Li Zaiyun, Ceccarelli M, Minelli S, Contento A, Liu Yan, Cionini P G
National Key Lab of Crop Genetic Improvement, Department of Agronomy, Huazhong Agricultural University, Wuhan 430070, China.
Sci China C Life Sci. 2003 Feb;46(1):104-12. doi: 10.1007/BF03182690.
Interspecific and intergeneric hybridizations have been widely used in plant genetics and breeding to construct stocks for genetic analysis and to introduce into crops the desirable traits and genes from their relatives. The intergeneric crosses between Brassica juncea (L.) Czern. & Coss., B. carinata A. Braun and Orychophragmus violaceus (L.) O. E. Schulz were made and the plants produced were subjected to genomic in situ hybridization analysis. The mixoploids from the cross with B. juncea were divided into three groups. The partially fertile mixoploids in the first group (2n = 36-42) mainly contained the somatic cells and pollen mother cells (PMCs) with the 36 chromosomes of B. juncea and additional chromosomes of O. violaceus. The mixoploids (2n = 30-36) in the second and third groups were morphologically quite similar to the mother plants B. juncea and showed nearly normal fertility. The plants in the second group produced the majority of PMCs (2n = 36) with their chromosomes paired and segregated normally, but 1-4 pairs of the O.violaceus chromosomes were included in some PMCs. The plants in the third group produced only PMCs with the 36 B. juncea chromosomes, which were paired and segregated normally. The mixoploids (2n = 29-34) from the cross with B. carinata produced the majority of PMCs (2n = 34) with normal chromosome pairing and segregation, but some plants had some PMCs with 1-3 pairs of chromosomes from O. violaceus and other plants had only PMCs with the B. carinata chromosomes. The Brassica homozygous plants and aneuploids with complete or partial chromosome complements of Brassica parents and various numbers of O. violaceus chromosomes were derived from these progeny plants. The results in this study provided the molecular cytogenetic evidence for the separation of parental genomes which was previously proposed to occur in the hybridizations of these two genera.
种间和属间杂交已广泛应用于植物遗传学和育种中，用于构建遗传分析的材料，并将其亲缘种的优良性状和基因导入作物。进行了芥菜（Brassica juncea (L.) Czern. & Coss.）、埃塞俄比亚芥（B. carinata A. Braun）与诸葛菜（Orychophragmus violaceus (L.) O. E. Schulz）之间的属间杂交，并对产生的植株进行了基因组原位杂交分析。与芥菜杂交产生的混倍体分为三组。第一组部分可育的混倍体（2n = 36 - 42）主要包含具有36条芥菜染色体和诸葛菜额外染色体的体细胞和花粉母细胞（PMCs）。第二组和第三组的混倍体（2n = 30 - 36）在形态上与母本芥菜非常相似，且育性接近正常。第二组植株产生的大多数花粉母细胞（2n = 36）染色体配对和分离正常，但部分花粉母细胞中包含1 - 4对诸葛菜染色体。第三组植株只产生具有36条芥菜染色体的花粉母细胞，其染色体配对和分离正常。与埃塞俄比亚芥杂交产生的混倍体（2n = 29 - 34）产生的大多数花粉母细胞（2n = 34）染色体配对和分离正常，但一些植株有部分花粉母细胞含有1 - 3对诸葛菜染色体，而其他植株只有含埃塞俄比亚芥染色体的花粉母细胞。从这些后代植株中获得了具有芥菜亲本完整或部分染色体组以及不同数量诸葛菜染色体的芥菜纯合植株和非整倍体。本研究结果为之前提出的这两个属杂交中亲本基因组分离提供了分子细胞遗传学证据。
