Comparisons on Genetic Diversity among the Isonuclear-Alloplasmic Male Sterile Lines and Their Maintainer Lines in Rice

Four sets of rice isonuclear-alloplasmic lines including 16 male sterile lines and their maintainer lines were analyzed by using 91 pairs of SSR primers to study the genetic diversity of nuclear genome and their relative relationships. A total of 169 alleles were detected in the 16 lines, with a frequency of polymorphic loci of 53.85% and an average number of alleles per locus of 1.8, and the average gene diversity was 0.228. Four sets of the isonuclear-alloplasmic male sterile lines shared 146 identical alleles, corresponding to 86.39% of the total alleles; meanwhile, there are 23 different alleles among the tested materials, being 13.61% of the total alleles. On average, 78.70% identical alleles and 21.30% different alleles of the total alleles were detected between the isonuclear-alloplasmic male sterile lines and their maintainer lines. There were 53.85% identical alleles and 46.15% different alleles of the total alleles among the homozygous allonucleus male sterile lines. The fingerprints were established for some male sterile lines and maintainer lines. All the materials tested were divided into three groups at the 0.2 genetic distance based on the cluster analysis. Eight lines of Huanong A and Huayu A (including Huanong B and Huayu B) were in the first group, four lines of Kezhen A (including Kezhen B) in the second group, and four lines of Zhenshan 97A (including Zhenshan 97B) in the third group. For the isonuclear-alloplasmic male sterile lines, the similarity coefficient between Y (Yegong) type and WA (wild abortive) type or between CW (Raoping wild rice) and WA type reached 87-98%.     

水稻同核异质不育系及其保持系核基因组的SSR分析

以4套共15份同核异质水稻雄性不育系和保持系为试验材料,应用随机分布于水稻12条染色体上的42对SSR引物,分析其核基因组的遗传多样性和亲缘关系。 在15份材料间共检测到63个等位基因,多态性位点百分率为4048%,平均每个位点的等位基因数为1.5个,平均基因多样性为0.18。4套同核异质不育系的平均相同位点为54.5个,占总等位基因数的86.51%,差异位点为8.5个,占13.49%。同核异质的不育系与保持系间具有平均77.78%的相同位点和22.22%的差异位点。同质异核不育系中则具有平均53.97%的相同位点和46.03%的差异位点。同时,获得了一些不育系和保持系的指纹图谱。根据不育系和保持系聚类分析图,在遗传距离为 0.22处划分为3群,第1群包括华农A和华育A不育系及其保持系共8份材料,第2群包括N9A、N10A和N11A等3份科珍2A材料,第3群包括N12A、N13A、N14A和N12 16B等4份珍汕97A同核异质系。同一套同核异质系基本上都优先聚类在一起,与其选育系谱一致。     

光照长度对三系杂交水稻不育系育性影响的研究

以珍汕97A、V20A、龙特浦A、博A为材料,通过暗室人工遮光处理,研究了它们的育性对光照长度的反应。试验结果表明,珍汕97A、V20A、博A在不同光照长度条件下,育性反应不同,龙特浦A的育性有明显反应,而且随着光照长度的增加,不育性愈好,呈幂函数关系。珍汕97A、V20A和博A没有明显的变化。     

白化转斑叶籼型水稻不育系高光A的创制及特征特性

以籼型保持系D57B为起始材料,利用300Gy的60Co-γ射线辐照干种子诱发突变,获得6叶前整株叶片全白而后叶脉白化其他部分转绿的突变体,经1次杂交和6次回交选育出一个携带白化转斑型叶色标记的籼型三系不育系高光A。该不育系白化转斑型叶色突变性状受单隐性核基因控制,1～6叶白化,6叶后呈白化斑叶,幼穗白化带绿;播始历期65d左右,属早籼早熟类型。与D57B相比,高光A植株稍矮且剑叶变长,有利于授粉(受精),提高杂种结实率和获得饱满的杂交种子,但种子萌发稍慢,其他农艺性状与D57B相仿。高光A具有高柱头外露率、强柱头生活力、长花时、小颖花张角、低闭颖率、对赤霉素敏感和强配合力等优良异交特性,杂种优势明显。高光A与杂交稻混播时,其幼苗竞争力弱。最后对高光A在三系杂交水稻生产中的应用前景作了讨论。     

水稻细胞质雄性不育系裂颖种子的穗上分布规律研究

对4个具有不同裂颖特性的水稻细胞质雄性不育系及其保持系的种子裂颖率和4个不育系种子裂颖粒在穗上的分布特点进行了研究。结果表明：保持系种子裂颖轻于不育系,不育系与相应保持系的种子裂颖率呈显著正相关。不育系种子裂颖与同穗颖花开放的迟早有关,开花迟,裂颖率高;强势穗裂颖轻于弱势穗;一次枝梗轻于二次枝梗;穗上部轻于中部,中部轻于下部;一次枝梗第6粒位裂颖最轻,第2粒位相对较重;强势粒轻于弱势粒。     

甜菜细胞质雄性不育系与其保持系游离脯氨酸含量的差异

以甜菜3个细胞质雄性不育系及其相应保持系为材料,对营养生长阶段叶片中的脯氨酸含量进行了研究.结果表明:在甜菜营养生长阶段的4个时期中,脯氨酸含量基本表现为保持系高于不育系.说明不育系和保持系在营养生长阶段生理生化代谢上已经存在差异.     

5种主要籼稻不育系细胞质的胞质效应研究

用龙特浦A、冈46A、Ⅱ-32A、新协黄A和粤泰A等应用于生产的5种主要类型细胞质雄性不育系及其保持系进行交叉配组,产生了20个二元系,研究了不同细胞质对二元系的育性、白叶枯病抗性、主要经济性状的影响.结果表明:除了红莲型细胞质外,野败型、冈型、印尼水田谷型、矮败型的保持关系相同,不同细胞质对白叶枯病的抗性没有显著差异,对主要经济性状的影响较小,但对异交性状具有一定影响,其中影响较大的为柱头外露率和开颖角度.讨论了多样性不育细胞质利用的途径.     

水稻KV型不育系细胞质效应的研究

 为了探索KV胞质的利用价值,用KVV41A、WAV41A、KV福伊A、WA福伊A与不同类型的恢复系配制18对组合,其F₁的六个农艺性状结果表明,两种不同胞质组合的农艺性状有明显差异,除个别组合少数性状外,总的趋势是KV型组合优于WA型组合。在相同细胞核遗传背景条件下,KV型胞质组合的杂种优势大于WA型胞质组合的杂种优势,这种效应是受细胞质支配的。通过内源激素检测进一步探明：KVV41A、WAV41A和V41B中的内源素IAA、GA_1+3+4+7含量有明显差异。V41B两种内源激素总含量最高,其次是KV型,最低的是WA型。V41B在整个幼穗发育过程中两种内源激素含量也是始终高于WAV41A和KVV41A,不育系的含量都较低,这可能是引起雄性不育的内因之一。而KVV41A中两种内源激素总含量和幼穗发育多数时段的含量介于WAV41A与V41B之间,可能是 KVV41A较WAV41A更容易被恢复的原因之一。     

水稻同核异质雄性不育系的细胞质遗传效应与细胞学研究

 对所构建的7种水稻同核异质雄性不育系进行细胞质遗传效应研究,包括主要生长特性和农艺性状、与恢复系测配的影响以及花粉发育的细胞学观察。结果表明,7种同核异质不育系的播始历期为81~83 d,剑叶长为25.10 ~29.40 cm,穗长为21.45 ~24.30 cm,株高为80.60 ~94.13 cm,每穗粒数在163.2~222.1。与恢复系辐恢838和绵恢725进行测配,结果表明用绵恢725配组时,各组合的生育期为113~115 d,剑叶长和剑叶宽2个性状与用辐恢838配组时类似。最主要的差别在株高、有效穗、每穗粒数、每穗实粒数、结实率和千粒重等几个性状。总体看株高明显下降,每穗粒数和实粒数显著增加,而结实率和千粒重多数不如用辐恢838配组的组合。用7种同核异质雄性不育系混合后与单一恢复系配组,在实践中是可行的。细胞学观察结果表明,同核异质雄性不育系花粉粒败育开始在单核期,92%以上为典败。花粉粒败育时,维管束的结构被彻底破坏。由此推断,所用的同核异质雄性不育系的败育应该同维管束的不正常发育有关,其败育机理应该是相同的。     

水稻不育系和保持系不同发育时期花药mRNA差异展示

 应用DDRT-PCR技术分析了粤泰不育系及保持系单核、二核及三核期的mRNA。不育系和保持系本身不同发育时期花药cDNA扩增带型相似,不育系和保持系同时期花药的cDNA扩增带型也很相似,说明大多数基因都是组成型表达的。在实验中共观察到24条差异带,通过与总RNA斑点杂交对部分差异带初步筛选,表明AGCK-20仅与不育系总RNA有杂交信号。     

水稻淡黄叶隐性标记不育系育种进展

概述了杂交水稻种子纯度鉴定的主要方法以及水稻淡黄叶隐性叶色标记不育系的特点和应用价值。自从2006年水稻淡黄叶隐性标记光温敏不育系安农标810S育成以来,以该不育系为标记基因供体,采用常规杂交转育的方法,初步育成了标泰S、标88S、标CS、1166S和H159A等多个淡黄叶标记新不育系。介绍了这些不育系的主要特性及所配部分组合的表现。     

Genetic Mechanism of Dominant Earliness in Kefeng A, a New Rice Cytoplasmic Male Sterile Line

Kefeng A is an early maturing indica cytoplasmic male sterile (CMS) line of rice. Combinations derived from Kefeng A and late maturing indica restorer lines showed dominant earliness to various extents. To understand the genetic basis of dominant earliness, the genotype of photoperiod-sensitive genes in Kefeng A was analyzed using a complete set of heading time near isogenic lines (NILs) EG0 to EG7, ER, LR, T65, T65Eb, T65Ebm, T65m, NIL(Hd1) and NIL(Hd4). Results indicated that Kefeng A contained two dominant photoperiod-sensitive alleles E1 and Se-1u on E1 and Se-1 loci, respectively, and the genotype of photoperiod-sensitivity genes for heading time in Kefeng A was E1E1e2e2E3E3Se-1uSe-1uEf-1Ef-1. Based on the detected heading time genotype, in combination with the heading time of Kefeng A and the early maturing phenomenon in its derived F1 hybrids, it is speculated that Kefeng A might carry a dominant inhibitor gene Su-E1 for the dominant photoperiod- sensitive gene E1, and a recessive inhibitor gene i-Se-1 for another dominant photoperiod-sensitive gene Se-1. The reason why F1 hybrids from Kefeng A exhibited early maturing was hereby analyzed and the breeding value of dominant earliness related genes in Kefeng A was discussed.     

标记两用核不育水稻M2S的花药培养及遗传分析

利用花药培养技术对籼型两用核不育水稻的杂种F1进行花药培养,获得了大量的绿苗,从组合M2S / 培矮S中选育出一批带淡绿叶标记的籼型两用核不育DH品系,选择部分DH系进入人工气候箱鉴定其光温反应特性,结果表明DH系之间的光温反应特性差异较大。通过亲本、F1、F2和BC1世代的遗传研究表明,两用核不育基因从感光的晚粳农垦58S转导至弱感光的籼稻M2S后,表现为由2对主基因控制,微效基因的修饰作用明显;淡绿叶性状由1对基因控制,两用核不育基因与淡绿叶基因之间不存在连锁。还对两用核不育基因的遗传分析条件、花药培养效果及其在两用核不育系选育中的作用进行了讨论。     

粳稻光(温)敏核质互作不育系(SA)的育性和可恢复性研究

连续3a的分期播种试验表明，聚合光（温）敏核不育系S和核质互作不育系A的不育基因转育而成的粳稻光（温）敏核质互作不育系SA的育性对光温反应迟钝，在长日高温、适温、低温和短日适温、低温下其育性都稳定不育；SA花粉败育类型表现为长日下以典败为主，短日下典染共存，且随着日长的变短和温度的降低，染败花粉有增加的趋势。可恢复性试验表明，不同的恢复系对SA的恢复能力强弱不同，SA的可恢复性一般介于亲本S和A的可恢复性之间。     

Development of Novel Cytoplasmic Male Sterile Source from Dongxiang Wild Rice (Oryza rufipogon)

This study was conducted to develop and characterize a novel cytoplasmic male sterile(CMS)source which was identified from Dongxiang wild rice(Oryza rufipogon)by crossing Dongxiang wild rice as female with Zhongzao 35,an indica inbred variety,as male and continuous backcrossing with Zhongzao 35.Observation under optical microscope manifested that this novel CMS belonged to typical abortion type with less pollen compared with wild abortive type cytoplasm(CMS-WA).Sequential planting showed that this novel CMS has complete and stable male sterility.Testcross experiment showed that all the 24 tested materials including maintainer and restorer lines of CMS-WA and Honglian type cytoplasm(CMS-HL)and other indica inbred varieties are the maintainers with complete maintaining ability,suggesting that this novel CMS has fertility restoration totally different from CMS-WA and CMS-HL and belongs to a novel type of CMS.So far,we only discovered a unique fertility restoration source for this novel CMS.Inheritance analysis showed that the fertility restoration of this CMS was governed by three pairs of independent dominant genes.Prospect for application of this novel CMS system in hybrid rice breeding was also discussed.     

华南晚籼夜公细胞质（Y型）雄性不育系的选育

由华南晚籼迟熟品种夜公细胞质育成了Y型不育系,证明华南晚籼迟熟品种中存在着雄性不育细胞质。Y型雄性不育细胞质效应优于野败,其不育系表现全不育,不育性稳定,恢保关系与野败相似,生育期遗传多样化,配合力强,已由其育成一批强优组合。由Y华农A育成的华优86和华优桂99 表现高产稳产、米质优良、抗病性强,表明Y型不育系是可以开发利用的新型细胞质雄性不育系。     

4个新育成籼型雄性不育系的生育特性与柱头活力观察

通过对4个新育成的籼型雄性不育系的生育特性与柱头活力进行系统观察,结果表明：4个新育成的不育系农艺性状优良、育性稳定,套袋无自交结实情况。其中412A柱头外露率最高达89．20％,558A、698A柱头外露率与对照II-32A相当,也都高于83％。412A的柱头活力保持时间最长且柱头活力下降较慢。通过观察研究认为,4个新不育系其各项育种指标较为完善,主要农艺性状优于II-32A,具有一定的应用价值。     

我国三系杂交稻主要不育系的微卫星标记多样性和遗传结构分析

选取均匀分布在水稻12条染色体上的48对SSR引物,对28份我国杂交水稻主要不育系进行了多样性和遗传结构分析。 在所分析的48个位点中,多态性位点41个,多态性位点百分率（P）为85.4%;每1个位点平均等位基因数（A）为3.5,变幅2～6个;平均基因多样性指数（He）和平均多态性信息含量指数（PIC）分别为0.40和0.36。AMOVA分析表明,不育系遗传变异主要存在于各选育时期内,时期间的遗传变异仅占总变异的3.3%,且未达到显著水平。基于模型的遗传结构分析表明,我国三系杂交稻主要不育系多数含有相近血缘,背景单一。     

Influence of Genetic Drift of Restoring Gene (Rf) on Seed Purity of Yuetai A, a Honglian-Type Cytoplasmic Male Sterile Line in Hybrid Rice

The seed samples of Yuetai A, a Honglian (HL) type cytoplasmic male sterile (CMS) line in hybrid rice were investigated to assess the seed purity and to analyze the cause of off-type plants by imitating the biological contaminant to Yuetai A in Nanjing, Jiangsu Province and Lingshui, Hainan Province during 2004–2006. The seed impurity of Yuetai A mainly resulted from the genetic drift of restoring fertility gene (Rf) after biological contamination but not from its sterility unstability. All of the ten maint...     

温敏核不育基因在籼型三系遗传背景下的育性表达

用3个温敏核不育系培矮64S、6311S和360S与7个籼型质核互作型水稻雄性不育系及相应的保持系、3个恢复系配组,观察了51个组合的F1、19个F2及6个BC1的育性表现。结果表明：培矮64S温敏核不育性状由2对隐性基因控制,具有对质核互作型雄性不育系育性的强恢复基因;6311S温敏核不育性状由1对隐性基因控制,同时具有1对弱恢复基因;360S温敏核不育性状由1对隐性基因控制,但没有恢复基因。进一步利用4个细胞质雄性不育系/6311S组合F2群体中4个温敏核不育株与5个细胞质雄性不育系CMS配组,研究了杂交F1的育性,表明在可育细胞质背景下,三系恢复基因对温敏核不育基因的表达没有影响;在不育细胞质背景下,三系恢复基因是温敏核不育基因表达的关键。由此提出了选育不育细胞质背景的光温敏核不育系和温敏核不育背景的质核互作型不育系的策略。