选育甘蓝型春油菜波里马不育胞质三系杂种的研究

在青海春油菜生态区的田间试验结果表明,长江中游的单,双低半冬性甘蓝型油菜品种资源,绝大部分能正常生长适时成熟,这些品种资源与波里马细胞质雄性不育材料测交和连续回交,大部分半冬性品种的回交后彻底不育,而春性品种的后代出现微粉。半冬性品种转有的不育系或恢复系与春性品种转育的恢复纱或不育系配制的杂种优势明显。今后春油菜区在马不育胞质三系杂种的选育,应用长江中游双低半冬性品种（系）转育的不育系与加拿大和欧     

利用人工合成甘蓝型油菜创建油菜新种质

为了拓宽甘蓝型油菜的遗传基础,从四川、重庆、云南和西藏部分地区采(收)集了一批白菜型油菜、白菜和白花芥蓝地方品种,包括一部分白菜型油菜野生种和半野生种,通过远缘杂交,人工合成了一批甘蓝型油菜新材料。这批新材料具有丰富的遗传变异,主要包括特长角、大粒、多分枝、矮秆、黄籽、白花、抗病等重要遗传类型,部分材料具有重要的育种及研究利用价值。     

Assessing the relationship between endosperm type and grain yield potential in sorghum (Sorghum bicolor L. Moench).

Sorghum hybrids with waxy endosperm (either homozygous or heterozygous waxy) have lower grain yield potential compared to non-waxy endosperm hybrids. The cause of this yield reduction is not known. From a genetic perspective, the yield reduction could be due to pleiotrophy or genetic linkage between the wx locus and other loci that influence grain yield. The specific cause of the relationship is important because an effective breeding program can alleviate the problem if it is due to linkage. The objective of this study was to determine whether linkage or pleiotrophy is causing the negative relationship between grain yield and waxy endosperm. From each of two F₂ breeding populations segregating for waxy endosperm, between 40 and 50 inbred lines were derived, with equal numbers of waxy and non-waxy endosperm lines. No selection for yield was practiced during the development of these lines. The lines from these two populations and a set of testcross hybrids (derived from one population) were evaluated in four environments in Texas from 1998 to 2000. Across all tests and environments, the combined yield of the waxy genotypes was 17% lower than non-waxy genotypes. While yields were lower in waxy genotypes, analysis of the individual inbred lines and hybrids revealed that several waxy inbred lines were not statistically different from the best non-waxy inbreds. These results imply that selection of high yielding waxy genotypes is possible, but a significant breeding emphasis on their development is required to effectively identify those genotypes.     

我国春油菜遗传育种研究进展

我国春油菜主要分布在西部高海拔地区和北部高纬度地区,单产和含油量高于全国平均水平,种植面积约占全国油菜总面积的1/10。本文主要综述了近些年我国春油菜在种质资源创新、重要农艺性状相关基因（QTL）定位、新品种选育等方面的主要研究进展,指出了目前生产上存在的主要问题,并对春油菜育种前景进行了展望,为今后春油菜遗传育种提供参考。      

Clubroot resistance introgression in interspecific hybrids between Raphanus sativus and Brassica napus

Clubroot is a prevailing soil-borne disease affecting rapeseed production worldwide.However,few clubroot resistant rapeseed accessions were available for breeding.Identification and introgression of new clubroot resistant genes from closely related species by distant hybridization is an effective strategy.In the present study,9 radish(Raphanus sativus L.,2n=18,RR)lines resistant to Plasmodiophora brassicae pathotype 4 were used as donors to transfer clubroot resistance into a susceptible rapeseed(Brassica napus L.,2n=38,AACC)line by distant hybridization combined with embryo rescue.Nine intergeneric crosses were made but only 1(411×93039)produced F1 plants both from embryo rescue and natural seed-setting.Authenticity of triploid F1 hybrids(2n=28,ACR)were verified by flower color,cytological observation and molecular marker analysis,and 2 genuine F1 hybrids were identified.After chromosome doubling,these synthetic allohexaploid plants(2n=56,AACCRR)became partially fertile(pollen viability rate=35%)and were backcrossed with rapeseed parent to generate a BC1 population(2n=47,AACCR).Totally 178 BC1 plants were obtained,of which the majority(96.1%)were resistant to clubroot.These backcrossing progenies could be used for the breeding of new rapeseed varieties resistant to clubroot.     

Improvement of bacterial blight resistance of hybrid rice in China using the Xa23 gene derived from wild rice (Oryza rufipogon)

A novel bacterial blight (BB) resistance gene, Xa23, identified from Oryza rufipogon was introgressed into three popular restorer lines (Minghui63, YR293 and Y1671) for wild abortive cytoplasmic male sterility by marker-assisted backcross breeding approach in combination with artificial inoculation and stringent phenotypic selections. The three derived BB resistant restorer lines (Minghui63-Xa23, YR293-Xa23 and Y1671-Xa23) and their hybrid combinations with Zhenshan97A (Shanyou63-Xa23), NongfengA (Fengyou293-Xa23) and Zhong9A (Zhongyou1671-Xa23) demonstrated similar BB resistance spectrum as the donor parent, CBB23 (B). The newly developed BB resistant restorers and their derived hybrids were identical to their respective original versions for agronomic traits especially under disease free condition. However, under severe disease condition, the three BB resistant restorer lines exhibited significantly higher grain weight and spikelet fertility as compared to the respective original restorer lines thus further resulting in BB resistant hybrids with significantly higher grain yields than their respective popular original hybrids. The results indicated that the Xa23 gene could completely express its dominant broad spectrum resistance in different backgrounds of both restorer and male sterile lines across different growth stages, suggesting its immense breeding value in BB resistance improvement for hybrid rice. Moreover, a reasonable utilization and deployment of Xa23 gene for efficient control of BB disease in hybrid rice production was recommended.     

2001-2009年国家冬油菜区域试验参试材料分析

2001至2009年参加区域试验(以下简称区试)的595份品系申报材料分析结果表明:参试品系数量增长6倍,申报单位数量增长7.5倍.参试品系由常规种为主转变为以杂交种为主,杂交种比例均值达77.90%.育种中使用的授粉控制系统由细胞质不育系为主转变为细胞质和细胞核不育系兼用,2003年后利用核不育系选育的品种数量与细胞...     

中国部分冬、春小麦品种(系)1BL/1RS易位系的A-PAGE检测

为了在春小麦品质育种中合理利用种质资源,采用酸性聚丙烯酰胺凝胶电泳(A-pAGE)对来自中国部分冬、春麦区的106份小麦品种和132份品系进行1BL/1RS易位系检测.结果表明,供试材料中共有63份为1BL/1RS易位系,频率为26.5%.其中106份品种中30份为1BL/1RS易位系,占供试品种的28.3%,且不同麦区之间1BL/1RS易位品种的频率不同.东北春麦区未发现1BL/1RS品种;西北春麦区和新疆冬春麦区易位系频率较高,均为50%;北部春麦区和青藏高原冬春麦区易位系频率较低,分别为16%和25%;冬麦区1BL/1RS易位系频率也较高(44%).132份品系中,33份品系为1BL/1RS易位系,占供试品系的25%.     

基于3个甘蓝型春油菜Pol CMS的优良恢复系选育

为选育出优良的恢复系父本,能够与春油菜区优良的春性甘蓝型油菜波里马细胞质雄性不育系（Pol CMS）配制出强优势杂交组合,先利用简化基因组测序技术（SLAF-seq）开发3个不育系和118个恢复系的SNP标记,对材料进行聚类分析,根据父母本花期相遇原则,从每一类选取数量不等的恢复系,共40个恢复系,分别与3个不育系采用NCⅡ设计配制120个杂交组合,分别进行配合力效应、杂种优势及双亲遗传距离与杂种表现的相关性分析。结果表明：遗传聚类将121份甘蓝型油菜资源分为5大类,大多数相同类型的品系被聚在了同一类,3份不育系均被聚在了第Ⅴ类;43份亲本的一般配合力（general combining ability,GCA）的变化范围为-20.78～30.42,恢复系R83、R107和R13的GCA较大,不育系GCA较大的为S3（105A）,特殊配合力较大的组合有S3×R13、S1×R48、S3×R11、S2×R89;组合S3×R13的产量超标优势和超亲优势最大,分别为37.12%和42.52%。遗传距离与单株产量呈极显著正相关,相关系数为0.390。与3个不育系组配的杂交组合中,产量排名前20位的亲本恢复系大部分来自和不育系遗传距离较大的Ⅰ类,并且在春油菜区大面积推广的品种,如青杂2号、青杂7号、青杂9号、青杂12号,均为被聚在Ⅰ类的恢复系与不育系S3（105A）组配的杂交种。因此认为,（S×Ⅰ类恢复系）组配模式可以获得强优势甘蓝型春油菜杂交组合。该研究不仅为后续甘蓝型油菜杂交种选育提供了亲本选择的分子依据,也将促进春油菜区的杂交育种进程。     

Susceptibility of potato varieties and advanced breeding lines (Solanum tuberosum L.) toPhytophthora infestans (Mont.) de Bary in greenhouse screenings

Late blight (Phytophthora infestons (Mont.) de Bary) has re-emerged as an important pathogen of the cultivated potato (Solanum tuberosum subsp.tubero-sum L.) in North America. The purpose of this study was to evaluate the relative susceptibility of potato germplasm in the greenhouse in order to initiate a breeding program for resistance to the US-8/A2 mating type which is the more aggressive and prevalent strain of late blight. Whole plants of 147 cultivars and breeding lines were evaluated. Percent plant area infection was visually assessed. Seven days after inoculation, infection ranged from 0 to 100% and the overall mean was greater than 50%. Two-thirds of the cultivars and breeding lines tested were very susceptible to the US-8 genotype. The highest resistance was identified in the somatic hybrids betweenS. tuberosum andS. bulbocastanum and their backcross derivatives. Pike and Snowden were less susceptible than the other North American cultivars. Zarevo was most resistant among the European cultivars. Seven of the advanced breeding lines were equivalent to Zarevo in infection levels. The host plant resistance identified among the material tested in this study can be used by breeding programs to develop improved cultivars with resistance to US-8 genotypes of late blight.     

西南地区普通小麦1BL/1RS易位系的DArT分子标记鉴定

为了准确了解小麦品系中1BL/1RS易位系的存在,利用7 000多个DArT分子标记(Diversityarrays technology,多样性微阵列技术)对87个普通小麦品系进行扫描,总共获得1 750个稳定的多样性的分子标记(P>80)。这些标记的多态性信息含量指数(PIC)的范围是0.03～0.5,平均值为0.35(P>80)。根据DArT标记的可整合性,利用1B染色体上的DArT数据进行主坐标分析(Principal-Coordinates Analysis,PCoA),可以把实验材料划分为两个群,并且确定一个群是由1BL/1RS易位系组成,另一个群由非1BL/1RS易位系组成。同时,利用非加权组平均法(Unweighted pair-group method with arithmetic means,UPGMA)进行聚类分析,调查了材料之间的遗传关系,结果显示,实验材料同样聚集为两个群,一个群由1BL/1RS易位系组成,包含两个亚群;另一个群由非易位系组成,包含六个亚群。研究证实,DArT标记不仅可以调查小麦全基因组的遗传多样性,而且利用它的可整合性能够准确鉴定研究材料中的1BL/1RS易位系。     

Evaluation of CIMMYT conventional and synthetic spring wheat germplasm in rainfed sub-tropical environments. I. Grain yield

Hexaploid spring wheat (Triticum aestivum L.) germplasm from CIMMYT's breeding program in Mexico has assisted wheat improvement in Australia, particularly in the north-eastern region where terminal drought frequently reduces grain yield. A total of 273 conventional hexaploid and derived synthetic hexaploid spring wheats from CIMMYT, along with 15 locally adapted Australian cultivars (Oz lines), were evaluated for grain yield over four years in a total of 27 environments in Australia's north-eastern wheat region. The CIMMYT conventional spring wheats were from a Seri/Babax recombinant inbred line population (SB lines), elite entries from an International Adaptation Trial (IAT lines) introduced to Australia between 1999 and 2004 and from CIMMYT screening nurseries introduced to Australia in 2004–2005 (SW lines). Synthetic wheats (SYN lines) were also from these nurseries as well as from a separate program of synthetic wheat introductions to Australia over 2001–2004.     

杂交水稻品质改良的遗传基础和途径

阐述了杂交稻稻米品质的特点以及各品质性状的遗传特征 ,指出选育优质杂交组合必须以收集优质亲本资源为前提 ,并通过杂交选育、回交选育以及群体改良等手段加以改进 ,在创造出更为优良的亲本 (不育系与恢复系 )之后 ,采用优质亲本与中等或中等偏上米质的亲本配组 ,可以选育出适合广大群众所需要的普食型高产优质组合 ;采用优质亲本配优质亲本 ,可以选育出符合特殊消费和出口要求的高档优质组合     

青海省几个主要春性甘蓝型油菜杂交种的SSR分析

为了探明青海省主要甘蓝型油菜品种的遗传变异,建立准确高效的种子纯度鉴定方法,本研究选取5个青海省甘蓝型油菜主栽品种,利用140对简单重复序列(Simple sequence repeat,简称SSR)引物对其进行分子标记分析,从中筛选出26对能清晰扩增出多态性主带的引物,进一步对包括这5个品种及其中4个杂交品种的7个亲本系进行扩增后,经6%聚丙烯酰胺凝胶电泳分离和带型分析,成功构建出5个青海省甘蓝型油菜主栽品种及其中4个杂交种亲本系的指纹图谱,并鉴定出了这4个杂交种的共显性标记。这些标记不仅可用于亲本材料和杂交品种真伪的鉴别,还可为杂交种纯度的鉴定提供可靠方法,对亲本知识产权的保护及杂交种推广具有重要的意义。     

Characterisation of starch during germination and seedling development of a rice mutant with a high content of resistant starch

To acquire a better understanding of whether RS influences the dynamics of in vivo starch digestion and seed vigour, the high-RS rice mutant RS4 (RS ca. 10%) and the wild type R7954 were used to investigate total amylase activity, seedling vigour, starch content and starch granule structure during germination. RS4 exhibited similar seed vigour to R7954. Amylose and amylopectin in R7954 showed synchronous degradation throughout the whole process, while amylopectin was hydrolysed significantly faster than amylose in RS4 during the earlier germination stages. The starch residues of RS4 after germination (GD) lost endotherm peaks and showed a special X-ray diffraction pattern with only two peaks at around 16.90° and 21.62°, probably due to remnants of amylopectin and its tight crosslinking with the cell wall. The remaining starch after 10 GD, primarily amylopectin may make a critical contribution to total resistant starch content. These results indicated that RS had no negative impact on seed vigour in rice lines, although RS cannot be hydrolysed by α-amylase from human and animal in vitro. By appropriately increasing the special amylopectin fraction, a new breeding programme of high RS crops and improvement in the eating quality of high RS rice varieties might be achieved.     

Discriminating power of selected physical properties of seeds of various rapeseed (Brassica napus L.) cultivars

In this study, the seeds of open-pollinated winter rapeseed cultivars, hybrid winter rapeseed cultivars, open-pollinated spring rapeseed cultivars and hybrid spring rapeseed cultivars were investigated. The physical, optical, mechanical, geometric and image texture properties of rapeseeds were compared. Statistical models were developed based on the analyzed parameters to discriminate between seed groups. Most parameters effectively discriminated between cultivars of winter and spring rapeseed, including true density, porosity, L*, a*, b*, and spectral values at 400 nm, 470 nm, 500–530 nm, 560–620 nm, 640–650 nm and 690 nm. Four homogeneous groups were identified based on linear dimensions: F (surface area), S (width) and shape factors W₆ (circularity ratio), Rb (Blair-Bliss coefficient) and W₁₃ (roundness). No statistically significant differences in the mean values of hardness or area under the force-displacement graph were observed between seed groups. The model developed based on image texture variables from channel Y (luminance) was characterized by the highest discrimination accuracy of 82–87%. The experimental groups were classified with 89–92% accuracy in the model combining the best variables from each group of physical parameters. Total classification accuracy in neural networks reached 75% for a validation set comprising geometric properties and 91–92% for a validation set containing physical characteristics.     

通过分子标记估算遗传距离预测甘蓝型油菜的杂种优势

用甘蓝型油菜4个恢复系、3个保持系及其相应的12个F1代共19份材料，研究SSR和SRAP两种分子标记方法估算的遗传距离与油菜重要性状杂种优势的关系。结果发现，在4个恢复系和3个保持系中，45对SSR引物共扩增出87条多态性条带，25对SRAP引物共扩增出131条多态性条带。基于SSR标记估算的遗传距离与产量杂种优势的相关系数为0.423,决定系数为0.179。基于SRAP标记估算的遗传距离与产量杂种优势的相关系数为0.654 （达到0.05显著水平），决定系数为0.428。基于SSR和SRAP混合数据计算的遗传距离与小区产量杂种优势的相关系数为0.642（达到0.05显著水平），决定系数为0.412。表明SRAP标记对产量杂种优势预测的效果要显著高于SSR标记预测的效果，是目前为止报道的通过鉴定亲本遗传多态性预测油菜杂种优势最为有效的分子标记手段，可作为油菜杂种优势预测的一种有效辅助方法。     

Development ofNew InDel Marker to Detect Genotypes of Conferring Fertility Restoration of BT-Type Cytoplasmic Male Sterility inRice简

Restorer line breeding is an important approach to enhance the heterosis and improve the yields of japonica hybrid rice. To improve the selection efficiency of restorer lines for BT-type cytoplasmic male sterility (CMS) in japonica rice, a functional marker InDel-Rf-1a based on the difference of nucleotide sequence in Rf-1a locus between BT-type CMS lines and restorer lines was developed to detect the genotypes of different rice materials. Conventional indica rice varieties, restorer and maintainer lines without 574 bp deletion could restore the fertility for BT-type CMS in japonica rice. By contrast, most conventional japonica rice varieties except Aichi 106 and Yijing 12, with genotype of rf-1arf-1a showed the 574 bp deletion maintained sterility for BT-type CMS lines. To further verify the effect of genotyping detection in Rf-1a locus, this marker was also used to amplify the genomic DNA in different japonica rice restorer lines, CMS lines, hybrids and F₂ segregation population, and three genotypes in Rf-1a locus could be distinguished distinctly. Therefore, the marker InDel-Rf-1a could be widely used for genetic identification and marker-assisted selection (MAS) in breeding japonica restorer lines.     

Interspecific somatic hybridization betweenSolanum tuberosum L. andS. bulbocastanum dun. as a means of transferring nematode resistance

Interspecific somatic hybrids were produced between tetraploidSolanum tuberosum and a nematode-resistant accession of the diploid speciesSolanum bulbocastanum by protoplast fusion. Hybrid cells were selected using dual fluorescent labeling of protoplast preparations prior to fusion. Hybridity of regenerated plants was confirmed with a combination of morphological assessment, chromosome counting and isozyme analysis. Somatic hybrids had the same level of resistance to infection by race 1 of the nematodeMeloidogyne chitwoodi as theS. bulbocastanum parent used in the fusion. Some of the somatic hybrids were fertile as females when crossed with tetraploidS. tuberosum breeding lines. Thus, these hybrids can be used in a potato improvement program to incorporate a valuable pest resistance     

Emergence and plant stand of pregerminated true potato seed in warm climate

Pregermination of true potato seeds obtained from open pollination of breeding lines and F₁, hybrids improved the emergence and stand in a warm climate. Considerable differences in emergence existed within the breeding lines and F₁ hybrids. With proper selection of breeding lines and pregermination of seeds, it would be possible to obtain a desirable plant stand in a warm climate.