• 作者： 鄭炳今; 成游貴; 黃真生
• 作者服務機構： 美國依利諾大學醫學中心解剖學系; 臺灣省畜產試驗所飼料作物系; 臺灣省農業試驗所農藝系
• 中文摘要： 木試驗是以栽培稻（臺中65號）為材料，對水稻花葯表面脊狀角質凸起做一詳細之觀察，
  並試行探討其成因。水稻花葯發育初期，角質層為一均質構造，不具有一般植物角質層所具有的
  網狀構造，此可能表示角質層與細胞壁之結合力薄弱。在初花粉時期，角質層與細胞間開始在某
  些部位分離，隨看花葯發育，角質層逐漸向外隆起，形成脊狀凸起，在脊狀凸起形成時，表皮細
  胞內並不具有任何可能與脊狀凸起形成有關的細胞胞器，因此，脊狀凸起之形成原因，可能由於
  細胞壁收縮或角質擴張所造成的，此種脊狀凸起於花葯成熟時，佈滿整個花葯表皮細胞，而細胞
  與細胞問之脊狀凸起亦相連繫，構成一連鎖網。
  在花粉囊間帶 之細胞無脊狀凸起形成，而此?細胞並不其有發育良好之角質層，但花粉囊
  問帶 則形成小脊狀突起。此種花粉囊在花葯上的幾何結構，可能為花葯開裂佈粉之基本機械因
  素。由於花葯開裂前之失水現象，造成表皮細胞之塌扁變形，而導致花粉囊外周長之變短，周長
  之變短與其下層之內殼細胞間產生一偶力，此偶力作用於花粉囊間帶 及花粉囊間帶 ，而前者為
  結構弱點，故此偶力將花粉囊間帶 拉離葯隔組織，而使花葯開裂。
  2
• 英文摘要： Ridge cuticles can be found on the anthersurfaces of such plants as corn, sorghum, oats,wheat and rice. How these ridges are formedis not clear nor are their ultrastructural featuresknown. In this study, cultivated rice (Oryzasativa L., Taichung 65) anthers were fixed inCheng's fixative and processed for LM, SEMand TEM studies. The cuticlar ridges developat the young-pollen stage as an outfolding ofthe pre-existing cuticle layer. This ridge forma-tion does not occur on the intermicrosporangialstripe 1 (ISM1). TEM and SEM studies indicatethat the ISMIs do not have well developedculticle and possess a very smooth externalsurface; however, the IMS2s develop very lowridges. A homogeneous cuticle layer has beenobserved in the rice anther by electron mic-roscopy. This ultrastructural feature is differentfrom commonly known plant cuticles whichconsist of a homogeneous outer layer and areticular inner layer. The lack of a reticularlayer may suggest that the cuticle layer isloosely attached to the cell wall. At the young-pollen stage, the cuticle layer begins to separatefrom the cell wall in irregular intervals, andthe cuticle begins to fold outward to form ridges.During ridge formation, there is no recognizablecytoplasmic organization which appears to beresponsible for this process. It is proposed thatridge formation may due to the shrinking orshortening of underlying cell wall or to adimensional expension of the cuticle layer, andthat this ridging may represent an initial eventof anther dehisence. The geometrical arrangement of micros-porangia on the anther could provide the mech-anical basis for anther dehiscence. The collapseof the epidermal cell due to the loss of watercauses the shortening of the outer circumferenceof the anther. This, in turn, generates a couple-force with the underlaying endothecium whichis arranged perpendicular to the epidermal cell.Due to the geometrical arrangement of theISMls and IMS2s, the couple-force causses theseparation of IMSIs from underlying connectivetissue.
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