Poster: Temperature responses

Abs # 126: Double hydrogen peroxide treatment induced a chilling tolerance response in mung bean seedlings equivalent to cold acclimation.

Presenter:	Hung, Shu-Hsien , shhung@mail.dyu.edu.tw
Authors	Hung, Shu-Hsien  (A)   Wang, Chun-Chi  (B)   Yeh, Yi-Fang  (A)   Chiu, Hui-Ming  (A)   Yu, Chih-Wen Yu  (B)   Lin, Chin-Ho  (C)
Affiliations:	(A): Department of Bioindustrial Biotechnology, Da Yeh University, Changhua, Taiwan (B): Department of Molecular Biotechnology, Da Yeh University, Changhua, Taiwan (C): Life Science Department, National Chung Hsing University, Taichung, Taiwan

Mung bean seedlings (Vigna radiata L. cv. TN5, a chilling-senstive cultivar) were pre-treated with 200 mM hydrogen peroxide followed by chilling at 4^oC for 36 h to evaluate changes in chilling tolerance. Seedlings pretreated twice with 200 mM hydrogen peroxide followed by chilling at 4^oC for 36 h had lower electrolyte leakage than did seedlings treated once with hydrogen peroxide and untreated control plants. Double treatments separated by time intervals (0, 1, 2, 3, 4, 5 or 6 h) showed that plants pretreated with a 3 h interval had a similar electrolyte leakage, as did cold-acclimated (10^oC, 48 h) plants. Application of EGTA, a specific calcium chelator, reversed the protection against chilling stress provided to seedlings by hydrogen peroxide pretreatment. These results suggest that acclimation of mung bean seedlings by pretreatment with hydrogen peroxide is mediated through modification of plant calcium signaling. (This work was supported by the Grants from National Science Council, Taiwan. NSC90-2311-B005-008)