Role of plant growth regulators on shoot development of shoot apical meristems of banana genotypes

摘要

This study aimed to elucidate the role of plant growth regulators on development of shoot apical meristems (SAMs) of banana genotypes. SAM culture offers an efficient method for rapid clonal propagation and production of pathogen-free material, preservation and international exchange of germplasm. The banana genotypes that were used in this study are 'Cau Man" (AA), 'Bom' (AA), wild-1 [Musa acuminata), 'Gia Huong' (AAA), 'Gia Cui' (AAA), 'Laba' (AAA), 'Su' (AAB), 'Cha Den' (MB), 'Cha Bot' (AAB), 'La' (ABB), 'Hot' (BB), and 'Mat' (BBB), 'Ngu' (BBB), 'Sap' (BBB). The combination of 0.17 mg L1 indol acetic acid (IAA) and 2.5 mg L1 N6-benzyladenine (BA) or 1 mg L 1 zeatin; or 0.17 mg L 1 IAA, 2.5 mg L1 BA and 1 mg L 1 zeatin induced cell division in the SAM to form new shoots in all the cultivars. Shoot apical meristems of in vitro and field plants were cultured on the CHP (highly proliferating culture) medium with 0.17 mg L 1 IAA, 2.5 mg L1 BA, and 1 mg L1 zeatin. Morphological and physiological changesin shoot development were analyzed. The size of shoot apical meristem, respiration rate, and content of endogenous level of IAA, zeatin and gibberellins in shoot tip of the plants with genotype A are higher than those in plants with genotype B. The correlation of genotype, plant growth regulators and shoot development was discussed. Factors such as genotype (genome group), metabolism (respiration rate) and plant growth regulators considerably influenced the shoot development from SAM in the banana genotypes. The combination of IAA (0.17 mg L'), BA (2.5 mg L ') and zeatin (1 mg L -') strongly induced cell division in SAM to form new shoots.