水稻花粉發育及花藥培養過程中微細構造之觀察

Abstract

新竹糯四號水稻(Oryza sativa L . Cv. Hsinchu 4)之花藥從開始培養至20天止，每隔2天取樣，材料處理後以透式電子顯微鏡、掃描式電子顯微鏡及光學顯微鏡觀察其構造之變化。花藥經培養後，有些花粉能發育成為癒合組織，在這過程中小孢子、花粉壁、花藥壁及癒合組織均發生顯著之轉變。子孢子可以對稱或不對稱之方式進行第一次有絲分裂，有時並可發現核融合之現象。癒合組織內之細胞具分生組織之特性，細胞核大而明顯，細胞質稠密並含澱粉體，且細胞分裂旺盛。小孢子在孢子體分化過程中，細胞質與胞器均未退化。花藥壁細胞在培養期間雖有改變，但不分裂。本研究也同時觀察花粉在植株上之正常發育，並作比較。

Cultured anthers Of rice (Oryza sativa L. cv. Hsinchu 4 ) fixed every 2 days through 20 days of culture Were examined by transmission electron microscopy, scanning electron microscopy and light microscopy。During this period, some microspores developed into callus knowing as androgenesis. Remarkable structural changes associated with this development were observced, including microspores callus, pollen wall and anther wall. First division of microspores was either symmetrical or asymmetrical. Nuclear fusion occurred in early sporophytic development had also been found. The cells of callus turned into meristematic cells containing high density of cytoplasm, conspicuous nuclei and amyloplasts. Regression of cytoplasm and organelles did not happen in microspores of rice during sporophytic differentiation. The cells of anther wall did have some changes in cytoplasm, but they did not become callus. The development in of microspores both in vivo and in vitro were also compared 。