禾本科分类和鉴定完整版.pptxVIP

禾本科植物系统与分类简介 禾本科植物系统与分类简介概览禾本科植物的起源 禾本科植物的分类系统 形态术语认识禾本科植物 概 览禾本科是被子植物第四大科；世界700余属，国产226属，占世界总属数的1/3；世界约10000余种，国产约1800种，占世界总种数的1/5-1/6。热带稀树草原、干草原等的重要组成成分，构成了占陆地面积1/3的草地；人类粮食、油料、糖料的重要来源，提供了绝大多数人口赖以生存的谷物。 Morphology of Grass Size of Genera? 390 genera are monotypic orditypic.? 23 genera have about 100 ormore species and contain about ofall grass species.? 10 largest genera concentrat athird of the species, e.g. Agrostis,Aristida, Calamlagrostis, Digitaria,Eragrostis, Festuca, Panicum,Paspalum, Poa and Stipa. 禾本科5个主要亚科的系统发育关系 重绘自Gaut 2002. New Phytol 154: 15-28 Geographical Distribution? The subfamilies and Tribes are distributed across the world in broad latitudinal belts.? Genera is tend to be restricted to a single land mass.? Endemic species are fairly common. Edwards et al. 2010, Science 禾本科植物的起源? 禾本科的起源和早期演化历史：花粉证据：冈瓦纳北部, 起源时间：晚白垩世或古新世（70-55 Ma）大化石证据：花和小穗（早熟禾亚科）北美早始新世（ ca.55 Ma ，Crepet and Feldman, 1991）中新世晚期 芦竹亚科叶（Thomasson, 1984） 中新世晚期 （ca.7-5 Ma）虎尾草亚科 C4 植物:Thomasson et al., 1986Science 233: 876-878 The new oryzeae fossils suggest substantialdiversification within Ehrhartoideae by theLate Cretaceous, pushing back the time oforigin of Poaceae as a whole. The origin of Poaceae was retrieved asBEPAfrican and shade adapted.Grasses dispersed to all continents by approximately 60 million years after their Gondwanan origin in the lateCretaceous.The crown node of the BEP +PACCMAD clade was dated at 57 Mya.PACPACCMAD taxa adapted to open habitats as early as the late Eocene, a date consistent with recent phytolithCfossil data for North America.MAThe BEP clade members adapted to open habitats later than PACCMADDmembers; this was inferred to occur in Eurasia in the Oligocene.C4 photosynthesis first originated inAfrica, at least for Chloridoideae at c.30 Mya. Outgroup 禾本科植物的分类系统? 18世纪Linné (1753)，Species Plantarum，25个禾草的属，如Andropogon, Cenchrus,Panicum, Hordeum, Triticum, 和Phalaris? 19世纪Robert Brown（1810），第一个真正认识到小穗本质，并将其理解为简化的花序分枝的 学者。林奈则认为小穗是一个单独的花。Panicoideae和Festucoid