摘要：

为了探索花生高油育种新途径,建立一种直接育成高油花生种质的新方法,采用离体诱变育种技术进行花生高油新种质创制。以吉花9号胚小叶为诱变试材,吉花9号和吉花54为对照试材,以博来霉素作为诱变剂。胚小叶消毒后放置在梯度诱变培养基中,筛选博来霉素诱变半致死浓度,体胚萌发成苗后以无菌花生苗作为砧木采用插接法进行无菌嫁接,嫁接成苗后移栽至田间。对2个已知调控花生脂肪合成基因WRI1进行生物信息学分析,并通过籽粒中WRI1基因表达和诱变植株粗脂肪含量相关性进行试验可行性验证。当博来霉素质量浓度在3 mg/L时,诱变效果最佳。吉花9号突变体IM13-3的粗脂肪含量高于吉花9号(CK₁,试材品种对照)和吉花54(CK₂,高油品种对照)。2个WRI1基因WRI1X2和WRI1X1分别编码366,357个氨基酸,都是不稳定亲水性蛋白。在籽粒中WRI1基因表达量与粗脂肪含量呈显著正相关。率先采用博来霉素作为花生离体诱变诱变剂,通过此离体诱变方法获得吉花9号高油突变体IM13-3,粗脂肪含量为56.64%。测定了高油突变体WRI1基因表达量,与对照品种存在显著差异。证明花生离体诱变方法育种方法可行性。

关键词: 高油花生, 离体诱变, 博来霉素, WRI1, 表达分析

Abstract:

In order to explore new approaches for high-oil peanut breeding and establish a new method for directly developing high-oil peanut germplasm,this study employed in vitro mutagenesis breeding technology to create new high-oil peanut germplasm.Jihua 9 embryo leaflet was used as mutagenic test materials,Jihua 9 and Jihua 54 were used as control test materials,and bleomycin was used as mutagenic agent.The ovules were sterilized and placed in gradient mutagenesis medium and screened for semi-lethal concentrations of bleomycin.After somatic embryos germinated into seedlings,sterile peanut seedlings were used as rootstocks,and transplanted to the field.Bioinformatics analysis of two known regulated peanut fat synthesis genes WRI1 and experimental feasibility validation by the correlation of WRI1 gene expression in grain and crude fat content of mutagenic plants were conducted.The results were best when the bleomycin was 3 mg/L.The crude fat content of IM13-3 was higher than that of Jihua 9(CK₁,test variety control)and Jihua 54(CK₂,high oil variety control).Two WRI1 genes,WRI1X2 and WRI1X1,encoding 366 and 357 amino acids,respectively,were both unstable hydrophilic proteins. WRI1 gene expression and crude fat content were significantly positively associated in grain.Bleomycin was first used as a peanut vitro mutagenesis agent,and IM13-3 was obtained with a crude fat content of 56.64%.It further proves the authenticity of Jihua 9 high oil mutant and the feasibility of peanut in vitro mutagenesis method. The gene expression level of the high-oil mutant WRI1 was determined and was significantly different from the control varieties. Demonstrate the feasibility of breeding methods for in vitro mutagenesis of peanut.

Key words: High-oil peanut, Mutagenesis in vitro, Bleomycin, WRI1, Expression analysis