Tapioca - A New and Cheaper Alternative to Agar for Direct in Vitro Shoot Regeneration and Microtuber Production from Nodal Cultures of Potato

The efficiency of in vitro shoot regeneration and microtuber production of potato (Solanum tuberosum L.) from nodal explants was studied using agar and other new and cheaper gelling agents - tapioca and sago in Murashige & Skoog (MS) salt medium. For shoot regeneration, agar was maintained at 8 mg l -1, tapioca and sago were varied between 9-18 and 10-14 % (w/v), respectively supplemented with 3% sucrose, 0.03 mg l-1 NAA, 0.25 mg l-1 GA3 and 2.5 mg l-1 Ca-panthothnate. The microtuberisation study was done using agar, tapioca and sago at 0.8, 14 and 10% concentration (w/v), respectively, in the presence of benzylaminopurine and paclobutrazol. Type of gelling agent significantly affected in vitro plant regeneration. After 32 days, shoot height and number of nodes respectively were 8.86 cm and 10.5 in agar, and 8.9 -12.1 in 11-15% tapioca, respectively. Tapioca at 14-15% stimulated growth giving significantly (P