MALTING QUALITY OF BARLEY LINES DERIVED FROM TISSUE-CULTURE

The occurrence of somaclonal (tissue culture-derived) variation in pla nts regenerated from tissue culture will influence the efficiency with which techniques such as genetic transformation can be used in the de velopment of new barley cultivars. To assess the effect of somaclonal variation on malting quality, 12 families of tissue culture-derived li nes from three barley cultivars were analyzed using standard micromalt ing techniques. Each family was derived from a single regenerated plan t that, in turn, was derived from an immature embryo callus culture. F ive to six plants from each family were selected in the R(2) generatio n based on phenotypic similarity to their uncultured parental controls , and advanced to the R(4) and R(5) generations for replicated field t ests. The malting quality of the majority of these lines was altered b y passage through tissue culture, and most alterations were undesirabl e. These results suggest that efforts should be made to delineate in v itro (tissue culture) conditions that are less mutagenic to cultured b arley cells.