RFLP analysis reveals the genealogical relation of novel Japanese persimmon ‘Saijo’

Abstract

‘Saijo’ Japanese persimmon (Diospyros kaki Thumb.) is one of the most popular and commercially important fruit cultivars in Japan. In 2000, origin-unknown ‘Saijo’-like cultivar was found at the Shimane farm and named as ‘M-3’. Although it has similar morphological and physiological characteristics with ‘Saijo’ cultivars, its fruit size is apparently bigger than ‘Saijo’ making them an attractive candidate as novel valuable fruit for farm household. In this study, to elucidate the genealogical relationship of ‘M-3’, we conducted the restriction fragment length polymorphism (RFLP) analysis using genomic DNA of Japanese persimmon (‘Saijo’ lines, pollinizers, and other cultivars that bloom a male flower) detected by cDNA probes involved in genes coding persimmon fruit ripening: 1-aminocyclopropane-1-carboxylate synthase 1 (ACCS-1), ACC oxidase 1 (ACCO-1), and polygalacturonase (PG-9). We demonstrated that ‘M-3’ line shares several RFLPs specific to ‘Saijo’ lines, pollinizers, and other cultivars. We found that morphological features of fruit and leaf in ‘M-3’ resembled that of ‘Saijo’ and pollinizer lines. These results strongly suggest that ‘M-3’ is likely the seedlings crossbred by ‘Saijo’ and pollinizer cultivars. Our findings provide first insight of genealogical origins of valuable newly identified persimmon cultivar and an important suggestion to establish a new valuable ‘Saijo’ cultivar by cross breeding with pollinizer lines.