High-frequency plant regeneration and genetic homogeneity assessment of regenerants by molecular markers in turmeric (Curcuma longa L.)

A highly efficient and reproducible in vitro plant regeneration method has been developed from shoot bud, half-shoot, and shoot slice explants of four genotypes of turmeric ( Curcuma longa L.). The shoot slice explant produced the highest number of shoots (22.4 shoots explant −1 ) than half-shoot (18.6 shoots explant −1 ) and shoot bud explant (14.2 shoots explant −1 ) of Salem genotype on medium amended with 13.32 µM 6-benzylaminopurine (BAP) and 5.37 µM 1-naphthaleneacetic acid (NAA). Salem genotype was more efficient among the four genotypes tested, followed by Duggirala Red, Prathibha, and PCT-13 genotypes. Approximately 80% of shoots were induced spontaneous rooting on shoot induction media fortified with NAA. The complete plantlets were obtained after rooting the shoots on a medium augmented with 4.90 µM Indole-3-butyric acid (IBA). IBA was an efficient auxin to induce the maximum number of roots per shoot than Indole-3-acetic acid (IAA) and NAA. The plantlets were acclimatized under greenhouse conditions, and the survival rate was recorded as 96%. The plantlets obtained from all explants were morphologically similar to mother plants. Two genome-based molecular markers, namely inter simple sequence repeats (ISSR) and start codon targeted (SCoT) molecular markers, were employed to determine the genetic stability of plants obtained from the tissue culture of the Salem genotype. The DNA markers validated the genetic uniformity of the plants obtained from all three explants was similar to their mother plant. This plant regeneration procedure could be a helpful method for the genetic improvement of turmeric.