High efficiency macropropagation of potato (Solanum tuberosum L.) cv. Kufri Jyoti in Kumaun Hills

The present study demonstrated the use of various PGR combinations for efficient in vitro regeneration of cv. kufri jyoti in kumaun hills. Best callus induction and proliferation was observed in MS medium supplemented with 13.59 µM 2,4-D alone and 2,4-D + kinetin (9.06 + 1.16 µM) out of different concentrations of 2,4-D (4.53 to 18.12 µM) alone and 2,4-D (0 to 18.12 µM) with kinetin (1.16 µM). Leaf explants were more efficient in producing callus as compared to internodes. Medium supplemented with BA + GA3 (8.88 µM + 1 µM) initiated shoot induction out of various combinations of BA (4.44 to 13.22 µM) and GA3 (1 µM) after 7 days of incubation with significantly high average number of shoots, average shoot length and average number of leaves per explant. MS medium supplemented with different concentrations of zeatin (4.56, 9.12 and 13.68 µM) with IAA (5.71 µM) and GA3 (8.49 µM) was tried for direct regeneration of shoots through nodes out of which zeatin + IAA + GA3 (13.68 µM + 5.71 µM + 8.49 µM) served to be the best combination and the raised plantlets were found to produce microtubers in a period of 8 to 10 weeks. 2.45 µM IBA in full strength basal MS medium induced highest number of roots. In addition to an efficient regeneration protocol, the microtuber production was also studied in the present piece of work. The research protocol may also be utilized for Agrobacterium tumefaciens mediated transformation towards the biotic and abiotic stress tolerant potato crop.    Key words: In vitro, potato, callus, direct regeneration, microtubers.