华中五味子(五味子科)雄花和雌花的形态发生  

Ontogeny of Staminate and Carpellate Flowers of Schisandra sphenanthera (Schisandraceae)

作　　者：刘忠[1] 路安民[1] 

机构地区：[1]中国科学院植物研究所系统与进化植物学开放研究实验室,北京100093

出　　处：《Acta Botanica Sinica》1999年第12期1255-1258,共4页Acta Botanica Sinica（植物学报：英文版）

基　　金：国家自然科学基金!资助项目 (No .396 30 0 30 )&&

摘　　要：通过扫描电镜观察了中国特有种华中五味子 (SchisandrasphenantheraRehd .etWils .)雄花和雌花的形态发生过程。雄花 :花被片和雄蕊连续向顶发生 ,未见有雌性结构的分化 ;花药的分化先于花丝 ;雄蕊始终螺旋状排列在柱状花托上。雌花 :花被片和心皮也为 2 /5序列连续地螺旋状向顶发生 ,未见有雄性结构的分化 ;心皮原基近轴面基部边缘的活动不明显 ,心皮为对折型 ;胚珠原基在心皮近轴面上近边缘处发生 ,片状胎座。与北美五味子 (S .glabra (Brickell)Rehd .)相比较 ,认为雄蕊群的演化趋势是 ,花托由长变短而使雄蕊由螺旋状排列变为近轮状排列 ;雄蕊数目减少 ,由不定数到 5 ( 4～ 7)枚。初步分析了不育雄蕊形成的原因以及单性花的性质。提出了心皮原基的形态可分为两种类型。TheontogeneticprocessofthestaminateandcarpellateflowersofSchisandrasphenantheraRehd . etWils.,anendemicspeciestoChina,wasobservedforthefirsttimeunderthescanningelectronmicroscope (SEM) .Inthestaminateflowers ,theperianthunitsandstamenswereinitiatedacropetallyinacontinuous fasionwith 2 / 5spiralphyllotaxis ,whilenofemalestructureswereformed .Anthersweredifferentiatedpriorto thefilamentsformation .Throughoutallthestageswerethestamensarrangedspirallyonacolumniform receptacle .Inthecarpellateflowers,theinitiationsequenceoftheperianthunitsandcarpelsweresimilarto thatofthestaminateflowers .Incontrast,nomalestructureswereformed .Shortlyafterinitiation ,thecarpel primordiabegantheirmarginalgrowthbesidestheapicalgrowthandthenappresseswereformedontheadaxial surfacesoftheprimordia .Howeverthelowermarginsoftheseappresseswereinconspicuous,resultingin conduplicatecarpels .Twoovulesweredevelopedontheinnersurfaceneareitherlateralmarginsofthecarpel, shapinglaminarplacentae .ComparedwithS .glabra (Brickell)Rehd .,arelatedAmericanspecies ,theevo lutionarytrendofphyllotaxisofandroeciaisconsideredthatstamensmaychangefromspiraltoapproximately whorledarrangement,accompanyingwiththechangeofreceptaclefromacolumntoaflattenedshield .Itwas alsosuggestedthatthestamensbeingnumerousanduncertaininnumberbecomecertainanddecreaseinnum berto 5( 4-7) .Sterilestamensareobservedandtheunisexualnatureoftheflowersisdiscussed .Twotypes ofcarpelprimordiaarecategorized ,correspondingtotwotypesofcarpels,namely ,ascidiateandconduplicate carpels,respectively .

关 键 词：华中五味子 花 形态发生 雄花 雌花 

分 类 号：Q949.747.1[生物学—植物学] Q944.58