陆地棉产量、纤维品质相关性状主效QTL和上位性互作分析  

Genetic Analysis of Major QTLs and Epistasis Interaction for Yield and Fiber Quality in Upland Cotton

作　　者：林忠旭[1] 冯常辉[1] 郭小平[1] 张献龙[1] 

机构地区：[1]华中农业大学作物遗传改良国家重点实验室与国家植物基因研究中心(武汉),武汉430070

出　　处：《中国农业科学》2009年第9期3036-3047,共12页Scientia Agricultura Sinica

基　　金：国家高技术研究发展计划("863"计划)项目(2006AA10Z153;20060AA00105)

摘　　要：【目的】为了能够较为全面地了解陆地棉产量和纤维品质相关性状的遗传基础,利用包含471个标记、总长3070.2cM、覆盖棉花基因组65.88%左右的遗传图谱对其进行主效QTL定位和上位性互作分析。【方法】以DH962×冀棉5号的F2:3家系为分析群体,用WinQTLCartV2.5进行复合区间作图定位主效QTL,利用EPISTACY软件对共显性标记进行两位点的上位性互作分析。【结果】共检测到9个与产量相关性状的主效QTL,和5个与纤维品质相关性状的主效QTL,整齐度和比强度在显著LOD阈值下没有检测到相关QTL。共检测到75对互作位点,大多数互作属于非QTL位点与非QTL位点之间的互作,互作类型以加性显性互作和显性加性互作为主。所涉及的性状中,影响衣分和纤维长度的互作位点最多,单株铃数和衣指的最少。在LG1上检测到1个同时控制单株籽棉重、单株皮棉重和籽指主效QTL。在两位点的互作对中也发现了同时影响单株籽棉重、单株皮棉重和马克隆值的互作位点1对,同时影响衣分和纤维长度的互作位点4对。【结论】除了主效QTL外,上位性是陆地棉产量和纤维品质性状的重要遗传基础。主效QTL的效应小和上位性互作将会使得棉花分子标记辅助育种更加困难和复杂。表型相关的性状是由相同的QTL/互作位点所控制,这有助于多个性状的同时选择。【Objective】 The aim of this investigation was to better understand the genetic base of yield and fiber quality traits in upland cotton. Major quantitative trait loci （QTL） associated with yield and fiber quality and epistasis interaction in controlling these traits were mapped using a genetic linkage map which comprised 471 loci, spanned 3 070.2 cM and covered 65.88% of the whole cotton genome. 【Method】 An F2：3 population from DH962 × Jimian5 was used to evaluate yield and fiber quality. Major QTLs were identified by composite interval mapping method on WinQTLCartV2.5. Two-way digenic interactions analysis was conducted using EPISTACY. [ Result] Nine major QTLs were detected for six yield traits and five for fiber quality traits. No QTLs were detected for fiber uniformity ratio and fiber strength under the significant threshold LOD scores. A total of 75 significant digenic interactions were detected, most of them were non-QTL × non-QTL interaction; most of the interaction types were additive × dominance interaction and dominance × additive interaction. Many digenic interactions were detected for lint percentage and fiber length, and only few for boll number and lint index. One common major QTL for SCW, LW and SI was detected on LG1. Common digenic interactions were also found for some correlated traits： one for SCW, LW and MV; four for LP and FL. [Conclusion] Except for major QTLs, epistasis played an important role in the genetic basis of yield and fiber traits in upland cotton. The low effect of major QTLs and the digenic interactions will make it more difficult and more complex for maker-assisted selection in cotton breeding. Correlated traits were controlled by same QTLs/digenic interactions, which will be helpful to select these traits simultaneously.

关 键 词：陆地棉 产量 纤维品质 主效QTL 上位性 

分 类 号：S562[农业科学—作物学]