High Frequency Plant Regenerartion from Immature Embryos of an Elite Barley Cultivar (Hordeum vulgare L.cv) Baegdong

Abstract

An efficient plant regeneration system was developed for Hordeum vulgare L. cv Baegdong - an important high yielding Korean cultivar. This cultivar is resistant to Fusarium and a few other fungi but susceptible to Barley Yellow Mosaic Virus (BaYMV) and Barley Mild Mosaic Virus (BaMMV). The protocol was based on a series of experiments involving the sizes of immature embryos and the culture media. The embryo size is found to be critical for the establishment of callus. Embryos of 1.6-2.0 mm size showed the highest ability to produce callus capable of regenerating green plants. The auxins picloram and dicamba proved effective in inducing callus from immature embryos. 2.5 mg L 1 dicamba and 4.0 mg L"1 picloram in Murashige and Skoog (MS) medium was optimum for the induction of primary callus. The induced primary callus was loose and friable which ultimately developed into creamy white and compact callus after transferring into the fresh medium. Multiple shoots were induced in the ViMS medium supplemented with 6.0 g L"1 maltose, 20.0 g L"1 sorbitol, 0.5 mg L"1 2, 4-D and 1.0 mg L 1 kinetin and the rate was 6.5 shoots per embryo. Regenerated plants were hardy and developed roots rapidly in the medium containing 0.2 mg L"1 Indolebutyric acid (IBA). This efficient plant regeneration system provides a foundation for generating transgenic plants of this important barley cultivar.