Abstract
In vitro callus formation by mature embryo explants, and subsequent plant regeneration were investigated using 203 Japanese and introduced varieties of barley (Hordeum vulgare L.). These included 176 six-rowed and 27 two-rowed genotypes. Mature embryos detached from seeds were inoculated on the modified N6 medium containing 2 mg/l 2, 4-dichlorophenoxyacetic acid (2, 4-D). Callus was produced in 193 varieties, although most of the calli were soft, watery, translucent and poor in proliferation. Plants could be regenerated from secondary callus especially with some two-rowed genotypes. The growth of secondary callus was promoted by increasing 2, 4-D concentration to 5 mg/l. Plant regeneration was observed in 14 varieties including 6 six-rowed and 8 two-rowed ones. Some of the varieties used, especially the two-rowed ones: may be useful for developing the mature embryo culture system in barley.
