PDF(Pubmed)
Abstract：
BACKGROUND: Unreduced gamete formation during meiosis plays a critical role in natural polyploidization. However, the unreduced gamete formation mechanisms in Triticum turgidum-Aegilops umbellulata triploid F1 hybrid crosses and the chromsome numbers and compostions in T. turgidum-Ae. umbellulata F2 still not known.
RESULTS: In this study, 11 T.turgidum-Ae. umbellulata triploid F1 hybrid crosses were produced by distant hybridization. All of the triploid F1 hybrids had 21 chromosomes and two basic pathways of meiotic restitution, namely first-division restitution (FDR) and single-division meiosis (SDM). Only FDR was found in six of the 11 crosses, while both FDR and SDM occurred in the remaining five crosses. The chromosome numbers in the 127 selfed F2 seeds from the triploid F1 hybrid plants of 10 crosses (no F2 seeds for STU 16) varied from 35 to 43, and the proportions of euploid and aneuploid F2 plants were 49.61% and 50.39%, respectively. In the aneuploid F2 plants, the frequency of chromosome loss/gain varied among genomes. The chromosome loss of the U genome was the highest (26.77%) among the three genomes, followed by that of the B (22.83%) and A (11.81%) genomes, and the chromosome gain for the A, B, and U genomes was 3.94%, 3.94%, and 1.57%, respectively. Of the 21 chromosomes, 7U (16.54%), 5 A (3.94%), and 1B (9.45%) had the highest loss frequency among the U, A, and B genomes. In addition to chromosome loss, seven chromosomes, namely 1 A, 3 A, 5 A, 6 A, 1B, 1U, and 6U, were gained in the aneuploids.
CONCLUSIONS: In the aneuploid F2 plants, the frequency of chromosome loss/gain varied among genomes, chromsomes, and crosses. In addition to variations in chromosome numbers, three types of chromosome translocations including 3UL·2AS, 6UL·1AL, and 4US·6AL were identified in the F2 plants. Furthermore, polymorphic fluorescence in situ hybridization karyotypes for all the U chromosomes were also identified in the F2 plants when compared with the Ae. umbellulata parents. These results provide useful information for our understanding the naturally occurred T. turgidum-Ae. umbellulata amphidiploids.
RESULTS: In this study, 11 T.turgidum-Ae. umbellulata triploid F1 hybrid crosses were produced by distant hybridization. All of the triploid F1 hybrids had 21 chromosomes and two basic pathways of meiotic restitution, namely first-division restitution (FDR) and single-division meiosis (SDM). Only FDR was found in six of the 11 crosses, while both FDR and SDM occurred in the remaining five crosses. The chromosome numbers in the 127 selfed F2 seeds from the triploid F1 hybrid plants of 10 crosses (no F2 seeds for STU 16) varied from 35 to 43, and the proportions of euploid and aneuploid F2 plants were 49.61% and 50.39%, respectively. In the aneuploid F2 plants, the frequency of chromosome loss/gain varied among genomes. The chromosome loss of the U genome was the highest (26.77%) among the three genomes, followed by that of the B (22.83%) and A (11.81%) genomes, and the chromosome gain for the A, B, and U genomes was 3.94%, 3.94%, and 1.57%, respectively. Of the 21 chromosomes, 7U (16.54%), 5 A (3.94%), and 1B (9.45%) had the highest loss frequency among the U, A, and B genomes. In addition to chromosome loss, seven chromosomes, namely 1 A, 3 A, 5 A, 6 A, 1B, 1U, and 6U, were gained in the aneuploids.
CONCLUSIONS: In the aneuploid F2 plants, the frequency of chromosome loss/gain varied among genomes, chromsomes, and crosses. In addition to variations in chromosome numbers, three types of chromosome translocations including 3UL·2AS, 6UL·1AL, and 4US·6AL were identified in the F2 plants. Furthermore, polymorphic fluorescence in situ hybridization karyotypes for all the U chromosomes were also identified in the F2 plants when compared with the Ae. umbellulata parents. These results provide useful information for our understanding the naturally occurred T. turgidum-Ae. umbellulata amphidiploids.
摘要：
背景：减数分裂过程中未减少的配子形成在自然多倍化中起着关键作用。然而,Triticum-Aegilopsumbellulata三倍体F1杂种杂交中未减少的配子形成机制以及T.turgidum-Ae的染色体数目和组成。伞形F2仍然未知。
结果：在这项研究中，11T.turgidum-Ae.伞形三倍体F1杂种杂交是通过远距离杂交产生的。所有三倍体F1杂种都有21条染色体和两个减数分裂恢复的基本途径，即一级恢复(FDR)和单级减数分裂(SDM)。在11个十字架中只有6个被发现FDR,而FDR和SDM均发生在其余五个杂交中。来自10个杂交的三倍体F1杂种植物(STU16没有F2种子)的127个自交F2种子中的染色体数目在35到43之间变化,整倍体和非整倍体F2植物的比例分别为49.61%和50.39%,分别。在非整倍体F2植物中，染色体丢失/获得的频率因基因组而异。在三个基因组中，U基因组的染色体丢失最高(26.77%)，其次是B（22.83％）和A（11.81％）基因组，和A的染色体增益，B,U基因组占3.94%，3.94%,和1.57%，分别。在21条染色体中，7U（16.54%），5A（3.94%），1B(9.45%)在美国中损失频率最高，A,B基因组。除了染色体丢失,七个染色体,即1A，3A,5A,6A,1B,1U,6U，在非整倍体中获得。
结论：在非整倍体F2植物中，染色体丢失/获得的频率因基因组而异，染色体,和十字架。除了染色体数目的变化,三种类型的染色体易位，包括3UL·2AS，6UL·1AL，在F2植物中鉴定出4US·6AL。此外，与Ae相比，在F2植物中还鉴定了所有U染色体的多态性荧光原位杂交核型。伞形的父母。这些结果为我们理解自然发生的T.turgidum-Ae提供了有用的信息。伞形二倍体。
结果：在这项研究中，11T.turgidum-Ae.伞形三倍体F1杂种杂交是通过远距离杂交产生的。所有三倍体F1杂种都有21条染色体和两个减数分裂恢复的基本途径，即一级恢复(FDR)和单级减数分裂(SDM)。在11个十字架中只有6个被发现FDR,而FDR和SDM均发生在其余五个杂交中。来自10个杂交的三倍体F1杂种植物(STU16没有F2种子)的127个自交F2种子中的染色体数目在35到43之间变化,整倍体和非整倍体F2植物的比例分别为49.61%和50.39%,分别。在非整倍体F2植物中，染色体丢失/获得的频率因基因组而异。在三个基因组中，U基因组的染色体丢失最高(26.77%)，其次是B（22.83％）和A（11.81％）基因组，和A的染色体增益，B,U基因组占3.94%，3.94%,和1.57%，分别。在21条染色体中，7U（16.54%），5A（3.94%），1B(9.45%)在美国中损失频率最高，A,B基因组。除了染色体丢失,七个染色体,即1A，3A,5A,6A,1B,1U,6U，在非整倍体中获得。
结论：在非整倍体F2植物中，染色体丢失/获得的频率因基因组而异，染色体,和十字架。除了染色体数目的变化,三种类型的染色体易位，包括3UL·2AS，6UL·1AL，在F2植物中鉴定出4US·6AL。此外，与Ae相比，在F2植物中还鉴定了所有U染色体的多态性荧光原位杂交核型。伞形的父母。这些结果为我们理解自然发生的T.turgidum-Ae提供了有用的信息。伞形二倍体。
