Verma Priyanka, Goyal Richa, Chahota R K, Sharma Tilak R, Abdin M Z, Bhatia Sabhyata
National Institute of Plant Genome Research, Post Box No. 10531, Aruna Asaf Ali Marg, New Delhi, 110067, India; Department of Biotechnology, Faculty of Science, Jamia Hamdard, New Delhi, 110062, India.
National Institute of Plant Genome Research, Post Box No. 10531, Aruna Asaf Ali Marg, New Delhi, 110067, India.
PLoS One. 2015 Oct 5;10(10):e0139666. doi: 10.1371/journal.pone.0139666. eCollection 2015.
Seed weight and seed size both are quantitative traits and have been considered as important components of grain yield, thus identification of quantitative trait loci (QTL) for seed traits in lentil (Lens culinaris) would be beneficial for the improvement of grain yield. Hence the main objective of this study was to identify QTLs for seed traits using an intraspecific mapping population derived from a cross between L. culinaris cv. Precoz (seed weight-5.1g, seed size-5.7mm) and L. culinaris cv. L830 (seed weight-2.2g, seed size-4mm) comprising 126 F8-RILs. For this, two microsatellite genomic libraries enriched for (GA/CT) and (GAA/CTT) motif were constructed which resulted in the development of 501 new genomic SSR markers. Six hundred forty seven SSR markers (including 146 previously published) were screened for parental polymorphism and 219 (33.8%) were found to be polymorphic among the parents. Of these 216 were mapped on seven linkage groups at LOD4.0 spanning 1183.7cM with an average marker density of 5.48cM. Phenotypic data from the RILs was used to identify QTLs for the seed weight and seed size traits by single marker analysis (SMA) followed by composite interval mapping (CIM) which resulted in one QTL each for the 2 traits (qSW and qSS) that were co-localized on LG4 and explained 48.4% and 27.5% of phenotypic variance respectively. The current study would serve as a strong foundation for further validation and fine mapping for utilization in lentil breeding programs.
种子重量和种子大小均为数量性状，且被视为籽粒产量的重要组成部分，因此鉴定小扁豆（Lens culinaris）种子性状的数量性状位点（QTL）将有助于提高籽粒产量。因此，本研究的主要目的是利用一个种内作图群体来鉴定种子性状的QTL，该群体源自L. culinaris品种Precoz（种子重量5.1克，种子大小5.7毫米）和L. culinaris品种L830（种子重量2.2克，种子大小4毫米）之间的杂交，包含126个F8重组自交系。为此，构建了两个分别富含（GA/CT）和（GAA/CTT）基序的微卫星基因组文库，从而开发出501个新的基因组SSR标记。对647个SSR标记（包括先前发表的146个）进行亲本多态性筛选，发现其中219个（33.8%）在亲本间具有多态性。其中216个标记定位到7个连锁群上，LOD值为4.0，跨度为1183.7厘摩，平均标记密度为5.48厘摩。利用重组自交系的表型数据，通过单标记分析（SMA），随后进行复合区间作图（CIM）来鉴定种子重量和种子大小性状的QTL，结果这两个性状各鉴定出一个QTL（qSW和qSS），它们共定位于LG4上，分别解释了48.4%和27.5%的表型变异。本研究将为小扁豆育种计划中的进一步验证和精细定位提供坚实基础。
