Effect of Explant, Type and Concentration of Hormone on Callus Induction and Regeneration of two Iranian Sesame (Sesamum indicum L.) Cultivars

Sesame is an ancient oilseed plant known for its medicinally important lignans and its high quality edible oil. ptimization of tissue culture in order to achieve high frequency regeneration is the first step for genetic transformation. the plant recalcitrant to plant tissue culture thus limiting the use of modern biotechnology for its genetic improvement. Therefore, sesame is one of the plants that need a suitable protocol for its Tissue culture and effective regeneration.

In this study, the rate of callus induction and regeneration three explants (cotyledon1, cotyledon2, hypocotyls) two sesame cultivars (Darab, Dashtestan) tested in different hormones including BAP in five levels (0, 4.5, 5.5, 6.5 and 7.5 mg/l), IAA in four levels (0, 0.5, 1 and 2 mg/l), Agno3 (5 mg/l). The shoots transferred to rooting media after regeneration. The experiment was conducted as a completely randomized design )CRD( with factorial arrangement and 3 replications.

According to the results, regeneration induction in hypocotyls explants and callus induction in cotyledon 1 and cotyledon 2 explants were not observed in any of the genotypes. Results of means comparison revealed best result for traits (fresh weight, dry weight, diameter callus and callus induction) In MS medium containing supplement of 5.5 mg/l BAP and 1 mg/l IAA, 6.5 mg/l BAP and 1 mg/l IAA cultivar Dashtestan, 5.5 and 6.5 mg/l BAP in 1 mg/l IAA cultivar Dashtestan, 5.5 mg/l BAP in 0.5 and 1 mg/l IAA cultivar Dashtestan.

the highest rate of regeneration occurred in cotyledon1 explants with 6.5 mg / l BAP and 1 mg / l IAA. Finally, this medium is an efficient medium for the regeneration of these cultivars of sesame. All shoots formed roots after 15 days and Plantlets were transferred into pot with perlite and Cocopeat bed.