New Mutants of Perennial Portulaca grandiflora Through Gamma Radiation

Abstract

Stem cuttings of two perennial Portulaca grandiflora varieties, “Double Orange” and “Double Pink” were gamma irradiated with the doses of 0, 10, 20 and 40 gray. Variations in phenotypic characters of flower color, form and size were noticed. Three characters could be maintained by vegetative
propagation and developed into new mutant varieties. The first mutant, “Chompoo Praparat”, was obtained from irradiated treatments of both Double Orange and Double Pink varieties. The second mutant, “Pattik”, was obtained from all gamma irradiation treatments of Double Orange variety only. The third mutant, “Som Arunee”, was obtained from 40 gray treatment of Double Orange variety. The flower colors of Chompoo Praparat and Pattik are pink (Red Purple Group # 73 A–B) and Orange (Red Group # 40 B–C) as classified by the Royal Horticulture Society color chart respectively. Both have single form of petal (five petals). Som Arunee has double form of petals with deep orange flower color (Red Group # 41 A–B). These mutants do not differ in other characters from the original varieties except the flower color and form.