Ploidy Variations Observed in the Progeny of Hexaploid Japanese Persimmon (Diospyros kaki) ‘Fujiwaragosho’

Abstract

This study describes ploidy variations observed in plants obtained from immature embryos of hexaploid Japanese persimmon (Diospyros kaki) ‘Fujiwaragosho’. Embryo rescue culture was conducted for 103 embryos excised from seeds in young premature fruit in mid August. All but one embryo were geminated on MS agar medium containing 5 μM zeatin. Flow cytometric measurements of the nuclear DNA content demonstrated that 67 of the 102 plants obtained were hexaploid while the remaining 35 plants were more than hexaploid. Although ploidy levels of the 35 plants appeared to be predominantly nonaploid or dodecaploid, several aneuploid plants seemed to exist. Chromosome counting in root tip cells of the plants obtained also confirmed that there was a ploidy variation in plants obtained by embryo rescue culture. The possible use of ‘Fujiwaragosho’ as a mother plant for the breeding of seedless non-astringent persimmon cultivars is discussed.