THE BREEDING SYSTEMS OF 6 SPECIES OF ARABIS (BRASSICACEAE)
THE BREEDING SYSTEMS OF 6 SPECIES OF ARABIS (BRASSICACEAE)
复制标题
DOI：
10.2307/2445973
复制
发表时间：
1995-07-01
影响因子：
3
通讯作者：
ROY, BA
中科院分区：
文献类型：
--
作者：
ROY, BA
生物体产生任何性状的遗传变异的能力，包括对病原体的抵抗力，部分取决于繁殖系统。我使用了酶电泳法、杂交实验和细胞学方法来评估经常被锈菌感染的共生阿拉伯物种的繁殖系统。所调查的Arabis holboellii为假无融合生殖，具有较高的群体水平等位酶变异，染色体数目可变(2n，3n，4n)。古尼松阿拉比斯(3n)和木本阿拉比斯(2n)也是假配对，但在种群水平和后代阵列内都没有等位酶变异。粗毛阿拉伯可能是自交的多倍体，也可能是假配子无融合生殖；需要更多的工作来澄清本种的繁育系统。杜氏阿拉比斯和甘地阿拉比斯是有性的，但由于自花受精的优势，表现出很小的遗传变异。使用几种技术来评估这些育种系统是必要的。昆虫排斥表明花粉是结实所必需的，但不能区分有性繁殖和假受精。在没有等位酶变异的多倍体中，电泳法可以得到关于自交程度(纯合性)和无融合生殖(固定杂合性)的信息，但不能区分自交和无融合生殖。当不同基因型之间的杂交只产生母本基因型时，假受精被证实，而细胞学上则通过不规则减数分裂来证实。
The ability of organisms to produce genetic variation for any trait, including resistance to pathogens, is partially determined by breeding system. I used enzyme electrophoresis, crossing experiments, and cytology to assess the breeding systems of co-occurring Arabis species that are often infected by rust fungi. The Arabis holboellii surveyed were pseudogamous apomicts with relatively high population-level allozyme variation, and variable chromosome numbers(2n, 3n, 4n). Arabis gunnisoniana (3n) and Arabis lignifera (2n) were also pseudogamous but showed no allozyme variation either at the population level, or within progeny arrays. Arabis hirsuta may be an autogamous polyploid or it may be a pseudogamous apomict; more work is needed to clarify the breeding system of this species. Arabis drummondii and Arabis crandallii were sexual, but exhibited little genetic variability due to a predominance of self-fertilization. The use of several techniques was necessary to evaluate these breeding systems. Insect exclusion indicated when pollen was necessary for seed set, but could not differentiate between sexual reproduction and pseudogamy. Electrophoresis yielded information on the degree of selfing (as evidenced by homozygosity) and apomixis (fixed heterozygosity), but could not differentiate between autogamy and apomixis in polyploids without allozyme variation. Pseudogamy was confirmed when crosses between dissimilar genotypes yielded only the maternal genotype, and cytologically by irregular meiosis.