春化和光周期基因等位变异在23个国家小麦品种中的分布

为促进国外资源在我国小麦育种中的有效利用,以小麦春化基因Vrn-A1、Vrn-B1、Vrn-D1和Vrn-B3及光周期位点Ppd-D1标记对23个国家的755份品种检测,同时在河南安阳秋播,观察抽穗期和成熟期。分子标记检测结果表明,Vrn-A1、Vrn-B1、Vrn-D1和vrn-A1+vrn-B1+ vrn-D1的分布频率分别为13.0%、21.1%、15.6%和64.2%,显性等位变异Vrn-B3在检测材料中缺失。春化基因显性等位变异Vrn-A1、Vrn-B1和Vrn-D1主要分布在中国春麦区和长江中上游冬麦区、意大利、印度、日本、加拿大、墨西哥、智利、阿根廷和澳大利亚,上述地区的小麦一般为春性类型;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北方、美国中部和南部、德国、法国、挪威、乌克兰、俄罗斯、伊朗、土耳其、匈牙利、保加利亚、罗马尼亚和塞尔维亚,这些地区的小麦为冬性类型。光周期迟钝型Ppd-D1a的分布频率为55.2%。光周期敏感等位变异Ppd-D1b主要分布在纬度较高的地区,即美国各麦区以及德国、挪威、匈牙利、中国东北、加拿大、智利和阿根廷,来自其余麦区的品种均携带光周期迟钝等位变异Ppd-D1a;携带Ppd-D1a的品种在河南安阳大部分能够成熟,而携带Ppd-D1b的品种在河南安阳基本不能成熟。在安阳春化显性等位变异Vrn-A1a未加速小麦抽穗,而携带Vrn-B1和Vrn-D1等位变异的部分春化需求品种能够正常抽穗,主要因安阳生长季节的温度能够满足春化需求。     

STS标记鉴定河南历史主推小麦品种春化光周期基因及与品种冬春性的相关性

为了解河南小麦栽培历史上主推小麦品种春化及光周期基因种类及分布特点,采用STS分子标记鉴定了河南小麦栽培历史上主推的43个品种的4种春化基因Vrn-A1、Vrn-B1、Vrn-D1、Vrn-B3和1个光周期基因Ppd-D1位点的显隐性。结果表明:Vrn-A1、Vrn-B3基因位点均为隐性,Vrn-B1和Vrn-D1显性基因频率分别为7.0%、51.1%,光周期显性基因Ppd-D1a频率为93.0%,研究结果说明河南历史上主推的小麦品种中,隐性春化基因和光周期不敏感的显性基因占主导。鉴定结果还表明,43份品种的春化基因与光周期基因组合有4类,第一类为vrn-A1+Vrn-B1+vrn-D1+vrn-B3+Ppd-D1a;第二类为vrn-A1+vrn-B1+Vrn-D1+vrn-B3+Ppd-D1a;第三类为vrn-A1+vrn-B1+vrn-B3+Vrn-D1+Ppd-D1b;第四类为vrn-A1+vrn-B1+vrn-B3+vrn-D1+Ppd-D1a,其所占频率依次为:7.0%、44.2%、7.0%、41.9%。春性品种至少携带一个显性春化基因Vrn-B1或Vrn-D1,且其光周期基因一定是光周期不敏感基因Ppd-D1a;冬性品种的4个春化基因位点均为隐性或仅含显性春化基因Vrn-D1,光周期敏感的隐性基因Ppd-D1b只在冬性品种中检出。通过鉴定小麦春化基因及光周期基因,我们明确了河南小麦栽培历史上主推品种的春化和光周期基因的种类、组成特点及品种演变趋势,对改良小麦品种适应性具有重要参考价值。     

等位变异Vrn-B1a和Vrn-B1b的春化效应及其在黄淮冬麦区小麦品种中的分布

春化基因Vrn-B1是决定黄淮冬麦区小麦品种冬春性的主要基因之一, 研究其不同显性等位变异的低温春化作用效应及分布, 对该区小麦品种选育和推广具有重要意义。以等位变异Vrn-B1a品种皖麦33与等位变异Vrn-B1b品种豫麦34为亲本构建杂交组合, 对其F₂代进行5~35 d的低温春化处理, 并在温室(22±3℃,16 h昼/8 h夜)鉴定抽穗期, 结合分子标记分析低温春化处理时间对各等位变异型抽穗期的影响。同时对228个黄淮冬麦区小麦品种进行相关位点分子检测, 分析该基因等位变异的分布特点。各春化处理均使两种等位变异小麦植株的抽穗期提前, 但Vrn-B1a抽穗时间比Vrn-B1b晚约2 d。从春化处理当天至处理后25 d, 2种等位变异类型的抽穗时间均随春化时间的延长而缩短; 继续延长春化时间, 抽穗期不再缩短, 表明满足两种等位变异完成春化的低温时间为20~25 d。在228个品种中, Vrn-B1位点有214个(93.9%)隐性和14个(6.1%)显性等位变异。其中, 显性等位变异Vrn-B1a有6个, 占总品种数的2.6%; Vrn-B1b有8个, 占总品种数的3.5%。在黄淮冬麦区小麦品种中, 春化基因Vrn-B1位点至少存在Vrn-B1a和Vrn-B1b两种显性等位变异类型, 两种等位变异类型纯合小麦植株的抽穗时间不同。     

小麦新品种春化和光周期基因组成以及春化基因与产量性状的关系

为研究春化和光周期基因在河南省小麦新品种中的分布特点及春化基因与产量性状的关系,以近年河南省冬小麦品种区域试验的118份小麦品种为材料,用STS标记对4个春化基因位点(Vrn-A1,Vrn-B1,Vrn-D1和Vrn-B3)和1个光周期基因位点(Phd-D1)进行检测,并结合供试材料的农艺性状,分析近年来河南省小麦新品种春化基因组成及其与品种的冬春性、苗穗期及产量性状的相关性。结果表明,供试的118份小麦品种在Phd-D1、Vrn-A1、Vrn-B3位点均为隐性等位变异;含有显性等位变异Vrn-B1的品种有9份,其分布频率为7.62%,且均表现为弱春性;含有显性等位变异Vrn-D1的品种有41份,其分布频率为34.7%,这些品种中有21份表现为弱春性;进一步的分析表明,显性等位变异Vrn-D1与苗穗期显著负相关,与产量构成各要素正相关,但未达显著水平;显性等位变异Vrn-B1与产量构成要素中的成穗数和穗粒数负相关,而与千粒重正相关,但均未达显著水平。     

中国主要小麦品种春化基因的STS标记鉴定

本文选取来自中国各麦区的260份小麦品种,用STS标记对其Vrn-A1、Vrn-B1、Vrn-D1和Vrn-B3四个春化基因位点进行检测,并结合小麦田间生长情况记录,探讨春化基因的4个位点显隐性情况对品种冬春性的影响.结果表明,各位点显性基因频率以Vrn-D1位点最高,而Vrn-A1和Vrn-B1显性等位基因对品种冬春性的影响高于Vrn-D1和Vrn-B3基因,且所含显性春化基因越多的品种生长习性越偏向春性.另发现,Vrn-A1仅存在于春性品种中;而对于冬性品种来说,各位点均不含显性春化基因.本文标记鉴定结果与田间冬春性观察具有较高的一致性,在小麦育种及品种推广中具有较高的指导意义和应用价值.     

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。     

光周期基因在我国小麦品种中的多态性分布

为了明确光周期基因显隐性组成在我国小麦品种中的分布情况,利用小麦光周期基因Ppd-A1、Ppd-B1和Ppd-D1的STS分子标记,对我国180份小麦品种进行分子标记检测。结果显示,所有供试材料在B1位点均检测为隐性Ppd-B1b。在A1位点,仅有扬麦11品种检测为显性Ppd-A1a(0.6%),其余检测材料均为隐性Ppd-A1b;在D1位点,有5份材料检测为隐性,其余175份材料检测均为显性Ppd-D1a(97.2%)。对所有材料进行基因型统计分析,发现我国品种主要存在Ppd-A1b/Ppd-B1b/Ppd-D1b、Ppd-A1b/Ppd-B1b/Ppd-D1a和Ppd-A1a/Ppd-B1b/Ppd-D1a几种基因型。研究结果表明,我国小麦品种的光周期不敏感特性主要是Ppd-D1位点的变异,在Ppd-A1、Ppd-B1位点的变异较少。     

小麦春化基因的遗传效应研究

为了解小麦春化基因Vrn-1的遗传效应,以15个不同类型的小麦品种为试材,研究了不同春化处理对小麦发育进程的影响,并采用分子标记鉴定了上述品种的Vrn-1等位基因组成.结果表明,不同Vrn-1等位基因组合的小麦品种抽穗期存在很大差异；3个显性Vrn-1等位基因的遗传效应表现为Vrn-A1＞Vrn-D1＞Vrn-B1；春...     

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。     

小麦叠氮化钠诱变群体重要功能基因的KASP标记检测

为了解沧麦6005叠氮化钠诱变群体中小麦重要功能基因的组成情况,利用高通量的KASP标记技术对小麦株高、抗病性、抗旱性、抗穗发芽、春化和品质等性状相关的基因进行了检测分析。结果表明:1)控制小麦株高的基因Rht-B1和Rht-D1在73份叠氮化钠诱变材料中出现6种组成类型,分别是Rht-B1a+197bp+Rht-D1a(1份)、Rht-B1a+197bp+Rht-D1b(39份)、Rht-B1a+Rht-D1a(1份)、Rht-B1a+Rht-D1b(13份)、Rht-B1b+Rht-D1a(13份)和Rht-B1b+Rht-D1b(3份),含有Rht-D1b的家系占全部突变家系的75.34%。2)在小麦抗病和抗逆性方面,73份诱变材料中发现含抗叶锈病基因Lr68的材料7份,含抗赤霉病基因Fhb1的材料5份,抗叶锈病基因Lr34在供试材料中未发现;在抗穗发芽方面,有3份材料含TaSdr-B1基因的TaSdr-B1a抗穗发芽单倍型,有53份材料含有PHS1基因的Rio Blanco type抗穗发芽单倍型,有16份材料含有TaMoc-A1基因的Hap-H抗穗发芽单倍型,在所有供试材料中含TaMFT-A1基因的Jagger-type和Zen/2174-type抗穗发芽单倍型的材料数分别为15份和22份;在抗旱性方面,有55份材料含有COMT-3B基因的3Ba单倍型,有28份材料含有Dreb-B1基因的TaDREB-B1a抗旱单倍型,有52份材料含有TaSST-4A基因的A2a抗旱单倍型;3)在小麦春化和早熟性方面均为一种单倍型,在春化方面,所有的诱变材料均为冬性类型。在早熟性方面,所有的供试材料在TaELF3-B1基因上均检测为晚开花的单倍型。4)在小麦品质方面,有45份材料含有高分子量麦谷蛋白亚基5+10,有18份材料含有Glu-A1基因的Ax1 or Ax2*强筋单倍型。综合表明,叠氮化钠诱变方法和KASP标记技术结合起来,可以作为一种小麦分子辅助育种的有效策略,能显著地提高小麦育种效率。     

Effect of alien 5R(5A) chromosome substitution on ear-emergence time and winter hardiness in wheat-rye substitution lines

Ear emergence time and response to vernalization were investigated in 12 alien substitution lines in which a pair of chromosomes 5A of recipient spring wheat cultivars was replaced by a pair of chromosomes 5R of Siberian spring rye ‘Onokhoiskaya’. The recipients were 12 spring cultivars of common wheat, each carrying different Vrn genes. Spring rye ‘Onokhoiskaya’ had the Sp1 (now called Vrn-R1) gene for spring growth habit located on chromosome 5R, but its expression was weaker. The Vrn-R1 gene had no effect on growth habit, ear emergence time and response to vernalization in wheat-rye substitution lines. Ears emerged significantly later in the 5R(5A) alien substitution lines than in the recipient wheat cultivars with the Vrn-A1/Vrn-B1/vrn-D1 or Vrn-A1/vrn-B1/Vrn-D1 genotypes. No difference in ear emergence time was found between most of the 5R(5A) alien substitution lines and the cultivars carrying the recessive vrn-A1 gene. The presence of the Vrn2a and Vrn2b alleles at the Vrn2 (now called Vrn-B1) locus located on wheat chromosome 5B was confirmed.The replacement of chromosome 5A by chromosome 5R in wheat cultivars ‘Rang’ and ‘Mironovskaya Krupnozernaya’, which carries the single dominant gene Vrn-A1, converted them to winter growth habit. In field studies near Novosibirsk the winter hardiness of 5R(5A) wheat–rye substitution lines of ‘Rang’ and ‘Mironovskaya Krupnozernaya’ was increased by 20–47% and 27–34%, respectively, over the recurrent parents.     

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.     

Distribution of photoperiod-insensitive alleles Ppd-B1a and Ppd-D1a and their effect on heading time in Japanese wheat cultivars

The genotypes of photoperiod response genes Ppd-B1 and Ppd-D1 in Japanese wheat cultivars were determined by a PCR-based method, and heading times were compared among genotypes. Most of the Japanese wheat cultivars, except those from the Hokkaido region, carried the photoperiod-insensitive allele Ppd-D1a, and heading was accelerated 10.3 days compared with the Ppd-D1b genotype. Early cultivars with Ppd-D1a may have been selected to avoid damage from preharvest rain. In the Hokkaido region, Ppd-D1a frequency was lower and heading date was late regardless of Ppd-D1 genotype, suggesting another genetic mechanism for late heading in Hokkaido cultivars. In this study, only 11 cultivars proved to carry Ppd-B1a, and all of them carried another photoperiod-insensitive allele, Ppd-D1a. The Ppd-B1a/Ppd-D1a genotype headed 6.7 days earlier than the Ppd-B1b/Ppd-D1a genotype, indicating a significant effect of Ppd-B1a in the genetic background with Ppd-D1a. Early-maturity breeding in Japan is believed to be accelerated by the introduction of the Ppd-B1a allele into medium-heading cultivars carrying Ppd-D1a. Pedigree analysis showed that Ppd-B1a in three extra-early commercial cultivars was inherited from ‘Shiroboro 21’ by early-heading Chugoku lines bred at the Chugoku Agriculture Experimental Station.     

中国黄淮海地区小麦品种抗寒性及其与VRN1基因型的关系

冬季冻害是当前小麦生产面临的主要自然灾害之一。以我国黄淮海地区近年主栽的71个小麦品种为材料,通过对其抗寒性调查和VRN-A1、VRN-B1、VRN-D1位点基因型的分子标记鉴定,研究小麦抗寒性的生物学基础,探讨VRN1基因在小麦抗寒性中的作用。结果表明,小麦的抗寒性与其他抗逆性状相关联,生产和国家区域试验证实具有较好抗旱节水、耐盐碱等抗逆特性的品种多具有较强抗寒性。VRN1是小麦抗寒性的关键性遗传调控位点之一,显性基因VRN1的存在会显著降低品种的抗寒性,具有2个或3个VRN1基因的品种一般抗寒性都很弱,而3个位点均为隐性基因是品种具有强抗寒性的必备条件。因此,建议我国黄淮海北部地区应加强选育、推广基因型为vrn-A1vrnB1vrn-D1的品种,以保证小麦安全生产。     

Molecular examination and genotype diversity of vernalization sensitivity and photoperiod response in old and modern bread wheat cultivars grown in Iran

Understanding the genetic factors governing developmental patterns and flowering time in breeding materials is required for the development of new wheat varieties for a specific environment. Iran is among the largest wheat producers in the arid and semi-arid regions of the Middle East and North Africa. The wheat germplasm grown in Iran is either developed nationally or is introduced from the CIMMYT global wheat program. For decades, the wheat breeding program in Iran focused on generating new varieties better able to grow in the predominant Iranian climatic conditions such as humidity at the reproductive stage, high temperature during reproductive stages (terminal heat stress), moderate temperature during the cropping season, and high probability of frost damage during early stages of growth. There have also been sub-programs aimed at developing drought and salinity-tolerant wheat cultivars in Iran. Knowledge of cultivars’ growth habits in Iran is currently limited to flowering in spring-sown nurseries. We identified allelic diversity in loci involved in vernalization response (Vrn) and photoperiod sensitivity (Ppd) in 60 bread wheat cultivars developed in Iran, CIMMYT, or ICARDA. This study revealed that the spring growth habit observed in most of the cultivars is conferred by a combination of recessive vrn-A1 and dominant Vrn-D1, Vrn-B1, and/or Vrn-B3 loci. This implies that most of the cultivars have minimal vernalization requirements for overwintering. Perhaps cold winters, even in the southern regions of Iran, provide sufficient vernalization conditions for cultivars possessing the recessive vrn-A1 allele. The germplasm investigated in this study revealed no evidence indicating selection for or against any specific Vrn and Ppd allele in our wheat breeding program.