云南小麦品种(系)株高和粒重相关功能基因的KASP标记检测

利用矮秆基因Rht-B1、Rht-D1和千粒重功能基因TaCwi-A1、TaGW2-6A、TaSus2-2B的KASP标记,对云南省育成的42份小麦品种(系)进行单倍型检测,旨在筛选出含有目标基因的优异小麦种质,为云南省小麦产量相关性状的遗传改良提供材料和方法。结果表明,供试材料的株高基因组成分为5种类型,分别为Rht-B1a/Rht-D1a(40.48%)、Rht-B1a/Rht-D1b(23.81%)、Rht-B1a+197bp/Rht-D1a(4.76%)、Rht-B1b/Rht-D1a(28.57%)、Rht-B1b/Rht-D1b(2.38%)。供试材料中TaCwi-A1基因TaCwi-A1a高粒重单倍型的分布频率为42.86%,TaGW2-6A基因Hap-6A-A高粒重单倍型的分布频率为38.10%,TaSus2-2B基因Hap-H高粒重单倍型的分布频率为71.43%。5份品种(系)为3个千粒重基因的TaCwi-A1a/Hap-6A-A/Hap-H高粒重单倍型组合,频率为11.90%。研究表明,云南小麦品种(系)产量相关性状具有较好的遗传改良潜力。     

小麦矮杆基因的分子检测及遗传效应研究

利用矮秆基因Rht-B1b、Rht-D1b和Rht8的特异性分子标记对202份普通小麦材料进行了分子检测,连续两年观测了供试材料的重要农艺特性,分析了不同矮秆基因的遗传效应。结果表明:在202份供试材料中,22份供试材料含有基因Rht-B1b,分布频率为10.89%;基因Rht-D1b、Rht8和不含3种矮秆基因的材料分布频率分别为73.76%、65.84%和6.93%,其中有12份材料含基因Rht-B1b+Rht8,有104份材料含Rht-D1b+Rht8,分布频率分别为5.94%和51.43%。矮秆基因对农艺特性的影响不同。3个矮秆基因均可以显著地降低株高,其降秆效应分别为Rht-D1bRht-B1bRht8,就基因组合而言,降秆效应则是Rht-D1b+Rht8Rht-D1bRht-B1b+Rht8Rht-B1bRht8,说明矮秆基因具有累加效应,同时含有2个矮秆基因要比只含有其中1个矮秆基因株高更低。矮秆基因在有效分蘖、穗长、小穗数和穗粒数等方面不存在显著差异,但矮秆基因对有效分蘖有一定的负效应,有利于穗长和穗粒数的增加。基因Rht8可以显著提高千粒重,而Rht-B1b和Rht-D1b对千粒重存在一定的负效应。试验中含有基因Rht-D1b和Rht8的部分材料在农艺性状中表现良好,应进一步加以利用。     

河北省小麦重要农艺性状的KASP标记检测

为了将分子标记技术尽快应用到小麦育种工作中,利用高通量KASP (Kompetitive allele specific PCR)标记检测了河北省153份审定小麦品种的光周期、春化、株高、粒重、穗发芽、抗旱和抗病相关基因。结果表明在Ppd-B1和Ppd-D1光周期位点分别检测到24个和5个光周期不敏感品种。Vrn-D1b春化基因占比45.1%,Vrn-A1位点3个标记检测春化基因占比分别是0.7%,6.5%和6.5%。株高基因中Rht-B1位点2个标记检测矮杆基因占比分别是41.2%和7.2%,Rht-D1b矮杆基因占比35.9%。TaSus2-2B、TaGs3-D1、TaCKX-D1、TaGASR7-A1、TaCwi-4A、TaCwi-5D、TaMoc-A1和TaTGW6是与粒重有关的8个基因,优异等位变异占比分别是22.9%、58.8%、57.5%、7.2%、66.0%、100%、29.4%和89.5%。控制穗发芽基因TaPHS1、TaMFT-A1和TaVp1B1各开发2个KASP标记,检测抗穗发芽基因占比分别是54.9%和53.6%、64.7%和89.5%、56.2%和2.6%,控制穗发芽基因TaSdr-B1位点优异等位变异占比25.5%。两个与抗旱相关的基因TaDREB-B1和Ta1-feh w3优异等位变异占比分别是49.0%和39.9%。抗叶锈病基因Lr14a和Lr68优异等位变异占比分别是41.8%和26.8%;Lr34基因开发了2个KASP标记,仅一个标记检测Lr34抗性基因,占比0.7%;Lr15抗条锈病基因占比2.0%;Fhb抗赤霉病基因占比3.9%;抗小麦黄斑叶枯病基因Tsn1占比63.4%。综上所述,KASP标记高效检测小麦重要农艺性状的优异等位变异,在河北省小麦重要农艺性状改良方面将有良好的应用前景。     

春化、光周期和矮秆基因在不同国家小麦品种中的分布及其效应

为促进国外种质资源在我国的有效利用,将14个国家的100份代表性小麦品种在国内的8个代表性地点种植,调查抽穗期、成熟期和株高,并以4个春化基因(Vrn-A1、Vrn-B1、Vrn-D1和Vrn-B3)、1个光周期基因(Ppd-D1a)及2个矮秆基因(Rht-B1b和Rht-D1b)的分子标记检测所有品种的基因型。春化基因Vrn-A1a、Vrn-B1、Vrn-D1和vrn-A1+vrn-B1+ vrn-D1的分布频率分别为8.0%、21.0%、21.0%和64.0%;显性等位变异Vrn-A1a、Vrn-B1和Vrn-D1主要存在于来自中国春麦区及意大利、印度、加拿大、墨西哥和澳大利亚的品种中,这些品种一般为春性类型;春化位点均为隐性等位变异或vrn-A1+vrn-D1+Vrn-B1的品种主要分布在中国冬麦区、美国冬麦区、俄罗斯冬麦区,以及英国、法国、德国、罗马尼亚、土耳其和匈牙利,这些地区的小麦均为冬性类型。秋播时,供试品种均能正常抽穗,且携带春化显性变异的材料较隐性类型抽穗早,显性等位变异表现加性效应,4个春化位点均为隐性变异的一些欧美材料因抽穗太晚在杨凌和成都不能正常成熟;而春播时,显性等位变异基因型抽穗的频率高,隐性等位变异基因型基本不能抽穗。光周期不敏感基因Ppd-D1a的分布频率为68.0%,主要分布在中国、法国、罗马尼亚、俄罗斯、墨西哥、澳大利亚和印度,而光周期敏感等位变异Ppd-D1b主要分布在英国、德国、匈牙利和加拿大等中高纬度地区;携带Ppd-D1a的品种较携带Ppd-D1b的品种抽穗早,大多数Ppd-D1a品种在长日照和短日照条件下均能成熟,大部分Ppd-D1b品种在短日照条件下不能成熟。Rht-B1b和Rht-D1b基因的分布频率分别为43.0%和35.0%,其中Rht-B1b主要分布于美国、罗马尼亚、土耳其、意大利、墨西哥和澳大利亚,Rht-D1b主要分布于中国、德国、英国、意大利和印度。一般来说,一个国家的品种携带Rht-B1b或Rht-D1b之一,而这2个基因在高纬度地区分布频率较低。Rht-B1b、Rht-D1b和Ppd-D1a的降秆作用均达显著水平,Rht-B1b和Rht-D1b的加性效应突出。     

河北省旱碱麦品质和抗性相关基因的KASP标记检测

利用12个小麦品质、抗病和抗逆等相关的KASP标记,对河北省育成的部分旱碱麦和农家种(54份)进行KASP标记检测.结果表明,在品质方面,有15份材料含有Glu-D1基因的高分子量麦谷蛋白亚基5+10,有32份材料是Glu-A1基因的Ax1 orAx2*强筋单倍型.在抗病性方面,有25份含有抗叶锈病基因Lr34,有27...     

西南地区87份小麦品种(系)穗发芽抗性的分子鉴定及筛选

小麦穗发芽使小麦的产量大幅度降低,严重影响小麦的加工品质,而西南麦区一直是小麦穗发芽的重发区。为了在历史小麦品种(系)中鉴定出抗穗发芽的种质材料,本研究以来自西南麦区的87份小麦主推品种及后备品系为研究材料,利用PM19、Vp1B3两种抗穗发芽候选基因进行分子标记,为抗穗发芽育种提供种质资源。结果表明,在87份小麦中有4份含有PM-19A1a基因,分别是科成4号、兴0217、蜀麦1763、SW 1747;有9份含有Vp-1Bb基因,分别是黔麦0504、16092、绵麦303、内麦366、川麦604、BL 5002、BL 6007、2017 P 4-2、SW 1747。     

小麦小穗数调控基因WAPO1的单倍型、遗传效应、地理分布及育种利用分析

小麦穗部性状直接与产量相关,是极重要的农艺性状。WAPO1编码F-box蛋白,是水稻小穗数发育相关基因APO1在小麦中的直系同源基因。本研究鉴定了WAPO1的优异单倍型,并对其遗传效应、地理分布和育种利用情况进行了鉴定。通过开发的KASP标记对编码区第140位碱基变异SNP(G/T)进行鉴定,并使用前人报道的启动子InDel标记对WAPO1启动子115bp的插入缺失进行鉴定,在中国地方小麦中进行单倍型鉴定。结果显示,在前人鉴定到的3种单倍型(H1: 140~G+115^deletion, H2:140~T+115^insertion, H3: 140~G+115^insertion)基础上,鉴定到了新的第4种单倍型(H4:140~T+115^deletion)并证明H2和H4为优异单倍型,能显著提高小麦每穗小穗数。将开发的KASP标记对223份世界小麦、144份中国育成小麦和119份四川小麦进行分型,筛选出优异单倍型并对其在育种中的利用和分布进行了鉴定,结果表明优异单倍型在中国和世界范围都被广泛选育。     

红粒小麦Tamyb10单倍型检测及其与穗发芽抗性的关系

穗发芽是影响小麦品质和产量的重要因素之一,通常红粒小麦比白粒小麦具有较高的穗发芽抗性。转录因子Tamyb10是R-1基因的强候选基因,其表达与否和表达水平决定小麦籽粒颜色。为阐明Tamyb10单倍型与红粒小麦穗发芽抗性的关系,利用已开发的Tamyb10基因分子标记,检测119份来自不同麦区的红粒小麦材料,发现Tamyb10基因(Tamyb10-A1、Tamyb10-B1和Tamyb10-D1位点)可分成7类单倍型,分别是baa、aba、bba、aab、bab、abb和bbb。Tamyb10-D1对穗发芽抗性影响最大,Tamyb10-B1次之,Tamyb10-A1作用最小。Tamyb10单倍型没有明显的地域分布特点,但在东北春麦区,Tamyb10单倍型bbb与红粒品种的高穗发芽抗性相关。     

分子标记Tamyb10D和TaDFR-B的有效性验证及对小麦抗穗发芽基因型的筛选

为了比较与小麦穗发芽抗性相关分子标记的有效性以及在白粒小麦品种中筛选出抗穗发芽的基因型材料,选择已报道的2个与穗发芽抗性相关的标记Tamyb10D和Ta DFR-B,对2套白粒小麦试材(78,103份)的穗发芽抗性进行综合筛选。结果表明:标记Tamyb10D可有效地用于白粒小麦穗发芽抗性筛选,而标记Ta DFR-B不适用于白粒小麦品种(系)材料的穗发芽抗性筛选的鉴定。通过分子标记Tamyb10D的筛选结果和发芽指数的评价,结合以前用分子标记Vp1B3的检测结果,在103份试材中筛选出5份具有高抗穗发芽基因型材料(GI10%),分别是:阆中白麦子、万县白麦子、陪陵须须白麦、川362和小白玉花,其单倍型分别是:Tamyb10D/Vp-1Bb、Tamyb10D/Vp-1Bb、Tamyb10D/Vp-1Bb、Tamyb10D/Vp-1Bb、Tamyb10D/Vp-1Bc;在另外一套(78份)试材中筛选出10份具高抗有穗发芽基因型材料(GI10%),分别为西农6028、克群、百农3217、开封124、郑州742、西昌5762、小偃5号、克壮、许跃6号和武农99,其单倍型均为Tamyb10D/Vp-1Bc。     

基于小麦外引种质资源的抗旱性分子标记检测及实用性评价

为了有效利用外引小麦种质资源和评价小麦抗旱性相关分子标记的有效性,以48份小麦外引种质为材料,测定干旱条件下种子的相对发芽率,并利用4个小麦抗旱性相关分子标记进行抗旱基因(1-feh-w3、Dreb-B1、NRX-B1和FerA1)的分布检测。结果表明,外引种质材料的平均相对发芽率为70.0%,变异范围为34.9%～94.5%,中等及以上抗旱性等级种质材料占85.4%。外引小麦种质中4个抗旱性相关基因存在8种单倍型,Dreb-B1、FerA1基因各自的2种单倍型间平均相对发芽率差异均达到显著水平,而1-feh-w3基因的Westonia type单倍型与Kauz type单倍型,NRX-B1基因的TaNRX-B1a单倍型与TaNRX-B1b单倍型间平均相对发芽率无显著差异;TaDreb-B1a、TaFer-A1(H)单倍型与平均相对发芽率均呈显著正相关,1-feh-w3、NRX-B1基因与平均相对发芽率相关性不显著。平均相对发芽率以单倍型组合Westonia type/TaDreb-B1a/TaFer-A1(H)/TaNRX-B1a最高,达到77.35%。验证了抗旱性基因Dreb-B1分子标记的有效性,而1-feh-w3基因2种单倍型对抗旱性选择无效。     

山东小麦品种中矮秆基因Rht-B1b、Rht-D1b分布的分子鉴定

利用小麦矮秆基因Rht—B1b、Rht—D1b的4对特异分子标记,NH—BF和MR1、NH—BF和WR1．2、DF和MR2、DF和WR2,对山东小麦品种中矮秆基因Rht—B1b及Rht—D1b的分布情况进行了分子标记鉴定,结果表明在鉴定的150个品种中有20．67％含有Rht—B1b基因,有54．00％含有Rht—D1b基因,二者合计为74．67％;同时含有Rht—B1b和Rht—D1b2个矮秆基因的仅占3．33％。表明山东小麦矮化育种中Rht—D1b基因的利用远高于Rht—B1b。     

Distribution of the Rht-B1b, Rht-D1b and Rht8 reduced height genes in autumn-sown Chinese wheats detected by molecular markers

Reduction of plant height has played a significant role in improving wheat production and knowledge of dwarfing genes in Chinese wheat will be very important for developing high yielding cultivars. Molecular markers were used to detect the presence of genes Rht-B1b (Rht1), Rht-D1b (Rht2) and Rht8 in 220 wheat genotypes from autumn-sown wheat regions in China. They include landmark landraces, leading cultivars and core parents involved in wheat breeding from the 1950s to the present. Results indicated that Rht-D1b and Rht8 dominate with frequencies of 45.5% and 46.8%, respectively, followed by Rht-B1b with a frequency of 24.5%. The frequencies of Rht-B1b and Rht-D1b increased, from 8.6 to 32.2% and 36.2 to 53.4%, respectively, whereas the frequency of Rht8 has remained constant over time, when compared with cultivars released before and after 1990. This indicates that both the Rht-B1b and Rht-D1b were successfully used in wheat production in Chinese environments. Our study shows that Rht-B1b and Rht-D1b can be used in the post-anthesis heat stressed environments. Rht-B1b in Chinese wheats is derived from two sources, viz., Norin 10 and the Italian introduction St2422/464 (Rht-B1b and Rht8). The identity of Rht-B1b in these two sources still needs to be confirmed. Suwon 86 carrying both Rht-B1b and Rht-D1b, and Chinese cultivars, Huixianhong and Yaobaomai, are the primary sources of Rht-D1b in Chinese wheats. It is likely that Rht-D1b in Youbaomai derives from an unknown introduction. Italian introductions such as Funo and Abbondanza, and Lovrin 10 with the 1B/1R translocation, and Chinese landraces are the three major sources of Rht8. This information will be very valuable for wheat breeding in China, and internationally.     

Confirmation of the relationship between plant height and Fusarium head blight resistance in wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.) by QTL meta-analysis

Fusarium head blight (FHB) is a serious wheat disease all over the world. In this study, the relationships between plant height (PH) and FHB were investigated across the whole wheat genome by QTL meta-analysis from fifty-six experiments. Coincident meta-QTL (MQTL) for PH and FHB were found on chromosomes 2D, 3A, 4B, 4D and 7A. Rht-B1, Rht-D1, Rht8, MQTLs P7 and P26 were consistent with FHB MQTLs. The meta-analysis results confirmed the negative associations of Rht-B1, Rht-D1, and Rht8 with FHB resistance. The associations of PH and FHB resistance on chromosomes 3A and 7A have not been reported and need further investigation. These regions should be given attention in breeding programs. MQTLs derived from several resistance sources were also observed. Some FHB MQTLs for different types of resistance overlapped. These findings could be useful for improving wheat varieties with resistance to FHB.     

Effect of the Rht-D1 dwarfing locus on Fusarium head blight rating in three segregating populations of winter wheat

Fusarium head blight (FHB) is one of the major fungal diseases in wheat throughout the world. To control FHB severity, breeding genetically resistant varieties is thought to be the most promising strategy. In wheat breeding programmes, short cultivars predominantly carrying the Norin 10 derived semi-dwarfing allele Rht-D1b ( Rht2 ) are preferred worldwide because of higher achievable grain yields and lower risk of lodging. This study was conducted to determine the influence of different alleles at the Rht-D1 locus on FHB reaction. Three winter wheat populations were produced by crossing rather susceptible varieties 'Biscay', 'Pirat' and 'Rubens' carrying mutant-type allele Rht-D1b with the more resistant varieties 'Apache', 'Romanus' and 'History' containing the Rht-D1a wild-type allele ( rht2 ). The 190, 216 and 103 progeny of the F₄-derived populations were assayed for the presence of Rht-D1a or Rht-D1b , plant height, and mean FHB rating after spray inoculation at flowering time with a highly aggressive isolate of Fusarium culmorum . Comparably, high mean FHB severities ranging from 28% to 49% for all population × environment combinations were achieved, with significant genotypic variation for FHB rating and plant height within all populations. Both traits were negatively correlated with r ranging from −0.48 to −0.61 in the complete populations. However, within the subpopulations homozygous for one or other height allele these correlations decreased considerably. The Rht-D1b semi-dwarfing allele resulted in 7–18% shorter plants, depending on the population, but a considerably increased FHB reaction of 22–53%. Nevertheless, significant genotypic variance for FHB resistance remained in all tested Rht-D1b subpopulations indicating that selection for moderately FHB resistant genotypes within agronomically beneficial Rht-D1b genotypes is still feasible.     

可用于小麦品质改良的农家种种质筛选

为了筛选综合性状较好的可用于小麦品质改良的农家种资源,以212份小麦农家种为材料,采用Vp1B3分子标记和田间喷雾进行了抗穗发芽鉴定,用硬度指数法进行了硬度测定,并考察了部分农艺性状。结果表明,212个农家种中Vp-1Ba（感穗发芽）、Vp-1Bb（抗穗发芽）和Vp-1Bc（抗穗发芽）基因型的频率分别为70.28%,6.16%,23.70%,以Vp-1Ba基因型为主。3种基因型穗发芽率差异不显著,212个农家种的穗发芽率在7.79%~28.56%之间,平均为15.28%;农家种硬度指数(HI)平均值为71.22;农家种平均株高达到113.46 cm;农家种对白粉病抗性变异丰富,有3个品种为白粉病免疫;农家种平均穗粒数为28.33,平均千粒重为30.96 g。针对抗穗发芽、籽粒硬质、株高适宜、抗白粉病、高产等育种目标,筛选出等‘金包银’、‘玉麦1’、‘大红芒2’等12个种质材料,为进一步培育优质小麦奠定了基础。     

Phosphorus use efficiency in tall, semi-dwarf and dwarf near-isogenic lines of spring wheat

The impact of the Rht dwarfing genes on P utilization efficiency (PUTE = grain dry matter per kg P in above-ground biomass), total P uptake (Pt) and related traits was studied in the varietal backgrounds of two tall wheat cultivars, Maringa and Nainari 60. Four sets of near-isogenic lines carrying different combinations of the alleles Rht-B1b, Rht-D1b and Rht-B1c for gibberellin-insensitive dwarfism in the hexaploid wheat (Triticum aestivum L.) were compared with tall controls in two field trials under conditions of adequate nutrient supply and irrigation in Northwest Mexico. The yield-increasing effect of the dwarfing genes Rht-D1b and Rht-B1b led to improved PUTE in Maringa and total P uptake in both cultivars. Also, the double dwarf line of Maringa had larger grain yields and P uptake compared to the tall control. The Rht-B1c genotypes showed low PUTE, thick roots and high P concentration in vegetative biomass indicating a surplus of assimilates and P, which could not be translocated into the grains. A similar problem could be observed in Nainari 60 with Rht-B1b and Rht-D1b, which produced the largest grain dry matter with the lowest P concentrations in grains although they showed high P accumulation in straw. Most of the net P uptake occurred before anthesis. P absorption after anthesis was more critical for the dwarf genotypes. For double dwarfs and Rht-B1c, respectively, only 3% and 21% of the total accumulated P at maturity was absorbed at post-anthesis. The grain P of the dwarf lines came more from P accumulated at pre-anthesis and translocated from the vegetative biomass into the grain. The pre-anthesis P accumulation was positively correlated with spikes per m² (r = 0.91), whereas post-anthesis P accumulation correlated better with grains per spike(r = 0.72), and thousand kernel weight (r = 0.51). P uptake efficiency played a secondary role under these non-P-limiting conditions, and differences in root length density were only slightly affected by Rht-genes. This revised version was published online in July 2006 with corrections to the Cover Date.     

A 192bp allele at the <Emphasis Type="Italic">Xgwm261</Emphasis> locus is not always associated with the <Emphasis Type="Italic">Rht8</Emphasis> dwarfing gene in wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.)

The height-reducing gene Rht8 was introduced into Italian wheats by breeder Nazareno Strampelli from the Japanese landrace Akakomugi, and has been widely used in wheats adapted to southern and eastern European conditions. Following identification of a close linkage to Rht8, microsatellite marker Gwm261 has been used extensively to screen large numbers of diverse international germplasm. A 192bp allele at this locus has been taken as “diagnostic” for Rht8 and used to infer the international distribution of Rht8. In this paper, we report several instances of cultivars and mapping populations that vary for the presence of the 192bp allele at the Xgwm261 locus (Xgwm261 ₁₉₂ ), but with no associated reduction in height, suggesting a lack of association with Rht8. For instance, in the population derived from a cross between Sunco (Rht-B1b, Xgwm261 ₁₆₅ ) and Tasman (Rht-D1b, Xgwm261 ₁₉₂ ), there were significant height differences associated with the segregation of Rht-B1b and Rht-D1b, but no height differences between Xgwm261 genotypes. Similar results were obtained in a population derived from the cross between Molineux (Rht-B1b, Xgwm261 ₁₉₂ ) and Trident (Rht-D1b Xgwm261 ₂₀₈ ). In contrast, the cross between Trident and Chuanmai 18 (Xgwm261 ₁₉₂ ) gave significant height effects at both the Rht-D1 and Xgwm261 loci, with no epistatic interaction between loci. Chuanmai 18 is closely related to the Strampelli wheat Mara (ancestrally derived from Akakomugi) and is therefore likely to carry Rht8. The old Japanese cultivar Norin 10, used by Norman Borlaug to introduce Rht-B1b and Rht-D1b into Mexican wheats, also has a 192bp allele at the Xgwm261 locus, and the sequence of the amplified product is identical to that of Akakomugi. We suggest that the widespread use of Norin 10-derived germplasm during and after the Green Revolution introduced a second haplotype into international germplasm, in which Xgwm261 ₁₉₂ has no association with Rht8. Therefore, the presence of Xgwm261 ₁₉₂ is only indicative of Rht8 in wheat cultivars that have inherited this allele from Akakomugi or a Strampelli wheat ancestor.