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Ferns and gymnosperms is between bryophytes transition between taxa, it is the first to appear vascular plants, ferns therefore study the occurrence and evolution of systems is extremely important. Polypodiaceae plants are ferns evolved in the last one, representing the most evolved end ferns. In this paper, spore morphology, gametophyte development and molecular phylogeny three aspects of Polypodiaceae plant phylogenetic relationships are discussed: ① using scanning electron microscopy of the domestic Polypodiaceae (Polypodiaceae) 19 are 54 kinds of a variant of a variant and foreign producers Polypodiaceae a 6 species of spores was observed. The results showed that: the single spore plants cracks, bilaterally symmetrical, oval in polar view, equatorial view of kidney-shaped or bean-shaped, wall thick, smooth or warty formed, corrugated or irregular lumps ornamentation, the peripheral wall is thinner, with a warty, granular ornamentation or smooth with appendages. Spore surface ornamentation can be divided into six types: warty ornamentation, tumor-like ornamentation, granular ornamentation, corrugated decoration, ornamentation and smooth with irregular blocky appendages type. ② the domestic Polypodiaceae 11 genera and 13 species and one variety of gametophyte development was observed. The results showed that: imbibed spores germinate, sprout newborn Rhizoids generally the first, in the direction perpendicular to the primary rhizoid produce original cell, type of spore germination Vittaria type; filaments 2 to 12 cells, filamentous cells straight barrel, barrel-shaped or oval barrel. Filamentous apex cells divide to form after two oblique wedge tip cells or filaments 3 to 5 cells forming the wedge tip cells. Sheet body is the tongue-shaped, spoon-shaped or obovate. Most species prothallium stage began trichomes, prothallium developmental manner Adiantum-type or Drynaria type. Mature prothallium is bilaterally symmetrical heart-shaped, midrib obvious. Slightly larger than normal prothallium horizontal axis. Wings on the extension, abduction or inward staggered, rhizoids sometimes with the diaphragm. Archegonial neck cylindrical, slightly curved base of the prothallus. Archegonial neck four cells, neck parietal cells of 4 to 7 layers. Mature archegonial top four lobed; sperm is grown in the base or bisexual male gametophyte gametophyte surface, sperm is spherical or funnel-shaped. Cover cell round, cover cell disruption or the formation of holes releasing sperm; single cell papilloma trichomes are located in prothallium edge, a few growing on the surface; multicellular branched trichomes grown in the original leaf surface, multi-distribution In meristem below archegonial associated with. ③ on Polypodiaceae plant 10 genera and 17 species and one variety of rbcL and rps4-trnS gene sequence was determined, and after finishing sequence assembly software, combined with NCBI 13 genera and 35 kinds upload and rps4-trnS rbcL gene sequence, using ClustalX1.83 Software associated with global operations (Complete Alignment), multiple sequence alignment of the order. Applications adjacent tree (Neighbor joining, NJ) and maximum parsimony (Maximum parsimony, MP) and maximum likelihood method (Maximum likelihood method, ML) by using a phylogenetic analysis software PHYLIP package (Version3.66) constructing phylogenetic trees. Species under the subfamily taxa class together with the classification system consistent with the division of the subfamily, Polypodiaceae may have four different evolutionary routes, in addition to an evolution stone Wei Yake this route may be a monophyletic taxa, the The remaining three evolutionary routes are interconnected, and its relationship with the related families were discussed.
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