Kuang Liang Huang

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.

Flower colours and pigments in hybrid tuberose (Polianthes)

Abstract The flower pigment constitutions of nine hybrids with pink, reddish purple, purple, orange and yellow flowers obtained from the crossings and back-crossings using Polianthes tuberosa ‘Single’ and ‘Double’ and Polianthes howardii were analysed. Among the parents and hybrids, two white flowered cultivars of P. tuberosa had neither carotenoids nor anthocyanins, one hybrid had only carotenoids, four hybrids had only anthocyanins and an additional other four hybrids along with P. howardii had both carotenoids and anthocyanins in their petals. The main anthocyanidin in the petals of anthocyanin containing flowers is cyanidin with which some hybrids also contained delphinidin. Inducing of the anthocyanins and carotenoids from P. howardii into P. tuberosa can contribute to the extension of the diversity of flower colours in further tuberose breeding.