Two potato varieties namely, kufri bahar and kufri surya were tested for in vitro tuberization response to a same culture medium supplemented with three levels of 6-benzly aminopurine (0.75 mg/l, 1.5 mg/l, 2.25 mg/l) in a completely randomized block design. The study was conducted in the Central Potato Research Institute (CPRI), Modipuram, Meerut Campus, and India during the period of 2012-13 & 2013-14. The objective was to determine optimum concentration of 6-benzly aminopurine for tuberization. Both varieties, exhibited a better response when the culture medium supplemented with 2.25 mg/l of 6-benzylaminopurine than the other concentrations and control for mean values of number of days for tuber initiation microtuber number, fresh weight of microtubers and number of eyes per microtuber was found optimum and it may be useful to enhance tuber quality as well as crop growth under in vitro conditions at farmer and industrial levels.

Keywords: in vitro plantlets, potato cultivars, 6-benzylaminopurine, in vitro plants.