LAUSR

Mutagenesis breeding for horticultural crops is valuable not only for creating new cultivars, but also expanding the genetic pool for hybridization. Four Silene species were subjected to ethyl methanesulfonate (EMS) and/or caffeine mutagenesis to obtain valuable ornamental traits and to test the effects of different mutagens and combinations. Species responded differently to the mutagens. Generally, caffeine plus EMS treatments had a greater effect on mutation rate than either treatment applied alone. Caffeine alone was found to enhance seed vigor of S. floscuculi. Caffeine as a plant mutagen should be further investigated to determine the most efficient concentration as well as effects on other plant species, as several desirable mutants were obtained with leaf variegation.