烤烟生育期相关性状的初步遗传分析

为了初步掌握烤烟生育期相关性状的遗传机理，本研究利用了由开花相对稍早的品种K326和迟花品种兴烟1号杂交所得的F1植株经过组织培养和染色体加倍技术获得的双单倍体（doubled haploid, DH）群体为作图群体，以AFLP和SSR分子标记为主构建了包含23个连锁群、160个标记的烤烟遗传连锁图谱，其中包括23个AFLP标记、1个SRAP标记和136个SSR标记，图谱总长为1814.1 cM。利用复合区间作图法对烟草生育期相关性状开花时间和有效叶数进行了初步的遗传分析，结果表明，共检测到3个主效QTL位点与生育期性状相关，其中2个位点（df1和df2）与开花时间相关，分别位于第1和第11连锁群，表型变异贡献率分别为24.5%和17.3%；第3个位点与有效叶数（npl）相关，分布在第3连锁群上，表型变异贡献率为18.6%，该结果为后续利用高通量分析手段对烟草生育期性状进行精细定位奠定了基础。 

Preliminary genetic analysis of growth period traits of flue-cured tobacco

In order to understand the genetic control of growth period traits including days to flower (dtf) and number of productive leaves (npl) of flue-cured tobacco, a genetic linkage map was built based on one DH population derived from one F1 crossed by early-flowering cultivar K326 and late-flowering cultivar Xingyan No.1.This map was composed of 23 AFLP, one SRAP and 136 SSR molecular markers assembled into 23 linkage groups (LG1 – LG23) with a total genetic distance of 1814.1 cM. Composite interval mapping (CIM) was used to detect QTLs involved in dtf and npl of flue-cured tobacco. The result showed that a total of three main-effect QTLs for these two traits were detected, of which two (dtf1 in LG1 and dtf2 in LG11) for dtf and one (npl in LG3) for npl. Dtf1 and dtf2 accounted for 24.5% and 17.3% of phenotypic variation of dtf, respectively. Npl accounted for 18.6% of npl variation. This primary conclusion can provide one good reference for further study on fine mapping of growth period traits of tobacco using high-throughput technologies.