxicity in germinating wheat seedlings.
abstract: Protective role of hydrogen sulfide (H(2)S) on seed germination and seedling growth was studied in wheat (Triticum) seeds subjected to aluminum (Al(3+)) stress. We show that germination and seedling growth of wheat is inhibited by high concentrations of AlCl(3). At 30 mmol/L AlCl(3) germination is reduced by about 50% and seedling growth is more dramatically inhibited by this treatment. Pre-incubation of wheat seeds in the H(2)S donor NaHS alleviates AlCl(3)-induced stress in a dose-dependant manner at an optimal concentration of 0.3 mmol/L. We verified that the role of NaHS in alleviating Al(3+) stress could be attributed to H(2)S/HS(-) by showing that the level of endogenous H(2)S increased following NaHS treatment. Furthermore, other sodium salts containing sulfur were ineffective in alleviating Al(3+) stress. NaHS pretreatment significantly increased the activities of amylases and esterases and sustained much lower levels of MDA and H(2)O(2) in germinating seeds under Al(3+) stress. Moreover, NaHS pretreatment increased the activities of guaiacol peroxidase, ascorbate peroxidase, superoxide dismutase and catalase and decreased that of lipoxygenase. NaHS pretreatment also decreased the uptake of Al(3+) in AlCl(3)-treated seed. Taken together these results suggest that H(2)S could increase antioxidant capability in wheat seeds leading to the alleviation of Al(3+) stress.
authors.affiliation: School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009, China. zhandzhy@yahoo.com.cn
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Zhu-Qin
authors.initials: ZQ
authors.lastname: Tan
authors.forename: Lan-Ying
authors.initials: LY
authors.lastname: Hu
authors.forename: Song-Hua
authors.initials: SH
authors.lastname: Wang
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Luo
authors.forename: Russell L
authors.initials: RL
authors.lastname: Jones
mesh_terms: D000535:Aluminum / Q000633:toxicity*; D000975:Antioxidants / Q000378:metabolism; D060387:Ascorbate Peroxidases; D002374:Catalase / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D018525:Germination; D006861:Hydrogen Peroxide / Q000378:metabolism; D006862:Hydrogen Sulfide / Q000494:pharmacology; D008315:Malondialdehyde / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D010544:Peroxidases / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D013440:Sulfides / Q000494:pharmacology*; D013482:Superoxide Dismutase / Q000378:metabolism; D014908:Triticum / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism
chemical_list: D000975:Antioxidants; D013440:Sulfides; D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D000535:Aluminum; D010544:Peroxidases; C121048:guaiacol peroxidase; D060387:Ascorbate Peroxidases; D002374:Catalase; D009195:Peroxidase; D013482:Superoxide Dismutase; D006862:Hydrogen Sulfide