多數開花植物經由雙重受精行有性生殖，而後產生種子繁衍後代。然而自然界有些物種是以無融合生殖方式繁衍後代，即無性產生種子。無融合生殖能迅速穩定雜種優勢並降低雜交種子的生產成本，可望在21世紀應用無融合生殖於農業和經濟作物改良。在進行無融合生殖之育種及分子層次之各項研究前，篩選無融合生殖物種為首要工作。

本研究利用細胞學透明化觀察法、組織化學切片觀察法與流式細胞種子篩選法篩檢禾本科黍亞科黍族七種不同植物之生殖方式，建立黍族有性生殖與無融合生殖性狀之模式與篩選方法。結果顯示紫果馬唐、圓果雀稗以及百喜草具有蓼型胚囊，經雙重受精形成胚及胚乳，屬有性生殖。大黍、牧地狼尾草、紅毛草以及蒺藜草屬無融合生殖。其中大黍、牧地狼尾草與紅毛草為典型未減數四核黍型胚囊，具有多胚囊現象，胚係由孤雌生殖得來，胚乳則由假受精產生，屬無融合生殖之無孢子生殖。另外，蒺藜草則具有未減數八核山柳菊型胚囊，胚係由孤雌生殖得來，胚乳則自發性產生，屬無融合生殖之無孢子生殖。

由上述可知，利用細胞學觀察法篩檢黍族無融合生殖性狀，以往主要以四核無反足細胞胚囊或多胚囊為主要辨別特徵，但本研究發現蒺藜草為例外之情形，所以在篩選無融合生殖時，除形態特徵外，仍需配合流式細胞種子篩選法。

Most flowering plants reproduce sexually by seeds via double fertilization. However, some plants reproduce asexually by apomixis, a natural way of cloning through seeds. In the crop breeding field, apomixis can fix the genotype of a superior plant and would enable a significant reduction in the cost of hybrid seed production. Therefore, the application of apomixis also holds great promise as an essential tool for sustainable agricultural production and economic crops improvement in the 21 century. In order to research on apomixis at the breeding and molecular levels, screening apomictic plants would be the primary work in advance.
Different reproduction modes of seven species belonging to Paniceae were comparatively studied by histological embryo sac examination and flow cytometry seeds screening. We find that these combined methods are efficient to discriminate apomixis from sexual reproduction. This research indicated that the embryo sacs of Digitaria violascens, Paspalum orbiculare and Paspalum notatum are Polygonum type and reproduce sexually via double fertilization. On the other hand, the embryo sacs of Panicum maximum, Pennisetum polystachion and Rhynchelytrum repens reveal Panicum type. These three latter species show apospory followed by parthenogenesis and pseudogamy. In addition, Cenchrus echinatus is autonomous aposporous apomicts, forming both embryo and endosperm spontaneously inside an unreduced embryo sac of Hieracium type.
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