Monographic study of Impatiens drepanophora group

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To clarify the taxonomic status and taxonomy of Impatiens drepanophora and its allied species all the taxa described from Himalaya and other Asian regions were morphologically and genetically studied based on living and herbarium specimens.1. Phylogenetic analyses of genus Impatiens based on chloroplast and nuclear DNA were done for the first time. The combined sequence of rbcL and the spacer between trnL and trnFwere used to generate the first molecular phylogeny of Impatiens. The phylogenetic tree drawn by this analysis revealed the presence of two large monophyletic clades: one consisting only of Himalayan species and the other of species distributed in various areas of the world. The phylogenetic tree is strongly correlated with chromosome numbers; the Himalayan clade has x=7 or 9; the other clade has x=8 or 10. With regard to character evolution, the tree supported evolutionary trends in basic chromosome numbers and inflorescence morphology. Morphological diversification of the lower sepal, which is a significant characters used in the classification at the species level, does not clearly correlate with the tree.2. The specimens collected in Himalaya and other Asian regions were investigated, and dissected flowers to observe the shape and size of sepals and petals.3. The morphology of inflorescences were observed based on the living and herbarium specimens.4. The morphology of the flowers and inflorescences were compared to detect the diversitythe evolutionary trends and reveal the diversity of them.5. All the species described and recorded from China were preliminary revised and described in a volume of `Flora of China' (C. Y. Wu&P. H. Raven, redactors).6. A species of Mt. Kinabalu was described as a new species. The choromosome numbers of this, Impatiens kunabaluensis, and other species known from West Malesia were also published.