【作者】 刘静；

【导师】 杨学举； 安浩军；

【作者基本信息】 河北农业大学 ， 农业硕士（专业学位）， 2022， 硕士

【摘要】 小麦(Triticum aestivum L.)是世界性食粮,在我国粮食安全中举足轻重。目前小麦育种面临的“卡脖子”问题是种质资源匮乏,技术手段滞后。利用人工诱变创造突变体,构建突变体库,可有效地培育小麦优异新种质和新品种,加快解析相关性状的基因功能。本研究以完成基因组测序的优良小麦品种“矮抗58”为供试材料,利用甲基磺酸乙酯(EMS)设置不同诱变组合(浓度+时间),按照种子萌发致死率50%的标准筛选最佳诱变组合,以之处理“矮抗58”种子。经自交、稳定、鉴定、筛选等环节,创制突变体材料,构建突变体库,对各类突变类型进行性状鉴定,筛选具有重要价值的突变体。主要研究结果如下:1.确定了最佳诱变处理条件。通过6种EMS浓度(0.00%、0.60%、0.80%、1.00%、1.20%、1.40%)和5种时间(6 h、8 h、10 h、12 h、14 h)设置30个处理,诱变小麦品种“矮抗58”种子。按照种子萌发致死率50%的标准,确定最佳处理组合为:EMS浓度1.20%+处理时间10 h。2.构建了“矮抗58”突变体库。诱变获得7156个M1单株,选到1000个变异类型,变异中选率为13.98%。经M1、M2自交和选择,获得658个性状比较稳定的M3突变体株系,组成突变体库。3.突变体库变异类型丰富。突变类型包括高秆、矮秆、蜡质、寡分蘖等与茎秆相关的变异,黄叶、畸形叶、大叶、小叶等与叶部相关的变异,长穗、短穗、密集小穗、不同穗型等与穗相关的变异,长芒、短芒、顶芒、黑芒等与芒相关的变异,大粒、小粒、皱粒等与籽粒相关的变异,还发现了株型、育性、抗病性、耐寒性等突变体材料。4.鉴定了各类突变体特性。高秆突变体16份,占中选突变体总数的2.43%,变异幅度82.3 cm-100.0 cm;矮秆突变体18份,占比2.74%,变异幅度30.7 cm-36.7 cm;蜡质突变体28份,占比4.26%;分蘖减少突变体17份,占比2.58%,分蘖数变异幅度1个-6个;旗叶较长突变体7份,占比1.06%,变异幅度28.3 cm-32.2 cm;旗叶较短突变体4份,占比0.61%,变异幅度5.5 cm-9.8 cm;旗叶较宽突变体11份,占比1.67%,变异幅度2.5 cm-2.9 cm;叶片黄化突变体8份,占比1.22%;条纹叶变体10份,占比1.52%;螺旋叶突变体15份,占比2.30%;椭圆叶突变体7份,占比1.06%;叶基部收缩突变体22份,占比3.34%;长穗突变体11份,占比1.67%,变异幅度12.0 cm-13.7 cm;短穗突变体6份,占比0.91%,变异幅度5.2 cm-5.9 cm;小穗数较少突变体10份,占比1.52%,变异幅度13个-15个;小穗数较多突变体8份,占比1.22%,变异幅度23个-35个;穗型突变体27份,占比4.10%;长芒突变体12份,占比1.82%,变异幅度8.0 cm-9.8 cm;短芒突变体11份,占比1.67%,变异幅度0.0 cm-2.4 cm;黑芒突变体4份,占比0.61%;株型突变体18份,占比2.74%,变异株型为松散型和簇生型;籽粒皱缩突变体9份,占比13.7%;粒重较低突变体5份,占比0.76%,变异幅度22.82 g-29.73g;早衰突变体1份,早熟突变体1份,晚熟突变体4份;耐寒等级为1级突变体22份,占比3.34%;白粉病抗性1级突变体117份,占比17.78%;育性降低突变体29份,占比4.41%;苗期叶片黄化突变体28份,占比4.26%。突变体材料中叶部突变最多共109份,占比16.57;株型突变体最少共18份,占比2.74%5.筛选出有价值的突变体。发现的大穗突变体、矮秆突变体、粒重增加突变体、早熟突变体、短宽叶突变体、密穗突变体、大粒突变体等在种质资源创新与小麦品种改良方面有重要价值。发现的黄化突变体、早衰突变体、不育突变体、畸形突变体、粒重降低突变体等为基因功能解析和相关性状的遗传机制研究提供了基础材料。“矮抗58”突变体库的构建为小麦育种创制了新种质,为基因功能解析提供了新材料。更多还原

【Abstract】 Wheat(Triticum aestivum L.)is a worldwide food and plays an important role in China’s food security.At present,the "stuck neck" problem faced by wheat breeding is the lack of germplasm resources and the lagging technical means.The use of artificial mutagenesis to create mutants and construct a mutant library can effectively cultivate excellent new germplasm and new varieties of wheat,and accelerate the analysis of gene functions of related traits.In this study,the excellent wheat variety "Aikang-58",which have been completed genome sequencing,was used as the experimental material,and ethyl methanesulfonate(EMS)was used to set different mutagenesis combinations(concentration+time),according to the standard of 50%seed germination lethality Screen the best mutagenesis combination to soak the seeds of "Aikang-58".After selfing,stabilization,identification,screening,etc.,mutant materials are created,mutant libraries are constructed,traits of various types of mutations are identified,and mutants of important value are screened.The main findings are as follows:1.The best mutagenesis treatment conditions have been determined.Mutated the seeds of wheat variety "Aikang-58" by setting 30 treatments through 6 EMS concentrations(0.00%,0.60%,0.80%,1.00%,1.20%,1.40%)and 5 times(6 h,8 h,10 h,12 h,14 h).Change the seeds of wheat variety "Aikang-58".According to the 50%standard of seed germination lethality,the best treatment combination was determined as EMS concentration 1.20%+treatment time 10 h.2.A mutant library of "Aikang-58"has been constructed.7156 M1 individual plants were obtained by mutagenesis,and 1000 mutation types were selected.The selection rate among the mutations was 13.98%.After selfing and selection by M1 and M2,658 M3 mutant lines with relatively stable traits were obtained,which constituted a mutant library.3.The mutant library mutation types have been riched.The mutation types include tall,dwarf,waxy,oligo tiller and other stalk-related mutations,yellow leaves,deformed leaves,large leaves,small leaves,and other leaf-related mutations,long spikes,short spike,dense spikelets,Variations related to ears such as different ear types,variations related to awns such as long awn,short awn,top awn,and black awn,and the variation related to grain such as large,small and wrinkled kernels,mutant material such as strain type,fertility,disease resistance,and cold resistance were also been discovered.4.The characteristics of various mutants have been identified.16 high-stalk mutants,accounting for 2.43%of the total number of selected mutants,with a variation range of 82.3 cm-100.0 cm;18 short-stem mutants,accounting for 2.74%,with a variation range of 30.7 cm-36.7 cm;28 were waxy mutants,accounting for 4.26%;17 mutants with reduced tillers,accounting for 2.58%,variation range of tiller number from 1 to 6;7 mutants with longer flag leaves,accounting for 1.06%,variation range of 28.3 cm-32.2 cm;flag leaves more 4 short mutants,accounting for 0.61%,with a variation range of 5.5 cm-9.8 cm;11 mutants with a wider flag leaf,accounting for 1.67%,with a variation range of 2.5 cm-2.9 cm;8 leaf yellowing mutants,accounting for 1.22%;10 striped leaf variants,accounting for 1.52%;15 spiral leaf mutants,accounting for 2.30%;There were 7 elliptic leaf mutants,accounting for 1.06%;22 leaf base contraction mutants,accounting for 3.34%;11 long panicle mutants,accounting for 1.67%,with a range of 12.0 cm-13.7 cm;short panicle mutants 6 The proportion is 0.91%,and the variation range is 5.2 cm-5.9 cm;there are 10 mutants with less spikelets,accounting for 1.52%,and the variation range is 13-15;8 mutants with more spikelets,accounting for the proportion 1.22%,with a variation range of 23-35;27 ear-type mutants,accounting for 4.10%;12 long-mang mutants,accounting for 1.82%,with a variation range of 8.0 cm-9.8 cm;11 short-mang mutants,Accounted for 1.67%,with a variation range of 0.0 cm-2.4 cm;4 black awn mutants,accounting for 0.61%;18 plant-type mutants,accounting for 2.74%,the variants were loose and clustered;grains shrunk 9 mutants,accounting for 13.7%;5 low-grain weight mutants,accounting for 0.76%,with a variation range of 22.82 g-29.73g;1 premature aging mutant,1 early maturity mutant,and 4 late maturity mutants;There were 22 mutants with grade 1 cold tolerance,accounting for 3.34%;117 mutants with grade 1 powdery mildew resistance,accounting for 17.78%;29 mutants with reduced fertility,accounting for 4.41%;leaf yellowing mutation at seedling stage 28 copies of the body,accounting for 4.26%.There are a total of 109 mutations in the middle of the mutant material,accounting for 16.57;the plant-type mutant has a minimum of 18 mutations,accounting for 2.74%.5.Valuable mutants have been screened out.The discovered mutants such as large spike mutants,dwarf mutants,increased grain weight mutants,early maturity mutants,short and wide leaf mutants,dense spike mutants,large grain mutants,etc.,are have an important effect in germplasm resource innovation and wheat variety improvement.The discovered mutants such as yellowing mutants,premature aging mutants,sterile mutants,deformed mutants,and reduced grain weight mutants provided basic materials for the analysis of gene function and the study of genetic mechanisms of related traits.The construction of the "Aikang-58" mutant library created new germplasm for wheat breeding and provided new materials for gene function analysis.更多还原