湖北推广小麦品种(系)高分子量麦谷蛋白亚基组成分析

应用SDS-PAGE技术分析了45份湖北推广小麦品种(系)籽粒的高分子量麦谷蛋白亚基组成。40份材料的高分子量麦谷蛋白亚基组成为同质,5份为异质。在Glu-1位点共检测到9种等位基因变异类型,其中Glu-A1位点有“1、2^ 、Null”3种变异类型,Glu-B1位点有“7、7 8、7 9、14 15”4种,Glu-D1位点有“2 12、5 10”2种。“Null、7 8、2 12”是主要亚基,它们的频率分别是62．5％、60％和72．5％。亚基组合类型有12种,其中(Null,7 8,2 12)亚基组合占30．0％,(1,7 8,2 12)、(1,14 15,2 12)、(Null,7 9,2 12)、(Null,7 8,5 10)4种组合的频率都在10％以上,这5种亚基组合占总组合的72．5％。供试小麦材料品质评分在5～10之间,平均评分为7．0。含5 10亚基的品种(系)所占比例低,是湖北小麦烘烤品质较差的部分原因。     

小麦加工品质相关贮藏蛋白、基因及其遗传改良研究进展

随着小麦以及相关近缘种属基因组测序的完成,各类分子生物学技术应用于小麦品质相关蛋白基因的研究越来越多,新蛋白和新基因的发现为小麦品质遗传改良提供了更大的研究空间。本文简要概述了传统贮藏蛋白的研究现状,着重介绍了目前新发现的与小麦加工品质相关的贮藏蛋白和基因的研究进展,从遗传改良的角度上提出目前存在的问题及发展方向,以期为我国小麦品质研究提供有价值的理论参考,促进品质研究更好的应用于小麦育种的实践。     

不同施肥灌水处理对不同小麦品种产量和品质的影响

在小麦生育期间降水47.9 mm的条件下,以3个小麦品种为试验材料,采用四因素三水平正交设计,研究了不同灌水和施肥处理对不同小麦品种子粒产量、蛋白质含量和沉降值的影响。结果表明,全生育期施氮量300 kg/hm2和225 kg/hm2的处理子粒产量和蛋白质含量差异不显著,但均显著高于150kg/hm2的处理。在中产条件下氮肥底施和追施比例以7∶3时产量最高。春季灌4水产量显著高于灌2水的处理,但与灌3水差异不显著,子粒蛋白质含量以灌2水时最高。供试品种中以京冬8号的产量、千粒重、容重最高,CA0206和核优1的蛋白质含量差异不显著,但均显著高于京冬8号。CA0206的沉降值显著高于另两个品种。以产量、品质和经济效益综合考虑,在本试验条件下,以春季灌3水、施氮量225 kg/hm2、底施和追施比例为7∶3的处理为宜,与超高产条件下氮素底施和追施比例5∶5的结果有明显的差异。     

山东小麦种质资源品质特性多样性研究及利用

连续2年对698份地方品种、育成品种和省外引进品种的淀粉糊化特性、面团揉混特性和面筋蛋白特性等进行了详细的研究,并对不同生态类型区地方品种的品质特性进行了分析。结果表明:(1)不同来源种质资源品质特性表现出一定差异,育成品种和省外引进品种具有较长的面团揉混形成时间和较高的沉淀值,形成时间超过3.5min的品种分别有10和16个,最高值达5.2min;沉淀值水平较高,超过40.0ml的品种分别有32和25个,最高值分别为61.8ml和68.8ml;地方品种表现出较好的淀粉RVA糊化特性和较高的面筋蛋白含量,峰值粘度大于2900cP的有24个,最高峰值粘度高达4099cP,沉淀值在40.0ml以上的品种占48.8%,最高值达58.8ml;(2)不同生态类型区地方品种具有不同的品质特性,胶东丘陵冬性晚熟类型区烟台和青岛的地方品种具有较好的淀粉RVA糊化特性和较高的面筋蛋白含量,鲁西北平原冬性/半冬性晚熟类型区滨州、潍坊和德州的地方品种具有较好的淀粉RVA糊化特性,鲁中山丘川半冬性/冬性中熟类型区临沂、泰安的地方品种具有较高的面筋蛋白含量;(3)筛选出形成时间大于4.5min且沉淀值高于50.0ml的育成品种济南17、济宁16、济麦20、洲元9369和泰麦一号等,沉淀值超过60.0ml的省外引进品种藁优9415、冀5099、临汾6410和临汾6510等,峰值粘度高于3100cP的地方品种半截芒、白秃头(二)、三八麦、白秃头、小白芒(2)、半截红穗,以及沉淀值高于50.0ml的地方品种蚂蚱头、白肚、白气死雾、一穗收、四棱白、白穗红、半截红穗等,这些材料均可作为培育优质小麦的首选亲本。     

Characterization of SNP and Structural Variations in the Mitochondrial Genomes of Tilletia indica and Its Closely Related Species Formed Basis for a Simple Diagnostic Assay

Tilletia indica causes the disease Karnal bunt in wheat. The disease is under international quarantine regulations. Comparative mitochondrial (mt) genome analysis of T. indica ({"type":"entrez-nucleotide","attrs":{"text":"KX394364","term_id":"1128620031","term_text":"KX394364"}}KX394364 and {"type":"entrez-nucleotide","attrs":{"text":"DQ993184","term_id":"115361453","term_text":"DQ993184"}}DQ993184) and T. walkeri ({"type":"entrez-nucleotide","attrs":{"text":"EF536375","term_id":"144925993","term_text":"EF536375"}}EF536375) has found 325 to 328 SNPs, 57 to 60 short InDels (from 1 to 13 nt), two InDels (30 and 61 nt) and five (>200 nt) presence/absence variations (PAVs) between the two species. The mt genomes of both species have identical gene order. The numbers of SNPs and InDels between the mt genomes of the two species are approximately nine times of the corresponding numbers between the two T. indica isolates. There are eight SNPs between T. indica and T. walkeri that resulted in amino acid substitutions in the mt genes of cob, nad2 and nad5. In contrast, there is no amino acid substitution in the mt genes of the T. indica isolates from the SNPs found. The five PAVs present in T. indica ({"type":"entrez-nucleotide","attrs":{"text":"DQ993184","term_id":"115361453","term_text":"DQ993184"}}DQ993184) are absent in T. walkeri. Four PAVs are more than 1 kb and are not present in every T. indica isolate. Analysis of their presence and absence separates a collection of T. indica isolates into 11 subgroups. Two PAVs have ORFs for the LAGLIDAG endonuclease and two have ORFs for the GIY-YIG endonuclease family, which are representatives of homing endonuclease genes (HEGs). These intron- encoded HEGs confer intron mobility and account for their fluid distribution in T. indica isolates. The small PAV of 221 bp, present in every T. indica isolate and unique to the species, was used as the genetic fingerprint for the successful development of a rapid, highly sensitive and specific loop mediated isothermal amplification (LAMP) assay. The simple procedure of the LAMP assay and the easy detection formats will enable the assay to be automated for high throughput diagnosis.     

小麦农艺性状与品质特性的多元分析与评价

估算96个小麦品种(系)的11个农艺性状和10个品质特性参数的主成分,并以主成分和欧氏距离为基础,分别作二维排序分析和聚类分析。农艺性状的前4个主成分反映了85.3450%的原始数据信息量;品质特性的前4个主成分代表了89.1483%的原始数据信息量。以96个材料的主成分得分绘制二维排序图,27个小麦品种(系)表现为矮秆、子粒和旗叶较大,丰产性较好、综合农艺性状优良;32个小麦品种(系)表现为铁、锌含量较高,加工品质较好、综合品质特性优良。在系统聚类图中,农艺性状和品质特性分别被聚成5类。综合农艺性状较好的材料主要集中在第Ⅲ类和第Ⅳ类;综合品质特性较好的材料主要集中在第Ⅰ类和第Ⅱ类。综合分析发现,同时兼顾丰产性较好且子粒铁、锌含量较高,品质特性较好的小麦品种(系)有:泰山9818、西农822、轮选719、杨-31、西安837和中育9383。将聚类分析和二维排序分析结合起来,能较好的对小麦的性状组成做出综合评价,鉴定和评价出优质、高产、综合性状优良的小麦品种(系),为小麦遗传育种提供优良的种质资源,为合理选配亲本提供参考。     

小偃6号及其衍生后代品质相关性状基因的分子检测

小偃6号是我国小麦育种的重要骨干亲本之一。本研究利用UMN19、UMN25、UMN26、T2、T5、T13、S13、S1、T1、Wx-A1、Wx-B1、Wx-D1、YP7A、YP7B-1、PPO18、PPO29等16个功能型分子标记对小偃6号及其衍生后代的品质相关性状的基因组成进行了检测和分析。结果表明:在高分子量谷蛋白亚基两位点(Glu-A1、Glu-D1)和Waxy蛋白基因位点上,分别有78.72%、82.98%的衍生品种与骨干亲本小偃6号等位基因一致,但少数品种具有不同的优良亚基等位基因Ax2*或Dx5+Dy10;在低分子量谷蛋白亚基两位点(Glu-B3、Glu-D3)上,有25.33%的衍生品种与小偃6号等位基因一致;在八氢番茄红素合成酶基因位点Psy-A1、Psy-B1和多酚氧化酶(PPO)活性等位基因位点上,仅有17.02%和38.29%的衍生品种与小偃6号一致;并探讨了不同品质相关性状基因位点在衍生后代传递频率存在差异的原因。     

灌水时期和灌水量对小麦氮代谢相关酶活性和籽粒蛋白质品质的影响

以高产强筋小麦品种'济麦20'为试验材料,在防雨池栽条件下研究了灌水时期和灌水量对小麦氮代谢相关酶活性和籽粒蛋白质品质的影响.结果表明,随灌水时期增多和总灌水量增加,小麦开花后旗叶硝酸还原酶活性和谷氨酰胺合成酶活性显著增高,旗叶蛋白质水解酶内肽酶(EP)、氨肽酶(AP)、羧肽酶(CP)活性降低;小麦籽粒清蛋白和球蛋白含量增加,而籽粒谷蛋白和醇溶蛋白含量、成熟期籽粒谷醇/清球比值(谷蛋白+醇溶蛋白含量/清蛋白+球蛋白含量)降低;面粉沉降值和面团稳定时间显著降低,籽粒产量显著增加.研究发现,在本试验条件下,小麦全生育期灌水3次处理(底墒水+拔节水+开花水)在灌浆前中期旗叶NR和GS活性、灌浆中后期旗叶EP、CP、AP 活性均较高,且成熟期籽粒蛋白质含量、谷醇/清球比值、面团稳定时间、籽粒产量亦较高,是获得小麦高产优质的最佳灌水处理.     

Tests for Positive Selection on Immune and Reproductive Genes in Closely Related Species of the Murine Genus <Emphasis Type="Italic">Mus</Emphasis>

Abstract We examine variation among species of Mus in four genes involved in reproduction and the immune response for evidence of positive selection: the sperm recognition gene Zp-3, the testis-determining locus Sry, the testicular cell surface matrix protein Tcp-1, and the immune system protein β₂ m. We use likelihood ratio tests in the context of a well-supported phylogeny to determine whether models that allow for positively selected sites fit the sequences better than models that assume purifying selection. We then apply a Bayesian approach to identify particular sites in each gene that have a high posterior probability of being under positive selection. We find no evidence of positive selection on the Tcp-1 gene, but for Zp-3, Sry, and β₂ m, models that allow for positively selected sites fit the sequences better than alternatives. For each of these genes, we identify sites that have a high (> 95%) posterior probability of being positively selected. For Zp-3, two of these sites occur near the sperm-binding region, while one occurs in a region whose functional role remains unstudied but where the pattern of change predicts functional importance. A single site in Sry shows an elevated rate of replacement substitution but occurs in a region of apparently little functional importance; therefore, relaxation of functional constraints may better explain the rapid evolution of this site. Three sites in β ₂ m have a posterior probability > 50% of being under positive selection. While the functional role for two of these sites is unknown, the third is known to influence the ability of MHC class I molecules to present antigens to the immune system; therefore, the elevated rate of replacement substitutions at this site is consistent with selection acting to promote variability in immune system proteins.