Induced mutants in st augustine grass stenotaphrum secundatum cultivar floratam
Powell, J.B.; Toler, R.W.
Crop Science 20(5): 644-646
The breeding improvement of St. Augustinegrass [S. secundatum (Walt.) Ktze.] is slowed by poor seed set, weak seedlings and triploidy. New methods are sought to improve disease resistance and winterhardiness for cultivation of this warm-season grass at the northern limits of the warm-season growing areas of the USA. Mutation induction with .gamma.-ray treatments of vegetatively propagated parental material offers a possibility of improvement. Stolons of Floratam St. Augustinegrass were irradiated with various dosages of 4.5-7.0 krad. Emerging single-plant propagules were separated from the parental vegetative bud material. Propagules set into the field were evaluated for mutation induction. The 14 mutants ranged from dwarfs to very fine leaf types. Color changes were also noted in the mutants. Genes already present in 'Floratam' for resistance to the St. Augustine Decline Stain of Panicum Mosaic Virus were not modified in the mutants. Developing improved cultivars with mutation breeding procedures could be a major step forward in breeding this species.