Resistance Against Drechslera teres (Sacc.) Shoem. in Progenies of in vitro Selected Callus Derived Plants of Barley (<i>Hordeum vulgare</i> L.)

Abstract

Abstract Immature embryo derived callus cultures of barley were selected in vitro against a toxin (culture filtrate‐methanol supernatant) produced by Drechslera teres. Both S 1 and S 2 progenies of regenerated plants (selected by toxin application and non‐selected ones) were tested for their toxin tolerance and disease resistance. For this purpose, it was possible to use different culture filtrates and pathogen isolates, produced and maintained at two phytopathological institutes. Twelve out of 26 S 2 progenies examined had a significantly reduced toxin sensitivity in comparison to the donor. Nine of these genotypes also expressed an isolate‐dependent improvement of their disease resistance. At the level of individual plants, 9 progenies showed a correlation between toxm tolerance and resistance against the pathogen. Somaclonal variation in reactions of non‐selected regenerated plants occurred. A mutagen treatment increased the number of toxin tolerant plants within s, progenies, and segregation took place for this trait.