Development of a somatic embryogenesis protocol for tea (Camellia sinensis O. Kuntze) from leaf calli

Abstract

Somatic embryogenesis is an efficient regeneration system with high genetic integrity which useful in the crop improvement. The present study was conducted with the objective of developing a viable somatic embryogenic protocol for leaf calli of tea. Leaf segments of 3 rd leaves of TRI2043 and TRI2024 cultivars were used to produce calli and for induction of somatic embryos 2 nd and 3 rd subcultures were selected. Calli were inoculated in MS media with (i) 2 mgl -1 Benzyl amino purine + 3 mgl -1 Naphthol acetic acid; and (ii) 2 mgl -1 Benzyl amino purine + 3.5 mgl -1 Naphthol acetic acid growth regulator combinations. The greatest amount of embryogenic callus proliferation in both cultivars were achieved from 3 rd subculture using 2 mgl -1 Benzyl amino purine + 3.5 mgl -1 Naphthol acetic acid medium. Compact and friable callus was observed in all culture bottles 3 weeks after culturing and friable calli was reported as the best for the induction of somatic embryos. Somatic embryoids were observed in 2 mgl -1 Benzyl amino purine + 3 mgl -1 Naphthol acetic acid of TRI2043. Significantly highest relative growth rate (92.21%) was observed from leaf callus in 2 mgl -1 Benzyl amino purine + 3.5 mgl -1 Naphthol acetic acid of TRI2024 when using 2 nd subculture (mean value 83.89%). Second subculture of leaf callus in MS medium with 2 mgl -1 benzyl amino purine + 3 mgl -1 naphthol acetic acid is better to induce somatic embryos.