Segregation for fruit astringency type in progenies derived from crosses of [formula omitted] constant non-astringent genotypes in oriental persimmon ( Diospyros kaki Thunb.)

Abstract

There are very few early ripening, pollination constant and non-astringent (PCNA) cultivars of oriental persimmon ( Diospyros kaki Thunb.), which are hexaploid, and it has been an important breeding target to develop early ripening PCNA cultivars with no fruit cracking. PCNA is completely recessive to non-PCNA types, and no PCNA offspring have yet resulted from crossings between PCNA and non-PCNA local cultivars of Japanese origin. ‘Nishimurawase’, a non-PCNA cultivar, has been believed to be an F 1 from a cross between PCNA and non-PCNA cultivars. In addition, it is an early ripening leading cultivar in Japan with little fruit cracking that has potential to yield early ripening offspring. When ‘Nishimurawase’ was crossed with six PCNA cultivars and selections, no PCNA offspring occurred among 95 offspring. Two F 1 offspring (‘170-10’ and ‘170-26’) were selected from an ‘Okitsu-25’ ( PCNA)ב Nishimurawase’ cross, and when crossed with PCNA genotypes, they produced 23 and 15%, respectively, PCNA genotypes. These percentages of PCNA offspring were nearly the same as the 15% produced from the backcross (non-PCNA×PCNA)×PCNA, as reported earlier. Thus, ‘Nishimurawase’ has no advantage in getting PCNA offspring than other local non-PCNA cultivars, and it was probably not an F 1 from a cross between PCNA and non-PCNA genotypes.