Puroindoline b位点近等基因系对小麦面粉及面包和馒头品质的影响

明确不同硬度等位基因与加工品质的关系对小麦品质改良具有重要意义。本文以7个Puroindoline b位点近等基因系为材料,研究了不同硬度等位基因对小麦面粉及面包和馒头品质的影响。结果表明,Pina-D1b/Pinb-D1a基因型的籽粒硬度值、蛋白质含量以及破损淀粉含量较高;而Pina-D1a/Pinb-D1d基因型的出粉率、面粉亮度较高,具有较好的磨粉品质。和面仪参数中的峰高、峰宽和8 min尾高均以Pina-D1b/Pinb-D1a基因型数值最高,Pina-D1a/Pinb-D1d 基因型最低,且两者之间的差异均达到显著水平;Pina-D1b/Pinb-D1a基因型的衰落角最小。Pina-D1a/Pinb-D1c和Pina-D1a/Pinb-D1d基因型具有较高馒头色泽和张弛性评分,较好的馒头制作品质;Pina-D1a/Pinb-D1e和Pina-D1a/Pinb-D1g基因型次之。Pina-D1a/Pinb-D1f基因型的面包总评分略优于其他基因型。     

CIMMYT普通小麦籽粒硬度等位变异的检测

籽粒硬度主要由5D染色体短臂的一对主效基因Ha控制,研究籽粒硬度等位变异有助于提高小麦的磨粉和食品加工品质。本试验对国际玉米小麦改良中心（CIMMYT）的138份历史品种和代表性高代品系的硬度基因型进行了研究。在用SDS-PAGE鉴定Pina-D1b/Pinb-D1a时,用10%甘油代替水配制分离胶,用PDA代替甲叉配制分离胶和浓缩胶,增强了PINA和PINB两种蛋白带型的分辨率。结果表明,与其他国家硬质麦中Pina-D1a/Pinb-D1b类型偏多的特点明显不同,CIMMYT硬质小麦中puroindoline a（PINA）蛋白缺失类型（或称Pina-D1b/Pinb-D1a）较多,为118个,占85.5%;Pina-D1a/Pinb-D1a（野生型）为11个,占8.0%;Pina-D1a/Pinb-D1b类型有9个,占6.5%。其中,PINA缺失对小麦籽粒硬度的影响最大,与其他2种基因型硬度值之间差异达5%显著水平。先前研究结果表明,PINA蛋白缺失类型的磨粉品质和面包烘烤品质均劣于Pina-D1a/Pinb-D1b类型,因此,建议CIMMYT多引进一些其他硬度变异类型的小麦种质,如Pina-D1a/Pinb-D1b类型等,以改善其硬度基因型过度单一的局面,从而减少PINA蛋白缺失带来的不利影响。同时,也提醒我国以其他用途如抗病、抗旱等为目的,引种CIMMYT小麦时,还应充分考虑PINA蛋白缺失对磨粉和加工品质的不利影响,以更合理引进和有效利用CIMMYT种质资源。     

Puroindoline b位点近等基因系对小麦籽粒淀粉含量和组分及其特性的影响

为了研究不同硬度等位基因与小麦籽粒淀粉组分含量及特性的关系,为小麦品质改良提供依据,以7个硬度Puroindoline b位点近等基因系为试材,研究了不同硬度基因型对小麦籽粒淀粉组分含量及特性的影响。结果表明,Pina-D1b/Pinb-D1a基因型的籽粒硬度值、支链淀粉含量最高;Pina-D1b/Pinb-D1a基因型的淀粉溶解度最高,而Pina-D1a/Pinb-D1d溶解度最低,两者差异达显著水平;不同基因型之间籽粒淀粉酶解力没有显著差异;冻融失水率以基因型Pina-D1a/Pinb-D1b最低,表明Pina-D1a/Pinb-D1b基因型冻融稳定性最好,可能较适宜冷冻食品的制作;对于抗性淀粉,Pina-D1a/Pinb-D1b基因型的抗性淀粉含量最高、Pina-D1a/Pinb-D1d最低,表明Pina-D1a/Pinb-D1b基因型有助于籽粒中抗性淀粉含量的提高。     

小麦籽粒硬度基因型鉴定及其与吹泡仪和混合仪参数关系分析

以我国黄淮麦区35份小麦高代新品系为材料,通过测定其籽粒硬度表型、puroindoline基因型及其吹泡仪和混合仪参数,分析了籽粒硬度表型和基因型与吹泡仪和混合仪参数间的关系。结果发现,SKCS籽粒硬度与混合仪参数中的C1、C2、C3、C4值、幅度、吸水率、C3-C2值以及吹泡仪参数的P值、L值、G值和P/L值之间均极显著相关(P < 0.01)。方差分析表明,puroindoline基因对大多数吹泡仪和混合仪参数的影响极显著(P < 0.01)。其中,Pina-D1b类型小麦品系的P值、W值和P/L值均显著高于野生型和Pinb-D1b类型,但野生型小麦品系的L值、G值和Ie值则均显著高于Pinb-D1b和Pina-D1b类型。另外,2种硬质基因型(Pinb-D1b和Pina-D1b)小麦品系的C1值、C2值、C2-C1值、幅度和吸水率均显著高于野生型,而野生型小麦品系的C3值、C4值和C5值则显著高于2种硬质基因型。     

新疆小麦籽粒硬度Puroindoline b相关基因等位变异的分子检测

Puroindoline b-2(Pinb-2)基因与籽粒硬度基因Puroindoline b序列高度相似,与小麦籽粒硬度及其产量性状密切相关。本研究以3个籽粒硬度基因(Pina-D1,Pinb-D1和Pinb-2)的特异性功能标记对新疆99份冬小麦和24份春小麦品种(系)进行分子标记检测。在123份新疆小麦品种(系)中Pina-D1和Pinb-D1基因位点Pina-D1a、Pina-D1b、Pinb-D1a和Pinb-D1b等位变异的频率分别为85.4%、14.6%、57.7%和42.3%;在Pinb-2位点,39.0%的小麦品种含Pinb-2v2(低千粒重)等位基因,61.0%的小麦品种含Pinb-2v3(高千粒重)等位变异。在3个位点基因型组合分析表明,在所检测的新疆小麦种质中共有6种基因型组合,其中2种软质麦基因型Pina-D1a/Pinb-D1a/Pinb-2v2,Pina-D1a/Pinb-D1a/Pinb-2v3和3种硬质麦Pina-D1a/Pinb-D1b/Pinb-2v2、Pina-D1a/Pinb-D1b/Pinb-2v3、Pina-D1b/Pinb-D1a/Pinb-2v2、Pina-D1b/Pinb-D1a/Pinb-2v3,其分布频率分别为19.5%、22.8%、13.05%、30.1%、6.5%和8.1%。新疆冬小麦共有5种基因型组合,在不同类型冬麦资源中,具有高千粒重的软质麦类型Pina-D1a/Pinb-D1a/Pinb-2v3的分布频率大小顺序为地方品种(52.9%)自育品种(25.6%)引进品种(12.8%),与之相反,具有较高千粒重的硬质麦类型Pina-D1a/Pinb-D1b/Pinb-2v3和PinaD1b/Pinb-D1a/Pinb-2v3的分布频率大小顺序为:引进品种(53.8%)自育品种(32.5%)地方品种(5.9%);新疆春小麦共有6种基因型组合,在不同类型春麦资源中,具有高千粒重的软质麦类型Pina-D1a/Pinb-D1a/Pinb-2v3的分布频率大小顺序为:早期品种(20.0%)晚期品种(10.5%),与之相反,具有较高千粒重的硬质麦类型Pina-D1a/Pinb-D1b/Pinb-2v3和Pina-D1b/Pinb-D1a/Pinb-2v3的分布频率大小顺序为:晚期品种(47.4%)早期品种(45.8%)。新疆小麦以硬质麦为主,在软冬麦、硬冬麦、软春麦和硬春麦中均是具有Pinb-2v3(高千粒重)等位变异类型的分布频率高于具有Pinb-2v2(低千粒重)等位变异类型。将3个位点特异性标记结合起来使用,不仅能有效的应用于小麦与籽粒硬度改良,同时能应用于小麦产量性状改良方面。     

山东小麦籽粒硬度演变规律研究

利用单籽粒谷物特性测试仪和PCR扩增、酶切及DNA测序技术,结合改良的friabilin提取及电泳分析方法,对山东省431份农家品种、63份历史品种和29份当前主栽品种的籽粒硬度分布以及Pina和Pinb等位变异类型进行研究,以探讨山东小麦籽粒硬度的演变规律。农家品种、历史品种和当前主栽品种中硬质麦比例分别为75.6%、12.7%和27.6%,混合麦分别占20.4%、19.0%和13.8%,而软质麦分别占3.9%、68.3%和58.6%。农家品种中共有6种基因型,Pina-D1b/Pinb-D1a和Pina-D1a/Pinb-D1p分别占硬质麦的38%和59.6%。历史品种中有4种基因型,8份硬质麦中Pina-D1b/Pinb-D1a占37.5%,Pina-D1a/Pinb-D1b占37.5%,而Pina-D1a/Pinb-D1p只占25.0%。当前主栽品种中,8份硬质麦全部是Pina-D1a/Pinb-D1b类型。长芒透垅白等3个品种的Pinb基因的核苷酸序列发生了双突变,起始密码子下游96 bp处碱基C突变为A,而且在265 bp处发生了A碱基的缺失,将其命名为Pinb-D1aa。     

中国黄淮麦区小麦籽粒硬度Puroindoline基因等位变异检测

籽粒硬度是小麦品质性状改良的重要目标之一,研究黄淮麦区核心种质资源小麦籽粒硬度基因型分布规律,能够为中国小麦品质改良和种质资源利用提供信息。以来自中国黄淮麦区的244份小麦核心种质为材料,采用单籽粒谷物特性测试仪和特异引物的PCR扩增对其SKCS硬度及其基因型进行鉴定。结果表明,黄淮麦区小麦核心种质资源以硬质类型为主,占总参试材料的56.6%,其硬质麦基因型共有Pina-D1b、Pina-D1r、Pina-D1s、Pina-D1l、Pinb-D1b、Pinb-D1p、Pinb-D1ac、Pinb-D1e、Pinb-D1t和Pinb-D1u共10种单倍型,其分布比例分别为2.1%、5.3%、4.5%、0.8%、25.8%、15.7%、0.4%、0.4%、0.8%和0.8%。可以看出,Pinb-D1p在参试材料硬质麦中占据主导地位,PINA蛋白缺失类型也有广泛的分布。不同来源小麦品种籽粒硬度基因型分布表明,山西、河南、云南和新疆小麦品种籽粒硬度基因型较为丰富。不同类型小麦品种籽粒硬度基因型分布表明,农家种小麦籽粒硬度基因型更为丰富。在各Puroindoline变异类型中,拥有PINA-null类型的小麦品种SKCS籽粒硬度显著高于拥有Pinb-D1b和Pinb-D1p类型的小麦品种。本项研究表明黄淮麦区核心种质资源具有丰富的籽粒硬度主效基因变异类型,结合先前研究中认为的PINA-null类型的磨粉品质和面包烘烤品质均劣于Pinb-D1b类型,但拥有相对较好的印度薄饼加工品质,因此品质育种过程中可依据育种目标有选择的利用黄淮麦区小麦核心种质资源。     

北方冬麦区新育成优质小麦品种面条品质相关性状分析

为了解近年北方冬麦区育成优质小麦品种的品质状况,两年两点统一种植52份优质品种(系)及6份国外代表性品种,测定其磨粉品质、和面仪和混合实验仪特性、淀粉糊化特性及面条品质,并利用5个基因特异性标记分析基因型分布及其对品质性状的影响。结果表明,大部分品种为硬质、中强筋类型,品种间出粉率、面粉a*值、b*值、黄色素含量、PPO活性、和面仪参数、混合实验仪形成时间和稳定时间差异较大。和面仪8 min带宽和混合实验仪稳定时间可作为预测面条品质的重要指标,可分别解释面条总分变异33.3%和34.4%。Ppo-A1a和Ppo-A1b频率为41.4%和58.6%,两种基因型间PPO活性差异显著(P<0.05);Ppo-D1a和Ppo-D1b频率为51.7%和48.3%,但PPO活性差异不显著;Psy-A1a和Psy-A1b频率为81.0%和19.0%,两种基因型间黄色素含量差异显著(P<0.05);1BL/1RS易位和非易位品种频率为13.8%和86.2%,两种基因型间面粉L*值、黄色素含量、和面仪衰落势与8 min带宽、混合实验仪稳定时间等差异显著(P<0.05)。面条品质较好的品种包括Sunzell、石优17、郑麦366、中麦 895、周麦 26、CA1004和石4185。本研究明确了58份小麦品种(系)的品质特征和基因型分布,为优质小麦新品种选育和推广提供了重要信息。     

不同面粉对鲜白盐面条颜色的影响

为了研究不同面粉对鲜白盐面条颜色的影响，在澳大利亚商业面粉中添加一定量的淀粉、面筋粉和麦芽，配制了8种面粉，用其制成鲜白盐面条后，用Minolta在0和24h时分别测量其L*、a*、b*值。经分析，在0和24h时，8种面条的L*、a*、b*值都分别达到显著或极显著水平；在24h后，所有面条的颜色变差，其L*值降低，a*、b*值升高；经比较，在添加了淀粉的面条颜色较好，其中以面条CK+9%S（在面粉中添加9%淀粉）的颜色最好。结果建议育种家在优质面条小麦育种中，应注意选出的品种蛋白质含量不应高，而淀粉含量应较高和面条颜色稳定性好的抗穗发芽品种。     

CIMMYT新型人工合成小麦Pina和Pinb基因等位变异

六倍体人工合成小麦由硬粒小麦（Triticum turgidum subsp. durum）与粗山羊草（Aegilops tauschii Coss.）杂交产生,是研究小麦进化过程中基因变异的重要材料。以国际玉米小麦改良中心（CIMMYT）提供的57份由野生二粒小麦（T. turgidum subsp. dicoccoides）与粗山羊草杂交产生的新型人工合成六倍体小麦为材料，用单籽粒特性测定仪和Pina、Pinb特异性PCR引物对其籽粒硬度变异以及控制籽粒硬度的主效基因Pina和Pinb的分布情况进行了研究。结果表明，这些材料的SKCS硬度值变异较大，从10.5到42.6，其中15~30的占78%。共有Pina-D1a、Pina-D1c、Pinb-D1h和Pinb-D1j 4种等位变异型，基因型为Pina-D1a/Pinb-D1j的8个，占14%；基因型为Pina-D1c/Pinb-D1h的49个，占86%。方差分析表明，基因型Pina-D1a/Pinb-D1j与Pina-D1c/Pinb-D1h对籽粒硬度的影响差异不显著，但父本粗山羊草和母本野生二粒小麦以及二者间的互作对籽粒硬度有显著影响，说明除Pina和Pinb外，还有其他微效基因影响籽粒硬度的形成。     

Prevalence of a novel puroindoline b allele in Yunnan endemic wheats (Triticum aestivum ssp. yunnanense King)

Grain hardness is a major factor influencing the classification and end-use quality of bread wheat. In this study, 40 Yunnan endemic wheats, 21 historical cultivars and 66 current cultivars and advanced lines were investigated for kernel hardness and puroindoline alleles using molecular and biochemical markers. The frequencies of soft, mixed and hard genotypes were 10.0%, 5.0% and 85.0%, respectively, in Yunnan endemic wheats, whereas the corresponding frequencies were 47.6%, 23.8% and 28.6% in historical cultivars, and 36.3%, 6.1% and 57.6% in current cultivars and advanced lines. Four known puroindoline alleles, Pina-D1b, Pinb-D1b, Pinb-D1d and Pinb-D1e, were found in the hard wheat cultivars. Compared with endemic wheats and historical cultivars, current cultivars from Yunnan province have relatively high frequencies of Pina-D1b and Pinb-D1b alleles at 43.5% and 16.1%, respectively. All 32 hard Yunnan endemic wheats (Triticum aestivum ssp. yunnanense King) contained a new puroindoline b allele, designated Pinb-D1u, that was characterized as a single nucleotide (G) deletion at position 127 in the coding sequence of the Pinb gene, leading to a shift of the open reading frame (ORF) from position 14 in the deduced amino acid sequence and a stop codon corresponding to position Leu-18. The average SKCS hardness of genotypes with Pina-D1b (68.2) is significantly higher than those of Pinb-D1b (60.3) and Pinb-D1u (60.5). The study of puroindoline alleles in Yunnan germplasm could provide useful information for improving processing quality and further understanding the molecular basis of kernel hardness in bread wheat.     

Evaluation of maternal parent and puroindoline allele on kernel texture in a reciprocal cross between two hard spring wheat cultivars

Kernel texture is an important characteristic for both the milling and the end-use quality of wheat (Triticum aestivum L.). Gene sequence variation and mutations to the two puroindoline genes (Pina and Pinb), located at the Ha locus on chromosome 5DS, account for the majority of variation in wheat kernel texture. Other factors also influence kernel texture, including effects associated with different maternal parent backgrounds. To investigate the effect of two hard puroindoline alleles in different maternal backgrounds, a population of 228 recombinant inbred lines (RILs) derived from a reciprocal cross between two wheat cultivars ID377s (Pina-D1b/Pinb-D1a) and Klasic (Pina-D1a/Pinb-D1b) were examined in two succeeding generations (F₇ & F₈). Kernel texture was determined using the Single Kernel Characterization System (SKCS) and the RIL puroindoline haplotype was identified by the sequence-specific PCR amplification of each gene. Analysis of variance identified a significant (P 0.001) effect of the maternal parent and puroindoline mutation on kernel texture. RILs containing the Pina-D1b mutation were significantly harder than lines containing the Pinb-D1b mutation. RILs which had Klasic as the maternal parent were significantly harder than those which had ID377s as the maternal parent. When the maternal parent and puroindoline allele were analyzed in combination, RILs derived from Klasic as the maternal parent and the Pina-D1b allele were significantly harder (P 0.001) than those containing the same allele but ID377s as the maternal parent. The same occurred for RILs containing the Pinb-D1b allele, lines with Klasic as the maternal parent were harder than lines with ID377s as the maternal parent. These results corroborate the harder phenotype of the Pina-D1b allele and indicate a significant maternally-inherited contribution to kernel texture variation.     

Molecular characterization of <Emphasis Type="Italic">Pina</Emphasis> and <Emphasis Type="Italic">Pinb</Emphasis> allelic variations in Xinjiang landraces and commercial wheat cultivars

Grain hardness plays an important role in determining both milling performance and quality of the end-use products produced from common or bread wheat. The objective of this study was to characterize allelic variations at the Pina and Pinb loci in Xinjiang wheat germplasm for further understanding the mechanisms involved in endosperm texture formation, and the status of grain texture in Chinese bread wheat. A total of 291 wheat cultivars, including 56 landraces, and 95 introduced and 140 locally improved cultivars, grown in Xinjiang, were used for SKCS measurement and molecular characterization. Among the harvested grain samples, 185 (63.6%), 40 (13.7%), and 66 (22.7%) were classified as hard, mixed and soft, respectively. Eight different genotypes for the Pina and Pinb loci were identified, including seven previously reported genotypes, viz., Pina-D1a/Pinb-D1a, Pina-D1a/Pinb-D1b, Pina-D1b/Pinb-D1a, Pina-D1a/Pinb-D1p, Pina-D1a/Pinb-D1q, Pina-D1a/Pinb-D1aa, Pina-D1a/Pinb-D1ab, and a novel Pinb allele, Pinb-D1ac. This new allele, detected in Kashibaipi (local landrace) and Red Star (from Russia) has a double mutation at the 257th (G to A substitution) and 382nd (C to T substitution) nucleotide positions of the coding region. Pina-D1b, Pinb-D1b, and Pinb-D1p were the most common alleles in Xinjiang wheat germplasm, with frequencies of 14.3%, 38.1% and 28.6% in hard textured landraces, 25.5%, 56.9% and 11.8% in hard introduced cultivars, and 24.8%, 47.8% and 26.5% in hard locally improved cultivars, respectively. The restriction enzymes ApaI, SapI, BstXI and SfaNI were used to identify Pinb-D1ab or Pinb-D1ac, Pinb-D1b, Pinb-D1e and Pinb-Dg, respectively, by digesting PCR products of the Pinb gene. The unique grain hardness distribution in Xinjiang bread wheat, as well as the CAPs markers for identification of the Pinb alleles provided useful information for breeding wheat cultivars with optimum grain textures. Liang Wang and Genying Li—contributed equally to this work.     

加工过程对小麦及其制品中玉米赤霉烯酮含量的影响

真菌毒素(mycotoxin)是小麦及面制食品重要的安全风险之一。为明确真菌毒素在小麦磨粉及食品加工链条中的变化规律,解决目前我国尚缺少面粉和面制食品真菌毒素限量标准的问题,开展小麦真菌毒素污染风险评估,以受玉米赤霉烯酮(ZEN)污染的小麦为材料,用超高效液相色谱串联质谱法(UPLC-MS/MS)检测了不同磨粉组分及馒头、面包、面条加工过程中不同环节加工品中ZEN的含量。结果表明,小麦磨粉后粗麸皮和细麸皮中ZEN的含量显著升高,达到小麦籽粒的2倍以上,小麦粉中ZEN的含量平均降低70%以上;小麦粉加工成馒头和面包后,ZEN的含量分别增高1.8倍和1.0倍,加工成面条后因ZEN在煮制过程中部分溶于水中而降低30%以上。研究结果表明,加工过程对小麦及面制食品中的毒素水平有显著影响,对小麦、面粉及不同的小麦制品分别制定ZEN限量更为科学合理。