玉米骨干自交系遗传多样性分析及茎腐病抗性鉴定

Analysis of genetic diversity and identification of stem rot resistance in maize backbone inbred lines

【目的】提高玉米骨干自交系在杂交亲本中的利用效率。【方法】采用SSR分子标记技术、聚类分析方法和茎腐病田间接种方式,对43份玉米骨干自交系和11份参照系进行遗传多样性分析和茎腐病抗性鉴定。【结果】采用通用40对SSR引物在43份玉米骨干自交系中共检测出242个等位基因变异,平均每对引物检测出6.05个等位基因,平均多态性信息含量为0.61。UPGMA聚类分析结果表明,43份骨干自交系和11份参照系被划分为7个杂种优势群,其中,M17Y130、MU6、M18N41、M17Y334、M85Z、MU7、M17Y340单独成群,暂定为M群。对43份骨干自交系进行遗传多样性分析的同时进行茎腐病(禾谷镰孢菌)田间抗性鉴定,其中37份骨干自交系表现为抗病,主要来源于旅大红骨群、国外Reid群和P群,占86.05%;黄改群、国内Reid群、兰卡斯特群和M群抗病性表现不同。【结论】从分子水平上将43份玉米骨干自交系划分为旅大红骨群体、黄改群体、P群体、国外Reid系、兰卡斯特群体、国内Reid系和M群7个杂种优势群;对茎腐病表现为抗病的骨干自交系主要来源于旅大红骨群、国外Reid群和P群。玉米骨干自交系的使用应结合抗病性进行利用分析。

【Objective】To improve the utilization efficiency of maize backbone inbred lines in hybrid parents.【Methods】Genetic diversity analysis and stem rot resistance identification of 43 maize backbone inbred lines and 11 reference lines were carried out by SSR molecular markers,cluster analysis and field inoculation methods.【Results】A total of 242 alleles were detected in 43 maize backbone inbred lines using 40 pairs of universal SSR primers,with an average of 6.05 alleles per pair of primers and an average of 0.61 polymorphism information.UPGMA cluster analysis showed that 43 backbone inbred lines and 11 reference lines were divided into 7 heterophytic groups,among which M17Y130,MU6,M18N41,M17Y334,M85Z,MU7 and M17Y340 were isolated and tentatively classified as M group.The genetic diversity of 43 backbone inbred lines was analyzed and the field resistance of stem rot(Fusarium graminis)was identified.Among them,37 backbone inbred lines were resistant to stem rot,mainly from Lüda red bone group,Foreign Reid group and P group,accounting for 86.05%.The resistance of Huanggai group,Domestic Reid group,Lancaster group and M group was different.【Conclusion】At the molecular level,43 maize backbone inbred lines were divided into 7 heterosis groups,named Lüda red bone population,Huanggai population,P population,Foreign Reid line,Lancaster population,Domestic Reid line and M group.The backbone inbred lines resistant to stem rot were mainly derived from Lüda red bone group,Foreign Reid group and P group.Maize backbone inbred lines should be used by combined with disease resistance analyzing.