Microtuberization in Potato: Physical & Chemical Factors on Induction & Characterization of Microtubers and Nuclear Seed Production in Potato

Different sugar types were evaluated on microtuberization efficiencies of potato and sucrose was considered to be the best sugar type and 8% sucrose in media was optimized. The media with 5 uM Jasmonic acid resulted the highest number and maximum yield of microtubers than the other growth regulators used and high nitrate content media increased microtuber size. Application of 2 mg/L AgNO3 and propionic acid added media favored the in vitro microtubers formation. Microtuberization in liquid media followed by incubation at 8 h photoperiod promoted the number and fresh weight of microtubers than the other physical supports (agar based, liquid plus cotton and liquid plus sponge) and incubation (0, 8 and 16 h). The larger microtubers (0.5-0.6 cm diameter) showed significantly higher survival capacity than smaller ones (0.3-0.4 cm dia). The dormancy termination and sprouting efficiencies of microtubers were noted best in media with GA3 (100 ppm) treatment, large size of microtubers and dark incubation. The media with 5 uM Jasmonic acid showed maximum accumulation of total sugar, reducing sugar and starch. The vitamin C content of microtubers decreased with the extended storage periods.