| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2000: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 1999: ¥2,200,000 (Direct Cost: ¥2,200,000)
|
|---|
| Research Abstract |
In the present study, first, we revealed that a molecular phylogenetic tree based on DNA sequences of plastid matK gene provides much better resolution of major evolutionary relationships of the monocotyledons than a molecular phylogenetic tree based on DNA sequences of plastid rbcL gene. Second, using DNA sequences of both matK and rbcL genes, we constructed the molecular phylogenetic tree that provides the best resolution of major evolutionary relationships of the monocotyledons among molecular phylogenetic trees published until the present time as far as I know. And, we proved that Liliaceae are not monophyletic and can be divided into at least five lineages, i.e., Liliales, Asparagales, Tofieldiaceae, Nartheciaceae, and Petrosavia-group. In the matK + rbcL tree of the monocotyledons, Acorales is diverged as the first branch, followed successively by Alismatales-group (including Tofieldiaceae), Petrosavia-group, Dioscoreales-group (including Nartheciaceae), Liliales, Asparagales, an
… More
d Commelinales-group. And, we established a framework of a new classification of the monocotyledons based on molecular information.
Next, we reexamined taxonomy of the Tofieldiaceae, which are one of the most morphologically primitive monocotyledonous families and are important in considering the ancestral morphology of the monocotyledons. And, we concluded that the Isidrogalvia, which has fully connate carpels, should be transferred from the Tofieldiaceae to Nartheciaceae. After this transfer, the Tofieldiaceae correspond only to plants with almost free carpels, and the morphological primitiveness of the Tofieldiaceae became more definitive. The calyculus, which the Tofieldiaceae and Isidrogalvia share, turned out to have evolved in parallel in the lineages of Tofieldiaceae and Nartheciaceae.
Further, we revealed relationships among families, genera and species of the Convallariaceae (Asparagales) and their allied families, in which the taxonomy was quite controversial and the chromosomal characters are highly diversified, and estimated the direction of evolution of the chromosome numbers and karyotypes. Less
|
