Distribution of Grain Hardness in Chinese Wheats and Genetic Analysis

A hundred winter wheat and 41 spring wheat cultivars and advanced lines were used to investigate the distribution of grain hardness in Chinese wheats and correlations between grain hardness and other kernel traits. P1, P2, F1 , F2 and F3 from three crosses, i. e. , Liken2/Yumai2, 85Zhong33/Wenmai6 and 85Zhong33/95Zhong459 were sown to study the genetics of grain hardness. Significant correlation was observed between hardness measured by Single Kernel Characteristic System 4100 (SKCS 4100) and Near Infrared (NIR) Spectroscopy, r ranging from 0.85 to 0.94. Chinese wheat is a mixed population in terms of hardness, ranging from very soft to very hard. For autumn-sown wheat, on average, grain hardness decreases from north to south and spring-sown wheat is dominant with hard type. Hardness is negatively associated with flour color, and its associations with flour yield and ash content differ in winter and spring wheats. Grain hardness is controlled by a major gene and several minor genes with additive effect mostly, but dominant effect is also observed, with heritability of 0.78.

Genetic Analysis of Major and Minor Gene(s) Resistant to Stripe Rust in Important Resource Wheat Line Jinghe891-1

Inheritance of line Jinghe891-l resistant to pathotype of Puccinia striiformis in two patterns of temperature (Normal: day 18℃ /night 10℃ , High: day 24℃ /night 15℃ )was studied in this paper. The results showed that there were at least two pairs of dominant major genes and one pair of recessive minor genes in Jinghe 891-1. The two pairs of major genes that conferred resistance to CY31 were allelic or linked closely with resistance gene in Jubilejna Ⅱ , Kangyin655 and T. spelta Album. They were novel resistance genes and were inherited in a repeated or independent mode. The minor genes, which could modify the major genes, were sensitive to temperature and conferred resistance to all pathotypes of Puccinia striiformis in China. It is recommended that this line can be used as an important resource stock.

Genetic analysis of fertility restoring genes for AL-type male sterility in wheat

In order to screen molecular markers linked to fertility restoring genes and further improve the breeding efficiency of restorer lines, in this study, wheat varieties 18A, 18B and 99AR144-1 were used as experimental materials to establish F2 fertility-segregating population. Plant quantitative trait ＂major gene ＋ polygene mixed mo- del＂ separation analysis method and simple sequence repeat （SSR） molecular markers were adopted for genetic analysis of four generations, including the parents （P~ and P2）, and hybrid （G and G） populations. The results show that AL-type fertility restoring gene is controlled by two pairs of additive-dominant-epistatic genes and addi- tive-dominant polygene; two primers linked to fertility restoring genes were selected by SSR molecular markers, including Xgwm95 on chromosome 2A and Barc61 on chromosome 1B, with the linkage distance of 15.0 cM and 18.0 cM, respectively. Based on verification, these two markers are reliable for distinguishing AL-type wheat ste- rile lines and restorer lines.

Identification of genetic locus with resistance to take-all in the wheat-Psathyrostachys huashanica Keng introgression line H148

Take-all is a devastating soil-borne disease of wheat(Triticum aestivum L.).Cultivating resistant line is an important measure to control this disease.Psathyrostachys huashanica Keng is a valuable germplasm resource with high resistance to take-all.This study reported on a wheat-/R huashanica introgression line H148 with improved take-all resistance compared with its susceptible parent 7182.To elucidate the genetic mechanism of resistance in H148,the F_(2)genetic segregating population of H148×XN585 was constructed.The mixed genetic model analysis showed that the take-all resistance was controlled by two major genes with additive,dominant and epistasis effects.Bulked segregant analysis combined with wheat axiom 660K genotyping array analysis showed the polymorphic SNPs with take-all resistance from P.huashanica alien introgression were mainly distributed on the chromosome 2A.Genotyping of the F_(2)population using the KASP marker mapped a major QTL in an interval of 68.8-70.1 Mb on 2AS.Sixty-two genes were found in the target interval of the Chinese Spring reference genome sequence.According to the functional annotation of genes,two protein genes that can improve the systematic resistance of plant roots were predicted as candidate genes.The development of wheat-P.huashanica introgression line H148 and the resistant QTL mapping information are expected to provide some valuable references for the fine mapping of disease-resistance gene and development of take-all resistant varieties through molecular marker-assisted selection.

Evaluation of Aegilops tauschii for Heading Date and Its Gene Location in a Re-synthesized Hexaploid Wheat

The successful worldwide cultivation of hexaploid wheat in a diverse range of environments is because of, in part, breeding and selection for appropriate heading date. To adjust and fine-tune the heading time of hexaploid wheat to particular geographical regions and specific environment within these, there is an urgent need to evaluate and use alternative alleles for heading time. Aegilops tauschii, the donor species of D-genome of hexaploid wheat, has a wide geographic distribution. The present study revealed a wide variation for heading time among 56 Ae. tauschii accessions. All the accessions with short heading dates belonged to the ssp. tauschii, whereas most of ssp. strangulata accessions showed very long heading date. The heading date was also related to distribution of this species. The monotelosomic and monosomic analysis of a synthetic hexaploid wheat showed that chromosome 2D derived from ssp. tauschii accession AS60 had a major effect on promoting heading time with a reduction of more than 5 days. It is postulated that this Ae. tauschii genotype possess the allele Ppd-D^t1 responsible for the insensitivity to photoperiod. This allele is probably different from Ppd-D1 existing in hexaploid wheat. The new allele Ppd-D^t1 derived from Ae. tauschii might be used as a source for hexaploid wheat breeding on photoperiod response.

Preliminary Study on Inheritance of Stigma Exertion in Wheat Thermo-photo Sensitive Genic Male Sterile Line

Stigma exertion is one of the key factors for improving the outcrossing ability of wheat thermo-photo sensitive genic male sterile（TPSGMS） line. A DH population derived from K239S/K92 S was constructed to investigate the inheritance of stigma exertion. K239 S and K92 S are TPSGMS lines with higher and lower stigma exertion rates（SER）, respectively. The SERs of parents, reciprocal crosses and the DH population were evaluated for two consecutive years. The results showed that no significant difference was observed in SER between F1 s of K239S/K92 S and K92S/K239 S,implying that stigma exertion was a trait controlled by nuclear gene（s）. In the DH population, the segregation of low and high SERs fitted to a ratio of 3 ∶1 by Chisquare test, suggesting that the stigma exertion of K239 S was controlled by one pair of recessive genes. In addition, the effects of temperature and humidity on the expression of stigma exertion were also discussed.

Genetic Analysis of Stripe Rust Resistance of Xikemai 6 at Adult Plant Stage

To confirm resistance and genetic rules of Xikemai 6 against physiological races of wheat stripe rust,physiological races CYR31,CYR32 and CYR33,Su11-4 and V26 were inoculated in Xikemai 6 and Mingxian 169 and their hybrid progenies F_1,F_2 and F_3 at adult plant stage on March 2015. The results showed that the resistance of Xikemai 6 against CYR31 was controlled by 2 pairs of dominant genes and a pair of recessive genes; the resistance against CYR32 was controlled by three pairs of dominant resistant genes（ two pairs of genes performed cumulative effect）; the resistance against CYR33 was controlled by a pair of dominant genes and a pair of recessive genes; the resistance against Su11-4 was controlled by a pair of dominant genes and a pair of recessive genes independently or collaboratively; the resistance against V26 was controlled by a pair of dominant genes independently. Due to good performance of Xikemai 6 in test and production,as well as years of resistance identification and genetic analysis,Xikemai 6 was proved to be an excellent cultivar with good resistance against stripe rust,and the inheritance of its resistance was stable,so Xikemai 6 could be used as a germplasm resource and resistance material with excellent comprehensive character. Molecular marker and localization could be further studied,to provide new resistance parents for disease-resistant breeding of wheat.

Advances in the Study of Protein Quality Traits and Main Influencing Factors of Wheat in China

Wheat, the third major grain crop in China, is an important source of hu- man proteins. Wheat quality and yield has a direct impact on the development of agricultural economy and food industry. Investigating and improving protein quality of wheat has become a key to solving the contradiction. This paper reviewed the exist- ing literature published at home and abroad, analyzed the present situation and ex- isting problems of wheat protein quality in China, summarized the latest research progress about genetic models, main influencing factors, and correlations between protein quality traits and other traits, discussed current issues in the improvement of wheat protein quality, and proposed suggestions for breeding high-quality wheat, aiming at providing theoretical basis for genetic improvement, planting structure ad- justment and efficient production of high-quality wheat.

Detection of scab in wheat ears using in situ hyperspectral data and support vector machine optimized by genetic algorithm

A new method was proposed to extract sensitive features and to construct a monitoring model for wheat scab based on in situ hyperspectral data of wheat ears to achieve effective prevention and control and provide theoretical support for its large-scale monitoring.Eight sensitive features were selected through correlation analysis and wavelet transform.These features were as follows:three original bands of 350-400 nm,500-600 nm,and 720-1000 nm;three vegetation indices of modified simple ratio(MSR),normalized difference vegetation index,and structural independent pigment index;and two wavelet features of WF01 and WF02.By combining the selected sensitive features with support vector machine(SVM)and SVM optimized by genetic algorithm(GASVM),a total of 16 monitoring models were built,and the monitoring accuracies of the two types of models were compared.The ability of the monitoring models built by GASVM to identify scab was better than that of SVM algorithm under the same characteristic variables.Among the 16 models,MSR combined with GASVM had an overall accuracy of 75%and a Kappa coefficient of 0.47.GASVM can be used to monitor wheat scab and its application can improve the accuracy of disease monitoring.

DIW1 encoding a cladeⅠPP2C phosphatase negatively regulates drought tolerance by de-phosphorylating TaSnRK1.1 in wheat

Drought seriously impacts wheat production(Triticum aestivum L.),while the exploitation and utilization of genes for drought tolerance are insufficient.Leaf wilting is a direct reflection of drought tolerance in plants.Clade A PP2Cs are abscisic acid(ABA)co-receptors playing vital roles in the ABA signaling pathway,regulating drought response.However,the roles of other clade PP2Cs in drought tolerance,especially in wheat,remain largely unknown.Here,we identified a gain-of-function drought-induced wilting 1(DIW1)gene from the wheat Aikang 58 mutant library by map-based cloning,which encodes a cladeⅠprotein phosphatase 2C(TaPP2C158)with enhanced protein phosphatase activity.Phenotypic analysis of overexpression and CRISPR/Cas9 mutant lines demonstrated that DIW1/TaPP2C158 is a negative regulator responsible for drought resistance.We found that TaPP2C158 directly interacts with TaSnRK1.1 and de-phosphorylates it,thus inactivating the TaSnRK1.1–Ta AREB3 pathway.TaPP2C158 protein phosphatase activity is negatively correlated with ABA signaling.Association analysis suggested that C-terminal variation of TaPP2C158 changing protein phosphatase activity is highly correlated with the canopy temperature,and seedling survival rate under drought stress.Our data suggest that the favorable allele with lower phosphatase activity of TaPP2C158 has been positively selected in Chinese breeding history.This work benefits us in understanding the molecular mechanism of wheat drought tolerance,and provides elite genetic resources and molecular markers for improving wheat drought tolerance.

新疆冬小麦籽粒品质性状遗传差异与关联分析

小麦籽粒品质与面粉加工的食品品质密切相关,是小麦早期品质选择的重要依据。本研究以产自新疆的134个冬小麦地方品种和54个育成品种为材料,对连续2年种植收获于新疆乌鲁木齐市、新疆伊宁市共计4个试验点的小麦籽粒进行品质检测与全基因组关联分析。结果表明,7个小麦籽粒品质性状的广义遗传力在62.14%~85.35%之间,由大到小排序依次为:硬度(85.35%)>湿面筋含量(78.44%)>出粉率(73.13%)>容重(72.50%)>沉降值(66.70%)>籽粒蛋白质含量(65.24%)>淀粉含量(62.14%)。在4个不同环境下,7个小麦籽粒品质性状表现为蛋白质含量、湿面筋含量、沉降值的变异相对较大,籽粒硬度的变异居中,淀粉含量、出粉率、容重的变异较小,多数籽粒品质性状间呈极显著相关性。设定阈值P<0.01,经关联分析,7个性状共检测到6605个显著性SNP标记,可解释6.021%~31.467%的变异。4个环境下检测到2个以上性状共有的多性状位点12个,可以解释6.233%~17.708%的表型变异。分别是蛋白质含量/沉降值、蛋白质含量/容重共有位点各1个,分别位于6A、2B上;蛋白质含量/湿面筋含量共有位点5个,分别位于3A、1B、6B、7B和7D上;沉降值/容重/籽粒硬度3个性状共有位点1个,位于5B上;蛋白质含量/沉降值/湿面筋含量3个性状共有位点3个,位于7A、3B和2D上,蛋白质含量/沉降值/湿面筋含量/容重4个性状共有位点1个,染色体位置未知。筛选出11个多性状、多环境品质相关基因,其中TraesCS6B01G347500编码一种储运蛋白,TraesCS1B01G395400编码碳水化合物转运蛋白/糖转运蛋白,TraesCS2D01G246500基因编码具有耐冷、耐盐、节水相关的蛋白ESKIMO1,可作为候选基因进行等位变异分析和标记开发,为小麦标记辅助选择育种提供分子工具。

冬小麦新品种陇鉴9828苗期抗条锈性遗传分析

为明确冬小麦新品种陇鉴9828苗期抗条锈性基因类型及其数量,为该品种抗病基因的合理应用提供支撑。2022年对小麦遗传群体(铭贤169/陇鉴9828)的F1、F2单株及其双亲材料的幼苗分别接种CYR34、CYR32及新菌系ZS的单孢菌系,进行抗条锈性遗传分析。结果表明,陇鉴9828苗期对条锈菌CYR34、CYR32表现中抗,对条锈菌新菌系ZS表现高抗,铭贤169表现高度感病。分别接种条锈菌CYR34、CYR32后,F1代表现感病,F2代单株抗感表现分离,符合1R:3S的分离比值;接种条锈菌新菌系ZS后,F1代表现抗病,F2代植株抗感表现分离,符合3R:1S的分离比值。说明陇鉴9828对条锈菌CYR34、CYR32的苗期抗条锈性均由1对隐性抗性基因控制,对条锈菌新菌系ZS的苗期抗病性由1对显性抗性基因控制,该研究结果可对冬小麦新品种陇鉴9828在生产和育种中应用提供参考。

基于遗传解析新模式的小麦寡分蘖QTL的鉴定和验证

有效分蘖数可直接影响小麦的成穗数,与产量关系极为密切。挖掘小麦分蘖数相关数量性状位点,解析分蘖数与其他重要农艺性状之间的相关性,可为分子育种提供理论依据。本研究首先提出和建立了“多个环境评价-单个性状深入-综合性状兼顾-友好标记开发-不同背景验证”的遗传解析新模式。进一步利用该模式,以寡分蘖自然变异植株msf和川农16(CN16)构建的F6代重组自交系群体(MC群体)为实验材料,以多年多点的有效分蘖数作为表型数据,借助基于16K芯片构建的遗传连锁图谱成功定位和验证了寡分蘖遗传调控位点。QTL定位结果显示,1A、5A和6D染色体上有4个控制寡分蘖的QTL。其中Qltn.sau-MC-1A为稳定主效的寡分蘖QTL,解释了13.39%~60.40%的表型变异,其正效应位点来源于msf。表型分析发现,携带Qltn.sau-MC-1A正效应位点株系的有效分蘖数显著少于携带Qltn.sau-MC-1A负效应位点株系的有效分蘖数。相关性分析表明,有效分蘖数和株高之间存在极显著的正相关,与千粒重、每穗粒数、每穗粒重、旗叶宽之间存在显著的负相关,有效分蘖数与旗叶长、开花期之间无显著相关。遗传分析结果表明,Qltn.sau-MC-1A正效应位点显著增加每穗粒数、每穗粒重和千粒重,但推迟开花期。不同遗传背景下的验证结果表明,携带Qltn.sau-MC-1A正效应位点的株系确实能降低有效分蘖数。综上,本研究建立了一种遗传解析新模式,并基于此模式解析、定位和验证了一个控制寡分蘖的主效QTL Qltn.sau-MC-1A,为进一步精细定位和了解分蘖形成机制奠定了基础。

一粒系小麦遗传多样性分析及抗条锈菌CYR34鉴定

一粒系小麦(Einkorn wheat,AA)作为小麦的基础物种,在形成普通小麦的过程中染色体组部分位点丢失,评价一粒系小麦的遗传多样性及对病害抗性的水平对普通小麦育种和遗传改良具有重要的理论意义和育种价值。本研究利用15对条带清晰、多态性高的SSR引物对170份一粒系小麦材料进行遗传多样性分析,并接种条锈菌流行生理小种CYR34进行抗病性评价。结果表明,SSR分析获得71个等位变异,引物平均多态性信息含量为0.6540;聚类分析和群体结构分析均将170份供试材料分为两个类群,两类群内的平均遗传距离分别为0.4732和0.5404;抗病性评价获得19份抗性较好的材料,其中免疫材料3份,近免疫材料2份,高抗1份,中抗13份,占供试材料的11.17%;有3对SSR引物与一粒系小麦抗条锈病显著相关。综上所述,一粒系小麦存在较多的等位基因变异,含有优异的抗条锈病基因,具有提高小麦抗条锈病的育种潜力。

K型小麦保持系遗传多样性的系统聚类分析

为了给K型小麦雄性不育系、保持系的选育及杂种组合选配提供依据,对25份K型小麦保持系品种的7个主要农艺性状进行了遗传多样性、相关性和聚类分析。结果表明,25份K型小麦保持系品种的7个主要农艺性状都表现出较大的变异性,变异系数从低到高依次为株高(7.12%)、千粒质量(7.49%)、每穗粒数(9.12%)、穗长(9.61%)、单株粒数(16.69%)、单株穗数(18.37%)、单株粒质量(20.61%)。相关性分析结果表明,3对性状达到了极显著正相关,分别为单株粒数与单株粒质量(相关系数r=0.732)、单株穗数与单株粒数(r=0.577)、单株粒质量与单株穗数(r=0.522);4对性状呈显著正相关,分别是千粒质量与单株粒质量(r=0.371)、穗长与每穗粒数(r=0.278)、株高与穗长(r=0.269)、穗长与单株粒数(r=0.211);2对性状呈显著负相关,分别为株高与每穗粒数(r=-0.214)、每穗粒数与单株穗数(r=-0.399)。聚类分析结果显示,25份K型小麦保持系品种的遗传距离变化范围为1.15~26.25。在遗传距离12.50处,将供试品种划分为5个类群:Ⅰ类群共有17个品种,第Ⅰ类群在遗传距离7.50处,分为3个亚类;第Ⅱ类群有1个品种,为石H09-7075,单株粒质量为8.59 g,低于其他类群;第Ⅲ类群1个品种为浚2016,株高为50.67 cm,低于其他类群;第Ⅳ类群5个品种,包括衡4568、山农0911、周麦16等,单株穗数为9.27个,多于其他类群;第Ⅴ类群为衡5011,株高为70.52 cm,高于其他类群。

小麦叶色突变体lc1的鉴定及遗传特性分析

光合作用是小麦产量形成中最重要的生理过程之一。叶色突变体直接或者间接影响叶绿体发育、叶绿素合成或代谢过程,进而导致叶片光合效率的变化。本研究以小麦品系1A520诱变得到的叶色突变体lc1(Leaf color mutation,lc1)为试验材料,进行了叶色观察、农艺性状调查、叶绿素含量测定、叶绿体超微结构观察、温度敏感性测试及遗传特性分析。结果表明:与野生型相比,突变体lc1在两叶一心期时出现叶片白化,随发育进程逐渐恢复成绿白相间的条纹状;至旗叶、倒二叶及穗子刚抽出时均呈现黄色,叶片完全展开后逐渐恢复为淡绿色。lc1在苗期时的叶绿素含量极显著低于野生型,且叶绿体缺乏板层结构。农艺性状调查发现,lc1的株高、单株有效穗数、粒长、粒宽和千粒重等极显著低于野生型,旗叶长度和穗粒数则极显著高于野生型。温敏试验表明lc1在10℃时叶绿素含量最低,为低温敏感类型。遗传分析和55K芯片分型表明,lc1的叶色表型由一对隐性核基因控制,且很可能位于7D染色体长臂。上述试验结果为lc1基因的定位和克隆奠定了基础。

小麦骨干亲本周8425B抗条锈病优异基因在其衍生品种中的遗传解析

周8425B是黄淮海麦区应用较广泛的矮秆大穗、抗病抗逆小麦骨干亲本,解析周8425B衍生品种的条锈病抗性遗传表现及其携带的抗条锈病基因遗传传递信息对新品种选用具有重要价值。本研究以条锈病强毒力生理小种条中34(CYR34)单一菌种对收集的222份周8425B衍生品种进行苗期条锈病抗性鉴定,以CYR34为主的混合菌种对衍生品种进行成株期条锈病抗性鉴定,利用周8425B携带的抗条锈病基因YrZH84、YrZH84.2、Yr30、YrZH22和Yr9紧密连锁的分子标记对衍生品种进行基因型检测。研究结果表明,周8425B苗期和成株期对目前强毒力优势菌种CYR34均表现高抗条锈病。在222份周8425B的衍生品种中,2年表现稳定成株期抗病的衍生品种有昌麦9号、济研麦10、百农4199、赛德麦7号和郑麦103等14份,占比6.3%;表现稳定全生育期抗病的衍生品种有周麦11、周麦22、周麦26、周麦36、兰天36、存麦16和郑品麦8号等52份,占比23.4%。周8425B衍生品种主要通过周麦11、周麦12、周麦13、周麦15、周麦16和周麦17等6个子一代再次衍生到子二代。子一代中周麦16和周麦13由于具有较好的农艺性状直接衍生出较多品种,周麦12与周麦13培育出子二代周麦22衍生出45个子三代,周麦11培育出矮抗58衍生出54个子三代。周8425B携带的YrZH84、YrZH84.2、YrZH22、Yr30和Yr9在衍生后代中的频率分别为34.7%、14.9%、41.9%、66.2%和67.1%。仅携带其中1个抗病基因的衍生品种以携带YrZH84的平均严重度最低,为15.4%;聚合2个抗病基因的衍生品种中,以携带YrZH84+YrZH22的平均严重度最低,为20.0%;聚合3个抗病基因的衍生品种中,以携带YrZH84+YrZH22+Yr9的平均严重度最低,为17.2%;聚合4个抗病基因的衍生品种中,携带YrZH84+YrZH22+Yr30+Yr9的平均严重度为16.9%,携带YrZH84.2+YrZH22+Yr30+Yr9的平均严重度为38.4%。苗期以携带全生育期抗性基因YrZH84或含有YrZH84的基因组合的衍生品种的抗病性较好。研究结果为中国小麦骨干种质周8425B的持续改良利用提供了条锈病基因信息,鉴定出对强毒力生理小种CYR34表现抗病的衍生新种质,为我国小麦抗条锈病遗传育种提供了参考。

149份春小麦种质资源遗传多样性分析

为筛选出高产优质的春小麦新种质资源,丰富黄土高原旱作雨养区春小麦种质资源的遗传多样性,以149份春小麦种质资源为研究对象,通过农艺性状和品质性状研究其遗传多样性,分析性状间相关性,并运用聚类分析法筛选出高产优质的春小麦种质资源。结果表明,149份春小麦种质资源的10个品质性状(籽粒灰分含量、水分含量、蛋白质含量、淀粉含量、降落数值、硬度、容重、湿面筋含量、弱化度、沉降值)的多样性指数介于1.77~2.03,平均值为1.924;5个农艺性状(小穗数、穗长、株高、单株穗数、单株产量)的多样性指数介于1.84~2.04,平均值为1.958。供试春小麦种质各性状具有丰富的多样性,且变异类型丰富,其中单株穗数与单株产量呈极显著正相关;单株产量与蛋白质含量呈极显著负相关,与淀粉含量、湿面筋含量、降落数值呈负相关。通过聚类分析,筛选出了定西53号、10102-1、Mace、EmuRock等4个性状优良且变异类型丰富的春小麦种质资源。

黄淮麦区180个小麦品种的6个农艺性状遗传多样性分析

对黄淮麦区小麦品种进行遗传多样性分析,分类、筛选农艺性状优异品种,可为拓宽黄淮麦区小麦品种的遗传基础及培育突破性新品种提供基础材料。以黄淮麦区已审定的180个小麦品种为研究群体,对其6个重要农艺性状进行变异分析、相关分析和聚类分析。变异分析结果显示,株高的变异系数(CV)最小(5.76%),说明参试品种株高差异较小,株高改良到了瓶颈期,已经没有多少下降的空间;不育小穗数的变异系数最大(41.58%),改良空间较大,改良后可有效改善结实性。相关分析结果显示,穗长与每穗小穗数和穗粒数呈极显著正相关(r分别为0.546和0.323),每穗小穗数与穗粒数呈极显著正相关(r=0.338),小麦株高与不育小穗数呈显著负相关(r=-0.213),每穗小穗数与单株有效分蘖数呈显著负相关(r=-0.242),不育小穗数与穗粒数呈极显著负相关(r=-0.361),穗粒数与单株有效分蘖数呈极显著负相关(r=-0.364)。聚类分析结果显示,180份试材分为五大类群:第一类群包括57个品种,其平均穗长和穗粒数最高,6个农艺性状CV的平均值为15.5%;第二类群包括25个品种,其平均穗长、每穗小穗数、不育小穗数和单株有效分蘖均最低,6个农艺性状CV的平均值为12.87%;第三类群包括54个品种,其平均株高最大、穗粒数最低,6个农艺性状CV的平均值为12.66%;第四类群包括34个品种,其平均单株有效分蘖数最高,6个农艺性状CV的平均值为10.39%;第五类群包括10个品种,其平均每穗小穗数和不育小穗数最高,6个农艺性状CV的平均值为15.51%。180个小麦品种的农艺性状变异较大,遗传多样性丰富,其中,第一类群有57个小麦品种,其农艺性状最优良,在小麦育种中结合育种目标可以作为骨干亲本材料;其他4个类群共123个小麦品种,个别农艺性状优良,可以作为改良另一育种材料某个欠优性状的供体亲本材料。

40个河南省审定小麦品种遗传多样性的SSR标记分析

利用小麦基因组42条染色体臂上的43个SSR标记对40个河南省审定小麦品种的遗传多样性进行了研究。结果发现,43对SSR引物中有31对(占72%)扩增出带并具有多态性,这31对引物共检测到186个等位变异,每对引物能检测到2～14个,平均位点为6个。聚类分析表明,SSR标记能将40个品种相互区分开。品种间遗传距离(GD)变幅为0.231～0.593,平均GD值为0.404。据此认为,SSR标记揭示出这40个河南省审定小麦品种遗传变异较小,遗传基础狭窄。