The Morphological and Genetic Characteristics of Local Citrus Grown on the Ryukyu Islands, Japan

Abstract

The origin and intraspecific diversity/uniformity of major local citrus, grown on the Ryukyu Islands, were studied by investigating the fruit characteristics and cleaved amplified polymorphic sequence (CAPS) analysis. The intraspecific diversity of Kunenbo (Citrus nobilis), Kabuchii (C. keraji), Oto (C. oto), Tarogayo (C. tarogayo), and Shiikuu (C. sp.) was not noted in any of the 16 CAPS genotype combinations. In general, these accessions belonged to the same species possessing similar fruit characteristics, especially fruit weight, skin and flesh color, and flavor, although slight differences were noted on the fruit surface, in the titratable acidity, and so on. On the other hand, four Shiikuwasha (C. depressa) accessions showed characteristic CAPS genotype combinations. On the basis of these combinations, parent-offspring relationships of the local citrus were estimated as follows: Kabuchii, Oto, and Tarogayo were offsprings of Kunenbo and Shiikuwasha, Keraji (C. keraji) was that of Kunenbo and Kabuchii, and Rokugatsumikan (C. rokugatsu) and Shiikuu were those of Shiikuwasha and Sour Orange (C. aurantium).