CHANGES IN ISOZYME PATTERNS ASSOCIATED WITH THE DEVELOPMENT OF CALLI DERIVED FROM MATURE EMBRYO CULTURE OF BARLEY (HORDEUM-VULGARE L)

Twelve varieties of barley (Hordeum vulgare L.) were used for embryo culture. High frequency of plantlet regeneration was observed with the N6 regeneration medium supplemented with 0.5 mg/l 2,4-D and 0.5-1.0 mg/l kinetin. During the culture period, calli could be classified into four morphological types: soft watery calli (WC), compact calli (CC), calli from which only roots were regenerated (RC) and from which only shoots were regenerated (SC). Compact calli with regenerative abilities were formed on the surface of the soft watery calli. It is considered that the compact calli may follow two pathways for plant regeneration through either organogenesis or embryogenesis. Peroxidase, esterase, alcohol dehydrogenase zymograms varied markedly with the different types of calli examined using the 2-rowed variety Haruna Nijo which showed the highest frequency of plantlet regeneration. Among them, alcohol dehydrogenase zymogram analysis seemed to be the most useful approach for selecting regenerative cells in callus cultures or suspension cultures. Peroxidase appeared to be related to shoot and root morphogenesis in the process of callus regeneration, while esterase was related to both organogenic and embryogenic abilities.