披堿草屬(Elymusspp.)是禾本科(Gramineae)小麥族(Triticeae)重要的一個屬，主要分布在歐亞大陸和北美洲北部。其垂直分布從海拔幾米的海灘一直到海拔5200m以上的喜馬拉雅山區。披堿草屬植物的多數物種為草原和草甸的重要組成成分，許多種類是飼用價值較高的優良牧草。
基本資料
屬中文名：披堿草屬
屬拼音名：pijiancaoshu
屬拉丁名：糙頭細銀漢魚
中國植物志：09(3):6
簡介
披堿草屬Elymus牧草分布廣泛，種類繁多，廣義的披堿草屬包括近150個種，而在我國，則比較接受狹義披堿草屬的概念，即有12余種。披堿草屬牧草為中生-旱中生多年生優良牧草，是草原和草甸的重要組成部分，飼用價值極高。該屬是禾本科小麥族中非常重要的一個類群，它具有麥類作物所缺乏的抗病、抗蟲、抗旱、耐鹽等優良抗逆基因，是現代麥類育種的重要種質資源。
所有物種
肥披堿草
披堿草
披堿草(原變種)
披堿草屬
青紫披堿草
圓柱披堿草
披堿草屬(Elymus L．)植物遺傳多樣性研究
以我國9種披堿草屬(Elymus?L．)的40個居群為材料，采用形態學、等位酶和微衛星3種標記對28個形態特征、7個等位酶位點和l1對SSR引物進行遺傳多樣性分析。結果表明：不同居群的披堿草間形態差異顯著；不同種、居群和形態特征變異規律也有所不同。旗葉與穗基部長度、生長速度(幼苗一分蘗)、小穗柄、植株絨毛分級在種內變異較大，而穗的形狀、穗節數、株高和內的變化較為穩定。聚類分析結果表明：披堿草(E．dahuricus?Turcz．)、圓柱披堿草(E．cylindri—CUS(Franch．)本田技研工業)、紫芒披(E．purpuraristatus?C．P．Wang?et?H．L．Yang)變異很大，垂穗披堿草(E．nutans?Griseb?L．)和老芒麥(E．sibiricus?Linn．)的居群按種歸類比較清晰等位酶分析結果表明，在4O個居群材料中7個位點發現了22個等位基因。在屬的水平上多態性位點百分數為87．5?，居群內平均多樣性指數(Hs)為0．0830，居群間平均多樣性指數(Dst)為0．2149，所有多態性位點的遺傳分化系數(Gst)為0．7213。在該屬中，遺傳多樣性(HP)和Shannon’S信息指數(He一0．2974；I：0．4565)最大水平上反應了披堿草居群之間的變異。在種的水平上遺傳多樣性和Shannon’S信息指數分別為0．0800~0．2528和0．
1173～0．3769，而居群內二者分別在0．016O～0．1680和0．0250~0．2433范圍內。在屬內，遺傳分化的分配量依次為種間(38．9?)、種內居群間(33．2?)和居群內個體之間(29．8?)。居群之間基因流(Nm)很低，為0．1932。屬于同一種的居群基本能聚類在一起，同時和地域之間亦有明顯的關系。9種披堿草屬植物雖然不是按照穗的形狀(披堿草組)(Sect．Turczaninovia(Nevski)Tzve1．)和老芒麥組(Sect．Elymus))分為兩組，但屬于披堿草組和老芒麥組內的披堿草關系親近。以垂穗披堿草為例，海拔是影響遺傳差異最重要的因素，其次是地理位置(緯度和經度)。l1個多態性微衛星位點發現有1～8個等位基因，共檢測出38個等位變異，平均3．5個等位變異。來自于披堿草的微衛星引物平均4．5個，而來自于小麥的2．2個，披堿草的特異SSR引物在反應遺傳多樣性方面具有更好的作用和效果。位點ECGA22、ECGA114、EAGA51和WMS43遺傳變異信息含量比較高，對于構建披堿草高密度的微衛星種(品種)指紋是很好的選擇。種內和種間的遺傳多樣性變異結構，多個引物具有很好的一致性，大多數基因多樣性存在于種內，占總變異的75．74％。無論等位酶還是微衛星標記，在青藏高原地區都擁有遺傳豐富的披堿草資源。在披堿草種的多樣性指數變化也很大，基因多樣性和Shannon’S信息指數變化范圍分別在0．1622～0．3619和0．2248~0．5318。相似性和聚類分析結果顯示，對居群水平大致可按種來進行劃分。SSR標記對不同披堿草居群的聚類和材料間的親緣關系和地域分布有較好的一致性。披堿草的9個種并沒有分成幾個明顯的組，而以老芒麥和青海披堿草(E．geminatus?L．)最近，其次是披堿草和紫芒披堿草親緣關系，垂穗披堿草和短芒披堿草(E．breviaristatus(Keng)Keng?F．)也相對較近。地理位置(緯度和經度)是影響垂穗披堿草居群微衛星遺傳差異最重要的因素，其次是海拔。
Study?of?Genetic?Diversity?of?糙頭細銀漢魚?物種
Candidate：YAN?Xue—bing?Advisors：ZHOU?H?e，W?AN?G?Kun (1．Grassland?Institute?of?China?Agriculture?University，Beijing?100094，China； 2．Zhengzhou?College?of?動物界?Husbandry，Zhengzhou，Henan?Province?450008，China) The?genetic?diversities?of?40?populations?of?9?Elymus?物種?from?China?were?determ?ined，?using morphology，allozyme?and?microsatellite?markers?for?28?morphological?traits，seven?allozyme?loci?and?eleven pairs?of?microsatellite?primers．?M?orphological?traits?differed?greatly?among?populations?and?variation?trends also?deviated?within?物種?and?populations．?The?distance?between?the?flag?leaf?and?the?spike?of?a?plant 。the growth?rate?during?the?seedling?to?the?tillering?stage，the?rachilla?and?the?plant?villus?grade?varied?species?from species'though?the?spike?shape，the?spike?pitch?number，the?plant?height，and?the?palea?changed?unvaryingly． Dendrogram?of?relationships?showed?that，though?E．?dahuricus?Turcz．，E．cyli?d，-ic?(Franch．)本田技研工業，and E·purpurari, status?C．P．W?ang?et?H．?L．?Yang?varied?to?a?great?extent，populations?of?E．?t日?Griseb．L．．and?E．長尾朱雀?Linn．?clearly?clustered?together?within?the?物種． A?llozym?e?數據?indicated?that，?7?allozyme?loci?were?encoded?by?22?alleles?across?40?populations ．?The polym?Orphic?loci?percentage?was?87．5?at?genus?leve1．M?ean?of?diversity?index?were?0 ．?0830?within?populations 【Hs)and?0．2149?among?populations?(Dst)．Coefficient?of?genetic?variation?across?all?polymorphic?loci?was 0．7213．Genetic?diversity(H?e)and?Shannon’s?information?index?(?)had?the?biggest?variation?values(H?一0 ．2974；一0·4565)among?populations?of?Elymus?genus，ranging?from?0．?0800?to?0．2528?and?0．1?173?to?0．3769?at 物種?level，from?0．01?60?to?0．1?680?and?0．0250?to?0 ．?2433?within?populations，respectively．of?the?total genetic?variation?of?Elym?us?genus，?38．9?existed?among?species，?33．?2％?amidst?populations?within?the 物種'and?29·8?am?id?individuals?within?a?種群．?Gene?flow?among?the?populations?was?sluggish．a mere?0·1932．Populations?belonging?to?the?same?species?norm?ally?clustered?together，and?the?dendrogram?was obviously?related?to?the?geographical?origins．?Though?9?糙頭細銀漢魚?species?were?not?divided?by?spike?morphology into?two?groups：Sect．Turczaninovia?(Nevski)Tzve1．，and?Sect．?Ety，，2?，all?the?E?，，2?物種?in?the?two Sects·showed?close?relationship．Take?E．nutans?Griseb ．?L．for?an?instance，elevation?was?the?most?imDortant factor?influencing?the?plant’s?genetic?difference，while?the?geographical?site(1atitude?and?longitude)played?only a?secondary?role． M?icrosatellite?數據?indicated?that?there?were?1～?8?alleles?in?the?ll?polym?orphic?SSR?loci ，and?38?multiDle alleles，were?detected，averaging?3．5?m?ultiple?alleles．?M?icrosattelite?primers?developed?from?E／y?“?sDecies averaged?4·5?alleles，higher?than?that?of?wheat?of?an?average?of?2 ．?2，indicating?that?m?icrosatellite?primers developed?from?Elymus?物種?functioned?better?in?determining?its?genetic?diversity ．?Loci?ECGA22、ECGA?1?1?4、 EAGA5?1?and?W?M?S43?transferred?more?inform?ation?on?the?genetic?variation ，?helping?to?the?construction?of fingerprint?of?Elymus?物種．?Primers?consistently?indicated?that?75 ．?74?of?the?variation?existed?am?ong populations?within?the?species．?Tibet?plateau?was?genetically?resourceful?of?E?，2?species?based?on?bo ．thallozyme?and?SSR?m?arkers．Gene?diversity?and?Shannon’s?inform?ation?index?at?species?level?varied greatly?from 0·1622?to?0·3619?and?0．2248?to?0．5318，?respectively ．?Similarity?and?dendrogram?of?clustering?among populations?showed?consistence?with?their?物種?and?geographical?origins．?Nine?E?species?were?not clearly?divided?into?different?groups，though?E ．?長尾朱雀?and?E．gemi?at?related?most?closely，E．?d日h?，-ic and?E·pu?uraristatus?came?next．?So?were?E．nutans?and?E ．?breviaristatus?Geographical?site?(1atitude?and longitude)was?the?most?Im?portant?factor?influencing?the?genetic?difference．?Elevation?came?next?.
參考資料 >
維普.www.cqvip.com.2011-04-22