Early Phenotypic Mutation Results Induced by Ethyl Methyl Sulfonate (EMS) On Species of Penstemon

With recent concern for preserving natural resources, use of drought-tolerant ornamentals may become a valuable method of lowering water usage for homeowners.  The mostly herbaceous perennial Penstemon genus offers drought-tolerance, some level of acceptance in urban landscape and an enormous amount of genetic diversity.  With around 280 different species, Penstemon is among the largest genera of herbaceous perennials native to North America.  Chemical mutagenesis with EMS has been used to induce novel phenotypes in a vast number of crops both agronomic and ornamental.  This mutagen may prove to be a valuable tool in helping to further domesticate Penstemon for use in urban landscaping.  The scope of this research is to identify the phenotypic effects of EMS on several different species of Penstemon.  In Preliminary tests, we have treated Penstemon strictus with concentrations ranging from 0.025% to 3% EMS.  These concentrations have already shown a wide array of mutations in the juvenile vegetative growth.  Among the surviving plants treated with 0.675% EMS, common mutations include: dwarfing (32%), fused leaves (11%), and variegation in the leaf tissue (1%).  Since Penstemon are often clonally propagated, these induced mutations, along with the natural beauty and diversity of Penstemon, may produce superior cultivars which are economically beneficial and environmentally friendly.