opaque 2基因微卫星标记与玉米籽粒赖氨酸含量的关系

Microsatellite Marker of opaque 2 Gene Related to the Lysine Content of Maize

利用opaque 2 (o2 )基因序列内的微卫星标记phi0 5 7、phi112和umc10 6 6检测优质蛋白和普通玉米自交系CA335及黄早四 ,发现phi0 5 7是共显性标记 ,且具有明显的多态性。利用标记phi0 5 7对BC1F1回交群体 [(CA335×黄早四 )×CA335 ]的 2 2 4个单株进行检测 ,两种基因型o2o2和o2O2的分离比为 1∶1 2 4 ,符合孟德尔遗传分离比例。进一步将群体内同一基因型o2O2或o2o2植株上的籽粒混合测定赖氨酸含量 ,发现o2o2基因型玉米籽粒的赖氨酸含量 (0 4 2 8% )显著大于o2O2基因型 (0 334% )。研究表明利用微卫星标记phi0 5 7辅助选择玉米o2o2基因型 ,可以提高优质蛋白玉米的选择效率。

The polymorphism at microsatllite marker loci,phi057,phi112 and umc1066,developed in opaque 2 gene was investigated between the line of quality protein maize CA335 and normal line Huangzao 4. The PCR and electrophoresis results indicated that phi057 was co-dominant marker and showed high polymorphism. By using phi057,the segeragation ratio of two genotypes,o2o2 and o2O2,detected among 224 individuls of [(CA335×Huangzao4)×CA335] BC 1F 1 population was 1∶1.24,which accorded with Mendelian ratio. The kernels of o2o2 and o2O2 derived from the backcross population were harvested and bulked to measure the lysine content. The average lysine content (0.428%) of o2o2 genotypes was significantly higher than that of o2O2 genotyoes (0.344%). It was suggested that the maize materials with high lysine content would be effectively obtained by marker-assisted selection approrach with microsatellite marker phi057.