CIMMYT种质及育种技术在四川小麦品种改良中的利用

1966年,第一份CIMMYT育成小麦品种Penjamo 62引入四川,1989年中国和CIMMYT签订小麦穿梭合作育种协议、四川被指定为我国3个春麦穿梭点之一。之后,四川开始较为系统地利用CIMMYT种质和育种新技术,以提高四川小麦育种水平,加速四川小麦新品种选育步伐。在这一漫长过程中,我们深刻体会到,CIMMYT真正对四川小麦育种最具影响力的是三个方面:引进有用种质;提供育种新技术和新思路;科学家交流及对青年专家的培训。如何才能在四川小麦育种中充分发挥和有效利用CIM-MYT的这些优势去提高四川小麦的育种水平?我们的基本做法是:加大CIMMYT种质在四川生态下的筛选力度;以我院原有小麦育种项目及积累的育种材料为基础,有针对性地选择冬春杂交、穿梭育种、改良混合选择和微效多基因持久抗性等CIMMYT育种新技术及新思路,结合已较为成熟的DH群体及重组自交系群体等分子技术,构建新的育种体系;由于生态条件的巨大差异,坚持以引进改良、自育创新为主,CIMMYT/四川//四川及冬/春//春已证明是利用CIMMYT种质资源较好的杂交模式;以熟悉四川育种及CIMMYT育种的专家及在CIMMYT接受过培训的青年专家为核心,组成目标明确、分工合作的育种及科研团队,并坚持不懈,是成功利用CIMMYT种质及技术的基础;加大双方科学家互访及对青年科学家的培训力度和信息资料的及时交流,增进双方科学家对对方育种理念、生态环境、育种资源、技术经验以及育种材料的田间长相等的更深刻认识和体验,从而增强双方工作的针对性与互动性,这是有效利用CIMMYT种质及技术经验的成功保证。截至2006年,选用CIMMYT种质由四川育种家育成的小麦新品种已达19个,其中有3个还通过了国家品种审定,一个是世界上首次利用CIMMYT人工合成种育成的商用小麦新品种。这批新品种在四川表现出三方面的突出优势:为四川输入了一批条锈病新抗源;使四川首次在强筋小麦育种上获得突破;打破了四川小麦育种单产水平长期徘徊的局面,创造了四川小麦高产育种新水平;预期在近几年内,将有更多用CIMMYT种质育成的小麦新品种在四川审定推广。这表明,CIMMYT小麦种质及育种新技术已成为四川小麦品种改良与创新中不可或缺的重要因素。广适应型高产育种材料及品种的创制与遗传机理研究(可用川麦42为基础)、条锈病持久抗性材料及品种研制与新抗源筛选转育(以现有持久抗性和四川核心资源为基础)、四川生态下优质稳定表达材料的筛选转育以及高产优质的节约环保型简化栽培体系开发,将是四川与CIMMYT进一步深化合作的主要技术方向,而继续强化对青年专家的培训和科学家间加强专项合作及对现场交流、指导,将是进一步取得成功与成果的重要保证。

CIMMYT小麦材料的苗期和成株抗叶锈病鉴定

选择来自CIMMYT的103个小麦品种(系)及35个含有已知抗叶锈基因的对照品种,苗期接种17个中国小麦叶锈菌小种以鉴定这些品种中可能含有的抗叶锈病基因,并于2008—2009和2009—2010连续2年对这些材料进行成株抗叶锈病鉴定。通过苗期鉴定结合系谱分析和分子检测,在46个品种中鉴定出Lr26、Lr34、Lr42和Lr47共4个抗叶锈病基因,其中9个品种携带Lr26基因,28个品种含有成株抗叶锈病基因Lr34基因,Lr42可能存在于11个品种中,还有2个材料可能含有Lr47,其他57个品种(系)对供试的15个小种多数表现为高抗,没有鉴定出已知的抗叶锈病基因。通过2年的田间抗叶锈病鉴定共筛选出46个表现慢锈的品种。苗期和田间结果表明,CIMMYT材料中含有丰富的对我国叶锈菌小种有效的苗期和成株抗叶锈基因,这些材料均可应用于我国小麦的抗叶锈病育种。

CIMMYT种质对四川、云南、甘肃和新疆春性小麦产量遗传增益的贡献

研究历史品种产量潜力变化规律有助于提高小麦育种水平。2007—2009连续2年度将来自四川、云南、甘肃和新疆的代表性59个品种分别种植在四川成都、云南丽江、甘肃武威和新疆昌吉,在肥水供应充足、控制病虫害和倒伏的条件下分析了产量和相关农艺性状的变化趋势。结果表明,四川、云南、甘肃和新疆品种的产量随育成年份显著增加,年遗传增益分别为0.73%、0.34%、0.58%和1.43%。产量遗传增益四川品种表现与产量构成因子关系不密切;云南品种主要表现为减少穗数和增加穗粒数;甘肃品种主要表现为增加穗粒数;新疆品种主要表现为增加主穗粒重和收获指数,并与成熟期提早及株高降低有一定关系。各地区品种中Rht-B1b和Rht-D1b矮秆基因均来自CIMMYT种质,其产量潜力的提高主要得益于CIMMYT种质的引进和有效利用,在四川和云南,CIMMYT种质的主要贡献是提高品种的条锈病抗性;而在甘肃和新疆,其被利用的主要特性是矮秆、高产、穗粒数多及广泛适应性。

CIMMYT小麦在中国春麦区的适应性分析

目的研究CIMMYT小麦在中国的适应性有助于提高春麦区的育种水平。方法10份CIMMYT代表性品种和15份中国春麦主栽品种于2001和2002年种植在中国春麦区的9个试点和CIMMYT的4种不同处理环境,分析产量、产量构成因子和农艺性状的变化趋势。结果CIMMYT品种穗数和穗粒数多,千粒重中等,具有广泛适应性,比中国品种具有更高的产量优势;黑龙江光敏感品种植株高、抽穗和成熟晚、穗数中等、穗粒数少、千粒重和产量低;中国其它品种株高中等、抽穗和成熟早、穗数少、穗粒数中等、千粒重高、产量中等。CIMMYT品种引种到中国后,株高降低,抽穗和成熟提早,并略减产;黑龙江光敏感品种在CIMMYT种植时株高增加,抽穗和成熟推迟,千粒重降低,并显著减产;中国其它品种在CIMMYT种植时株高增加、抽穗和成熟略推迟、千粒重变化较小,并略减产。结论CIMMYT品种可在云南、青海和新疆直接推广种植;内蒙古、甘肃和宁夏为其次适宜地区,可以直接推广应用,但主要用作杂交亲本;在黑龙江以作杂交亲本为宜。为提高引种效率,并考虑到性状的重复力大小,在CIMMYT为中国选种时应重点选择籽粒较大的材料。为云南所选材料可略矮、适当晚熟,内蒙古、甘肃、宁夏和新疆所选材料可略高、较早熟,青海所选材料可较高、熟期相当,黑龙江应主要选择高纬度材料、植株偏高且晚熟。

中国和CIMMYT小麦品种Bx7亚基超量表达基因(Bx7^OE)的分子检测

高分子量谷蛋白亚基Bx7的超量表达对提高小麦面筋强度有重要作用。利用反相高效液相色谱(RP-HPLC)和STS标记检测了163份中国和CIMMYT小麦品种(系)的高分子谷蛋白亚基Bx7超量表达基因(Bx7OE)。结果表明,TaBAC1215C06-F517/R964标记和TaBAC1215C06-F24671/R25515标记可分别在含有Bx7OE基因的材料中扩增出447bp和844bp的特异带,在不含Bx7OE基因的材料中无相应目标带,两个STS标记的检测结果完全一致。在163份小麦品种(系)中,11份品种(系)含有Bx7OE基因,占总数的6.7%。RP-HPLC与STS标记检测结果一致。利用这两个STS标记可以方便、快速、准确地检测Bx7OE基因。

CIMMYT小麦在我国的产量和品质表现

为了研究近年来国际玉米小麦改良中心(CIMMYT)育成的小麦品种的产量、品质等性状及其在我国春麦区的表现,选用新引进的10个CIMMYT小麦新品种和我国15个主栽春小麦品种,在国内9个试点进行了两年联合多点试验。结果表明,CIMMYT小麦新品种对我国中西部地区适应性较好,在产量和品质方面总体表现较我国品种好,其中大多数品种具有优质高分子量谷蛋白亚基(HMW-GS),沉淀值较高,对叶锈病抗性突出。今后在继续提高产量的同时,应把改良我国小麦的加工品质和抗病性作为重点,开展对CIMMYT小麦种质的直接和间接利用研究。

CIMMYT和中国硬质春麦在4种CIMMYT不同处理环境中产量和蛋白品质性状分析

灌溉、播期和垄作等栽培方式对小麦产量和蛋白品质性状具有重要影响。将21个中国和CIMMYT硬质春麦品种于2000—2001和2001—2002年度分别种植在CIMMYT的Obregon试验站4种处理环境中。结果表明,所有性状均受品种和处理环境的显著影响,产量和沉降值同时还受品种和处理环境互作效应的显著作用,在进行产量和品质改良时应考虑品种与处理环境间的互作。充分灌溉和适期播种有利于提高产量,减少灌溉迟播垄作则有利于提高蛋白含量和沉降值。Rayon F89产量、蛋白含量和沉降值均较高;龙麦26产量、蛋白含量和沉降值显著高于其他光敏感品种。充分灌溉适期播种垄作利于提高Rayon F89等的产量和Weaver等的沉降值,充分灌溉适期播种平播利于提高Seri M82等的产量和Attila等的沉降值,充分灌溉迟播垄作利于提高龙麦26等的产量和Super Seri#1等的沉降值,减少灌溉适期播种垄作则利于提高Rayong F89等的产量和Weaver等的沉降值。

Progress Towards Genetics and Breeding for Minor Genes Based Resistance to Ug99 and Other Rusts in CIMMYT High-Yielding Spring Wheat

Wheat rusts continue to cause significant losses worldwide despite major efforts given to their genetic control. This is due to frequent evolution and selection of virulence in pathogen overcoming the deployed race-specific resistance genes. Although the life of effective race-specific resistance genes can be prolonged by using gene combinations, an alternative approach being implemented at CIMMYT is to deploy varieties that posses adult plant resistance （APR） based on combinations of minor, slow rusting genes. When present alone, the APR genes do not confer adequate resistance especially under high disease pressure; however, combinations of 4 or 5 minor genes usually result in ＂near-immunity＂ or a high level of resistance. Although only a few APR genes are catalogued, various APR QTLs are now known and could lead to further characterization of additional genes. Four characterized genes have pleiotropic effects in conferring partial APR to all 3 rusts and powdery mildew, thus simplifying the task of breeding wheat varieties that are resistant to multiple diseases. Significant progress was made recently in developing high-yielding wheat germplasm that possesses high levels of APR to all three rusts by implementing a Mexico- Kenya shuttle breeding scheme. Parents with APR to Ug99 were hybridized with high-yielding parents that had adequate to high levels of APR to leaf rust and yellow rust. Segregating populations and advanced lines from these crosses were selected under high rust pressures in Mexico （leaf rust and yellow rust） and Kenya （Ug99 stem rust and yellow rust） to identify high- yielding progenies that possess high to adequate APR to all three rusts. International distribution of these high-yielding wheats is underway through CIMMYT intemational yield trials and screening nurseries. It is expected that several wheat varieties with APR to three rusts will be released and grown in various countries in the near-future that will allow determining the durability of resistance.

玉米须多糖的理化性质和体外生物活性研究

为探讨玉米须多糖含量及体外生物活性,采用热水浸提-醇沉法提取3个品种(‘黑金699’‘金银308’和‘夏王’)玉米须多糖,并对其理化性质和体外生物活性进行对比。结果表明:‘黑金699’‘金银308’和‘夏王’3个品种玉米须多糖含量分别为(32.57±0.12)mg∕g、(96.39±0.76)mg∕g和(27.48±0.63)mg∕g。理化性质研究表明,3个品种玉米须多糖主要由阿拉伯糖、半乳糖和葡萄糖组成,且分子量大小分布不同。红外光谱分析表明,3个品种玉米须多糖均为β构型的酸性吡喃多糖。体外活性研究表明,3个品种玉米须多糖具有良好抗氧化、降血糖和抗肿瘤活性,且呈剂量依赖性,其中‘黑金699’玉米须多糖表现最为优异。综上,3个品种玉米须多糖具有较好的生物活性,该研究可为其在功能性食品、药品和化妆品中的应用提供依据。

Genome-wide association mapping and genomic prediction of stalk rot in two mid-altitude tropical maize populations

Maize stalk rot reduces grain yield and quality.Information about the genetics of resistance to maize stalk rot could help breeders design effective breeding strategies for the trait.Genomic prediction may be a more effective breeding strategy for stalk-rot resistance than marker-assisted selection.We performed a genome-wide association study(GWAS)and genomic prediction of resistance in testcross hybrids of 677 inbred lines from the Tuxpe?o and non-Tuxpe?o heterotic pools grown in three environments and genotyped with 200,681 single-nucleotide polymorphisms(SNPs).Eighteen SNPs associated with stalk rot shared genomic regions with gene families previously associated with plant biotic and abiotic responses.More favorable SNP haplotypes traced to tropical than to temperate progenitors of the inbred lines.Incorporating genotype-by-environment(G×E)interaction increased genomic prediction accuracy.

The wheat sucrose synthase gene TaSus1 is a determinant of grain number per spike

Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions.

Remote sensing of quality traits in cereal and arable production systems:A review

Cereal is an essential source of calories and protein for the global population.Accurately predicting cereal quality before harvest is highly desirable in order to optimise management for farmers,grading harvest and categorised storage for enterprises,future trading prices,and policy planning.The use of remote sensing data with extensive spatial coverage demonstrates some potential in predicting crop quality traits.Many studies have also proposed models and methods for predicting such traits based on multiplatform remote sensing data.In this paper,the key quality traits that are of interest to producers and consumers are introduced.The literature related to grain quality prediction was analyzed in detail,and a review was conducted on remote sensing platforms,commonly used methods,potential gaps,and future trends in crop quality prediction.This review recommends new research directions that go beyond the traditional methods and discusses grain quality retrieval and the associated challenges from the perspective of remote sensing data.

Genetic improvement of wheat grain quality at CIMMYT

The International Maize and Wheat Improvement Center(CIMMYT) is the global leader in publiclyfunded maize and wheat research and in farming systems based on these crops.CIMMYT leads the Global Wheat Program(GWP), which includes some of the largest wheat breeding programs in the world.The GWP has been successful in developing wheat germplasm that is used extensively worldwide.Wheat quality improvement is a central component of all the breeding efforts at CIMMYT and the Wheat Chemistry and Quality Laboratory represents an integral part of the breeding programs.Wheat quality is addressed at CIMMYT over the full range of this very wide and variable concept with milling,processing, end-use and nutritional quality targeted.Wheat progenitors and advanced lines developed by the breeders are assessed for diverse quality attributes, with the aim of identifying those that fulfill the requirements in terms of milling, processing, end-use and nutritional quality in different target regions.Significant research is conducted to make more efficient the integration of wheat quality traits in the breeding programs.The main topics being addressed are(1) methodologies to analyze grain quality traits,(2) genetic control and environmental effects on quality traits,(3) characterization of genetic resources for quality improvement, and(4) diversifying grain properties for novel uses.

China-CIMMYT collaboration enhances wheat improvement in China

China and CIMMYT have collaborated on wheat improvement for over 40 years and significant progress has been achieved in five aspects in China.A standardized protocol for testing Chinese noodle quality has been established with three selection criteria, i.e.,gluten quality, starch viscosity and flour color are identified as being responsible for noodle quality.Genomic approaches have been used to develop and validate genespecific markers, leading to the establishment of a KASP platform, and seven cultivars have been released through application of molecular marker technology.Methodology for breeding adult-plant resistance to yellow rust, leaf rust and powdery mildew, based on the pleiotropic effect of minor genes has been established, resulting in release of six cultivars.More than 330 cultivars derived from CIMMYT germplasm have been released and are now grown over 9% of the Chinese wheat production area.Additionally, physiological approaches have been used to characterize yield potential and develop high-efficiency phenotyping platforms.CIMMYT has also provided valuable training for Chinese scientists.Development of climate-resilient cultivars with application of new technology will be the priority for future collaboration.

品种及地理位置对糯玉米糊化特性和食味品质影响

本研究以198个糯玉米主栽品种为材料,从适宜种植区角度测定了糯玉米淀粉糊化特征值和食味品质,并分析二者相关关系。结果表明,品种对糊化特征值的影响最大,峰值黏度、崩解值、终值黏度、回复值等糊化特征值基本呈正态分布,80%的材料峰值黏度集中在2300~3000 cP,超过3000 cP有16个品种。峰值黏度、谷值黏度、崩解值、终值黏度、回复值间为极显著正相关,与糊化时间、糊化温度呈极显著负相关。东南区的食味品质总评分最高,为86.8分,显著高于西南区、黄淮海区和东华北区,而西南区、黄淮海区、东华北区间差异不显著。峰值黏度、谷值黏度和崩解值与食味品质总分呈正相关且相关系数均在0.753以上,可用于评价糯玉米食味品质优劣。

优质蛋白玉米研究进展

玉米是世界三大粮食作物之一,其中优质蛋白玉米(QPM)的赖氨酸和色氨酸含量明显高于普通玉米,具有较高的蛋白质品质,其营养价值也明显高于普通玉米。本文综述了赖氨酸含量调控基因和胚乳修饰基因的研究进展,以及国内外优质蛋白玉米的研究概况,并对优质蛋白玉米研究进行了展望。

营养型糯玉米新品种‘申科糯601’的选育及营养成分分析

‘申科糯601’是以SWL05为母本,SWL10为父本组配而成的糯玉米杂交新品种。为更好地推广该品种,以‘申科糯601’为研究对象,对其产量、营养成分、综合农艺性状进行研究分析。结果表明:在‘申科玉(东南区)鲜食玉米品种联合体试验中,2020年,‘申科糯601’平均鲜穗产量12310.5 kg∕hm^(2),2021年,平均鲜穗产量12505.5 kg∕hm^(2);该品种生育期77.7 d左右。品尝品质综合评分87.6分,皮渣率9.5%,支链淀粉占总淀粉的百分比为97.9%。营养成分分析显示,‘申科糯601’的叶酸含量为218.82μg∕(100 g),维生素C含量为1.063 mg∕(100 g);VE总含量是0.284 mg∕(100 g),包括δ-VE、γ-VE和α-VE,其含量分别是0.009、0.205、0.070 mg∕(100 g);叶黄素、玉米黄质和β-胡萝卜素含量分别是1.403、0.057、0.003 mg∕(100 g),赖氨酸含量为0.35 g∕(100 g),比对照高40%,微量元素K、P、Mg、Ca、Fe、Zn、Na、Al、Cu、Mn、Ni、Cr和Co的含量分别为195.963、146.564、57.660、4.554、1.441、0.969、0.741、0.631、0.302、0.271、0.052、0.018 mg∕(100 g)和0.016 mg∕(100 g)。

爆裂玉米分子育种研究进展

爆裂玉米是一种用于生产爆米花的重要经济作物。爆裂玉米的主要育种目标是在保证膨爆品质的前提下提高产量、抗性等农艺性状。近年来,分子标记技术极大地促进了爆裂玉米重要性状的分子机制解析。分子育种策略是将遗传学和基因组学的最新研究成果与传统育种策略相结合,在未来的爆裂玉米品种开发中具有广阔的应用前景。本文对爆裂玉米不同性状的分子生物学研究进行总结,为我国爆裂玉米分子育种实践提供理论参考。

甜玉米RIL群体籽粒可溶性糖相关性状的QTL定位

以甜玉米自交系SHL01和SHL03为亲本构建RIL群体,对乳熟期籽粒的葡萄糖、果糖、蔗糖性状进行QTL定位。结果表明:共检测出3个QTL位点,位于玉米的2、6、7号染色体上,其中1个葡萄糖QTL为q GLU2,2个蔗糖QTL为q SUC6、q SUC7,解释表型变异的7.24%—15.30%,主效QTLq GLU2、q SUC6能够分别解释15.30%和10.80%表型变异。本研究结果可为进一步精细定位葡萄糖、果糖、蔗糖性状基因,利用分子标记辅助育种改良甜玉米甜味品质性状奠定基础。

化肥减施对鲜食糯玉米产量和品质的影响

试验设置5个施肥处理即不施肥(CK)、单施化肥(F1)、减施20%化肥+微生物菌肥(F2)、减施30%化肥+微生物菌肥(F3)、减施50%化肥+微生物菌肥(F4),研究化肥减施对糯玉米‘沪红糯1号’产量及品质的影响。结果表明:F2处理的鲜穗产量和经济效益最高,较CK分别增加2388 kg∕hm^(2)、26157.6元(人民币,下同)∕hm^(2),增幅为18.41%、17.06%。与F1处理相比,F2、F3、F4处理降低了土壤p H和含盐量,降幅分别为6.3%、6.6%、7.8%和28.2%、31.1%、40.2%。F2处理的粗脂肪、粗淀粉含量最高,分别为6.3%、6.6%,较CK显著提高9%和58.5%。综上,化肥减施+微生物菌肥处理可提高糯玉米产量、籽粒品质和经济效益,改善土壤理化性质,其中,F2处理效果较好。