the effect of hormones and photoperiod on in vitro microtuberization of two potato cultivars

the experiment was conducted to study the effect of photoperiod and hormones on production of microtubers for two potato cultivars (sante and savalan), which were clean and pathogens free. this experiment was performed as a factorial experiment based on randomized design with three replications. the results showed that cultivar, hormone and photoperiod would effect on all studied traits. sante cultivar indicates more efficiency for all measured traits than in savalan cultivar. in this experiment by using the combination of two hormones 2, 4-d and bap would increase number, diameter and weight of microtubers. the means comparison of photoperiod showed that highest efficiency for all traits as treatment of plant for 8 hours in darkness plus 16 hours in light plus utter darkness (p3). in this research, the highest number of microtuber was related to cultivar of sante (9.47) is gained with hormone 2, 4-d, as well as photoperiod p3 which this superiority for savalan cultivar is gained by using the combination of two hormones and p3 photoperiod.