植物学报
植物學報
식물학보
BULLETIN OF BOTANY
2009年
6期
682-693
,共12页
尚娅佳%申家恒%郭德栋%丁常宏%李伟%陆俊萍
尚婭佳%申傢恆%郭德棟%丁常宏%李偉%陸俊萍
상아가%신가항%곽덕동%정상굉%리위%륙준평
自发分裂%甜菜%成熟胚囊%单体附加系%超微结构
自髮分裂%甜菜%成熟胚囊%單體附加繫%超微結構
자발분렬%첨채%성숙배낭%단체부가계%초미결구
autonomous division%Beta vulgaris%mature embryo sac%monosomic addition line%ultrastructura
以甜菜无融合生殖单体附加系M14(Beta vulgaris,2n=18+1)为实验材料,利用电子显微镜技术对成熟胚囊及其超微结构进行研究.结果表明:M14成熟胚囊包括1个卵细胞、2个退化的助细胞、1个具有次生核的中央细胞和3-6个反足细胞.其卵细胞具有3种不同的形态:(1)极性正常的卵细胞,细胞核位于合点端,细胞质含有大量核糖体、线粒体、内质网等细胞器:(2)细胞核位于细胞中央:(3)细胞核位于珠孔端,且后2种形态细胞器的种类与数量少.大多数胚囊中的2个助细胞在开花前已退化.中央细胞的次生核位于反足细胞附近:未经受精自发分裂前的卵细胞与中央细胞的细胞核大、核仁明显,细胞器的种类与数量多,呈现旺盛代谢活动特征,成为二倍体孢子无融合生殖过程中,卵细胞与次生核自发分裂的细胞学标志.
以甜菜無融閤生殖單體附加繫M14(Beta vulgaris,2n=18+1)為實驗材料,利用電子顯微鏡技術對成熟胚囊及其超微結構進行研究.結果錶明:M14成熟胚囊包括1箇卵細胞、2箇退化的助細胞、1箇具有次生覈的中央細胞和3-6箇反足細胞.其卵細胞具有3種不同的形態:(1)極性正常的卵細胞,細胞覈位于閤點耑,細胞質含有大量覈糖體、線粒體、內質網等細胞器:(2)細胞覈位于細胞中央:(3)細胞覈位于珠孔耑,且後2種形態細胞器的種類與數量少.大多數胚囊中的2箇助細胞在開花前已退化.中央細胞的次生覈位于反足細胞附近:未經受精自髮分裂前的卵細胞與中央細胞的細胞覈大、覈仁明顯,細胞器的種類與數量多,呈現旺盛代謝活動特徵,成為二倍體孢子無融閤生殖過程中,卵細胞與次生覈自髮分裂的細胞學標誌.
이첨채무융합생식단체부가계M14(Beta vulgaris,2n=18+1)위실험재료,이용전자현미경기술대성숙배낭급기초미결구진행연구.결과표명:M14성숙배낭포괄1개란세포、2개퇴화적조세포、1개구유차생핵적중앙세포화3-6개반족세포.기란세포구유3충불동적형태:(1)겁성정상적란세포,세포핵위우합점단,세포질함유대량핵당체、선립체、내질망등세포기:(2)세포핵위우세포중앙:(3)세포핵위우주공단,차후2충형태세포기적충류여수량소.대다수배낭중적2개조세포재개화전이퇴화.중앙세포적차생핵위우반족세포부근:미경수정자발분렬전적란세포여중앙세포적세포핵대、핵인명현,세포기적충류여수량다,정현왕성대사활동특정,성위이배체포자무융합생식과정중,란세포여차생핵자발분렬적세포학표지.
We investigated by electron microscopy the ultrastructural character of the mature embryo sac in the chromosome-9monosomic addition line of Beta corolliflora Zoss. in sugar beet, designated M14. The mature embryo sac of M14 consisted of an egg cell, two synergids, a central cell with a secondary nucleus, and 3-6 antipodal cells. The egg cells in different embryo sacs showed different polarity and metabolic activity. They were classified into three types according to the polarity of egg cells: (1) egg cell with regular polarity-the nucleus was located at the chalazal end, and its cytoplasm was rich in organelles such as ribosomes,mitochondria and endoplasmic reticulum; (2) egg cell with a nucleus at the micropylar end, and (3) egg cell with a centrally located nucleus. The eggs of the third type contained fewer organelles in cytoplasm. The two synergids degenerated before anthesis in most mature embryo sacs. The secondary nucleus, which was close to the antipodals, showed strong metabolic activity. Both the egg cell and the central cell contained large nuclei with distinct nucleoli and numerous organelles. The egg and the central cell were suggested to be active in metabolism, which could be a label of the autonomous division of unfertilized egg call and central cell in diplospory.