摘要
铅(Pb2+)是现存环境最大量的有毒重金属污染元素,在我国特别是西南地区种植的玉米受重金属Pb2+污染日益严重,已严重影响到食物安全。文章利用玉米籽粒Pb2+低富集自交系178和籽粒Pb2+高富集自交系9782杂交衍生的重组自交系群体为作图群体,利用165对SSR多态性标记,构建了总长度为1499.85 cM、标记间平均距离为9.07 cM的分子遗传图谱,对玉米籽粒Pb2+含量性状进行了QTL定位分析,以期为选育籽粒低富集Pb2+的玉米新品种提供参考。结果表明,在Pb2+浓度为333.32 mg/kg胁迫下,共检测到2个与籽粒Pb2+含量相关的QTL,分别位于玉米第1、第4号染色体,其中qPC1位于标记区间umc1661~phi002h之间,表型贡献率为11.13%,加性效应为0.062;qPC4位于umc1117~nc005之间,表型贡献率为5.55%,加性效应为-0.044。性状相关分析结果表明,籽粒中Pb2+含量与穗长、穗粗、行粒数、穗重和百粒重等产量性状间均未达到显著水平,表明选育玉米籽粒Pb2+低富集的新自交系或杂交种不一定会影响到产量性状,而且籽粒Pb2+含量是一个相对独立的遗传性状。
Lead （Pb2＋） is one of the most abundant heavy-metal elements in the environment. Pb2＋ pollution has become increasingly serious in maize planting areas, especially in the southwest of China, which even threatens food security. In the present study, a RILpopulation derived from 178 （an inbred line with low accumulation of Pb2＋ in the kernels） and 9782 （a pb2＋hyperaccumulator in the kernels） was used for QTL mapping. A molecular genetic map with the length of 1499.85 cM and an average inter-marker distance of 9.07 cM was constructed with 165 pairs of SSR markers. QTLs controlling Pb2＋ content in maize kernels were then analyzed to provide the basis for breeding elite maize varieties with low pb2~in the kernels. Two QTLs, qPC1 and qPC4, related to Pb2＋ content in maize kernelswere identified on chromosome 1 and 4, respectively, qPC1 was located between markers umc1661 and phi002, ac- counting for 11.13% of phenotypic variance with an additive effect value of 0.062. While qPC4 was located between markers umclll7 and nc005, explaining 5.55% of the phenotypic variance with an additive effect value of-0.044. However, there was no significant correlation observed between Pb2＋ content in the kernels and any of yield-related traits including ear length, ear diameter, kernel row number and weight of per-hundred kernels, indicating that yield-related traits would not be changed in the process of low-pb2＋maize breeding. This suggested that the pb2＋content in maize kernel under pb2＋stress was an independent genetic trait.
出处
《遗传》
CAS
CSCD
北大核心
2014年第8期821-826,共6页
Hereditas（Beijing)
基金
国家自然科学基金项目(编号:31171567)资助
