离体筛选花生抗逆突变体及其后代特征特性研究

In vitro SELECTION FOR STRESS-RESISTANT MUTANTS AND SURVEY ON OFFSPRING CHARACTERISTICS OF PEANUT

在课题组前期研究确立的花生体胚诱导及高频率植株再生体系和确立的适宜平阳霉素(PYM)诱变浓度基础上,进行花生离体诱变及定向筛选抗逆突变体研究。以花生品种花育20号成熟种子胚小叶为诱变材料,在含3mg/L PYM的诱导培养基上培养4周进行诱变处理。以羟脯氨酸(HYP)作为筛选压力添加于培养基中,确定体胚萌发阶段培养基中添加4mg/L HYP,以及体胚萌发后添加8mg/L HYP为适宜浓度的筛选方法。2011年将获得的HYP耐性苗经嫁接移栽田间,成熟后13株耐性嫁接苗获得种子。2012年将13个单株的部分种子分别播种于田间,生长发育阶段观察发现,12个耐性植株后代在株高、茎枝颜色、株型、开花习性等方面与诱变亲本不同,明显表现出变异,并且大部分植株后代性状发生分离。13个耐性单株中的7个单株收获的其他种子分别播种于塑料大棚,苗期进行干旱处理后,大部分植株生长正常,而诱变亲本的生长明显受到抑制;取干旱处理后的叶片测定POD活性和SOD活性,结果显示,这7个耐性单株中的5个单株后代SOD活性高于亲本,这5个单株后代中的4个POD活性也高于亲本。

Previous studies in our lab had established high frequency of plant regeneration system via somatic embryogenesis and determination of the optimum mutation concentration of pingyangmycin（PYM）,in vitro mutagenesis and directed screening for stress-resistant mutants of peanut were carried out in this study.The embryonic leaflets of peanut cv.Huayu 20 were cultured on induction medium supplemented with 3mg/L PYM for 4 weeks to induce mutation.Hydroxyproline（HYP） was added to medium to provide selection pressure;the concentration was 4mg/L for somatic embryo germination and 8mg/L for plantlet formation.Regenerated mutant plants were transplanted to the field after graft and acclimation,13 of them produced pods.The seeds of these 13 strains were sown in the field,12 out of them exhibited different plant type compared with their wild type parent during seedling stage and growth stages,and most of them showed remarkable segregation of characters.The rest seeds from 7 of 13 strains mentioned above were sown in the green house,and were treated with drought stress.Most of the plants grew normally,while the wild type parent showed growth retardation.POD and SOD activity were determined using leaves subjected to drought stress as material.The results showed that the SOD values of 5 out of 7 lines were higher than that of the parent;the POD values of these lines also higher than that of the parent expect No.42.