In vitro multiplication of heavy metals hyperaccumulator Thlaspi caerulescens

Abstract

A micropropagation protocol through multiple shoot formation was developed for Thlaspi caerulescens L., one of the most important heavy metals hyperaccumulator plants. In vitro seed-derived young seedlings were used for the initiation of multiple shoots on Murashige and Skoog (MS) medium with combinations of benzylaminopurine (BA; 0.5-1.0 mg dm-3), naphthaleneacetic acid (NAA; 0-0.2 mg dm-3), gibberellic acid (GA3; 0-1.0 mg dm-3) and riboflavin (0-3.0 mg dm -3). The maximum number of shoots was developed on medium containing 1.0 mg dm-3 BA and 0.2 mg dm-3 NAA. GA3 (0.5 mg dm-3) in combination with BA significantly increased shoot length. In view of shoot numbers, shoot length and further rooting rate, the best combination was 1.0 mg dm-3 BA + 0.5 mg dm-3 GA 3 + 1.0 mg dm-3 riboflavin. Well-developed shoots (35-50 mm) were successfully rooted at approximately 95 % on MS medium containing 20 g dm-3 sucrose, 8 g dm-3 agar and 1.0 mg dm-3 indolebutyric acid. Almost all in vitro plantlets survived when transferred to pots. © 2008 Institute of Experimental Botany, ASCR.