大豆质核互作雄性不育系NJCMS3A双亲雄性育性基因的SSR标记

利用大豆质核互作雄性不育系NJMCS3A的质、核供体亲本N21566和N21249构建F₂和BC₁F₁育性分离群体进行雄性育性的遗传分析与基因定位。结果表明, F₁正反交可育,F₂和BC₁F₁的可育株与不育株分离比例经χ²测验分别符合3∶1和1∶1,表明NJCMS3A供体亲本雄性育性由一对基因控制,可育等位基因为显性。该基因可能是NJCMS3A的一个恢复基因。选用793对SSR引物对F₂和BC₁F₁群体分别进行育性基因定位,发现该育性基因位于O连锁群上,在Satt331和Satt477标记之间,与Satt331、CSSR133和Satt477标记距离的次序一致,分别为8.1~10.4 cM、11.4~16.4 cM、13.3~19.2 cM。     

带遗传标记的玉米基因雄性不育的发现及遗传和利用研究

1992年在玉米族远缘杂交组合3402F3(丹340×403-2)中首次发现带标记性状的基因雄性不育(GMS)材料。 遗传分析结果表明, 不育性受一对隐性基因控制。 当不育株(A)与可育株(B)进行兄妹交, 育性分离比例接近1∶1; 而可育株(B)自交的后代, 可育株与不育株的分离比例为3∶1。 连锁遗传分析结果证明, 不育基因(ms°)与标记性状     

水稻新质源(CMS-FA)雄性不育恢复基因的遗传研究

发掘水稻新型雄性不育细胞质源CMS-FA,育成系列优质米不育系和系列新质源恢复系,组配成强优势杂交稻组合的基础上研究新质源雄性不育恢复系的恢复基因遗传。采用新质源(CMS-FA)不育系金农1A与恢复系金恢3号杂交获得杂交F₁代种子,种植F₁代,收获自交F₂代种子。用F₁分别与不育系或保持系回交,获得(不育系//不育系/恢复系和不育系/恢复系//保持系)2个测交群体。同时种植P₁、P₂、F₁、F₂、B₁F₁和B₂F₁等群体,考察花粉染色率、套袋结实率和自然结实率,卡平方测验遗传分离适合度。结果表明,不育系与恢复系杂交F₁代正常可育,育性恢复(可育)基因为显性遗传。F₂代分离出可育︰不育适合3︰1,育性恢复(可育)基因为1对显性基因控制。B₁F₁和B₂F₁代2个测交群体的可育︰不育都适合1︰1分离规律,验证了F₂代育性恢复(可育)单基因的遗传模式。暂时确定新质源(CMS-FA)核质互作三系的基因型为不育系S(SS)、保持系F(SS)和恢复系S(FF)。     

水稻三明显性核不育基因的初步鉴定

2001年在福建省尤溪县西城镇凤元村进行两系核不育系育性鉴定时, 在SE21S/Basmati 370组合编号为S221的800多株F₂代分离群体中发现1株与其他不育株的花粉败育形态不同的植株。经测交、回交、姐妹交的后代育性分离调查, 不育株与可育株呈1︰1分离, 以不育株为母本与普通品种配制杂交组合, 其后代育性呈1︰1分离, 可育株后代分离不出不育株, 表明S221不育性受核内1对显性不育基因控制。     

甘蓝型油菜细胞核雄性不育材料118 A的遗传与应用研究

经遗传研究表明：核不育系118A的不育性受两对隐性重叠不育基因和一对隐性上位互作基因控制，不育基因与117AB、S45AB的不育基因为非等位基因，当两对基因隐性纯合，另一对上位互作基因为显性（RfRf或Rfrf）时，植株表现不育（aabbRfRf或aabbRfrf），其相应临保系的基因型为3对隐性纯合体（aabbrfrf）。纯合两型系内不育株与可育株（AabbRfRf或aaBbRfRf）杂交，F1为1：1的育性分离，系内可育株自交为3：1的育性分离。利用纯合两型系AabbRfRf或aaBbRfRf中不育株和可育株成对兄妹交可生产纯合两型系和不育系118A，不育系和临保系杂交生产全不育系118CA（aabbRfrf），全不育系与恢复系（AA-或-BB）杂交生产杂交种。     

抗丝黑穗病、抗败育高粱A2细胞质雄性不育系A2Sx3197的选育

A₁Tx3197曾经是我国广泛应用的高粱细胞质雄性不育系,20世纪70年代末,由于高粱丝黑穗病病菌生理小种分化,该不育系以及用其配制的杂交种逐渐失去了对高粱丝黑穗病菌的抗性。同时该不育系小花败育日渐严重,制种产量极低,甚至造成绝收。为了改良A₁Tx3197的抗病性及抗败育性,本研究利用A₂保持系在A₁位点含有A₁育性恢复基因MS₁MS₁和在A₁细胞质背景下表现恢复的特点,以不育系A₁Tx3197为轮回亲本,以含有抗丝黑穗病、抗败育基因的BV₄为供体,通过杂交和多代回交,得到含有双抗基因的A₂类型细胞质雄性不育的保持系BSx3197(MS₁ms₁ms₂ms₂),在该材料自交的同时,用其对A₂细胞质雄性不育系进行细胞核代换,经过多代回交和自交,最终育成了抗丝黑穗病、抗败育的A₂细胞质雄性不育系A₂Sx3197和保持系BSx3197(MS₁MS₁ms₂ms₂)。结果表明,新选育的不育系A₂Sx3197在A₁和A₅细胞质背景下表现恢复,在A₂、A₃、A₄、A₆和9E细胞质背景下表现不育,丝黑穗平均发病率为0~0.8%,败育率为0~8.4%,抗丝黑穗病性、抗败育性明显优于被改良不育系,接近或达到抗原供体BV₄水平;而在抽穗期、株高、穗长、穗宽、千粒重、穗粒重、粒色、壳色、穗形、穗型等主要性状方面与A₁Tx3197差异不显著。     

高含油量双低油菜隐性核不育系沪228A的选育

沪228A是上海市农业科学院通过回交、测交、兄妹交和小孢子培养自主选育的纯合两型系20228 AB和临保系M-6477杂交培育的甘蓝型高含油量双低油菜隐性核不育全不育系,于2011年通过上海市农作物品种审定委员会审定.选育的隐性核不育两型系20228 AB,芥酸含量为0.87％,硫苷含量15.45μmol/g,含油量为48.25％.临保系M-6477,保持率为100％,芥酸含量为0.06％,硫苷含量20.38μmol/g,含油量为49.44％.全不育系沪228 A,不育度和不育株率为100％.利用该不育系配制的4个强优势杂交组合通过了上海市农作物品种审定委员会审定.     

甘蓝型高油分隐性上位互作核不育系粱全1504A的选育研究

粱全1504A是贵州粱丰农业科技有限公司以引进甘蓝型油菜杂交种核优202杂交种后代可育株连续自交、测交、兄妹交育成纯合两型系(粱纯4A),与引进甘蓝型油菜杂交种核优202杂交种后代不育株和从贵州省油菜所引进隐性上位互作核不育黄籽临保系(S2375C-15)杂交转育的临保系(粱临4C)组配的甘蓝型油菜隐性上位互作核不育系,该不育系综合性状优良,株型紧凑,含油量较高,一般配合力较高,组配的隐性上位互作核不育杂交油菜组合丰产性好,抗性好,品质性状优良,有广泛的应用前景。     

玉米雄性不育突变体x50的基因定位与遗传分析

为了挖掘雄性不育种质资源，鉴定雄性育性基因，为玉米雄性不育化制种提供基础材料。以玉米雄性不育突变体x50为试验材料，研究突变体雄性不育表型，构建x50与自交系Mo17的F₁和F₂群体，确定突变体x50雄性不育性状的遗传模式。以F₂群体为材料，应用图位克隆技术定位雄性育性基因X50,通过基因等位性测验确定候选基因。结果显示，与野生型相比，雄性不育突变体x50花药不能从颖壳露出，花药体积较小且萎蔫，无成熟花粉粒形成。F₁群体植株均表现为雄性可育，F₂群体植株出现雄性育性分离，可育植株与不育植株分离比例符合3∶1,说明突变体x50不育性状受1对隐性核基因控制。通过图位克隆方法将雄性育性基因X50定位于玉米第2染色体分子标记2-4901与2-4963之间，物理区间为237.42～241.39 Mb。定位区间内候选基因分析发现，区间存在玉米雄性不育基因ZmMs33。以ms33纯合突变体ms33-6029和ms33-6052分别与x50杂合型+/x50杂交，杂交后代可育植株与不育植株分离比...     

甘蓝型油菜隐性核不育系ZWAB的选育及其临时保持系和恢复系的筛选

利用甘蓝型油菜隐性核不育杂交组合川油14中发现的不育株作母本、引进英国品种Bristal作父本杂交,F1代与中油821进行复合杂交,于后代中连续选择不育株与可育株兄妹交,获得稳定的两型系ZWAB.通过对其广泛测交,筛选出能完全保持其不育性的临时保持系和完全恢复的恢复系.临保不育系和恢复系配制的杂交种具有较强的杂种优势,有着良好的利用前景.     

白菜型油菜双显性核不育896AB恢复系基因型的鉴定

以白菜型油菜双显性核不育896AB为材料，采用成对兄妹交和相应可育株自交，验证显性不育基因的遗传;用恢复系与全不育系测交，测交一代与临保系复交，验证显性恢复基因的抑制作用，并区分F2代育性分离为3:1和13:3的遗传类型。经4个年度的研究认为，育性是由一对显性不育基因MSMS和一对显性可育基因RfRf互作控制，且显性可育基     

Determination of the frequencies of restorer- and maintainer-alleles involved in CMS1 and CMS2 in German chive varieties

There are two cytoplasmic male sterility (CMS)‐systems in chives (Allium schoenoprasum L.), which can be employed in hybrid breeding. However, the probability for selection of maintainer genotypes from German open pollinated varieties is not known. Therefore, the allelic frequencies of the restorer genes X and T involved in CMS¹ were determined in 12 German commercial chive varieties by test crossing single plants to male sterile, temperature‐insensitive genotypes [(S₁)xxT] for segregation analyses of offspring. Temperature sensitive genotypes [(S₁)xxT_] are able to produce pollen at higher temperatures, and should therefore be excluded from hybrid breeding to avoid self‐pollination of the maternal parent. The mean value of the frequency of the non‐restoring allele x in the populations examined was 0.62. The mean value of the allele t, which is responsible for the temperature insensitivity, was 0.9. As a consequence of these allelic frequencies about one‐third of all plants of the chive varieties examined were designated CMS₁ maintainer genotypes, leading to the production of temperature insensitive male sterile lines. The incidence of CMS₂ maintainers in the German varieties examined was nearly four times lower than CMS₁ maintainers. The mean value of the frequency of the non‐restoring allele _st2 involved in the CMS₂‐system was 0.29.     

Frequency and fertility restoration efficiency of Rf3 and Rf4 genes in Indian rice

Identification of new parental lines is crucial for developing ecology‐specific hybrids with ideal agronomic performance. We screened a total of 570 different ecology‐specific Indian rice varieties for the presence of fertility restorer genes, Rf3 and Rf4 using tightly linked markers DRRM Rf3‐10 and RM6100, respectively. Among these varieties, 13% carried Rf3Rf3/Rf4Rf4, 31% carried rf3rf3/rf4rf4, 6% carried Rf3Rf3/rf4rf4 and remaining 50% carried Rf4Rf4/rf3rf3 allelic combinations. A mini set of 40 varieties with variable allelic combinations of fertility restorer genes were testcrossed with WA and Kalinga‐based CMS lines. All the 80 F₁s were evaluated for spikelet fertility and fertility restoration ability. Rf3Rf3/rf4rf4 genotypes mostly behaved as partial maintainers or partial restorers. In contrast, rf3rf3/Rf4Rf4 genotypes were partial or effective restorers. However, double dominant genotypes showed better fertility restoration than the genotypes containing Rf3 or Rf4 individually. Some of the genotypes showed unexpected restoration pattern implying occurrence of other fertility restorer(s) apart from Rf3 and Rf4. The perfect restorers and maintainers identified in this study can be directly used in hybrid rice breeding.     

Development of a DNA marker for distinguishing CMS lines from fertile lines in rice (Oryza sativa L.)

The main objective of the present study was to identify mitochondrial DNA based marker, which can distinguish male sterile and fertile counterparts of the cytoplasmic male sterile (CMS) lines used in production of rice hybrids. Amplified fragment length polymorphism (AFLP) analysis in CMS lines: IR58025A & IR62829A and their respective maintainers: IR58025B & IR62829B identified a polymorphic DNA fragment of about 510 bp size that was present in both CMS (A) and absent in their maintainer (B) lines. Sequencing followed by database analysis of the polymorphic fragment indicated about 97% similarity with mitochondrial NADH gene subunits of rice, maize and wheat. Based on the variable sequence regions, a site specific primer pair (BF-STS-401) was designed. PCR analysis showed that BF-STS-401 could amplify a strong band of 464 bp size in CMS and a faint band of the same size in maintainer line. To act as a positive control and avoid possible errors in PCR, BF-STS-401 was multiplexed with a new primer pair (BF-STS-402), derived from mitochondrial atp9 subunit of rice, producing monomorphic amplification indiscriminately in both CMS and maintainer lines. Both the primer pairs in combination clearly differentiated CMS lines from their corresponding maintainer lines. This primer combination was validated in a set of diverse genotypes consisting of different sources of CMS lines, restorer lines, hybrids, varieties and mixed samples from private seed companies. Our results suggested that the multiplex primer pairs developed in this study can be effectively utilized to assess the genetic purity in commercial seed lots of CMS lines and hybrids of rice.     

Marker-assisted breeding for rf1, a nuclear gene controlling A1 CMS in sorghum (Sorghum bicolor L. Moench)

A study on marker-assisted selection (MAS) for the rf1 gene, which controls pollen sterility in the sorghum A1 cytoplasm, was conducted on the offspring population of two crosses between a maintainer line, BTx-622, and two sweet sorghum lines, BJ-299 and Lunen-2, to test the effectiveness of the MAS method and develop maintainer lines with sweet and juicy stalks and corresponding cytoplasmic-nuclear male sterility (CMS) lines. The simple sequence repeat marker Xtxp18 exhibited a high accuracy (95.098 %) for selecting recessive homozygotes for the rf1 gene. The segregation ratio matched the expected ratio calculated according to the reported genetic distance in the F₂ population of the two crosses used. Finally, four excellent maintainer lines/CMS line pairs (F₅/BC₃) with high stalk juice and stalk juice sugar contents were developed. The MAS method based on Xtxp18 for the sorghum rf1 gene could be used for hybrid breeding programs at a low cost in the future.     

EST辅助的甘蓝型油菜显性核不育AFLP标记转化

甘蓝型油菜显性核不育广泛应用于轮回选择和杂种优势利用,不育基因标记的开发与应用对于基因克隆和育种实践具有重要意义。基于AFLP标记SA12MG14的序列信息,从拟南芥整合数据库中,检索与标记序列同源的甘蓝型油菜EST,结合标记和EST序列设计特异引物,转化成新的SCAR标记。获得的SCAR标记S6B3,具有很高的检测稳定性,在回交群体Popu2上分析验证,结果与AFLP标记完全一致。该标记与不育基因相距0.3 cM,将其用于临保系同源的纯合型不育系选育,可有效提高育种工作效率。     

Identification and Inheritance of Fertility Restorer Genes for 'tour' CMS in Rapeseed (Brassica napus L.)

Eighteen genotypes of Brassica napus were crossed to a cytoplasmic male sterile (CMS) line of B. napus BO 15 carrying B. tournefortii cytoplasm (‘tour’ cytoplasm). Fourteen genotypes were found to be stable maintainers of the ‘tour’ CMS. Of the remaining four genotypes, GSL-1 and ‘Asahi-natane’ were found to be heterozygous and ‘Mangun’ and ‘Yudal’ were homozygous for the restorer gene. Analysis of the F₁ and F₂ progenies of (CMS) BO 15 בMangun’ and (CMS) BO 15 בYudal’ showed that fertility restoration is controlled by a single dominant gene. The availability of a number of stable maintainer lines and the simple inheritance pattern of fertility restorer gene makes ‘tour’ CMS a useful system for hybrid seed production in rapeseed.     

Identification and characterization of important sterile and maintainer lines from various genotypes for advanced breeding programmes of onion (Allium cepa)

Onion is one of the major vegetable crops in terms of production as well as consumption. In the current research, available onion genetic stock was evaluated to identify male-sterile lines and produce high-yielding F₁ hybrids for future breeding programmes. A mitochondrial DNA-based marker was mapped and correlated with phenotypic traits to isolate male-sterile plants. Based on the floral and pollen structure, nine putative male-sterile lines were identified. On the other hand, for nuclear marker identification at Ms locus, two sets of primers were used, one for Ms dominant allele and another for sterile and maintainer plants. Results revealed that 70% of open pollinated varieties (OPVs) possess plants with sterile cytoplasm coupled with genetic sterility at Ms locus, called sterile “A” line. Approximately 20% of plants in some genotypes were identified with normal (N) cytoplasm having recessive fertility gene at Ms locus, called maintainer “B” line. Based on the present findings, “A”, “B” and “R” (restorer line), future F₁ hybrid seed production systems in onion is discussed.     

Analysis of genic male sterility in Brassica oleracea

Summary The male sterility system MS-1 of Brassica oleracea was studied in order to elucidate if nucleo-cytoplasmic interactions determine this system. Crosses of male sterile MS-1 genotypes with heterozygous MS-5 genotypes gave fully fertile F₁ progenies. Selfing of seven F₁ plants resulted in five F₂ populations showing a 9:7 segregation ratio and two a 3:1 ratio for fertile and male sterile plants. Two F₂ progenies deviated from the expected 9:7 or 3:1 segregation ratios for fertile and male sterile plants. Thermosensitivity and distortion of the meiosis are suggested as the causal factors underlying the deviation of the segregation ratios. It was concluded that nuclear factors determine the male sterility in the MS-1 system, because the presence of a nucleocytoplasmic interaction in this system should have given only a 3:1 segregation ratio for fertile and male sterile plants in the F₂ generation.