Cotton is one of the most important crops among natural fibres. Fibre quality determines the spinning ability, which is negatively correlated with yield and yield-contributing traits. Limited efforts have been made to improve fibre quality and yield in diploid cotton. Therefore, screening a large panel of germplasm lines can help identify genotypes with better fibre quality and yield. We evaluated 712 desi cotton genotypes for fibre quality traits. The genotypes showed a significant difference for all the traits, suggesting considerable variability for fibre quality improvement. Fibre length and strength showed high phenotypic and genotypic coefficients of variation. Heritability was high for fibre strength, length, and elongation. Fibre length and strength were positively correlated; however, micronaire was negatively correlated with these two traits. Superior accessions were identified for fibre length (11), strength (20), uniformity (7), and elongation (25) among genotypes. Most of the desi lines (71%) had medium micronaire values. Twenty accessions identified were ideal for spinning, showing the fibre strength-to-length ratio of one. Cluster analysis based on Euclidean distance grouped all 712 accessions into four major clusters. Principal component analysis biplot revealed that accessions AC3418, 360-SP1, AC3522B, Kanpur A, Gao16CB-9, and AC3370 were genetically diverse. The superior accessions for fibre quality identified in this study are potential lines for the diploid cotton improvement programme.

中文翻译：

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利用纤维品质性状评估二倍体棉花 (Gossypium arboreum L.) 种质的遗传分化

棉花是天然纤维中最重要的作物之一。纤维质量决定了纺丝能力，这与产量和产量贡献性状呈负相关。在提高二倍体棉花的纤维质量和产量方面所做的努力有限。因此，筛选大量种质系可以帮助鉴定具有更好纤维质量和产量的基因型。我们评估了 712 种 desi 棉花基因型的纤维质量性状。基因型在所有性状上均显示出显着差异，表明纤维质量改善存在相当大的可变性。纤维长度和强度表现出较高的表型和基因型变异系数。纤维强度、长度和伸长率的遗传力很高。纤维长度与强度呈正相关；然而，马克隆值与这两个特征呈负相关。鉴定了基因型中纤维长度 (11)、强度 (20)、均匀性 (7) 和伸长率 (25) 的优良种质。大多数 desi 系 (71%) 的马克隆值中等。确定的 20 个种质非常适合纺丝，显示纤维强度与长度之比为 1 个。基于欧几里得距离的聚类分析将所有 712 个种质分为四个主要聚类。主成分分析双图显示，AC3418、360-SP1、AC3522B、Kanpur A、Gao16CB-9 和 AC3370 种质具有遗传多样性。本研究中确定的纤维质量优良的品种是二倍体棉花改良计划的潜在品系。大多数 desi 系 (71%) 的马克隆值中等。确定的 20 个种质非常适合纺丝，显示纤维强度与长度之比为 1 个。基于欧几里得距离的聚类分析将所有 712 个种质分为四个主要聚类。主成分分析双图显示，AC3418、360-SP1、AC3522B、Kanpur A、Gao16CB-9 和 AC3370 种质具有遗传多样性。本研究中确定的纤维质量优良的品种是二倍体棉花改良计划的潜在品系。大多数 desi 系 (71%) 的马克隆值中等。确定的 20 个种质非常适合纺丝，显示纤维强度与长度之比为 1 个。基于欧几里得距离的聚类分析将所有 712 个种质分为四个主要聚类。主成分分析双图显示，AC3418、360-SP1、AC3522B、Kanpur A、Gao16CB-9 和 AC3370 种质具有遗传多样性。本研究中确定的纤维质量优良的品种是二倍体棉花改良计划的潜在品系。主成分分析双图显示，AC3418、360-SP1、AC3522B、Kanpur A、Gao16CB-9 和 AC3370 种质具有遗传多样性。本研究中确定的纤维质量优良的品种是二倍体棉花改良计划的潜在品系。主成分分析双图显示，AC3418、360-SP1、AC3522B、Kanpur A、Gao16CB-9 和 AC3370 种质具有遗传多样性。本研究中确定的纤维质量优良的品种是二倍体棉花改良计划的潜在品系。