TẠP CHÍ SINH HỌC, 2012, 34(3SE): 257-264 257 THE INCREASE IN IN VITRO SHOOT MULTIPLICATION RATE OF Dendrocalamus asper (Schult. f.) Back. ex Heyne Tran Trong Tuan * , Huynh Le Thien Tu, Do Dang Giap, Thai Xuan Du Institute of Tropical Biology, VAST, tuan216@gmail.com ABSTRACT: A method for micropropagation was developed for Dendrocalamus asper, an economically and environmentally important bamboo. Disinfected seeds were cultured in flasks containing 20 ml of Murashige and Skoog’s medium (MS) supplemented with BA (1.0-7.0 mg l -1 ) or kinetin (1.0-7.0 mg l -1 ). Multiple shoots (6.53) were formed on MS medium supplemented with 3.0 mg l -1 BA and reached 1.49 cm in length. Continuous shoot proliferation was achieved on a MS medium supplemented with BA (1.0-7.0 mg l -1 ). The multiplication rate of 3.30 fold was achieved on MS medium supplemented with 3.0 mg l -1 BA. Propagules were excised from multiple shoots and transferred to rooting medium. After 4 weeks, high in vitro rooting was achieved on MS supplemented with 7.0 mg l -1 IBA. 3.70 cm in length root system developed 8.0-9.0 roots in 28 days. A high rate of plant survival (85%) was obtained within 2 weeks. Keywords: Dendrocalamus asper, BA, IBA, kinetin, micropropagation, NAA. INTRODUCTION The industrial revolution from 1800s to 1900s not only developed the global economics, but also emitted 850 billion tons of CO 2 into environment through combustion of fossil fuels, oil, coal and gas... Besides, changes in land use and deforestation added 370 billion tons of CO 2 . Human activities not only produce a huge amount of CO 2 , but they also damage the forests-carbon sinks of the planet. There are difficulties for human to make a balance between economical development and environmental protection. Bamboo tree absorbs CO 2 through photosynthesis and generates up to 35% more oxygen then an equivalent stand of tree. After 3 to 5 years, each hectare of mature bamboo sequesters 62 tons of CO 2 per year [18]. Bamboo is well-developed, expand rapidly and is a multipurpose tropical clumping bamboo with high economic value. The important fact is that bamboo can be harvested without the destruction. Alexander and Rao (1968) [1] described the first research on bamboo embryo culture. The technique of release of protoplast from bambusa leaf tissue has been reported [17]. Mehta et al. (1982) [8] were successful in regeneration of bamboo plantlets via somatic embryogenesis. Micropropagation of D. hamiltonii has been reported [16] on MS medium [10] with 2.5 mg l -1 BA. Godbole et al. (2002) [6] used nodal segments to regenerate D. hamiltonii via somatic embryogenesis on MS medium with BA (2.5 mg l - 1) and 2,4-D (1.0 mg l -1 ). Lin et al. (2004) [7] reported the role of TDZ in the induction of somatic embryogenesis of Bambusa edulis. High germination rate of somatic embryogenesis (80%) was achieved on medium supplemented with 0.455 M TDZ. D. asper plays an important role in daily life, thus it becomes one of important cultivated crops in Vietnam and several countries of the Asia-Pacific region. The mature culms are utilized in construction, decoration, and they are suitable for pulp, paper, matting and rayon. Moreover, D. asper is cultivated at highland, bare hill, coastal regions... to against soil erosion and it is also an important source for handicraft villages. Tender shoot of D. asper is not only a high quality food, but also an important export commodity. For some problems, the traditional methods for propagation of D. asper are time-consuming and difficult. Vegetative propagation such as cutting and rhizomes are bulky, tricky to handle, transport and very slow to grow. Thus, the plant cell culture protocols of D. asper were described. Singh et al. (2003) [15] reported a simple method for large-scale propagation of D. asper via culm and culm-branch. Two steps method for accelerated mass propagation of D. asper via nodal segments was described [3].