Kuroshima-mikan (synonym: Shimamikan) (Citrus sp.) is a local citrus grown on islands in Kagoshima Prefecture, Japan, located in temperate and subtropical areas: Nagashima, Koshikijima, Kuroshima, Tanegashima, Yakushima, Amami Oshima, Kakeromajima, and Tokunoshima. In general, all six Kuroshima-mikan accessions collected on different islands showed similar fruit characteristics. Although the fruit characteristics of Kuroshima-mikan and Kishu-mikan ‘Sakurajima-komikan’ (C. kinokuni) were similar, differences were observed in the flavor, titratable acidity, and embryony. The embrony of the former was polyembryony and that of the latter was monoembryony. In the six Kuroshima-mikan accessions, the genotype combinations of 16 cleaved amplified polymorphic sequence (CAPS) markers were identical to each other. Kuroshima-mikan was distinguished from all control accessions and was closely related to the Chinese mandarin Sunki (C. sunki). The genetic differences between Kuroshima-mikan and the Chinese mandarin Kishu-mikan ‘Sakurajima-komikan’ were greater than those between Kuroshima-mikan and the Indian mandarin Cleopatra (C. reshni), the Japanese mandarin ‘Ogimi-kuganii’ (C. depressa), and Tachibana (C. tachibana). Kuroshima-mikan was distant from the sweet and sour orange, citron, and pummelo. The results of the CAPS analysis ruled out a parent-offspring relationship between Kuroshima-mikan and ‘Sakurajima-komikan’.

Changes in leaf characteristics with age and leaf area, shoot biomass and its ratio in each organ and part at the harvest stage (flower bud formation stage) of gebang palms grown in Kupang, East Nusa Tenggara and on Muna Island, Southeast Sulawesi, Indonesia were surveyed. The changes in leaf characteristics were small from the early trunk elogation stage to the flower bud formation stage. The great shoot biomass at the harvest stage of gebang palm was achieved by the long growth period rather than the size of the leaf area. In addition, the ratio of the leaf biomass was small, and that of trunk biomass was extremely high, 90–95%. However, due to the development of the outer peripheral fibrous tissue of the pith, the ratio of the bark biomass, including the peripheral fibrous tissue of the pith in the trunk biomass, became high, and the ratio of pith biomass was 70–80%, which is slightly lower than that of the sago palm and almost the same as that of the sugar palm. Therefore, it was clarified that the high biomass of pith, which is the accumulation part of starch, in the gebang palm was secured by the high biomass at the harvest stage, not by the superior distribution of assimilated products to the pith. Moreover, the starch productivity of the gebang palm was presumed to be superior because of the high pith biomass and high starch percentage in the pith.

To determine the suitable vapor pressure deficit (VPD) for cherimoya pollination, flowers were detached one day before anthesis and hand-pollinated with fresh pollen. Then, the pollinated flowers were incubated under 12 different VPDs for 18 h. Ovary morphogenesis and pollen-tube growth in pistils were anatomically observed using a fluorescence microscope. Pistil malformation associated with shrunken ovaries was observed at higher VPDs. Pollen-tube pathways were partly interrupted in malformed pistils. The percentage of normal flowers was less than 40% at higher VPDs (1.2–2.5 kPa), whereas it sometimes reached to 90% or at least it was more than 50% at lower VPDs (0.2–1.2 kPa). Pollen-tube growth was largely inhibited at higher VPDs. This may be caused by insufficient secretion in pistils due to drought. Embryo sac malfunction might be another cause of incomplete pollen-tube induction. Pollen tubes successfully reached the embryo sac in more than 20% of the observed pistils at lower VPDs (less than 1.0 kPa), suggesting that the optimum VPD for cherimoya pollination was less than 1.0 kPa.

The genus Vigna contains various economically important species such as cowpea and mung bean. The growth of three wild Vigna species—V. vexillata, V. luteola, and V. marina—was examined with cation and anion absorption and translocation as well as compatible solute accumulation, such as sugar and proline concentrations, that are considered to relate to osmoregulation against salt stress with 100 mM NaCl treatment. Vigna plants’ specific characteristics of Na⁺ absorption and translocation of salt-tolerant accessions as Na⁺ excluders or includers became even clearer when the accumulation of Na⁺ content in each part was compared. It was also clarified that the extent of the increase in Cl^- content was larger than that of Na⁺, especially in the root under salt stress, although the growth of Vigna plants was impacted more by the change in Na⁺ than that in Cl^-. Furthermore, the increase in sucrose, glucose, fructose, and proline in the plant body was considered to enable salt-tolerant Vigna plants to retain their physiological functions through osmotic adjustment under salt stress. The extent of increase in each type of sugar and proline was different between the species.

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).