摘要
遗传多样性是生物多样性的基本组成部分，是种内不同群体之间或同一群体内部不同个体之间遗传差异的总和。研究物种的遗传多样性，不仅可以为遗传资源的收集与保存工作提供理论指导，还可以为物种的起源、进化和分类的研究以及核心种质的构建提供重要的理论依据。同时，对资源的有效利用也具有十分重要的意义。
本文围绕着“五十年来黄淮冬麦区选育品种的遗传多样性变化及核心种质的构建”等问题，利用SSR的分子标记技术，主要研究了以下两个基本问题：首先，以96份随机样品为材料，探讨了客观反映品种间遗传关系所需的最少SSR位点数(等位变异数)；其次，以该区选育品种的448份初选核心种质样品为材料，研究了黄淮冬麦区选育品种的遗传多样性结构及其五十年来的多样性变化，并探讨了其核心种质的构建问题。得到以下主要结论：
1．客观反映小麦品种间的遗传关系至少需要73个多态性较好的SSR位点，位点的选取必须覆盖小麦A、B、D基因组的所有21条染色体。样本的大小对所需位点数的影响甚微。
2．我国小麦地方品种与选育品种是两个相对独立的遗传群体，地方品种的遗传多样性明显地高于选育品种。
3．在我国普通小麦的遗传资源中，虽然B基因组拥有最高的遗传多样性，但地方品种与选育品种之间的遗传差异可能主要存在于D基因组，地方品种在D基因组中拥有较多的特异性等位变异。
4．黄淮冬麦区选育品种间存在着较大的遗传差异，其遗传相似系数的平均值仅为0.329．五十年来，黄淮冬麦区完成了5-6次品种更换，小麦品种的遗传结构发生了很大变化。从整体上看，80年代以前育成的品种，其遗传多样性和品种间的遗传差异都有一个不断上升的趋势；80年代育成的品种其平均等位变异丰富度还呈上升趋势，但其遗传离散系数和品种间的遗传差异却呈下降趋势；到了90年代，其育成品种的遗传多样性和品种间的遗传差异均存在一个较为明显的下降趋势，其品种间的平均遗传距离已急剧下降到0.650，应引起我们的注意。
5．从各种取样方法保留等位变异的效果看，建立在聚类图基础上的随机取样法和定向取样法都可以建立较好的核心种质，而定向地选取拥有年代特异等位变异品种的取样方法效果则更好，但是这种取样方法可能会丢失部分重要育种材料或生产品种，如果能在其基础上补充进这部分材料或品种，则可取得更令人满
意效果。
6.建立了195个品种的黄淮冬麦区选育品种的核心种质。此核心种质具有
很好的代表性，它保留了该区选育品种93.3%的遗传多样性:其基本包含了该区
选育品种的全部重要育种材料和生产品种，以及许多特异的遗传材料，包括许多
矮秆材料、早熟材料、大穗资源、多穗资源、抗逆抗病品种。
Genetic diversity is the fundamental element of biodiversity, including the genetic differentiation between populations in a species and the genetic variation among individuals within a population. Genetic diversity research is helpful for collection, conservation and efficient utilization of the genetic resources. It is also useful for studying the origin, evolution and classification of species.
Two main problems were focused on in this paper. Firstly, the minimum number of SSR loci (alleles) needed to reveal the genetic relationships in wheat varieties was investigated with 96 random samples. Secondly, genetic diversity of 448 candidate core collections of modern varieties was assayed, which were released in Yellow and Huai River Valley Winter Wheat Region in the past half century. The major conclusions are following.
1. More than 73 highly informative SSR loci are needed to reveal the genetic relationships realistically in wheat varieties. The SSR loci must cover all of the 21 chromosomes of wheat. Sample size has no evident effect on the loci needed.
2. Chinese modern varieties and the landraces are two relatively independent populations. Genetic diversity of the landraces is much higher than that of the modern varieties.
3. B genome showed the highest genetic diversity among the three genomes in Chinese common wheat. However, the main genetic differentiation between the landraces and the modern varieties existed in the D genome. The D genome of the landraces conveys more specific alleles.
4. High genetic differentiation exists in the modern varieties released in Yellow and Huai River Valley Winter Wheat Region since 1949. Their average genetic similarity index is only 0.329. In the past five decades, the genetic diversity of the modern varieties in this region changed strongly due to the 5-6 times of variety replacements. Genetic diversity increased before 1980s, which was supported by changes of average genetic richness, Simposon index and average genetic distance among varieties released in each decade. Average allelic richness of the varieties reached the highest in varieties released in
1980s. However, since this time, the average genetic dispersion indices among varieties have decreased. In varieties released in 1990s, both average allelic variation and Simposon index significantly decreased. We should pay attention to this phenomenon.
5. Evaluation by the ability to keep allelic variation shows that a good core collection can be developed by random sampling or directed sampling based on the dendrogram of SSR data. Directed sampling based on decade-specific alleles can keep more variation, but the core collection developed by this sampling strategy may discard some important varieties having taken essential role in production and breeding. Therefore, a perfect core can be built if these varieties can be added to.
6. A core collection of 195 entries was developed for the modern varieties in Yellow and Huai River Valley Winter Wheat Region. This core collection, which covers 93.3 percent of the genetic diversity of the modern varieties in this region, is a high-quality core. It holds all of the important varieties in production and breeding and many specific germplasms such as dwarf materials, early ripening varieties, and many varieties with large spikes or muti-spikelets, and varieties with stress resistance or resistance to diseases.
引文
董玉琛．生物多样性及生物遗传多样性检测，1995．作物品种资源．3：1-5
董玉琛，郑殿升主编，1998．中国小麦遗传资源．北京：中国农业出版社
董玉琛，曹永生，张学勇，刘三才，王兰芬，游光霞，庞斌双，李立会，贾继增，2003．中国普通小麦初选核心种质的产生．植物遗传资源学报，4(1)：1-8
郝晨刚，王兰芬，董玉琛，尚勋武，张学勇，2003．我国西北春麦区小麦育成品种遗传多样性的AFLP分析．植物遗传资源学报，第4期(待发表)
金善宝主编，1983．中国小麦品种及其系谱．北京：中国农业出版社
金善宝主编，1996．中国小麦学．北京：中国农业出版社，
金善宝主编，1986．中国小麦品种志(1962-1982)．北京：中国农业出版社
金善宝主编，1997．中国小麦品种志(1983．1993)．北京：中国农业出版社
兰海燕，2002．中国地方小麦的遗传多样性研究．中国农业科学院硕士论文
李光蓉，杨足君，畅志坚，2000．山西小麦品种(系)的高分子量谷蛋白亚基遗传变异分析．四川农业大学学报，18：113-117
李硕碧，单明珠，李必运，2002．陕西省小麦品种资源高分子量谷蛋白亚基组成．西北农林科技大学学报(自然科学版)，30：1-4
李自超，张洪亮，孙传清，王象坤，1999．植物遗传资源核心种质研究现状与展望．中国农大学报，4(5)：1-12
李自超，张洪亮，曾亚文，杨忠义，申时全，孙传清，王象坤，2000．云南地方稻种资源核心种质取样方案研究．中国农业科学，33(5)：1-7
刘爱峰，宋健民，刘建军，吴祥云，李豪圣，赵振东，2002．山东小麦品种高分子量谷蛋白亚基遗传变异分析．山东农业科学，5：3-6
刘丽，2003．高低分子量麦谷蛋白亚基等位变异和1B／1R易位与小麦加工品质性状关系的研究．中国农业科学院硕士论文
刘三才，郑殿升，曹永生，宋春华，陈梦英，2000．中国小麦选育品种与地方品种的遗传多样性．中国农业科学，33(4)：20-24
刘三才，曹永生，郑殿升，宋春华，陈梦英，2001．普通小麦核心种质抽样方法的比较．麦类作物学报．21(2)：42-45
马冬云，朱云集，郭天财，王晨阳，2002．河南省21个小麦品种(系)高分子量谷蛋白亚基的电泳分析．华北农学报，17(3)：29-32
马志清，郑有良，魏育明，吴卫，周永红，刘登才，兰秀锦，2002．四川主栽小麦品种遗传多样性的SSR标记分析．麦类作物学报，22(2)：5-9
钱曼懋，丁寿康，宋春华，1982．我国小麦品种资源的利用和发展．作物品种资源，1：26-31
钱曼懋，孙洪伟，宋春华，杨欣明，1989．北方冬小麦品种农艺性状演变研究．作物品种资源，1：3-5
孙传清，李自超，王象坤，2001．普通野生稻和亚洲栽培稻核心种质遗传多样性的检测研究．作物学报，27(3)：313-318
申时全，曾亚文，李自超，杨忠义，张洪亮．王象坤，李华俊，2001．云南稻种核心种质抗旱性研究．中国农业科学，17(5)：6-8
沈裕虎，王海庆，黄相国，窦全文，葛菊梅，张怀刚，2002．数量性状水平上甘、青两省小麦品种间的遗传多样性现状及演变趋势．西北植物学报，22：1056-1065
温之雨，张艳敏，李辉，蒋春志，丁占生，郭北海，2002．河北省高分子量谷蛋白亚基遗传变异分析，华北农学报，17(增刊)：98-102
闫长生，何中虎，周桂英，1995．我国与美国小麦品种主要农艺和品质性状的比较．中国农业科学，13(6)：37-39
晏月明，茹岩岩，余建中，刘广田，Prodanovic S，2000．中国小麦品种醇溶蛋白Gli-1和Gli-2编码位点等位基因组成分析．农业生物技术学报，8(1)：23-27
张学勇，杨欣明，董玉琛，1995．醇溶蛋白电泳在小麦种质资源遗传分析中的应用．中国农业科学，28(4)：25-32
张学勇，董玉琛，游光霞，王兰芬，李培，贾继增，2001．中国小麦大面积推广品种及骨干亲本的高分子量谷蛋白亚基组成分析．中国农业科学，34(4)：355-362
张学勇，庞斌双，游光霞，王兰芬，贾继增，董玉琛，2002．中国小麦品种资源Glu-1位点组成概况及遗传多样性分析．中国农业科学，35：1302-1310
张延滨，祁适雨，肖志敏，辛文利，1998．黑龙江省小麦品种的HMW麦谷蛋白亚基组
成和血缘关系的研究Ⅰ．70年代以前主要小麦品种的HMW麦谷蛋白亚基组成的研究．东北农业大学学报，29：111-116
张延滨，1999．黑龙江省主要小麦品种及品系的HMW麦谷蛋白亚基组成分析．哈尔滨师范大学自然科学学报，15(3)：93-97
张志清，郑有良，魏育明，吴卫，周永红，刘登才，兰秀锦，2002a．四川主栽小麦品种高分子量高蛋白亚基遗传变异分析．麦类作物学报，22(1)：14-18
张志清，郑有良，魏育明，吴卫，周永红，刘登才，兰秀锦，2002b．四川主栽小麦品种遗传多样性的SSR标记研究．麦类作物学报，22(2)：5-9
朱列层，唐国顺，Hazen SP，Kim HS，Ward RW，1999．用RFLP方法研究陕西省主要小麦品种遗传多样性及其演变．西北植物学报，19：208-213
庄巧生主编，2002．中国小麦品种改良及系谱分析．北京：中国农业出版社
Ahmad M, 2002. Assessment of genetic diversity among wheat genotypes as determined by simple sequence repeats. Genome, 45:646-651
Balfourier F, Oliveira JA, Charmet G, Arbones E, 1997. Factorial regression analysis of genotype by environment interaction in ryegrass populations, using both isozyme and climatic data as covariates. Euphytica, 98:37-47
Barrett BA. Kidwell KK, 1998. AFLP-based genetic diversity assessment among wheat cultivars from the Pacific Northwest. Crop Sci, 38:1261-1271
Basigalup DH, Barnes DK, Stucker RE, 1995. Development of a core collection for Pernnial Medicago Plangt Introductions. Crop Sci, 35:1163-1168
Bayaa B, Erskine W, Singh M, 1997. Screening lentil for resistance to fusarium wilt methodology and sources of resistance. Euphytica, 98:69-74
Bhattacharjee R, Bramel P J, Hash CT, Kolesnikova-Allen MA, Khairwal IS, 2002. Assessment of genetic diversity within and between pearl millet landraces. Theor Appl Genet, 105:666-673
Bisht IS, Mahajan RK, Loknathan TR, Gautam PL, Mathur PN, Hodgkin T, 1999. Assessment of genetic diversity, stratification of germplasm accessions in diversity groups and sampling strategies for establishing a core collection of Indian sesame (Sesamum indicum L.).Plant Genetic Resources Newsletter, 119:35-46
Brancourt-Hulmel M, Doussinault G, Lecomte C, Be'rard P, Le Buanec B, Trottet M, 2003. Genetic Improvement of Agronomic Traits of Winter Wheat Cultivars Released in France from 1946 to 1992. Crop Sci, 43:37-45
Bretting PK, Widrlechner MP, 1995. Genetic markers and plant genetic resource management. In Julea Janick(eds.) Plant breeding Review, John Wiley & Sons, Inc. USA, 13:11-18
Brown AHD, Grace JP and Speer SS, 1987. Designation of a "core" collection of perennial Glycine. Soybean Genetics Newsletter, 14:59-70
Brown AHD, 1989. Core collections: a practical approach to genetic resources managenent. Genome, 31:818-824
Brown AHD, Spillane C, 1999. Implementing core collections-principles, procedures, progress, problems and promise. In: Johnson RC, Hodgkin T (eds.) Core collections for today and tomorrow, International Plant Genetic Resources Institute, Italy, 10-17
Cao W, Hull P, Scoles G, Chibbar RN, 1998. Genetic diversity within spelta and macha wheats based on RAPD analysis, Euphytica, 104:181-189
Charmet G, Balfourier F, Ravek C, Denis JB, 1993. Genotype x environment interactions in a collection of French perennial ryegrass populations. Theor Appl Genet, 86:731-736
Charmet G, Balfourier F, 1995. The use of geostatistics for sampling a core collection of perennial ryegrass populations. Genetic Resources and Crop Evolution, 42: 303-309
Chdstiansen M J, Andersen SB, Ortiz R,. 2002. Diversity changes in an intensively bred wheat germplasm during the 20th century. Molecular Breeding, 9(1): 1-11
Ciaffi M, Dominici L, Lafiandra D, 1997. Gliadin polymorphism in wild and cultivated einkorn wheats. TheorAppl Genet, 94:68-74
Ciaffi M, Dominici L, Lafiandra D, Dominici L, Lafiandra D, 1998. High molecular weight glutenin subunit variation in wild and cultivated eikorn wheats (Triticum spp., poaceae). Plant Systematics and Evaluation, 209:123-137
Cupta PB, Khan K, Macritchie F, 1993. Biochemical basis of flour properties in bread wheat. Ⅰ. Effects of variation in the quantity and size distribution of polymeric protein. J Cereal Sci, 18:23-41
Devos KM, Gale MD, 1992. The use of random amplified polymorphic DNA markers in wheat. Theor Appl Genet, 84:567-572
Dice LR, 1945. Measures of the amount of ecologic association between species. Ecology, 26:297-302.
Diwan N, Bauchan GR, Mcintosh MS, 1994. A core collection for the United States annual Medicago germplasm collection. Crop Sci, 34:279-285
Diwan N, Mclntosh MS, Bauchan GR, 1995. Methods of developing a core colledtion of annual Medicago species. TheorAppl Genet, 90:755-761
Ellis PR, Pink DAC, Phelps K, Jukes PL, Breeds SE, PinnegarAE, 1998. Evaluation of a core collection of Brassica oleracea accessions for resistance to Brevicoryne brassicae, the cawage aphid. Euphytica, 103:149-160
Erskine W, and Muehlbauer FJ, 1991. AIIozyme and morphological variability, outcrossing rate and core collection formation in lentil germplasm. Theor Appl Genet, 83:119-125
Fahima T, Rder MS, Wendehake K, Kirzhner VM, Nevo E, 2002. Microsatellite
polymorphism in natural populations of wild emmer wheat, Tdticum dicoccoides, in Israel. Theor. Appl Genet, 104:17-29
Frankel OH, 1984. Genetic perspectives of germplasm conservation. In Arber W, Limensee K, Peacock WJ and Starlinger P (eds.), Genetic ,Manipulation: Impact on Man and Society, Cambridge University Press, Cambridge, 161-170
Frankel OH. and Brown AHD, 1984. Plant genetic resources today: a critical appraisal. In Holden JHW and Williams JT (eds.) Crop Genetic Resources: Conservation & Evaluation, George Allen & Urwin Ltd. London. 249-257
Fregene M, Bernal M, Duque M, Dixon A, Tohme J, 2000. AFLP analysys of African cassava (Manihot esculenta Crantz) germplasm resistant to the cassava mosaic disease (CMD). TheorAppl Genet, 100:678-685
Ghislain M, Zhang DP, Fajardo D, Huamán Z, Hijmans R J, 1999. Marker-assisted sampling of the cultivated Andean potato Solanum phureja collection using RAPD markers. Genetic Resources and Crop Evaluation, 46:547-555
Grenier C, Hamon P, BrameI-Coxm, 2001, Core collection of sorghum: Ⅱ.comparison of three random sampling strategies. Crop Sci, 41:241-246
Gupta PK, Balayan HS, Sharma PC, Ramesh B, 1996. Microsatellites in plants: a new class of molecular markers. Curr Sci, 70:45-54
Harberd NP, Barrels D, Thompson RD, 1986. DNA restriction fragment variation in the gene family encoding high-molecular-weight (HWM) glutenin subunits of wheat. Biochem Genet, 4:579-596
Herbert Wieser, 2000. Comparative investigations of gluten proteins from different wheat species Ⅰ. Qualitative and quantitative composition of gluten protein types. Eur Food Res Technol, 211:262-268
Hintum Th JL Van, Haalman D, 1994. Pedigree analysis for composing a core collection of modern cultivars, with examples from barley (Hordeum vulgare S lat.). Theor Appl Genet, 88:70-74
Hintum Th JL Van, Bothmer R Von, Visser DL, 1995. Sampling strategies for composing a core collection of cultivated barley (Hordeum vulgare S. lat.) collected in China. Hereditas, 122:7-17
Hintum Th JL Van, 1995. Hierarchical approaches to the analysis of genetic diversity in crop plants. In: Hodgkin T, Brown AHD, Hintum Th JL van and Morales EAV (eds.) Core Collections of Plant Genetic Resources. International Plant Genetic
Resources Institute, Italy. 23-34
Hintum Th JL Van, 1999. The general methodology for creating a core collection. In: Johnson RC, Hodgkin T(eds.) Core collections for today and tomorrow, International Plant Genetic Resources Institute, Italy, 10-17
Hintum Th JL Van, Brown AHD, Spillane C, Hodgkin T (eds), 2000. Core collections of plant genetic resources, International Plant Genetic Resources Institute, Italy, 4-50
Holbrook CC, Anderson WF, Pittman RN, 1993. Selection of a core collection from the U.S. germplasm collection of peanut. Crop Sci, 33:859-861
Holbrook CC, Anderson WF, 1995. Evaluation of a core collection to identify resistance to late leafspot in peanut. Crop Sci, 35:1700-1702
Holbrook CC, 1999. Testing and utilization of a core collection for the US germplasm collection of peanut.In: Johnson RC, Hodgkin T (eds.) Core collections for today and tomorrow, International Plant Genetic Resources Institute, Italy, 68-73
Huang X, Brner A, Ridder MS, Ganal MW, 2002. Accessing genetic diversity of wheat (Triticum aestivum L) germplasm using microsatellite markers. TheorAppl Genet, 105:699-707
Hu J, Zhu J, Xu H, 2000. Methods of constructing core collections by stepwise clustering with three sampling strategies based on the genotypic values of crops. Theor Appl Genet, 264-268
Igartau E, Gracia MP, Lasa JM, Medina B, Molina-Cano JL, Montoya JL, Romagosa I, 1998. The Spanish barley core collection. Genet Resour Crop Evol, 45:475-481
Jaradat AA, 1997. Wild emmer wheat in Jordan: Ⅲ. A core collection. Israel Joumal of plant sciences, 45(1):45-51
Johansson E, Henriksso P, Sevensson G, 1993. Detection chiomosomal location and evolution of the function value of a novel high molecular weight subunit found in Swedish wheat. J Cereal Sci, 17:237-245
Jung HG, Sheaffer CC, Barnes DK, Halgerson JL, 1997. Forage quality variation in the U.S. alfalfa core collection. Crop Sci, 37:1361-1366
Kim HS, Ward RW, 1997. Genetic diversity in Eastern U.S. soft winter wheat (Triticum aestivum L.em.Thell) based on RFLP and coefficients of parentage. Theor Appl Genet, 94:472-479
Kim HS, Ward RW, 2000. Patterns of RFLP-based genetic diversity in germplasm pools of common wheat with different geographical or breeding program origins.
Euphytica, 115:197-208
Li C, Rossnagel BG, Scoles G J, 2000. The development of oat microsatellite markers and their use in identifying relationships among Avena species and oat varieties. .Theor Appl Genet, 101:1259-1268
Li Z, Zhang H, Zeng Y, Yang Z, Shen S, Sun C, Wang X, 2002. Studies on sampling schemes for the establishment of core collection of rice landraces in Yunnan, China. Genetic Resources and Crop Evaluation, 49:67-74
Liu F, Sun G, Salomon B, Von Bothmer R, 2001. Distribution of allozymic alleles and genetic diversity in the American barley core collection. Theor Appl Genet, 102:606-615
Magurran AE, 1988. Ecological diversity and its measurement. New Jersey: Princeton University Press
Manifesto MM, Schlatter AR, Hopp HE, Suárez EY, Dubcovsky J, 2001. Quantitative evaluation of genetic diversity in wheat germplasm using molecular marker. Crop Sci, 41:682-690
Metakovsky EV and Branlard G, 1998, Genetic diversity of French common wheat germplasm based on gliadin alleles, TheorAppl Genet, 96:209-218
Miklas PN, Delorme R, Hannan R, Dickson, 1999. Using a subsample of the core collection to identify new sources of resistance to white mold in common bean. Crop Sci, 39:569-573
Nei M, 1973. Analysis of gene diversity in subdivided populations. Proc Natl Acad Sci USA, 70:3321-3323
Nei M, Li WH, 1979. Mathematical Model for studying genetic variation in terms of restriction endonucleases. Proc Nat Acad Sci USA, 76:5256-5273
Noirot M, Hamon S and Anthony F, 1996. The principal component scoring: a new method of constituting a core collection using quantitative data. Genet Resour and Crop Evol, 41:1-6
Ortiz R, Ruiz-Tapia EN, Mujica-Sanchez A, 1998. Sampling strategy for a core collection of Peruvian quinoa germplasm. TheorAppl Genet, 96:475-483
Payne PI, Corfield KG, Blackman JA, 1979. Identification of a high molecular weight subunit of glutenin whose presence correlated with breadmaking quality in wheat of pedigree. TheorAppl Genet, 55:153-159
Payne PI, Holt LM, Lawrence G J, Law CN, 1982. The genetic of gliadins and glutenin,
the major storage protein of the wheat endosperm. Qual plant, Plant Foods Hum Nutr, 31:229-331
Payne PI, Lawrence G J, 1983. Catalogue of alleles for the complex gene loci Glu-A1, Glu-B1 and Glu-D1 which code for high-molecular-weight subunits of glutenin in hexaploid wheat. Cereal Res Conmun, 11:29-35
Payne PI, 1987. Genetics of wheat storage proteins and the effect of allelic variation on bread-making quality. Ann Rev Plant Physiol, 38:141-153
Plaschke J, Ganal MW, Ridder MS, 1995. Detection of genetic diversity in closely related bread wheat using microsatellite markers. Theor Appl Genet, 91:1001-1007
Redaelli R. 1995. Genetic analysis of low molecular weight subunit fractionated by two-dimensional electrophoresis. J Cereal Sci, 21:5-13
Rder MS, Plaschke J, Knig SU, Brner A, Sorrells ME, Tanksley SD, Ganal MW, 1995. Abundance, variability and chromosomal location of microsatellites in wheat. Mol Gen Genet, 264:327-333
Rder MS, Korzun V, Wendehake K, Plaschke J, Tixier MH, Leroy P, Ganal MW, 1998. A microsatellite map of wheat. Genetics, 149:2007-2023
Rohlf FJ, 2000. NTSYS-pc: numerical taxonomy and multivariate analysis system, version 2.1. Exeter Software: Setauket, NY
Sasanuma T, Chabane K, Takashi R, Valkoun EJ, 2002. Genetic diversity of wheat wild relatives in the Near East detected by AFLP. Euphytica, 128(1):9-17
Schoen, DJ, Brown AHD, 1993. Conservation if allelic richness in wild crop relatives is aided by assessment of genetic markers. Proc NatlAcad Sci, 90:10623-10627
Schoen, DJ, Brown AHD, 1995. Maximizing genetic diversity in core collections of wild relatives of crop species, in: Hodgkin T, Brown AHD, Hintum Th JL van and Morales EAV (eds.) Core Collections of Plant Genetic Resources. International Plant Genetic Resources Institute, Italy, 55-76
Scippa G, Polignano GB, Uggenti P, 2002. Diversity analysis and core collection formation in Bad faba bean germplasm. Plant Genetic Resources Newsletter, 125:33-38
Sharp PJ, Kreis, Shewry PR, Gale MD, 1988. Location of β-amylase sequence in wheat and its relatives. TheorAppl Genet, 75:289-290
Shewry PR, Halford NG, Tatham AS, 1992. High molecular weight subunits of wheat
glutenin. J Cereal Sci, 15:105-120
Skinner DZ, Bauchan GR, Auricht G, Hughes S, 1999. A method for the efficient management and utilization of large germplasm collections. Crop Sci, 39:1237-1242
Skroch PW, Nienhuis J, Beebe S, Tohme J, Pedraza, 1998. Comparison of Mexican common bean (Phaseolus vulgaris L) core and reserve germplasm collections. Crop Sci, 38:488-496
Tohme J, Beebe S, Iglesias C, 1999. Molecular characterization of the CIAT bean and cassava core collections. Core collections for today and tomorrow, International Plant Genetic Resources Institute, Italy, 28-36
Trethowan RW, Pena RJ, Ginkel GV, 2001. The effect of indirect test for grain quality on the grain yield and industrial quality of bread wheat. Plant breeding, 120:509-512
Ude G, Pillay M, Ogundiwin E, Tenkouano A, 2003. Genetic diversity in an African plantain core collection using AFLP and RAPD markers. Theor Appl Genet, 107:248-255
Upadhyaya HD, Ortiz R, Bramel PJ, Singh S, 2003. Development of a groundnut core collection using taxonomical, geographical and morphological descriptors. Genet Resour Crop Evol, 50:139-148
Vaccino P, Metakovsky EV, 1995. RFLP patterns of gliadin alleles in Triticum aestivum L: implications for analysis of the organization and evolution of complex loci. Theor Appl Genet, 90:173-181
Wang L, Ma J, Zhou R, Wang X, Jia J, 2002. Molecular tagging of the yellow rust gene Yr10 in common wheat, P.I. 178383 (Triticum aestivum L.). Euphytica, 124:71-73
Ward RW, Yang Z, Kim HS, Yen C, 1998. Comparative analyses of RFLP diversity in landraces of Triticum aestivum and collection of T. tauschii from China and Southern Asia. TheorAppl Genet, 96:312-318
Wilson Eo, 1985.The biological diversity crisis. Bioscience, 35:,700-706
Yaklich RW, Helm RM, Cockrell G, Herman EM, 1999. Analysis of the Distribution of the Major Soybean Seed Allergens in a Core Collection of Glycine max Accessions. Crop Sci.39:1444-1447
Yan Y, Jovanovic B, Prodanovic S, 1994. Application of electrophoresis for gliadins characterization and varietal identification in wheat. J. Sci Agric Res, 55,93-105
Yonezawa K, Nomura T, Morishima H, 1995. Sampling strategies for use in stratified germplasm collections. In Hodgkin T, Brown AHD, Hintum Th JL van and Morales EAV (eds.) Core Collections of Plant Genetic Resources, International Plant Genetic Resources Institute, Italy, 35-42.
Zeller F J, Hsam SLK, 1996. Chromosomal location of a gene suppressing powdery mildew resistance genes Pm8 and Prn17 in common whent (Triticum aestivum L, em. Thell). TheorAppl Genet, 38-40
Zhang X, Zhao Y, Cheng Y, Feng X, Guo Q, Zhou M, Toby Hodgkin, 2000. Establishment of sesame germplasm core collection in China. Genet Resour Crop Evol, 47:273-279
Zhang X, Li C, Wang L, Wang H, You G & Dong Y, 2002. An estimation of the minimum number of SSR alleles needed to reveal genetic relationships in wheat varieties Ⅰ, Information from large-scale planted varieties and cornerstone breeding parents in Chinese wheat improvement and production. TheorAppl Genet, 106:112-117