QUANTITATIVE-ANALYSIS OF GROWTH AND REGENERATION FROM TISSUE-CULTURES OF HORDEUM-VULGARE, H JUBATUM AND THEIR INTERSPECIFIC HYBRID

A quantitative analysis of growth and regeneration was undertaken to identify significant media effects in tissue cultures of Hordeum vulgare (HV), H. jubatum (HJ) and their interspecific hybrid (HV×HJ). Immature ovaries generated the most vigorous and easily regenerated callus of several explanted tissues. After callus formation, cultures adapted one of five distinct types, characterized by differences in tissue consistency, pigmentation, growth rate and regeneration. Different growth rates were observed among subcalli of the same callus type. B5 medium supplemented with sucrose (1%), glucose (1%), kinetin (0.3 mg/l) and gibberellic acid (1 mg/l) maximized the regeneration of shoots and roots from certain callus cultures. Exogenously supplied indole-3-acetic acid (IAA)-amino acid conjugates promoted callus growth and inhibited regeneration more effectively than equivalent concentrations of free IAA, HV, HJ and HV×HJ exhibited similar patterns of media-induced callus growth and regeneration. © 1979.