黄瓜RIL群体瓜长和把长的QTL定位分析

Quantitative Trait Loci Associated with Fruit Length and Stalk Length in Cucumber Using RIL Population

以黄瓜野生变种‘PI183967’（Cucumis sativus L.hardwickii）和新泰密刺选系‘931’为亲本,通过单粒传法获得包含160个株系的F9代重组自交系群体（RIL）.结合分子遗传图谱和不同年份（2012年春、秋季和2013年春、秋季）的表型调查数据,利用MapQTL4.0软件进行黄瓜瓜长和把长的QTL定位.结果显示：（1）共检测到8个与瓜长和把长相关的QTLs,分布在染色体3、4、5、6、7上,LOD值在2.78~10.24之间,可解释7.4％~32.7％的表型变异率,贡献率≥10.0％的QTL位点4个,占QTLs总数的1/2,在春秋两季重复检测出的QTL位点有4个.（2）检测到4个与瓜长相关的QTLs位点Fl3.1、Fl4.1、Fl5.1、Fl6.1,4个与把长相关的QTLs位点Fsl3.1、Fs玛.2、Fsl5.1、Fsl6.1.（3）Fl6.1和Fsl6.1在2012、2013年春秋季中均可检测到,位于第6号染色体的109.2 cM处,标记SSR17591~C80之间;Fl6.1在4次中的贡献率在13.8％~32.7％之间,Fsl6.1在4次中贡献率为12.1％~24.1％;（4）Fl3.1和Fsl3.2位于第6号染色体标记SSR16152~SSR07706之间,其中Fl3.1在2012年秋季和2013年春秋两季中均可检测到,贡献率总共为25.1％,Fsl3.2仅在2012年秋季中检测到,解释8.8％的表型变异率.研究表明,第6号染色体上标记SSR17591~C80和第3号染色体上的SSR16152~SSR07706等2个区域聚集了控制瓜长和把长的主效QTL位点,这2个区域应作为今后研究的重点.

A 160 recombinant inbred lines（RILs） were derived from a cross between ‘PI183967’and a cultivated Northern Chinese inbred line‘ 931’.The constructed genetic map and phenotypic data in different seasons were used to identify the quantitative trait loci（QTL） associated with fruit length（Fl） and stalk length（Fsl）.Results showed that：（1） 8 QTLs related to Fl and Fsl were located on Chr.3,4,5,6 and 7 with LOD between 2.78 and 10.24,which explained 7.4％-32.7％ of the phenotypic variation.Of those QTLs,there were 4 QTLs which explained over 10％ phenotypic variation and 4 QTLs which could be detected in different seasons.（2）4 QTLs（Fl3.1,Fl4.1,Fl5.1,Fl6.1） associated with fruit length and 4 QTLs（Fsl3.1,Fsl 5.1,Fsl6.1,Fsl7.1） associated with stalk length.（3）Fl6.1 and Fsl6.1 could be detected in 2012,2013 spring and autumn which located on 109.2 cM of chromosome 6 between SSR17591 and C80.The range of phenotypic variation of Fl6.1 was 13.8％-32.7％ and Fsl6.1 was 12.1 ％-24.1％.（4）Fl3.1 and Fsl3.2 were located between SSR16152 and SSR07706.The QTL of Fl3.1 was detected in 2012 autumn and 2013 spring and autumn,explaining 25.1 ％ of the phenotypic variation in all,while Fsl3.2 was just detected in 2012 autumn,which explained 8.8％ of the phenotypic variation.Therefore,the region of SSR17591-C80 on Chr.6 and SSR16152-SSR07706 on Chr.3 were major regions which controlled fruit length and stalk length.The two regions should been put key location for the future research on fruit length and stalk length.