Regeneration of safflower genotypes through callus mediated organogenesis using cotyledonary node explants

Abstract

In this study, the cotyledon nodes of five safflower genotypes (Balcı, Linas, inbred lines 24, 25, and 55) were cultured for shoot regeneration via organogenesis in MS medium involving different TDZ (0.1, 0.5, and 1 mg L-1) and NAA (0, 0.2, and 0.5 mg L-1) doses. The highest rate of shoot forming calli was obtained from genotype 25 in all NAA and TDZ combinations, and there was no statistical difference between genotypes 24 and 25. The number of shoots per callus was found to be low in genotypes with a high rate of shoot forming calli. The maximum shoot number was obtained from the cultivar Linas on medium containing 1 mg L-1 TDZ, with 9.6 shoots/per callus and this value was followed by cultivar Balcı cultured at the same dose with 6.7 shoots/per callus. The rooting of safflower genotypes differed depending on the NAA content of the medium. Better rooting was achieved on medium with 2 mg L-1 NAA for Balcı, 1 mg L-1 NAA for Linas, and 0.1 mg L-1 NAA for genotypes 25 and 55. On the other hand, genotype 24 indicated rooting only on medium with 2 mg L-1 NAA, but it was very low. As a result; regeneration of safflower genotypes via callus-mediated organogenesis from cotyledonary explants was varied depending on TDZ and NAA doses, and many shoots were induced in Linas cultivar at 1 mg L-1 TDZ. However, the rooting of the regenerated shoots was quite low at different NAA doses.