植物学报
植物學報
식물학보
ACTA BOTANICA SINICA
2002年
8期
903-907
,共5页
王印政%李振宇%潘开玉%邹秀红
王印政%李振宇%潘開玉%鄒秀紅
왕인정%리진우%반개옥%추수홍
幼苗发育%子叶%功能进化%科级系统位置%台闽苣苔属%苦苣苔科
幼苗髮育%子葉%功能進化%科級繫統位置%檯閩苣苔屬%苦苣苔科
유묘발육%자협%공능진화%과급계통위치%태민거태속%고거태과
seedling development%cotyledon%functional evolution%familial placement%Titanotrichum%Gesneriaceae
为解决台闽苣苔族(Titanotricheae)这一单种族的科级系统位置,通过扫描电镜观察了台闽苣苔( Titanotrichum oldhamii (Hemsl.) Solereder)植物的种子发芽和幼苗发育过程.随着下胚轴的向下伸长,两个子叶开始不明显的异率生长,其中一片子叶略大于另一片子叶.但两片子叶均正常发育并位于同一高度.当真叶发出后,两片子叶几乎等大,并且两个子叶柄等长.在幼苗生长期间,随着子叶的生长,胚芽也正常萌发出茎的顶芽.顶芽持续进行顶端生长产生交互对生的真叶.这一幼苗生长式样和苦苣苔亚科其他类群的仅一片子叶发育与胚芽被抑制的幼苗生长式样有明显区别.考虑到台闽苣苔植物在总状花序的上部大量簇生无性珠芽,并落地迅速生长出新的植株这一在苦苣苔科中独特的无性繁殖方式及相关性状,台闽苣苔族可能较早地从苦苣苔亚科中分化出来,并在繁殖体的功能进化方面和其他类群发生歧化进而获得独特的无性繁殖方式.台闽苣苔族在系统发育上应该被认为是其他苦苣苔亚科类群的姊妹群,应当提升为亚科等级.
為解決檯閩苣苔族(Titanotricheae)這一單種族的科級繫統位置,通過掃描電鏡觀察瞭檯閩苣苔( Titanotrichum oldhamii (Hemsl.) Solereder)植物的種子髮芽和幼苗髮育過程.隨著下胚軸的嚮下伸長,兩箇子葉開始不明顯的異率生長,其中一片子葉略大于另一片子葉.但兩片子葉均正常髮育併位于同一高度.噹真葉髮齣後,兩片子葉幾乎等大,併且兩箇子葉柄等長.在幼苗生長期間,隨著子葉的生長,胚芽也正常萌髮齣莖的頂芽.頂芽持續進行頂耑生長產生交互對生的真葉.這一幼苗生長式樣和苦苣苔亞科其他類群的僅一片子葉髮育與胚芽被抑製的幼苗生長式樣有明顯區彆.攷慮到檯閩苣苔植物在總狀花序的上部大量簇生無性珠芽,併落地迅速生長齣新的植株這一在苦苣苔科中獨特的無性繁殖方式及相關性狀,檯閩苣苔族可能較早地從苦苣苔亞科中分化齣來,併在繁殖體的功能進化方麵和其他類群髮生歧化進而穫得獨特的無性繁殖方式.檯閩苣苔族在繫統髮育上應該被認為是其他苦苣苔亞科類群的姊妹群,應噹提升為亞科等級.
위해결태민거태족(Titanotricheae)저일단충족적과급계통위치,통과소묘전경관찰료태민거태( Titanotrichum oldhamii (Hemsl.) Solereder)식물적충자발아화유묘발육과정.수착하배축적향하신장,량개자협개시불명현적이솔생장,기중일편자협략대우령일편자협.단량편자협균정상발육병위우동일고도.당진협발출후,량편자협궤호등대,병차량개자협병등장.재유묘생장기간,수착자협적생장,배아야정상맹발출경적정아.정아지속진행정단생장산생교호대생적진협.저일유묘생장식양화고거태아과기타류군적부일편자협발육여배아피억제적유묘생장식양유명현구별.고필도태민거태식물재총상화서적상부대량족생무성주아,병락지신속생장출신적식주저일재고거태과중독특적무성번식방식급상관성상,태민거태족가능교조지종고거태아과중분화출래,병재번식체적공능진화방면화기타류군발생기화진이획득독특적무성번식방식.태민거태족재계통발육상응해피인위시기타고거태아과류군적자매군,응당제승위아과등급.
The seedling development of Titanotrichum oldhamii (Hemsl.) Solereder has been investigated to provide insight into the evolution and systematic position of Titanotrichum . In T. oldhamii, the size differentiation of the two cotyledons begins while the hypocotyl grows. However, both of the two cotyledons develop normally and locate at the same level. Finally, the two cotyledons are almost equal in size. The aerial shoot (including stem and leaves) is produced from the permanent activity of the apical meristem in the plumular bud. Even though the seedling development in Titanotrichum basically conforms to the general growth pattern of the seedling in the Cyrtandroideae, it is remarkably different from that of other Cyrtandroideae. Based on the revealed evidence in seedling development in Titanotrichum and other comparative data, the authors have evaluated the possible evolutionary pathway of Titanotrichum and further discussed the familial placement of this genus.