Components of a Cytoplasmic Male Sterility System in Resynthesized and Cultivated Forms of Oilseed Rape (Brassies napus L.)

Male sterile Brassica napus L. plants were found in breeding material which was used for the development of yellow-seeded oilseed rape. The genetic studies indicated that the male sterility was conditioned by the presence of maintamer genes in the nuclear backgrounds of two newly resynthesized B. napus lines, No7076 and No7406, in combination with a male sterility-inducing cytoplasm (S) which is frequently found in cultivated forms of B. napus. Test crosses with nap maintainer and restorer lines support the conclusion that the observed male sterility is of nap type. Furthermore, the Eco RI restriction pattern of mitochondrial DNA of the (S) cytoplasm was identical to that of the nap cytoplasm. Hence, we conclude that we have uncovered a new source of maintainer lines for the nap system which could potentially lead to the production of a better maintainer/restorer system for use in hybrid oilseed rape breeding programmes. However, more work is needed to reduce the glucosinolate content of the maintainer lines and to determine the factors controlling the phenotypic expression of the system.     

Identification of a Stable Maintainer Line for 'Polima' Cytoplasmic Male Sterility in Rapeseed (B. napus L.)

‘Polima’ cytoplasmic male sterility (CMS) was transferred to three different genotypes of B. napus i.e. GSL-1, ISN706 and HNS-8 by repeated backcrossing and was found to be completely stable in the nuclear background of synthetic B. napus genotype, ISN706, derived from a cross B. campestris ssp. oleifera var. brown sarson ×B. oleracea var. botrytis cv. Tusa Katki'. The BC₅ and BC₆ generation lines of ISN706, GSL-1 and HNS-8 with ‘Polima’ CMS were grown under a range of temperature and photo-period conditions to test their stability. No breakdown in sterility was observed in ‘Polima’ ISN706 and, therefore, this genotype can be used as a maintainer for hybrid seed production.     

The Inheritance of Polima Cytoplasmic Male Sterility in Brassica napus L.

The restores tested in this study have only one pair of fertility-restoring genes (Rf) but many temperature-sensitive genes (Ts). The Rf genes are alleles at the same locus. The cytoplasm of the restorers RC₁, RC₂, RC₃ and ‘Huaie’ is male sterile, but that of RC₄, is normal.     

甘蓝型油菜细胞质雄性不育系105A花药败育的细胞学观察

旨在了解并揭示不育系105A的花粉败育时期和细胞学特征,为进一步正确认识细胞质雄性不育系分子机制提供必要参考依据。采用石蜡制片法,对甘蓝型油菜杂交种‘青杂5号’的雄性不育系105A及其恢复系1831R的小孢子发生和花药发育过程进行观察,以确定其花粉败育的时期和细胞学特点。研究结果表明,在不育系105A花药败育过程中,一部分发生于造孢细胞时期,属于无花粉囊败育型;另一部分发生于单核晚期,属于单核败育型,其特点为单核晚期绒毡层细胞膨大向小孢子靠近,并逐步降解,其破裂胞质退化残余物侵入药室,与小孢子混合粘连在一起,甚至有些绒毡层细胞整块脱落,成为染色很深的团块状物质,占据药室一部分空间,最终小孢子降解,花药败育。     

油菜胞质不育类型相关基因研究进展

细胞质雄性不育在油菜杂种优势利用中具有重要作用,研究细胞质雄性不育的不育机理对有效利用杂种优势,实现三系配套及创造强优势组合具有重要意义。介绍Ogu CMS,Pol CMS,Nap CMS等目前国际上主要的甘蓝型油菜细胞质雄性不育类型,综述了线粒体基因组上与CMS性状相关基因的位点或片段的最新研究进展,并讨论当今学术界有关CMS产生机理的主要论点。     

甘蓝型油菜双低萝卜质不育恢复系快速改良技术研究

通过采取不同的常规育种策略和小孢子培养、分子标记辅助选择等现代生物技术,研究了提高甘蓝型油菜萝卜质不育恢复系改良效率的方法。结果表明,在甘蓝型油菜萝卜质不育恢复系杂交转育过程中,采用杂交后代与萝卜质不育系杂交,可使杂交后代分离群体中不具备恢复基因的单株在花期表现出来,无须测交即可进行选择;杂交后代通过小孢子培养,可将稳定纯合时间由传统自交8个世代缩短到3个世代;通过萝卜特异分子标记辅助选择可大大提高选择的精度,减少筛选所需的人力、土地和时间,选择效率提高90%。试验筛选出19个在萝卜质不育恢复系中能够扩增出单一、易于辨别的谱带的SCAR标记引物,其中10个引物在现有的甘蓝型油菜萝卜质不育恢复系中均能检测出特异标记。筛选出的甘蓝型油菜萝卜质不育恢复系的特异分子标记与前人研究存在差异,标记相似系数为48.28%~93.10%。通过分子标记无法区分高硫甙和低硫甙恢复系,选育低硫甙萝卜质不育恢复系还需要借助品质分析仪。成功筛选得到6个甘蓝型油菜低芥酸、低硫甙、抗寒、结角正常、农艺性状优良的萝卜质不育恢复系,为将甘蓝型油菜萝卜质不育杂种优势应用于我国油菜生产奠定了基础。     

一对复等位基因控制的油菜(Brassica napus L.)显性核不育系609AB的遗传验证

在确认609AB不育系类型的基础上,采用临保系测验法和测交后代可育株自交与回交等方法,有效区分了甘蓝型油菜显性核不育的一对复等位和两对显性基因互作控制的两种遗传模式。不育系类型鉴定结果表明609AB是纯合型显性核不育系;遗传分析证明所测恢复系的抑制基因均与Ms等位,不育系可育株的抑制基因也与不育基因等位,确认其     

Identification and Genetic Studies of the Inhibition of Dominant Male Sterility in Brassica napus

By transferring dominant male sterility (DMS), caused by the gene Ms, to genotypes with various types of cytoplasm 12 DMS lines were developed and a number of crosses made between the DMS lines and other genotypes of Brassica napus. During the course of this population improvement programme, 16 genotypes were identified as having the capacity to restore the fertility of F₁ plants with the Ms gene. According to pedigree analysis, the inhibitory gene in those lines probably originated from a few genotypes from Australia and Germany. In further studies the inheritance of the sterility inhibition was determined, providing definite evidence that dominant male sterility and its inhibition in B. napus are controlled by two dominant interacting genes rather than by multiple alleles.     

中国甘蓝型油菜细胞质雄性不育的主要类型及在育种实践中的应用

我国甘蓝型油菜细胞质雄性不育的类型主要有：ogura CMS、nap CMS、pol CMS、Shan 2A CMS、Hau CMS、NCa CMS、Nsa CMS和NEA CMS。pol CMS和Shan 2A CMS在我国油菜杂种优势利用中发挥着重要的作用。新型不育胞质的育成以及在育种上的应用,不仅丰富了细胞质雄性不育种质资源,而且为我国油菜产业可持续发展提供了保证。     

甘蓝型油菜萝卜质雄性不育恢复系的选育

为了获得甘蓝型油菜萝卜细胞质雄性不育(Cytoplasmic male sterility,CMS)高含油量双低品质恢复系,以Ougra-CMS不育胞质杂交种Oug-F1(S(Rfrf))为不育基因和恢复基因供体,高含油量双低亲本D89-44(N(rfrf)为受体,通过杂交、多代同交以及最后自交对恢复基因进行了定向转育...     

Studies on "Three Line" Polima Cytoplasmic Male Sterility Developed in Brassica napus L.

Polima CMS lines can be divided into three groups according to the sensitivity of male sterility to temperature: 1) high temperature CMS lines (62.9%), 2) low temperature CMS lines (28.6 %) and 3) stable CMS lines (8.5 %). The heterosis of Pol CMS hybrids is evident and common in some of the characters tested, especially in plant seed yield and siliqua number. The cytoplasm has no deleterious effects on the FI characters tested.     

Genetic Control of Temperature-Sensitivity of Cytoplasmic Male Sterility (cms) in Chives (Allium schoenoprasum L.)

In earlier experiments with chives (Allium schoenoprasum L.) temperature-sensitive and temperature-insensitive cms plants could be selected. To obtain information about the site and nature of the genetic factor(s) responsible for the temperature sensitivity of the cms, temperature-insensitive and temperauire-sensitive cms plants were crossed with maintainers as well as with one another. In the progenies each genotype was cloned into two clone members, and these were examined concerning their male sterility under normal (20 °C/14 °C, day/night) as well as under constantly high temperatures (24 °C/ 24 °C). The results indicate that the temperature-sensitivity of the cms is controlled by a dominant nuclear gene “T”. This acts like a restorer gene at high temperatures and is ineffective at normal temperatures. Accordingly, important conclusions can be drawn with regard to the selection of temperature-insensitive cms-lines as well as to the propagation of the cmi-lines. The results are discussed in connection with the mitochondrial polypeptides probably responsible for the formation of the cms.     

甘蓝型油菜显性细胞核雄性不育基因的AFLP标记

用甘蓝型油菜双基因显性细胞核雄性不育系Rs1046A和欧洲油菜品种Samourai构建了一个回交分离群体。在群分法（BSA）构建的不育池和可育池中共筛选了256对AFLP引物组合,找到了与不育基因紧密连锁的两个AFLP标记(EA03MC1599和EA07MC01235), 它们与不育基因的遗传图距分别是3.5 cM和5.5 cM,而且位于不育基因的同一侧,标记间相     

甘蓝型油菜细胞质雄性不育恢复基因的遗传研究

通过多年大量的筛选 ,在不同来源甘蓝型油菜中发现了一批恢复系 ,并利用筛选的恢复系中的恢复基因 ,转育出一批恢复性能良好、品质优良、配合力高的恢复系。对这些恢复系的遗传研究结果表明 ,这些不同来源的恢复基因为一对主效基因 ,但这些不同来源的恢复基因的等位性不同     

萝卜雄性不育小孢子发生的形态学研究

对萝卜雄性不育花进行形态学观察，发现两种类型的不育花，即花粉败育型和雄蕊萎缩型。比较研究了可育花及花种类型的不育花小孢子发育的细胞形态学特征，发现萝卜小孢子败育是个连续过程，在造孢细胞时期就已出现败育迹象，在小孢子发育过程中，绒毡层细胞出现液泡化、肥大、增生等异常现象。小孢子的败育与绒毡层细胞异常同步发生，小孢子一直信滞在单核期不再进一步发育，最终消失。另外，在正常可育小孢子发育过程中还偶尔观察到了不育花粉粒的存在。     

利用小孢子培养选育榨菜胞质甘蓝型油菜CMS恢复系研究

以榨菜胞质甘蓝型油菜恢复系材料“06 B033”为母本,优质油菜新品种(系)为父本配制7个杂交组合,并对其F1代进行小孢子培养.结果发现,不同父本的杂交组合在小孢子培养成胚率上表现极显著差异;对获得的DH群体进行对榨菜胞质甘蓝型油菜CMS的恢保性鉴定.结果表明,有5个DH株系对榨菜胞质甘蓝型油菜CMS表现良好的恢复性.     

Establishing Cytoplasmic Male Sterility in Brassica napus by Mitochondrial Recombination with B. tournefortii

Fusion experiments between B. napus and X-ray-treated B. tournefortii protoplasts were carried out to develop cytoplasmic male sterility (ems) in B. napus. From the regenerants, six lines containing male sterile plants were selected; five lines segregated for male sterility, but one line (25–143) was completely male-sterile from the beginning. Molecular analyses of mitochondrial (mt) and chloroplast (cp) DNA of B. napus, B. tournefortii, B. juncea and cms juncea indicated that the original cytoplasmic donor of the cms juncea-system in B. napus was a B. tournefortii form, while the B. napus genotype used for the fusion experiments had a B. campestris cytoplasm. By analysis (it regenerated plants, line 25–143 was identified as possessing mt-DNA recombined between B. campestris and B. tournefortii. with the major part derived from B. campestris. No differences were detected between epDNAs from H. campestris and from line 25—143. The other five lines were similar to B. campestris with all the probes used. The low frequency of sterile lines from the fusion experiments and the inheritance of the cms in segregating progenies are both discussed.     

Genetic Control of Tetracycline Sensitivity of Cytoplasmic Male Sterility (cms) in Chives (Allium schoenoprasum L.)

The expression of cms in chives is controlled by a cytoplasmic factor (5), a restorer gene X/x (Tatlioglu 1982) and a temperature gene T/t (Tatlioglu 1987). In recent investigations (Tatlioglu 1986) it could be shown that tetracycline also influences the expression of 0731. To obtain information about the genetic control of tetracycline sensitivity of cms, tetracycline-sensitive and tetracycline-insensitive cms plants were crossed with each other as well as with maintainers and the reaction of their progeny to tetracycline base was investigated. The results indicated that the promotion of fertility due to high-temperature conditions (24°C/24 °C, day/night) and tetracycline · base are independent of each other. The results of crosses can be explained by a nuclear gene, A/a, causing the tetracycline sensitivity when recessive. By using different genotypes of the three loci for restoration, temperature and tetracycline sensitivity highly advantageous material can be constructed for the investigation of the interaction between the nuclear and the mitochondrial genome in higher plants, for the molecular and functional basis of cms and for its use in plant breeding.     

Synthesis of Alloplasmic Brassica campestris as a New Source of Cytoplasmic Male Sterility

Cytoplasmic male, steriles of Brassica campestris ssp. oleifera var. brown sarson were obtained m BO generation progenies Following the repeated back-crossing of the synthetic alloploid B. oxyrrhina (2n = 18, OO) ×B. campestris. (2n = 20, AA). Alloplasmic B. campestris plants resemble B. campestris in morphology and growth pattern and do not exhibit any trait of B. oxyrrhina, However, the leave; arc mildly chlorophyll deficient in the earlier stages and turn green at late stages In the development. The reproductive parts do not show and abnormalities except that the anthers are smaller and slenderer that the normal ones and are non dehiscent, containing only sterile pollen.     

显性核不育油菜圆叶纯合两型系Gd1AB的选育

采用杂交、兄妹交和自交等育种手段，育成园叶显性纯合两型系Gd1AB。利用该两型系与花叶临保系进行全不育系制种，圆叶可作为苗期育性的指示性状，能有效地区别纯合两型系内可育株迟拔或漏拔而产生的杂株，从而提高全不育系的纯度。