Direct in vitro regeneration of medicinally important Indian and exotic red-colored ginger (Zingiber officinale Rosc.) and genetic fidelity assessment using ISSR and SSR markers

An efficient direct in vitro plant regeneration protocol has been established for medicinally important red-colored ginger (Zingiber officinale Rosc.) genotypes, namely, northeast red ginger and exotic red ginger. Shoot, root initiation, and growth response of these two genotypes to five different concentrations of 6-benzylaminopurine (BAP; 1.0, 2.0, 3.0, 4.0, and 5.0 mg L⁻¹) and a control using Murashige and Skoog (MS) medium were studied. The two red ginger genotypes responded differently to five concentrations of hormone. Significantly higher shoot multiplication was observed for northeast red ginger cultured on medium containing 3.0 mg L⁻¹ BAP. In the case of exotic red ginger, maximum shoot multiplication was on medium containing 5.0 mg L⁻¹ BAP and was statistically on par with medium supplemented with 4.0 mg L⁻¹ BAP. Maximum shoot length was measured when cultured on medium containing 3.0 mg L⁻¹ BAP in northeast red ginger and medium with 2.0 mg L⁻¹ BAP in exotic red ginger. In exotic red ginger, the highest number of roots was documented on medium containing 5.0 mg L⁻¹ BAP and medium with 3.0 mg L⁻¹ BAP in northeast red ginger, which was on par with medium containing 2.0 mg L⁻¹. The exotic red ginger had significantly longer root length on medium containing 2.0 mg L⁻¹ BAP. However, root length was on par when northeast red ginger was cultured on medium containing 2.0 to 5.0 mg L⁻¹ BAP. Inter-simple sequence repeat (ISSR) and simple sequence repeat (SSR) markers confirmed the genetic fidelity of the regenerated plantlets. The direct in vitro regeneration protocol may contribute significantly to the development of improved red ginger genotypes using contemporary biotechnological tools.