Isolation of a recessive barley mutant resistant to S-(2-aminoethyl)L-cysteine

S-(2-aminoethyl)L-cysteine (AEC) inhibits the growth of mature barley (Hordeum vulgare L vars. 'Bomi' and 'Maris Mink') embryos grown on sterile medium. This inhibition is relieved by lysine and, to a lesser extent, arginine and ornithine. In order to try and select plants which accumulate lysine, 8200 M2 embryos of sodium azide mutagenised barley were screened for growth in the presence of 0.25 mM AEC. One line, R906 was selected for further characterisation. Progeny of the originally selected plant after selfing were all resistant to AEC. In a reciprocal cross with a sensitive barley the resistant trait was inherited as a single recessive nuclear gene which we designate aec-1.