Ray-Floret Based Rapid Propagation and Detection of Somatic Variation in Selected Mutant Chrysanthemum Individuals

Abstract

Chrysanthemum (Dendranthema × grandiflora Tzvelev) is an attractive plant species that responds well to mutation breeding research conducted worldwide. The isolation and propagation of mutant individuals are very important for detecting mutations in in vitro cultures. Using in vitro cultures, it is easy to isolate solid mutants. In this study, the homogeneous reproductive capacity of selected mutant individuals after irradiation was examined using ray floret cultures at the M1V1 stage, based on various flower colors and architectures. The explant materials were obtained from selected mutant plants with yellow, dark red, orange, and spoon-shaped ray florets cultivated in full bloom. After the determination of an effective sterilization method, the ray florets were cultured in Murashige and Skoog's (MS) media, which contained 0.5 mg L-1 1-Naphthalaneacetic acid (NAA) and 2.0 mg L-1 6-Benzylaminopurine (BAP). The average rate of plantlet regeneration varied depending on the genotype; mutants with yellow-colored flowers generated 0.6 plantlets per explant, those with orange-colored flowers (1.11), those with dark red-colored flowers (1.16), and those with spoon-shaped flowers (2.71). After plant regeneration, plantlets were cultured in a hormone-free MS nutrient medium to ensure full-rooted plant development. The findings of this study showed that in vitro ray floret culture could be used to swiftly and successfully carry out vegetative reproduction of pot-type Brandevil mutants, which are more susceptible to in vivo cutting propagation than pot-type Chrysanthemum cultivars. In the propagating material, there were obtained four differently colored somaclonal plants, eleven partial somaclonal plants with incurved-type ray florets, eight somaclonal plants with spatulate-type florets, one somaclonal plant with semi-double-type flower heads, two somaclonal plants with pointed and reflexing ray florets.