桦木科植物花柱适应风媒传粉的特征  

Wind Pollination Characteristics of Styles in Betulaceae

作　　者：朱俊义[1] 张力凡[1] 沈鹏[1] 任保青 梁宇[1] 陈之端[3] 

机构地区：[1]通化师范学院生命科学学院,通化134002 [2]山西太山植物园,太原030025 [3]中国科学院植物研究所系统与进化植物学国家重点实验室,北京100093

出　　处：《植物学报》2014年第5期524-538,共15页Chinese Bulletin of Botany

基　　金：国家自然科学基金(No.31170180;No.31270268);国家重大科学研究计划(No.2014CB954100)

摘　　要：植物体为适应自己的传粉系统,表现出高度的适应特征。风媒花植物为适应风传播花粉,要形成特殊的结构,以扩大接受花粉粒的面积。利用扫描电镜观察了桦木科(B e t u l a c e a e)6属1 8种植物花柱的形态及花粉粒在花柱上的萌发过程,探讨了桦木科植物花柱适应风媒传粉的特征。结果表明,桦木科植物的二心皮(铁木、云南鹅耳枥稀为三心皮)雌蕊具柱状花柱,柱头不发达,花柱表皮细胞长条状,纵向排列紧密。传粉时,花柱表皮细胞能执行柱头的功能,接受花粉粒,为花粉粒萌发提供场所和萌发条件。桦木科植物花柱有2种类型:一种是花柱表皮细胞能形成乳突,花粉管经乳突细胞进入花柱;另一种是花柱表皮细胞不形成乳突,花粉管经过花柱表皮细胞或胞间隙进入花柱。无论花柱表皮细胞是否形成乳突,乳突的形态、大小以及花粉管和乳突的结合方式等在族间、属间、属内种间存在差异。与基部被子植物相比,桦木科植物的花柱呈现适应风媒传粉的进化特征。桦木科植物花柱表皮细胞形成的乳突与基部被子植物柱头乳突功能相同,是桦木科植物风媒传粉的适应策略。Forpollination,plants show a high degree of adaptation.To expand the area to accept pollen,wind-pollinated flowering plants form a special structure to adapt to wind-spread pollen.We investigated the morphology of styles and pollen tube growth on styles(includingstigmas) for 18 species of 6 generain Betulaceae by scanning electronmicro scopy.Betulaceae have two-carpel(orrarelytri-carpelin Ostrya japonica and Carpinus monbeigiana)gynoecia,usually with cylindrical styles and not well-developed stigmas.Styles have elongate epidermalcells,arrange dlongitudina llyandtightly;stylesf unctionasstig matoreceiv ematurepoll engrains and provideasu itabl egermin ationenv ironment.Betulaceae have two typesofstyles:inone,epidermal cell shave bubbleortu bularpapillae,and the pollen tube entersthe style through papilla;intheother,epidermal cell shave nopapillae,and the pollen tube entersthestyle between the epidermal cells.Whether style epidermal cells can for mpapill aeornot,the morphology orsize of papillae and the binding mode of pollenand papilladif fersby tribe,gender andgenus.The style epidermal cells in Betulace aecoul dperform the function of astigma,receiving pollen and providing location sand conditions for poll enger mination.The papillae formed by style epidermal cells in Betulaceae have the same function as in basal angiosperms,an adaptation strategy for plants with wind pollination.

关 键 词：桦木科 花柱 乳突 风媒传粉 

分 类 号：Q944[生物学—植物学]