Characterizing the main and epistatic effects and interactions of germination-related quantitative trait loci of tomato using a backcross inbred line population and near-isogenic lines
Characterizing the main and epistatic effects and interactions of germination-related quantitative trait loci of tomato using a backcross inbred line population and near-isogenic lines
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DOI：
10.1016/j.scienta.2019.109028
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发表时间：
2020-02-05
影响因子：
4.3
通讯作者：
Sugiyama, Nobuo
中科院分区：
文献类型：
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作者：
Nakano, Hajime;Takahata, Ken;Sugiyama, Nobuo
在不利的环境条件下快速发芽和早期建立幼苗是育苗生产的理想性状。在15和25摄氏度下使用回交近交系家族进行发芽速度的数量性状基因座（QTL）分析。测定了最终发芽率（FGP）、达到50%和90% FGP的天数（分别为GT（50）和GT（90））、平均发芽时间（MGT）和发芽时间的协方差。结果表明，在第1-3染色体上存在11个加性发芽相关QTL，在第11 ~ 13染色体上存在11个加性发芽相关QTL。GT（50）、GT（90）和MGT QTL均位于第1-3染色体上，其中gt（50）1、gt（90）1和mgt 1具有正加性效应。在第4染色体上检测到一个上位性QTL，但未检测到具有加性效应的QTL，这与以往的研究结果不一致。为了重新研究1号和4号染色体上的QTL效应，我们构建了1个和3个携带一个被替换染色体片段的近等基因系（NILs），其中在1号和4号染色体上检测到推定的QTL。近等基因实验结果表明，第1染色体上位于TGS 0308和C2_At5g49480标记之间的一个来自SP的染色体片段在15 ℃和25 ℃下分别缩短和延长了发芽时间，这是由于QTL与环境的互作。而第4染色体上SSR 603和TGS 0411标记之间的替换片段对种子萌发没有影响。总之，第1染色体上的QTL是有用的育种品种，能够在低温下发芽。
Rapid germination and early establishment of seedlings under unfavorable environmental conditions are desirable traits for seedling production. Quantitative trait locus (QTL) analysis of germination speed was conducted at 15 and 25 degrees C using a backcross inbred line family. Final germination percentage (FGP), days to 50 % and 90 % of FGP (GT(50) and GT(90), respectively), mean germination time (MGT), and covariance of germination time were determined. The results indicated 11 additive germination-related QTLs on chromosomes 1-3, and 11. GT(50), GT(90), and MGT QTLs detected on chromosomes 1-3 were co-located, of which, gt(50)1, gt(90)1, and mgt1 had positive additive effects. A single epistatic QTL was detected, but no QTL with additive effect was found on chromosome 4 in the present study, which was not consistent with the results of previous studies. To reexamine the effect of QTLs on chromosomes 1 and 4, we constructed one and three near-isogenic lines (NILs) carrying a substituted chromosome segment from Solanum pimpinellifolium (SP) in which putative QTLs were detected on chromosomes 1 and 4. NIL experiment results indicated that a chromosomal segment from SP between TGS0308 and C2_At5g49480 markers on chromosome 1 shortened and prolonged germination time at 15 degrees C and 25 degrees C, respectively, due to QTL-by-environmental interactions. However, the substituted segment between SSR603 and TGS0411 markers on chromosome 4 did not affect seed germination. In conclusion, the QTL on chromosome 1 is useful for breeding cultivars that are able to germinate at low temperatures.