Efficient plant regeneration from root callus tissues of barley (Hordeum vulgare L.)

An efficient method was established for high frequency plant regeneration from 3, 5 and 7-day-old root segments of barley (Hordeum vulgare L.). Compact and white to pale yellow embryogenic callus developed from the cut ends of the root segments on Murashige and Skoog (1962) medium supplemented with 2,4-D (10 to 30.0 mu mol/L), BAP (4.4 mu mol/L), thiamine HCl (2.9 mu mol/L), myo-inositol (110.0 mu mol/L) and casein hydrolysate (0.1%, w/v). Somatic embryogenesis was achieved on MS medium containing low concentration of 2,4-D (5.0 mu mol/L) and BAP (2.2 mu mol/L). Shoot buds regeneration occurred with the transfer of embryogenic calli clumps on MS medium enriched with BAP (17.6 mu mol/L), 2,4-D (2.5 mu mol /L) and thiamine HCl (2.9 mu mol/L). Histological sections through regenerating embryogenic calli revealed shoot bud induction and globular somatic embryos. 3 and 5-day-old root segments showed statistically significant difference for embryogenic callus induction, shoot buds regeneration and mean number of regenerated plantlets in comparison to 7-day-old root segments. Root differentiation occurred on MS medium containing IBA (4.9 mu mol/L). Well rooted plants were transferred to soil where they attained maturity and produce fertile seeds.