In this study, we compared the occurrence of coloring disorders in mango cultivars with different skin colors under high humidity conditions. The following nine cultivars were used : ‘Amakinboshi’ (skin color: yellow green), ‘Ataulfo’ (yellow), ‘Bailey’s Marvel’ (yellow green), ‘Carrie’ (yellow green), ‘Golden Nugget’ (yellow green), ‘Irwin’ (red), ‘Jubilee’ (red), ‘Mallika’ (yellow) and ‘Tahar’ (red). In addition, the fruit quality of these cultivars was also investigated. The full bloom stage of each cultivar ranged from late February to middle March, and the peak of harvest ranged from late June to late July. High humidity treatment started in late April and continued until the end of harvest. High humidity was maintained during the treatment period, with an average daily maximum relative humidity of 98 %. Coloring disorders (red bruise and mottled skin) occurred in reddish cultivars (‘Irwin’, ‘Jubilee’ and ‘Tahar’), but not in those other than red. In ‘Irwin’ and ‘Jubilee’, the later the harvest time, the greater the degree of coloring disorder. Fruit weight was more than 600 g in ‘Bailey’s Marvel’ and ‘Jubilee’, but less than 400 g in ‘Ataulfo’ and ‘Carrie’. The brix was higher in ‘Amakinboshi’, ‘Ataulfo’, ‘Bailey’s Marvel’, ‘Carrie’, ‘Golden Nugget’ and ‘Mallika’ than that in ‘Irwin’. In conclusion, it was clarified that the occurrence of coloring disorders under high humidity conditions is a physiological one peculiar to reddish cultivars.

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Peucedanum japonicum Thunb. is a perennial plant in the Peucedanum of Seriaceae that is distributed in subtropical to warm temperate regions of East Asia. In Japan, it grows wild in the Okinawa islands and mainland and islands of Kagoshima Prefecture. It is rich in vitamin C, β-carotene, lutein, and polyphenols, and has been reported to contain a variety of antioxidants. The purpose of this study was to investigate its distribution in Kagoshima Prefecture in detail, to clarify native habitat, and elucidate its propagation route. The research sites were coastal areas of Minami-Satsuma City, Koshikijima Islands, Amami Oshima Island, Tanegashima Island, Kikaijima Island, Okinoerabujima Island, and Kakeromajima Island in Kagoshima Prefecture. GPS data were recorded in the native habitats, and the varieties of P. japonicum were categorized on the basis of their morphology. The results showed that the varieties were mainly found in rocky coastal areas and were rarely found in sandy areas. On Koshijima Islands, it was observed on the cliffs about 200 m above sea level. In Setouchi Town, Amami Oshima Island, individual plants similar to P. japonicum var. australe in leaves form and plant stature was observed. In five of the surveyed areas (Minamisatsuma City, Amami Oshima Island, Kamikoshikijima Island, Nakakoshiki jima Island, and Shimokoshikijima Island, in Kagoshima Prefecture), the leaves of pnats were collected, and their DNA was extracted, then they were conducted for cluster analysis. As a result, the phylogenetic trees were classified into three clusters in Minami-Satsuma City, Amami Oshima Island and Koshikijima Islands by the ME, NJ and UPGMA methods.

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In the field of agriculture and rural development, a thorough understanding of rural livelihoods forms the basis of academic and development projects. Livelihood diversity (diversification) has been discussed often in the context of household economy, especially in the developing countries of Asia and Africa. However, methods for evaluating livelihood diversification have not yet been standardized to the point where they can be applied to comparative studies or meta-analyses. Therefore, this study aimed to develop a simple method for measuring the livelihood diversity of rural households in Southeast Asia based on common indices and standardized measures. First, two popular indices were selected: the Structural Livelihood Diversity Index (SLDI) and the Distributive Livelihood Diversity Index (DLDI), which is an inversed Simpson index. Then, to extend the potential application of the SLDI and DLDI, two additional measures were established. The first measure consisted of 12 general categories for classifying livelihood activities that are applicable to rural villages under the different ecological and socioeconomic conditions of the region. The second measure consisted of a scale comprising five grades for classifying ranges in the quantitative data. Finally, a package consisting of the two indices and the two measures could be practically applied to some cases on both the mainland and insular Southeast Asia. The accuracy of the developed method was verified using the Monte Carlo method.

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