Abstract

Key message

cqSW.A03-2, one of the six identified quantitative trait loci associated with thousand-seed weight in rapeseed, is mapped to a 61.6-kb region on chromosome A03 and corresponds to the candidate gene BnaA03G37960D.

Abstract

Seed weight is an important factor that determines the seed yield of oilseed rape (Brassica napus L.). To elucidate the genetic mechanism of thousand-seed weight (TSW), quantitative trait locus (QTL) mapping was conducted using a double haploid population derived from the cross between an elite line ZY50 and a pol cytoplasmic male sterility restorer line 7-5. The genetic basis of TSW was dissected into six major QTLs. One major QTL denoted as cqSW.A03-2, which explained 8.46–13.70% of the phenotypic variation, was detected across multiple environments. To uncover the genetic basis of cqSW.A03-2, a set of near-isogenic lines were developed. Based on the test of self-pollinated progenies, cqSW.A03-2 was identified as a single Mendelian factor and the ZY50 allele at cqSW.A03-2 showed a positive effect on TSW. Fine mapping delimited the cqSW.A03-2 locus into a 61.6-kb region, and 18 genes within this region were predicted. Candidate gene association analysis and expression analysis indicated that a histidine kinase gene (BnaA03G37960D) is likely to be the candidate gene for the cqSW.A03-2 locus. Our results may contribute to a better understanding of the molecular mechanism of seed weight regulation and promote the breeding program for yield improvement in rapeseed.

中文翻译：

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菜籽（甘蓝型油菜）千粒重的遗传解剖和cqSW.A03-2的遗传连锁分析

摘要

关键信息

cqSW.A03-2是已鉴定的与油菜千粒重相关的六个定量性状基因座之一，位于染色体A03的61.6-kb区域，与候选基因BnaA03G37960D对应。

抽象

种子重量是决定油菜（甘蓝型油菜）种子产量的重要因素。为了阐明千粒重（TSW）的遗传机制，使用来源于优良品系ZY50和pol细胞质雄性不育恢复系7-5杂交的双单倍体种群进行了性状基因座（QTL）定位。TSW的遗传基础分为六个主要的QTL。表示为一个主效QTL cqSW.A03 - 2，其中说明的表型变异8.46-13.70％时，在多种环境检测。为了揭示的遗传基础cqSW.A03 - 2，一组近等基因系的开发工作。根据自花传粉后代cqSW.A03的测试- 2被确定为一个单一的孟德尔因子，并在ZY50等位基因cqSW.A03 - 2显示对TSW具有积极效果。精细定位限定的cqSW.A03 - 2个轨迹到61.6-kb的区域，并且在该区域内的18个基因进行了预测。候选基因关联分析和表达分析表明，组氨酸激酶基因（BnaA03G37960D）很可能是对所述候选基因cqSW.A03 - 2个基因座中。我们的结果可能有助于更好地了解种子重量调节的分子机制，并促进提高油菜产量的育种计划。