摘要： 生物碱是烟草的重要化学成分。为明确烟草生物碱的遗传结构，发掘控制相关性状的主效位点，以烟草品种Y3、K326为亲本，构建大小为271的重组自交系群体。分别于2018、2019和2020年在云南省昆明市石林、玉溪市研和种植群体材料，检测总植物碱(TPA)、烟碱(NIC)、降烟碱(NOR)、假木贼碱(ANAB)和新烟草碱(ANAT)5种生物碱表型。对群体进行基因组测序，构建包含46,129个标记的遗传连锁图谱。利用基于混合线性模型的QTL定位方法及软件QTLNetwork 2.0，进行QTL定位分析。共定位15个具有显著加性效应的QTL，加性效应对表型贡献率为0.58%~11.57%。其中4个主效QTL即控制总植物碱的qTPA14、烟碱的qNIC14、假木贼碱的qANAB14和新烟草碱的qANAT14，均可以解释相应性状10%以上的表型变异，且均位于14号连锁群上。6个QTL具有显著的加性与环境互作效应，对表型贡献率为0.80%~1.81%。5对QTL具有显著加性-加性上位性效应，对表型的贡献率为0.15%~2.31%。2对QTL具有显著的上位性与环境互作效应，对表型的贡献率为0.81%~1.16%。研究结果为进一步分离候选基因、解析遗传机理和促进烟草生物碱性状分子改良奠定了基础。

关键词： 烟草,  重组自交系,  生物碱,  复杂性状,  基因与环境互作 

Abstract: Alkaloids are important chemical components in tobacco. In order to understand the genetic architecture of alkaloids in tobacco and identify major effect loci controlling alkaloids related traits, QTL mapping on tobacco alkaloids was performed. A set of 271 recombinant inbred lines (RIL) were constructed with Y3 and K326 as the parents. The RIL population was planted in Yanhe, Yuxi, Yunnan Province and Shilin, Kunming, Yunnan Province in 2018, 2019, and 2020, respectively. Five alkaloid phenotypes including total plant alkali (TPA), nicotine (NIC), nornicotine (NOR), anabasine (ANAB), and anatabine (ANAT) were measured. A linkage map of 46,129 markers was constructed by genome sequencing of the population. QTL mapping was performed by the software QTLNetwork 2.0 which was developed based on the mixed linear model. A total of 15 QTLs with significant additive effects were identified. The contribution rate of additive effect to the corresponding phenotypes varied from 0.58% to 11.57%. Four major QTLs, qTPA14 for total plant alkali, qNIC14 for nicotine, qANAB14 for anabasine, and qANAT14 for anatabine, accounted for more than 10% of phenotypic variation of the corresponding traits, which were located in linkage group 14. Six QTLs with significant additive-by-environment interaction effects were detected, their additive-by-environment interaction effects explained the phenotypic variation of 0.80%–1.81%. Five pairs of QTLs with significant additive-by-additive epistasis effects were detected, accounting for phenotypic variation from 0.15% to 2.31%, while two pairs of QTLs were detected with significant epistasis-by-environment interaction effects, which explaining the proportion of phenotypic variation from 0.81% to 1.16%. The results pave a foundation for further isolation of candidate genes, the dissection of genetic mechanism, and the molecular improvement of tobacco alkaloid traits.

Key words: tobacco,  the recombinant inbred line,  alkaloids,  complex traits,  gene by environment interaction 

收稿日期: 2023-03-09

基金资助: 本研究由中国烟草总公司[110202101002(JY-02), 110202101038 (JY-15)]和云南省烟草公司项目(2021530000241013, 2022530000241009)资助。