Abscisic acid and sucrose affect in vitro tuber formation in yam (Dioscorea rotundata Poir.) plants

Yam tuber (Dioscorea rotundata Poir.) is a staple for many populations in the Colombian Atlantic Coastland and the Caribbean basin, and its demand has recently increased in the international market; however, conventional crops practices negatively affect the quantity and quality of production. In order to provide mechanisms for the production of high quality planting material for yam, the effect of three sucrose concentrations combined with four abscisic acid levels on in vitro growing of microtubers from nodal explants was evaluated. Treatments were distributed using a complete randomized design, and the analysis of variance and Duncan´s Multiple Range Test showed that plant growth variables as well as microtuber number were significantly affected byABA/sucrose levels. Sucrose dose of 60 g L-1 combined with 3.0 mg L-1 of ABA induced the highest number of microtubers, while plants cultured in a medium supplied with 90 g L-1 of sucrose developed more stems, leaves and roots.