Expression of the stay-green character introgressed into Lolium temulentum Ceres from a senescence mutant of Festuca pratensis

A mutant allele at the nuclear locus sid confers indefinite greenness on senescing leaves of the pasture grass Festuca pratensis. Via the bridging species Lolium multiflorum and a programme of backcrossing and selfing, the mutant allele (designated sid(y)) was introgressed into Lolium temulentum Ceres. The latter is a fast-growing, annual, inbreeding model grass with many advantages over the slower, perennial, genetically heterogeneous outbreeder F. pratensis. Analyses of photosynthetic pigments, total leaf proteins and individual plastid polypeptide components in senescing attached and detached leaves of yy, yY and YY plants confirmed that the stay-green phenotype of yy F. pratensis had been successfully introduced into the L. temulentum background.