Studies On Phylogeny Of Athyriaceae

Athyriaceae is a large and complex taxon in ferns. It contains about 20 genera, including more than 500 species. The phytogeny of the Athyriaceae and the phylogenetic relation among genera are confused since last half hcentury. At present there are two viewpoints about its phylogeny, 1) A system representative of Ching's(1978), it is recognized as a family. 2) A system representative of Kramer & Kato (1990), it is recognized as a subfamily to Dryopteridaceae. Next, the difference between two systems is the range of genera. For example, the view of Kato and Sano, Deparia include five genera of Ching's system: Dryoathyrium,Lunathyrium, Athyriopsis, Diplazium, Dictyodroma.Based on recent molecular phylogenetic analyses using nucleotide sequences of the encoding the large subunit of ribulose 1,5-bisphyosphate carboxylase/oxygenase (rbcL), Hypodematium should be not included in the Athyriaceae, it has closely related to Dryopteridaceae. On the other hand, Athyriaceae, Thelypteridaceae, Blechnaceae, Onocleaceae and Woodisaceae form a large clade, So it may explain that Tryon & Tryon (1982) and Kramer & Kato(1990) putting it forward as Dryopteriaceae s. 1. is unreliable.So, in this paper we follow (Tomus 3(2))(Ching's concept for Athyriaceae in 1978 was modified), Spore morphology and molecular of Athyriaceae was investigated. At the bases of these studies combining the researching informations of predeceesors, the texonmic position of the genera and dividing about subfamily in Athyriaceae were analyzed. I . Spore morphyologySpore morphology of 43 species in Athyriaceae from China was investigated under light microscope(LM) and scanning electron microscope(SEM). The 43 species include 14 species in the genus Dryoathyrium and Lunathyrium ningshenense, 17 species, 3 varieties and 1 hybrid in the genus Lunathyrium, 11 species and 1 variety in the genus Athyriopsis.The spores are monolete, bilaterally symmetry, elliptic in polar view, and semiorbicular or reniform in equatorial view. According to the surface ornamentation of the perine, the spores in the three genera can be divided into three types. Type I is characterized by having lophate processes on the perine which are connected and reticulateor ornate. 3 species in Dryoathyriwn, 4 species and 1 variety in Lunathyrium have this type of spores. Type II is characterized by having curved-lobate , lobate or tuberculate processes on the perine. 8 species in Dryoathyrium, 12 species, 2 varieties and 1 hybrid in Lunathyrium, 3 species in Athyriopsis have this type of spores. Type III is characterized by having spine-like or irregularly baculate processes on the perine. 3 species in Dryoathyrium., 1 species in Lunathyrium, 8 species and 1 variety in Athyriopsis have this type of spores.The surface ornamentation of spores is of important value in the taxonomy of three genera. The study results support the treatment of reducing Lunathyrium ningshenense to the synonymy of D. coreanum. They reveal that Dryoathyrium erecta should be Athyriopsis erecta (similar to the outcome of molecular tree). The studies find the spore morphology of D. stenopteron (Bak.) Ching is not spine-like or irregularly baculate processes in , should be lobate or curved-lobate processes on the perine.II. Molecular phylogenyIn this paper, Nucleotide sequences of the chloroplast gene trnL-f region was investigated first in the ferns, the PCR primers were chosen. In the test, 34 species in Athyriaceae and 3 outgroup taxa were determined trriL-F region sequences.The length of the trriL-F region sequence of the Athyriaceae is between 816 bp and 932 bp. The nucleotide sequences were aligned with about forty insertions or deletions. The data matrix for the 37 taxon contained 553 variable sites (57.6%), of which 336 were phylogenetically informative.The phylogenetic relationships were inferred using the Neighbor-joining and Maximum-parsimony methods. In MP method, the heuristic search generated two single most pa...