摘要
【目的】研究湖北黄精花部形态结构特征和大小孢子发生及雌雄配子体发育过程,以丰富黄精属植物的生殖生物学理论,为进一步开展湖北黄精的品种选育提供依据。【方法】以不同发育时期的湖北黄精花芽为试验材料,用显微观察法观察花部形态结构特征,石蜡切片技术对单花雌雄蕊进行切片观察。【结果】湖北黄精的花被为白色或淡黄绿色,花被筒近喉部稍缢缩;具6枚雄蕊,花丝下端与花被合生,花药开裂方式为纵裂;雌蕊子房上位,3心皮,花柱与子房等长。湖北黄精花药壁由4层细胞组成,成熟的绒毡层具多核,绒毡层发育类型为分泌型;小孢子母细胞减数分裂为连续型,四分体呈左右对称型排列,成熟花粉粒为2-细胞型;存在小孢子发育不同步的现象。雌蕊胚珠具双珠被、厚珠心;四分体呈直线型排列,胚囊发育类型为蓼型;存在双胚囊胚珠现象。在雄蕊的花药壁和雌蕊的子房壁都观察到有束状草酸钙针晶。【结论】湖北黄精雌雄蕊具有较原始的发育特征,虽然在发育过程中都存在异常现象,但雄蕊最终能形成正常的雄配子体,雌蕊低频率的双胚囊现象对总体受精结果影响很小。湖北黄精杂交育种可以选择花药开裂前一时期的花粉,花药壁和子房壁观察到的束状草酸钙针晶无法作为湖北黄精物种鉴定的依据。
[Objective]In order to enrich the reproductive biology theory of Polygonatum Mill.and provide the basis for breeding of Polygonatum zanlanscianense Pamp.,the morphological structure characteristics,megasporogenesis and microsporogenesis,and the development process of male and female gametophytes of P.zanlanscianense were studied.[Methods]The flower buds of P.zanlanscianense at different developmental stages were used as experimental materials.The morphological and structural characteristics of the flowers were observed by microscopic observation,and the single flower pistil and stamen were observed by paraffin sectioning technique.[Results]The perianth of P.zanlanscianense was white or yellowish green,and the perianth tube was slightly constricted near the throat.It had 6 stamens,the lower end of filaments and anthers were united,and the anther was longitudinally split.The pistil ovary was superior,each ovary consisted of 3 carpels,and the style was equal to the ovary.The anther wall of P.zanlanscianense was composed of 4 layers of cells.The mature tapetum had multiple nuclei,and the development type of tapetum was secretory.The meiotic division of microspore mother cells was continuous,tetrads were arranged symmetrically,and mature pollen grains were 2-cell type.The microspore development was not synchronized.Pistil ovule had double integument and thick nucellum.The tetrad was linear and the embryo sac was of polygonum type.The phenomenon of double embryo sac ovule was observed.The calcium oxalate crystals were observed in the anther wall of the stamen and the ovary wall of the pistil.[Conclusion]The stamens and pistils of P.zanlanscianense have more primitive development characteristics.Although there are abnormal phenomena in the development process,the stamens can eventually form normal male gametophytes.The phenomenon of double embryo sacs with low frequency of pistils has little effect on the overall fertilization.The pollen before anther dehysis can be selected for cross breeding of P.zanlanscianense.The bundle-shaped calcium oxalate needles observed in anther wall and ovary wall cannot be used as the basis for species identification of P.zanlanscianense.
作者
李华荣
周财
魏薇
何夫
王业红
陈发菊
LI Huarong;ZHOU Cai;WEI Wei;HE Fu;WANG Yehong;CHEN Faju(Key Laboratory of Plant Genetics and Germplasm Innovation in the Three Gorges Region,Biotechnology Research Center,China Three Gorges University,Yichang,Hubei 443002,China;Wufeng Tujia Autonomous County Modern Agricultural Technology Demonstration Center,Wufeng,Hubei 443400,China)
出处
《西北植物学报》
CAS
CSCD
北大核心
2024年第5期813-823,共11页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金青年项目(32300323)
湖北省中央引导地方科技发展专项(2022BGE265)
湖北省科技建设专项(Z2022387)
五峰土家族自治县政府性资金项目(SDHZ2022262)。
关键词
湖北黄精
大小孢子发生
雌雄配子体
Polygonatum zanlanscianense Pamp.
megasporogenesis and microsporogenesis
male and female gametophyte
