Department of Genetics and Plant Breeding, CPBG, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India.
Department of Oilseeds, CPBG, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India.
PeerJ. 2024 Oct 31;12:e18205. doi: 10.7717/peerj.18205. eCollection 2024.
Sunflower ( L.), known for its adaptability and high yield potential, is vital in global edible oil production. Estimating genetic diversity is a key pre-breeding activity in crop breeding. The current study comprised of 48 genotypes which were assessed for their biometrical traits at department of Oilseeds, Tamil Nadu Agricultural University, during the rainy season of 2022. The lines were subsequently characterised using 103 simple sequence repeat (SSR) markers for molecular diversity analysis. The results indicated that the net nucleotide distances indicated varying genetic divergence, with subpopulations II and V showing the highest (0.056) and I and IV the lowest (0.014). Subpopulation IV exhibited the highest heterozygosity (0.352), while subpopulation III had the lowest heterozygosity and a low Fst (0.173). Principal components analysis (PCA) and hierarchical cluster analysis were employed for assessing the morphological diversity, facilitating genotype grouping and parent selection for breeding programs. The first four components cumulatively accounted for 86.72% of the total variation. Cluster Analysis grouped 48 sunflower genotypes into three clusters based on genetic diversity. COSF 13B stands out for its high head diameter, oil content, seed yield, and oil yield based on mean performance of morphological data. Principal coordinate analysis (PCoA) mirrored the groupings from the Neighbor Joining method, with the first three components explaining 27.24% of the total variation. Molecular data analysis identified five distinct clusters among the germplasm. By integrating morphological and molecular marker data with genetic distance analysis, substantial diversity was revealed with the genotypes RHA 273 and GMU 325 consistently demonstrated high oil yield per plant. The genotypes GMU 477, GMU 450, COSF 13B, RHA 102, CMS 1103B, and RHA GPR 58 have been identified as suitable parents for enhancing oil content in sunflower breeding programs. These findings also aid in selecting SSR markers for genotype characterization and in choosing diverse parents for breeding programs.
向日葵（L.）以其适应性和高产潜力而闻名，是全球食用油生产的重要组成部分。遗传多样性估计是作物育种中前培育的关键活动。本研究包括 48 个基因型，这些基因型在 2022 年雨季在泰米尔纳德邦农业大学的油籽系进行了生物计量性状评估。随后，使用 103 个简单序列重复（SSR）标记对这些系进行了分子多样性分析。结果表明，净核苷酸距离表明存在不同的遗传分化，亚种群 II 和 V 显示出最高的遗传距离（0.056），而 I 和 IV 显示出最低的遗传距离（0.014）。亚种群 IV 表现出最高的杂合性（0.352），而亚种群 III 表现出最低的杂合性和较低的 Fst（0.173）。主成分分析（PCA）和层次聚类分析用于评估形态多样性，便于对基因型进行分组和为育种计划选择亲本。前四个成分累积占总变异的 86.72%。聚类分析根据遗传多样性将 48 个向日葵基因型分为三个组。根据形态数据的平均表现，COSF 13B 在头径、含油量、种子产量和出油率方面表现突出。主坐标分析（PCoA）反映了与邻接法的分组，前三个成分解释了总变异的 27.24%。分子数据分析在种质资源中鉴定出五个不同的聚类。通过将形态和分子标记数据与遗传距离分析相结合，揭示了大量的多样性，基因型 RHA 273 和 GMU 325 始终表现出较高的单株产油量。基因型 GMU 477、GMU 450、COSF 13B、RHA 102、CMS 1103B 和 RHA GPR 58 被鉴定为适合提高向日葵育种计划含油量的亲本。这些发现还有助于选择 SSR 标记对基因型进行特征描述，并选择不同的亲本用于育种计划。
