Michikazu Hiramatsu

Biogeography and origin of Lilium longiflorum and L. formosanum (Liliaceae) endemic to the Ryukyu Archipelago and Taiwan as determined by allozyme diversity

Allozyme diversity on 13 isozyme loci was investigated for two bulbous species, Lilium longiflorum and L. formosanum, endemic to the subtropical archipelago of continental origin located in East Asia. Degrees of allozyme variability and divergence for L. longiflorum were very high for insular endemic species, indicating relatively longtime persistence of the present widespread distribution across many islands in this phenotypically little-changed species. Lilium formosanum exhibited rather lower variability and divergence than did L. longiflorum and was genetically close to the southern peripheral populations of L. longiflorum with 0.978 as its highest genetic identity value. Combined with other biological and insular geohistorical information, our results suggest that L. longiflorum was established around the end of the Pliocene when the current distribution area was still a continuous part of the ancient Asian continent, and L. formosanum was derived from southern populations of L. longiflorum around the late Pleistocene when the mainland of Taiwan was completely separated from the adjacent islands and the main continent. Depauperization of allozyme variability in some L. longiflorum populations was found on islands with lower altitudes. This reflects bottleneck effects after the complete or almost complete submergence of such low islands during the archipelagos development.

Hybridization and asymmetric introgression between Rhododendron eriocarpum and R. indicum on Yakushima Island, southwest Japan.

We examined natural hybridization between two morphologically and ecologically divergent species on Yakushima Island—the light-purple flowered Rhododendron eriocarpum native to seaside habitats and the red flowered R. indicum native to riverside habitats. By investigation of morphological traits and amplified fragment length polymorphisms (AFLP) we found that hybrid individuals morphologically and genetically intermediate between the two species grow mainly in the seaside areas of the island. The degree of morphological and genetic variation was different among the seaside hybrid populations. Although most pollinator species were exclusive to one of the two flower color groups, the halictine bees of Lasioglossum were observed in both the color types. The crucial interspecific incompatibility after pollination has not been previously described. Geographic distance between the populations is likely to be an important primary factor in bringing about natural hybridization and determining the degree of introgression between R. eriocarpum and R. indicum. The fact that hybrids occur mostly in the seaside area on Yakushima Island indicates that asymmetrical introgression occurs from R. indicum to R. eriocarpum. Alternatively, strong habitat-mediated selection from recurrent floods may prevent the hybrids from colonizing riverside habitats.

Aneuploid plants derived from crosses with triploid grapes through immature seed culture and subsequent embryo culture

Through immature seed culture and subsequent embryo culture, aneuploid plants were derived from various crosses among 184 different triploid hybrid grape vines. In self-pollinations of the 184 vines, 0 to 1.6% of flowers produced immature seeds. In 16 reciprocal crosses between diploid and triploid and between tetraploid and triploid grapes, 0 to 23.0% of flowers produced immature seeds. The immature seeds excised 30–50 days after pollination were cultured for three months on Nitsch and Nitsch medium supplemented with L-glutamine, L-serine, L-cysteine and casein hydrolysate. Embryos developed within the cultured immature seeds were subcultured onto germination medium consisting of MS medium with 1 μM BA. Thirty-four of 137 embryos from 458 immature seeds germinated. Five of the 34 embryos grew normally. The five recovered plants were aneuploids with chromosome numbers from 51 to 59. The rates of embryo and plant recovery were different in different crosses with triploid grapes.

Development and Characterization of Microsatellite Markers for Lilium longiflorum (Liliaceae)

Premise of the study: Ten microsatellite primers were developed to obtain information on genetic variation in Lilium longiflorum, a bulbous species showing high intraspecific genetic differentiation. Methods and Results: Of 61 microsatellite loci isolated using the dual suppression PCR technique, 10 loci were effective to characterize and estimate genetic variation in two populations of L. longiflorum. The number of alleles at each locus was different between the populations (averages = 3.2 and 10.3 alleles per locus), and the mean observed heterozygosity values were 0.245 and 0.732. Conclusions: Our results demonstrate that there is significant genetic variation between the populations and that the microsatellite markers developed in this study will be useful tools for the investigation of the genetic structure and mating system of natural L. longiflorum populations.

Molecular cloning and expression of a 9-cis-epoxy carotenoid dioxygenase gene (NCED) and its relationship to dormancy in Lilium longiflorum and L. formosanum

Summary Individuals in northern populations of Lilium longiflorum in the Ryukyu Archipelago between Japan and Taiwan exhibit deep dormancy which is induced by high temperatures in the Summer, while plants of southern ecotypes and L. formosanum show no dormancy. In higher plants, 9-cis-epoxycarotenoid dioxygenase (NCED) is the critical enzyme for the regulation of abscisic acid (ABA) biosynthesis.The relationships between levels of expression of the LlNCED gene (GenBank Accession No. KC357734) and endogenous ABA levels were examined in 1-year-old seedlings of an L. formosanum population domesticated in Fukuoka (FFU) and in two L. longiflorum populations native to Pitouchiao (LPI), Taiwan, or Kikai Jima (LKI), Japan. The deduced amino acid sequences of the NCED proteins shared high identity with NCED proteins in other monocotyledons, and were closely related to enzymes in other members of the class Liliopsida. A high correlation was observed between levels of LlNCED gene expression and ABA concentration. Seedlings from LKI had the highest level of expression of LlNCED in August, while seedlings from FFU had the lowest level. Higher expression of the LlNCED gene in mid-Summer in the dormant population was related to higher endogenous concentrations of ABA. These results provide evidence that the induction of deep dormancy was initiated by the accumulation of ABA in dormant types of L. longiflorum, which was induced by high Summer temperatures.

Sustainable food systems—a health perspective

Malnutrition in all forms, ranging from undernourishment to obesity and associated diet-related diseases, is one of the leading causes of death worldwide, while food systems often have major environmental impacts. Rapid global population growth and increases in demands for food and changes in dietary habits create challenges to provide universal access to healthy food without creating negative environmental, economic, and social impacts. This article discusses opportunities for and challenges to sustainable food systems from a human health perspective by making the case for avoiding the transition to unhealthy less sustainable diets (using India as an exemplar), reducing food waste by changing consumer behaviour (with examples from Japan), and using innovations and new technologies to reduce the environmental impact of healthy food production. The article touches upon two of the challenges to achieving healthy sustainable diets for a global population, i.e., reduction on the yield and nutritional quality of crops (in particular vegetables and fruits) due to climate change; and trade-offs between food production and industrial crops. There is an urgent need to develop and implement policies and practices that provide universal access to healthy food choices for a growing world population, whilst reducing the environmental footprint of the global food system.