射干（Iris domestica）无融合生殖鉴定

发布时间：2018-11-28 18:06

【摘要】：射干(Iris domestica)与野鸢尾(I.dichotoma)同为鸢尾科(Iridaceze)鸢尾属(Iris)植物,本试验通过射干与三种花色的野鸢尾进行杂交鉴定射干的无融合生殖。射干分别与紫花野鸢尾、白花野鸢尾和黄花野鸢尾进行正反交,获得F1群体。从F1群体的每个组合中随机选取20个株系进行植物性性状的调查。从射干做母本的三个组合中每个组合随机选取4个株系进行自交实验,每个组合获得80个株系,从80个株系中随机选取20个株系进行植物学性状调查,分析射干做母本的三个组合的F2群体是否出现性状分离。使用SNP(single nucleotide polymorphism,单核昔酸多态性)分子标记法对射干与三种花色野鸢尾正反交后代的13个株系进行了杂种真实性鉴定。使用花粉管荧光观察和石蜡切片的方法观察射干与野鸢尾杂交及射干自交过程中的花粉管行为和双受精过程。结果表明,分别以三种花色野鸢尾做母本的杂交后代的植物学性状表现为双亲的中间型,杂交后代的花色、花型、果子、种子等植物学性状表现出和亲本的差异性。以射干为母本与三种花色野鸢尾进行杂交获得的后代在植物学性状上表现出偏母遗传,杂交后代的花色、花型、果实以及种子均未表现出与母本的差异。在对射干做母本的杂交后代自交F2的植物学性状调查后发现,三个组合的F2群体并未出现性状分离,三个组合的F2在花色、开花时间、闭花时间、果实形态、种子形态性状表现上均与其亲本或射干差异不显著。但在株高、花冠幅、内外花被宽等一些数量性状上,F2与其亲本或射干差异显著,不同组合的F2群体之间株高、花冠幅、内外花被长、内外花被宽差异均不显著。SNP分子标记方法首次在鸢尾属植物中成功应用。紫花野鸢尾×射干的两个株系、白花野鸢尾×射干的两个株系和黄花野鸢尾×射干的三个株系均为真杂种,其杂交后代中既有来源于母本野鸢尾的SNP位点,也有来源于父本射干的SNP位点。而射干×紫花野鸢尾、射干×白花野鸢尾、射干×黄花野鸢尾三个组合的六个株系均为假杂种,杂交后代只有来源于母本射干的SNP位点,并没有直接来源于父本野鸢尾的SNP位点。通过射干作为母本与三种花色野鸢尾杂交后代性状一致且均有偏母特性、其杂交后代自交F2也未出现性状分离的表现和SNP分子标记法的鉴定结果为假杂种可以证明射干为无融合生殖,这是第一次在鸢尾属植物中发现无融合生殖现象。对射干与野鸢尾杂交后的花粉管行为的观察发现,野鸢尾的花粉能够在射干的柱头上萌发伸长到射干的胚珠内,但是出现了花粉管缠绕、萌发伸长时间比射干自交要慢的现象。使用石蜡切片方法对射干自交和射干与野鸢尾杂交的双受精过程进行了观察,射干自交在授粉后3d左右完成双受精过程,并未观察到射干与野鸢尾杂交完成双受精的过程。
[Abstract]:Ejaculated (Iris domestica) and I.dichotoma are (Iris) plants of (Iridaceze) Iris family. In this experiment, the ejaculated apomixis was identified by hybridization with three species of wild iris. F _ 1 population was obtained by direct and negative crossing with wild iris of purple flower, wild iris of white flower and iris of yellow flower respectively. Twenty lines were randomly selected from each combination of F1 population to investigate the plant characters. Four lines were randomly selected from each of the three combinations to carry out self-crossing experiments. 80 lines were obtained from each combination, and 20 lines were randomly selected from 80 lines to investigate the botanical characters. The trait segregation of F 2 population with three combinations of ejaculation as female parent was analyzed. SNP (single nucleotide polymorphism, mononuclear acid polymorphism (SNP (single nucleotide polymorphism,) molecular marker method was used to identify the authenticity of 13 hybrids of Radix perforatum and three species of iris. The pollen tube behavior and the process of double fertilization were observed by fluorescence observation of pollen tube and paraffin section. The results showed that the botanical characters of hybrid progenies with three kinds of flower color wild iris as female parent were the middle type of parents, and the difference of botanical characters such as flower color, flower type, fruit, seed and so on of hybrid progeny showed difference with their parents. The results showed that the progeny of shoot dry as female parent and three kinds of flower color wild iris showed partial maternal inheritance in botanical characters, and the flower color, flower shape, fruit and seed of hybrid progeny showed no difference with female parent. After investigating the botanical characters of F _ 2 of female progeny, it was found that there was no segregation of characters in F2 population of three combinations, and the F _ 2 of three combinations were in flower color, flowering time, closing flower time and fruit morphology. There was no significant difference between seed morphological characters and their parents or ejaculation. But in some quantitative characters, such as plant height, Corolla width, width of inner and outer perianth, F2 had significant difference with their parents or shoot stem. The plant height, Corolla width, length of inner and outer perianth were different among F2 populations of different combinations. There was no significant difference in the width of perianth between internal and external flowers. SNP molecular marker method was successfully used in Iris for the first time. Two lines of Iris sinensis 脳 shoot stem, two lines of Iris albicans 脳 shoot dry and three strains of Iris huanghuaensis 脳 Radix perforated were true hybrids, and there were SNP loci derived from female iris in their hybrid progenies. There are also SNP loci derived from male ejaculation. The six lines of the three combinations were all pseudohybrids, and only the SNP loci derived from the female parent were found in the hybrid progenies, and the three combinations were all pseudohybrids, and the three combinations were all pseudohybrids, and the six lines of the three combinations were all pseudohybrids, and the hybrid progenies were only derived from the SNP loci of the female parent. There was no direct source of SNP loci from the male wild iris. By means of shoot dry as a female parent and three kinds of flower color wild iris hybrid progeny, the characters of the progenies are consistent and both have the characteristic of partial motherhood. There was no segregation of traits in F _ 2 and the result of SNP molecular marker analysis showed that the pseudo-hybrid could prove that the shoot stem was apomixis. This was the first time that apomixis was found in Iris. The pollen germination and elongation of the pollen of Iris wilfordii were found to be able to germinate and extend to the ovules on the stigma of the shoot, but the pollen tube was entangled, and the time of germination and elongation was slower than that of self-pollination in the pollen tube behavior after the crossing between the shoot and the iris, the pollen of the wild iris could germinate and extend to the ovules on the stigma of the shoot. The process of double fertilization was observed by using paraffin section method. The process of double fertilization was completed about 3 days after pollination, but the process of double fertilization was not observed.
【学位授予单位】：沈阳农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S682.19

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