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在长春蒲公英(Taraxacum junpeianum Kitam.)株群中发现雄性不育现象,为研究其败育机理及特点,探寻其不育基因,采用形态观察法、石蜡切片技术和染色体压片法,对长春蒲公英野生型及其雄性不育株的花药发育过程和花粉母细胞减数分裂过程进行了观察。结果表明:(1)长春蒲公英雄性不育株花药中部发红、干瘪、无花粉散出。与野生型比较,雄性不育株雄蕊更短,子房更窄,种子形态更加狭长;(2)长春蒲公英雄性不育株败育时期为四分体到单核小孢子前期,败育方式为小孢子自身异常发育,绒毡层异常分解,互相粘连败育;(3)长春蒲公英雄性不育株花粉母细胞减数分裂二分体时期出现落后微核,随后产生极少四分体,并且四分体产生大量染色体桥,小孢子营养物质流失,彻底败育。因此,长春蒲公英雄性不育株败育彻底、稳定,并且有种的特点。小孢子自身异常发育和绒毡层异常分解是导致败育的主要原因。
In order to study its mechanism of abortion and its characteristics, male sterility was found in a strain of Taraxacum junpeianum Kitam. The morphological observation, paraffin section technique and chromosome tabletting method were used to study the male sterility of Changchun dandelion Anther development and pollen mother cell meiosis in wild type and their male sterile lines were observed. The results showed that: (1) The middle part of anther of Changchun dandelion male sterile plants was red, shriveled and pollens were not polluted. Compared with the wild type, male sterile plants had shorter stamens, narrower ovary and narrower seed morphology. (2) The abortive stage of Changchun dandelion male sterile plants was tetrad to early stage of mononuclear microspore, Microspore self-development, abnormal tapetum decomposition, mutual adhesion and abortion; (3) Changchun dandelion male sterile plant pollen mother cell meiosis dysentery occurred late micronuclei, and then produce very few tetrad, and Tetrahedron produces a large number of chromosome bridges, microscopic nutrient loss, completely abortion. Therefore, Changchun dandelion male sterility abortion thorough, stable, and a species of characteristics. Microspore self-abnormal development and abnormal abnormal tapetum is the leading cause of abortion.