Efficient plant regeneration system from seed-derived callus of ravenna grass [Erianthus ravennae (L.) Beauv.]

Abstract

An efficient method of plant regeneration from seed-derived callus was established in ravenna grass [Erianthus ravennae (L.) Beauv.], which is an ornamental tall grass as well as an important biomass crop. For callus induction, mature seeds were cultured on media containing different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) (0.5, 1, 2 and 4 mg l⁻¹) and 6-benzyladenine (BA) (0, 0.1 and 0.2 mg l⁻¹) on callus induction using MS medium (Murashige and Skoog 1962) supplemeted with 1 g l⁻¹ casamino acids, 30 g l⁻¹ maltose and 8 g l⁻¹ agar as a basal medium. The highest callus induction was obtained on medium supplemented with 2 mg l⁻¹ 2,4-D and 0.2 mg l⁻¹ BA, where 96% of explants formed callus. During the subculture of the calli on the same medium for 4 months, 3 types of calli showing different growth rate, color and morphology were differentiated. By using these 3 types of calli, effects of different concentrations of BA or 6-furfurylaminopurine (kinetin) (0, 0.1, 0.5, 1, 2 and 4 mg l⁻¹) and naphthaleneacetic acid (NAA) (0, 0.25, 0.5 and 1 mg l⁻¹) as plant growth regulators on shoot regeneration were evaluated using MS medium with 1 g l⁻¹ casamino acids as a basal medium. The highest frequency of shoot formation was obtained in type A callus, which had white and compact nature, on medium containing 30 g l⁻¹ sucrose, 1 mg l⁻¹ BA and 0.1–0.25 mg l⁻¹ NAA, where 89.3% of the calli formed shoots.