Plant Molecular Biology Lab (DBT-BIOCARe), Dept. of Biotechnology and Crop Improvement, College of Horticulture, University of Horticultural Sciences, Bagalkot, Karnataka, 587103, India.
Department of Biotechnology & Crop Improvement, College of Horticulture, Bengaluru, Karnataka, 560065, India.
J Appl Genet. 2020 Sep;61(3):303-312. doi: 10.1007/s13353-020-00556-6. Epub 2020 Apr 2.
Carrot (Daucus carota L.) is acknowledged as a highly valuable vegetable crop. Despite having high demand, limited breeding efforts have been made to develop the varieties and hybrids suitable to wider climatic conditions due to improper characterization of the available germplasm. An accession panel (AP) consisting of 144 accessions of five different root colors representing Asiatic and Western gene pools collected from different parts of India was utilized in the present study. This diverse AP was used to assess the population structure and genetic diversity from 80 polymorphic DNA markers distributed throughout the genome. Population structure, neighbor-joining (NJ) tree, and principal coordinate analysis (PCoA)-based diversity assessment divided the AP into three subpopulations/clusters. Greater than ninety percent polymorphism and the higher average polymorphic information content (͂> 0.50) coupled with higher gene diversity (He) indicating the broad genetic base of the population. Moderate to high F and gene flow (Nm) between the subpopulations revealed a moderate genetic differentiation among Indian carrot accessions owing to the highly outcrossing nature of carrot. Analysis of molecular variance (AMOVA) exhibited higher variation among individuals within the subpopulations (69.00%) or total populations (19.00%) than among the subpopulations (13%) as expected in the single Daucus species used here. The information obtained in the study would benefit the carrot breeders to explore the genetic diversity of the Indian carrots in the carrot breeding program for widening the genetic base and multi-color target trait improvement.
胡萝卜(Daucus carota L.)被公认为一种极具价值的蔬菜作物。尽管需求量很大,但由于对现有种质资源的特征描述不当,适合更广泛气候条件的品种和杂交种的培育工作一直受到限制。本研究利用了一个由来自印度不同地区的五个不同根色的 144 个品种组成的品系(AP),这些品种代表了亚洲和西方基因库。这个多样化的 AP 被用于评估来自整个基因组分布的 80 个多态性 DNA 标记的种群结构和遗传多样性。种群结构、邻接聚类(NJ)树和基于主坐标分析(PCoA)的多样性评估将 AP 分为三个亚群/聚类。超过 90%的多态性和更高的平均多态信息含量(͂>0.50)以及更高的基因多样性(He)表明该群体具有广泛的遗传基础。亚群之间中等至高的 F 和基因流(Nm)表明,由于胡萝卜的高度异交性质,印度胡萝卜品种之间存在中等遗传分化。分子方差分析(AMOVA)表明,亚群内个体之间的变异(69.00%)或总群体之间的变异(19.00%)高于亚群之间的变异(13%),这与这里使用的单一胡萝卜物种的预期相符。本研究获得的信息将有助于胡萝卜育种者在胡萝卜育种计划中探索印度胡萝卜的遗传多样性,以扩大遗传基础和改善多色目标性状。