花生突变体创制与品质性状分析

Creation and Quality Analysis of Peanut Mutants

栽培种花生遗传基础相对狭窄,常规育种难以培育出突破性新产品,利用诱变手段创制突变体材料是作物种质改良和理论研究的重要途径。本研究以鲁花6号、花育19号、花育20号、花育23号、花育32号、花育33号、四粒红、龙花生8个花生品种(种质)为材料,利用EMS诱变、60Co-γ射线辐照或快中子辐照分别对种子进行处理,获得了一个突变体库。利用近红外法检测突变体主要品质性状,发现诱变可提高突变体的油酸含量和油亚比值,油亚比变异系数较大。相关性分析发现,油酸含量与棕榈酸含量和油亚比间分别呈极显著负相关和正相关。各品质性状对油亚比的影响顺序:油酸含量(1.522)>棕榈酸含量(0.387)>含油量(-0.271)>蛋白质含量(-0.273)>蔗糖含量(-0.698)。采用竞争性等位基因特异性PCR(KASP)检测发现,154份花育19号高油酸突变体FAD2B基因的442bp位点插入了一个“A”,导致高油酸突变性状的产生。突变体油酸、亚油酸变幅分别为66.46%~80.30%和1.29%~13.34%,油亚比变幅4.98~62.31。本研究丰富了花生种质资源,并为花生遗传改良和功能基因鉴定提供了丰富的试验材料及理论依据。

There is relatively narrow genetic background of cultivated peanut varieties,so that it is difficult to breed breakthrough new varieties via conventional breeding strategies.The use of mutagenesis to create mutant materials is an important way to improve crop germplasm and lay a foundation for theoretical research.In this study,eight cultivated peanut varieties(germplasms),Luhua6,Huayu19,Huayu20,Huayu23,Huayu32,Huayu33,Silihong and Dragon peanut,were induced by ethymethane sulfonate(EMS),60Co-γor fast neutron radiation,and a mutant population was gained.The main quality traits were observed and measured,and statistical analysis was performed.The results indicated that mutagenesis might increase the oleic acid content in mutants.The coefficient of variation of oleic/linoleic acid ratio(O/L)in most varieties(germplasms)was obvious.The oleic acid content showed a very significant negative correlation with the palmitic acid content,and a very significant positive correlation with O/L ratio.Principal component analysis showed that quality traits were mainly affected by two principal components.Path analysis indicated that the order of the influence of quality traits on O/L ratio was:oleic acid content(1.522)>palmitic acid content(0.387)>oil content(-0.271)>protein content(-0.273)>sucrose content(-0.698).Detection of AhFAD2 genes of 154 peanut high oleic mutants using KASP method found that an insertion of A at the 442bp site of AhFAD2B appeared in these materials,which may increase the oleic acid in peanuts.For these mutants,the oleic acid content was between 66.46%~80.30%.The linoleic acid content was between 1.29%~13.34%.The O/L ratio was between 4.98~62.31.These studies provided a population of germplasms and theoretical basis for peanut genetic improvement and functional gene identification.