Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/29273
標題: 仙丹花花芽分化和開花調節
Floral Development and Florweing Regulation of Ixora
作者: 陳麗筠
Chen, Li-Yun
關鍵字: Ixora chinensis;中國仙丹;Ixora duffii ‘King Ixora';flowering;cyme;C/N ratio;大王仙丹;開花;聚繖花序;碳氮率
出版社: 園藝學系
摘要: 
本試驗以6月齡之中國仙丹花單節扦插苗為材料,自1999年2月至2000年4月間,利用掃描式電子顯微鏡技術,分析中國仙丹花之花序及花芽發育過程,觀察其形態上的特徵,以瞭解並確定開花過程中的各個階段。經由田間植株莖頂觀察及調查,確立花序分化、發育各階段的時間及小花開放的順序。花之呼喚(floral evocation)發生於九月初,花之創始(floral initiation)見於九月中旬,而花之分化(floral differentiation)則始於九月底。於顯微鏡下,當看到莖頂明顯隆起,二邊有苞片圍繞,顯示植株已進入生殖生長期。之後,可看到分化的第一級花序軸(primary inflorescence axes),並在一個半月中依序分化第二級、第三級及第四級花序軸(secondary, tertiary, and quaternary inflorescence axes)。只要頂端生長點分化到花序軸的階段,則必定會開花,不會夭折(abortion),此時可視為其開花之不歸點(no return)。之後,萼片、花瓣、雄蕊及雌蕊依序發育完成,而於隔年的一月至三月間開花。經由對其花序分化序列的觀察及小花排列方式之調查,可確知中國仙丹花之花序應是聚繖花序(cymose inflorescence or cyme),而非繖房花序(corymb)。而依據已發育之花序上各小花分化層次(differentiation level, 對於分化階段之量化描述)之調查,得知其與總小花數間為一迴歸關係(y=20.4x2-43.4x,r2=0.898,y代表總小花數,x代表分化層次),並可依之估算一花序之總小花數。

Experiments were conducted on six-month-old Chinese ixora (Ixora chinensis Lam.) from February 1999 to April 2000. Floral development was studied with scanning electron microscopy (SEM) to determine the flowering sequences. Morphological characters were used to clarify the stages of flowering processes. The time of organogenesis and flowering arrangement was established through field observations. Floral evocation occurred in early September, floral initiation occurred in the middle of September and floral differentiation began in late September. A distinctly convex apex with bracts around the shoulder indicated the beginning of reproductive development. Subsequently, primary inflorescence axes were observed and differentiated into secondary, tertiary, and quaternary inflorescence axes consecutively in about one and a half months. Once the terminal apex reached the inflorescence bud stage, it would flower without abortion, and this may be assessed as ‘no return'. The sepals, petals, stamens, and pistil were well developed thereafter and anthesis was achieved in January through March in the following year. The observation of floral differentiation sequences and investigation of floret arrangement made it certain that Chinese ixora had cymose inflorescence (cyme), but not corymb. A quadratic equation was established to predict floret number from the differentiation level (a quantitative description of differentiation stage) of a developed inflorescence.
URI: http://hdl.handle.net/11455/29273
Appears in Collections:園藝學系

Show full item record
 

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.