Construction of Genetic Linkage Map of Bread Wheat （Triticum aestivum L.） Using an Intervarietal Cross and QTL Map for Spike Related Traits

Most often a genetic linkage map is prepared using populations obtained from two highly diverse genotypes. However, the markers from such a map may not be useful in a breeding program as these markers may not be polymorphic among the varieties used in breeding. For the past nine years, intraspecific maps have been gaining importance and such maps based on Swiss （PaiUard et al., 2003）, Japanese （Suenaga et al., 2005）, Australian （Chaimcrs et al., 2001） wheat varieties arc available. A map based on Indian wheat varieties however has not been reported. We constructed a genetic linkage map based on a cross between two Indian bread wheat （Triticum aestivum L.） varieties, Sonalika and Kalyansona. One hundred and fifty F2 individuals were analyzed for arbitrarilyprimed polymerase Chain reaction （AP-PCR）, random amplified polymorphic DNA （RAPD）, inter simple sequence repeats （ISSR）, Sequence Tagged Microsatelhte Sites （STMS）, Amplified Fragment Length Polymorphism （AFLP） markers, seed storage proteins and known genes. A linkage map was constructed consisting of 236 markers and spanning a distance of 3 639 cM with 1 211.2 cM for A genome, 1 669.2 cM for B genome, 192.4 cM for D genome and 566.2 cM for unassigned groups,     

Identification of QTL underlying the resistance of soybean to pod borer, <Emphasis Type="Italic">Leguminivora glycinivorella</Emphasis> (Mats.) obraztsov,and correlations with plant,pod and seed traits

Soybean (Glycine max L. Merr.) pod borer (Leguminivora glycinivorella (Mats.) Obraztsov) (SPB) results in severe loss in soybean yield and quality in certain regions of the world, especially in Northeastern China, Japan and Russia. The aim here was to evaluate the inheritance of pod borer resistance and to identify quantitative trait loci (QTL) underlying SPB resistance for the acceleration of the control of this pest. Used were the 129 recombinant inbred lines (RILs) of the F_5:6 derived population from ‘Dong Nong 1068’ × ‘Dong Nong 8004’ and 131 SSR markers. Correlations between the percentage of damaged seeds (PDS) by pod borer and plant, pod and seed traits that were potentially related to SPB resistance were analyzed. The results showed highly significant correlations between PDS by pod borer and plant height (PH), maturity date (MA), pod color (PC), pubescence density (PB), 100-seed weight (SW) and protein content existed. Soybeans with dwarf stem, light color of pod coat, small seeds, lower density of pubescence, early maturity and low content of protein seemed to have higher resistance to SPB. The correlated traits had potential to inhibit egg deposition and thereby to decrease the damage by SPB. Three QTL directly associated with the resistance to SPB judged by PDS at harvest were identified. qRspb-1 (Satt541–Satt253) and qRspb-2 (Satt253–Satt314) were both on linkage group (LG) H and qRspb-3 (Satt288–Satt199) on LG G. The three QTL explained 10.96, 9.73 and 11.59% of the phenotypic variation for PDS, respectively. In addition, 12 QTL that underlay 10 of 13 traits potentially related with SPB resistance were found. These QTL detected jointly provide potential for marker assisted selection to improve cultivar resistance to SPB. Guiyun Zhao, Jian Wang, and Yingpeng Han have equal contribution to the paper.     

Associations between 23 Quantitative Traits and 10 Genetic Markers in a Barley Cross

Associations of 23 quantitative traits and 10 genetic marker characters were examined in 63 chromosome-doubled lines (DH-lines) derived from the F₁- generation of a cross between an old and a modern spring barley variety. One fourth of the marker × trait combinations showed significant associations. More than two thirds of these associations were to earliness (heading date). Earliness was found to be controlled by two loci: the previously known eak locus and a new locus designated Ea. It is concluded that the associations of quantitative traits with the earliness loci were caused by pleiotropy. Associations were found between two absolutely linked C-bands on chromosome 3 and QTLs (quantitative trait loci) for lodging, straw diameter, and length of top internode of the straw. The three loci on chromosome 5, eak and the two linked powdery mildew loci, Mla9 and Mlk, were associated with a possible QTL for magnesium concentration in grain. Association to the C-band on chromosome 6 suggests QTLs for TGW (thousand grain weight), straw diameter and magnesium concentration in grain. Locus Estl on chromosome 3 was not associated with any of the quantitative traits.     

重组近交系群体定位绿豆抗绿豆象基因

绿豆象是对绿豆危害最严重的仓储害虫,检测和利用抗绿豆象基因是控制该害虫最经济有效的方法。利用高感豆象绿豆栽培种Berken和高抗豆象绿豆野生种ACC41亚种内杂交得到的重组近交系（RIL）群体及据此构建的1个包含79个RFLP分子标记的遗传图谱,通过对3个种植环境条件下收获的RIL群体进行2年的室内人工接虫鉴定,评价其抗绿豆象表现。QTL作图结果表明,在第9连锁群mgM213~VrCS161标记之间的1个QTL在2年3点试验中均被检测到,贡献率在74.05%~79.27%,是抗绿豆象主效基因。该QTL的加性效应值为负,表明来自父本ACC41的这个位点的等位基因可以提高绿豆对绿豆象的抗性。本研究结果对开展绿豆抗绿豆象育种以及抗绿豆象基因的精细定位和克隆有重要意义。     

Microsatellite markers associated with lint percentage trait in cotton, Gossypium hirsutum

Molecular markers associated with fiber development traits have the potential to play a key role in understanding of cotton fiber development. Seventeen SSRs out of 304 markers tested from MGHES (EST-SSR), JESPR (genomic SSR), and TMB (BAC-derived SSR) collections showed significant linkage associations (using a Kurskal-Wallis non-parametric test) with lint percentage QTL in a set of recombinant inbred cotton lines (RILs) segregating for lint percentage. The permutation test of these potential markers associated with lint percentage QTL(s) determined that 12 SSR markers have stable estimates, exceeding empirically chosen threshold significance values at or above α = 0.01. Interval mapping demonstrated that 9 SSRs with stable critical LOD threshold values at α = 0.01 have significant QTL effect. Multiple QTL-mapping (MQM) revealed that at least, two highly significant fiber development QTLs exist around regions TMB0471 and MGHES–31 (explained about 23–59% of the phenotypic variation of lint percentage) and around markers MGHES–31 and TMB0366 (accounted for 5.4–12.5% phenotypic variation of lint percentage). These markers, in particular fiber-specific EST-SSRs, might be the possible ‘candidate’ loci contributing for fiber development in cotton. BAC-derived SSRs associated with fiber trait are the possible markers that are useful for the identification of physical genomic contigs that contain fiber development genes. Several lint percentage trait associated SSR markers have been located to chromosomes 12, 18, 23, and 26 using deletion analysis in aneuploid chromosome substitution lines. Outcomes of the work may prove useful in understanding and revealing the molecular basis of the fiber development, and the utilization of these markers for development of superior cotton cultivars through marker-assisted selection (MAS) programs. I. Y. Abdurakhmonov and S. Saha contributed equally to the work     

大豆抗大豆食心虫机制研究初报

在抗虫鉴定的基础上,对大豆抗食心虫品种(系)的抗性机制进行了研究。发现豆荚硅元素含量高是抗虫的主要原因之一;豆荚表皮细胞呈近圆形突起、直径小或表皮细胞下小细胞层数多、表皮下有特长形细胞者;豆荚隔离层细胞呈短椭圆形、直径小、排列紧密者均有较强抗性。抗性与荚皮厚度、隔离层厚度及隔离层细胞排列方向无关。     

烟草六个重要性状的QTL定位

以烤烟台烟7号与白肋烟白肋21作为杂交亲本,后代自交衍生的127个F₂和F_2:3家系为材料,构建了全长3 483 cM包括26个连锁群、190个标记位点的烟草遗传连锁图谱。通过一年两地各3次重复的随机区组田间试验,测定烟叶烟碱、总氯、总钾、叶长、茎叶夹角、白粉病6个重要性状,采用混合线性模型的复合区间作图法定位QTL并分析其遗传互作效应。结果检测到2个烟碱相关QTL、2个总氯相关QTL、1个总钾相关QTL、4个叶长相关QTL、茎叶夹角和白粉病相关QTL各1个,其中6个加性效应QTL和4对加加上位性效应QTL。这11个基因位点遗传效应中除加性效应外,上位性效应也具有重要作用。     

利用Mudgo/武育粳3号F2群体分析水稻抗灰飞虱QTL

灰飞虱是我国水稻生产上的重要害虫。Mudgo是一个高抗灰飞虱的籼稻品种,对灰飞虱具有强的排驱性和抗生性抗性。利用Mudgo/武育粳3号F₂群体,构建了含有177个单株的F₂群体的遗传连锁图谱。该连锁图包含104个SSR标记和3个Indel标记,覆盖整个水稻基因组1 409.9 cM,每两个标记之间的平均距离为13.2 cM。采用改进的苗期集团筛选法对177个F_2:3家系进行了抗性鉴定,通过Windows QTL Cartographer 2.5进行复合区间作图分析,在第2、3、12染色体上分别检测到抗灰飞虱QTL Qsbph2b、Qsbph3d和Qsbph12a,分别位于标记RM5791~RM29、RM3199~RM5442和I12-17~RM333 1之间,单个LOD值分别为3.25、3.11和6.82,贡献率分别为17.3%、15.6%和35.8%,各QTL增强抗性的等位基因效应均来自Mudgo。其中Qsbph12a与标记RM3331和I12-17紧密连锁。结合表型鉴定的结果,Qsbph12a应为抗灰飞虱主效QTL,与该位点紧密连锁的标记可用于抗灰飞虱快速选择辅助育种。     

利用种子性状QTL定位高油玉米淀粉含量QTL

以普通玉米自交系8984与高油玉米自交系GY220为亲本组配得到284个F2:3家系群体,利用185个SSR标记构建玉米遗传连锁图谱。通过包含母体效应的种子性状QTL作图方法对玉米籽粒淀粉含量进行QTL定位和效应分析,共检测到7个与淀粉含量相关的QTL,分别位于第5,8,10染色体上,除qSTA8-3的遗传作用方式表现为加性外,其余QTL作用方式为部分显性。单个QTL贡献率为5.87%～10.93%,累计贡献率为53.37%。所有QTL的增效基因均来自普通玉米亲本8984。淀粉含量QTL qSTA5-2贡献率较大,可以作为进一步精细定位的主要目标QTL。     

利用种子性状QTL定位高油玉米蛋白质含量QTL

利用普通玉米自交系8984与高油玉米自交系GY220为亲本构建了284个F2∶3家系群体及含有185个SSR标记的玉米遗传连锁图谱。通过包含母体效应的种子性状QTL作图方法对玉米子粒蛋白质含量进行定位和效应分析,共检测到4个QTL,位于第5和第8染色体上。除qPRO8-2遗传作用方式表现为加性外,其余QTL作用方式均为部分显性。单个QTL贡献率为3.86%~5.17%,累计贡献率为18.54%。所有QTL的增效基因均来自高油亲本GY220。     

杂草稻种子休眠数量性状位点的定位

利用杂草稻与粳稻品种衍生的分离群体对控制种子休眠性的遗传基础进行了研究。检测到4个控制种子休眠性的QTL, 分别位于第1、第2和第6(2个)染色体上, 贡献率分别为7.8%、7.1%、5.5%和4.5%, 其中第2染色体上的QTL可能是一个新的控制种子休眠性的位点, 多项方差分析表明这4个位点的作用具有累加效应。种子发芽率与开花时间存在显著的负相关关系, 检测到的唯一一个控制抽穗期的QTL与位于第6染色体上的一个控制种子休眠性的QTL连锁或具有多效性, 这可能是造成其显著相关的主要原因。     

水稻基部伸长节间性状与倒伏相关性分析及QTL定位

利用珍汕97B/密阳46 RILs群体及其构建的连锁图谱,对水稻株高和基部Ⅰ、Ⅱ伸长节间性状与稻株抗倒伏能力进行相关分析,并对基部Ⅰ、Ⅱ伸长节间性状进行QTL定位,共检测到加性效应QTLs 16个、加性´加性互作33对。估算了每个QTL的加性效应值和每对加加互作的上位性效应值,比较了QTLs的基因组分布。在第1染色体短臂和第     

水稻品种IR24抗条纹叶枯病相关QTL的检测

为探明籼稻品种IR24是否携有新的抗条纹叶枯病基因,利用衍生于Asominori/IR24的重组自交系（RIL）群体和以Asominori为遗传背景IR24插入片段的染色体片段置换系（CSSL）群体,进行抗条纹叶枯病相关QTL的检测。利用疫区田间自然条件鉴定的方法,在RIL群体中共检测到4个控制条纹叶枯病的QTL,分别位于第3、5、7、11染色体上（qSTV3、qSTV5、qSTV7、qSTV11）, 其中qSTV3、qSTV7和qSTV11增强抗性的等位基因来自抗性亲本IR24。采用图示基因型比较法,在CSSL群体中将4个抗条纹叶枯病相关基因位点分别定位在染色体片段置换系CSSL4、L17、L39、L61、L62的IR24插入片段上。对比分析RIL群体和CSSL群体的分子连锁图谱,发现qSTV3所在的标记区间与CSSL17的IR24片段相吻合,qSTV7所在的标记区间与CSSL4的杂合片段、CSSL39的IR24片段相吻合,qSTV11所在的标记区间与 CSSL61的IR24片段以及CSSL62的杂合片段相吻合,表明确实存在这3个位点。与前人的研究结果相比较,发现位于第3染色体上的qSTV3区域存在抗刺吸性害虫的基因簇,是一个表达稳定的抗灰飞虱基因座;位于第7染色体上的qSTV7不同于已报道的抗性基因座,表明IR24携有新的抗性基因,这些基因不同于主基因Stvb-i,为防止广泛使用单一基因而造成的遗传脆弱性提供了新的抗性基因源,并且为利用分子标记辅助选择,聚合不同抗性基因培育抗性稳定的条纹叶枯病抗性品种创造了条件。     

普通菜豆籽粒大小与形状的QTL定位

普通菜豆是世界上最重要的食用豆类作物之一,其籽粒大小和形状与产量及外观品质密切相关。本研究以来自安第斯基因库的大粒品种龙270709和来自中美基因库的小粒品种F5910配置杂交组合,获得的F2分离群体分别在哈尔滨大田与北京昌平温室种植,对百粒重、粒长、粒宽、粒厚、长宽比和长厚比6个籽粒性状进行了相关性分析和QTL定位。相关性分析表明,百粒重与粒长、粒宽、粒厚、长宽比、长厚比5个衡量籽粒大小和形状的性状均显著正相关。利用基于完备区间作图方法的Ici Mapping 4.1进行QTL定位,哈尔滨环境下定位到38个与百粒重、粒长、粒宽、粒厚、长宽比、长厚比相关的QTL,表型贡献率介于2.39%~17.37%之间,分布在除第1染色体外的其余10条染色体上;北京昌平环境下定位到21个上述性状的QTL,表型贡献率介于5.92%~22.53%之间,分布在第1、第3、第6、第7、第8、第9和第11染色体上。其中,百粒重QTLSW7与SW7’,SW6.1与SW6’,粒长QTLSL6.1与SL6.1’,粒厚QTLSH11与SH11’在2个环境下的标记区间重叠或者重合,SW7、SW6.1、SL6.1、SW6’和SL6.1’的表型贡献率在10%以上。     

大豆重组自交系群体荚粒性状的QTL分析

利用大豆重组自交系soy01群体中的255个家系进行2年田间试验,采用两种作图方法,寻找一粒荚、四粒荚、每荚粒数等5个荚粒性状稳定的QTL。结果表明,利用区间作图法,2年共找到24个荚粒性状QTL,解释的遗传变异为5%~80%;利用复合区间作图法,2年共找到27个荚粒性状QTL,解释的遗传变异为4%~73%。利用复合区间作图法,2年找到2个重复出现、稳定的四粒荚QTL和2个每荚粒数QTL,为大豆荚粒性状QTL的精细定位和分子标记辅助育种提供了基础和依据。     

利用昆虫性诱剂防治大豆食心虫

为明确人工合成的大豆食心虫性诱剂对大豆食心虫的虫情监测和控制作用,为其在生产中的合理使用提供理论依据,进行了用人工合成性诱剂监测大豆食心虫田间种群动态调查,结果表明：2006年哈尔滨地区大豆食心虫的发生期大约为1个月,高峰期为8月7日至8月14日,与传统的目测惊蛾法调查的结果基本一致。4种不同田间诱蛾方式研究表明：水盆的诱蛾效果好于诱捕器,加入少量杀虫剂后诱捕器防治效果达到43．82％,而水盆加入少量杀虫剂后效果没有提高。2007年大豆食心虫性诱剂在哈尔滨地区开展大面积防治试验,防治效果为45．9％。2008年单用性诱剂＋诱捕器防效为50．0％,在诱捕器中加入少量杀虫剂防治效果达62．7％。性诱剂诱捕法可作为大豆食心虫田间虫情测报的一种适用工具。通过定点定期的田间诱捕观察,明确了大豆食心虫的发生动态,为适时防治提供铱据。在田间应用大豆食心虫性诱剂防治害虫时,诱捕器中加入少量杀虫剂是一个切实可行的方法,即提高了防虫效果,又不污染环境。     

Dissection of genetic effects of quantitative trait loci (QTL) in transgenic cotton

When alien DNA inserts into the cotton genome in a multicopy manner, several quantitative trait loci (QTLs) in the cotton genome are disrupted; these are called dQTL in this study. A transgenic mutant line is near-isogenic to its recipient, which is divergent for the dQTL from the remaining QTLs. Therefore, a set of data from a transgenic QTL line mutated by Agrobacterium-mediated transformation (30074), its recipient and their F1 hybrids, and three elite lines were analyzed under a modified additive-dominance model with genotype × environment interactions in three different environments to separate the genetic effects due to dQTL from whole-genome effects. Our result showed that dQTL had significant additive effects on lint percentage, boll weight, and boll number per square meter, while it had little genetic association with fiber traits, seed cotton yield, and lint yield. The dQTL in 30074 significantly increased lint percentage and boll number, while significantly decreasing boll weight, having little effect on fibre traits, while those from the recipient and three elite lines showed significant genetic effects on lint percentage. In addition, the remaining QTL other than dQTL had significant additive effects on seed cotton yield, fruiting branch number, uniformity index, micronaire, and short fibre index, and significant dominance effects on seed cotton yield, lint yield, and boll number per square meter. The additive and dominance effects under homozygous and heterozygous conditions for each line are also predicted in this study.