ROLE OF PHYTOHORMONE ON IN VITRO PLANT REGENERATION IN SWEET POTATO (Ipomoea batatas L.)

Abstract

An experiment was conducted to develop in vitro regeneration protocol in sweet potato at the Department of Biotechnology, Sher-e-Bangla Agricultural University, Dhaka. Four Sweet potato varieties viz Beni,

Cogane,

Kokei and

Bari12 were used. The phytohormones BA, IBA and 2,4-D were applied to observe the potentiality of each hormone on plantlet production. Meristem was used as explant for callus induction and subsequent plantlet regeneration. The cultivar Cogane took minimum days for shoot regeneration from callus in the treatment 0.5 mg/l of 2,4-D. The highest number of shoots was noticed by the variety Kokei in the same treatment. The treatment 0.5 mg/l of 2,4-D showed best response on callus induction and the variety Kokei was more responsive in plantlet regeneration from meristamatic tissue. The node and shoot tip were used for direct plantlet regeneration on MS media supplemented with different concentration of BA and IBA either individually or in both combination. The treatment 1.0 mg/l of BA resulted the highest length of shoot 7.50 cm, 8.25 cm, 7.90 cm and 8.25 cm in the variety Beni, Cogane, Kokei and BARI 12 respectively. The highest percent of node development was recorded in the variety Kokei. The combined effect of BA and IBA was evaluated for plantlet regeneration and it was noticed that the treatment 1.0 mg/l BA + 2.0 mg/l IBA took minimum days for shoot initiation. The variety BARI 12 and Kokei showed highest number of node in the treatment 1.0 mg/l + 1.5 mg/l IBA. Healthy, robust and good quality plantlets were regenerated in all the four varieties. Among them, the variety Kokei showed the best performance in all the parameter under studies. More than 80% plantlet survived in net house and in open field condition. An efficient protocol has been developed for in vitro regeneration of sweet Potato which can be used for large scale commercial purpose of plantlet production.