The in vitro genetics of barley (Hordeum vulgare L.): detection and analysis of reciprocal differences for culture response to 2,4-dichlorophenoxyacetic acid

Abstract

The procedures of biometrical genetics have been used to detect and analyse reciprocal differences for the response of immature barley embryos to 2,4-dichlorophenoxyacetic acid in culture. Two genotypes were examined (4082 and R23) which had exhibited large reciprocal differences in culture in previous experiments. The F1, F2 and backcross generations, including full reciprocal families, were produced from these, true-breeding genotypes and evaluated in culture. The experiments confirmed the presence of reciprocal differences. Such differences were subsequently shown to stem from cytoplasmic effects alongside effects traceable to the mother tissue. The implications of these findings for the manipulation of barley genotypes in vitro are discussed.