摘要：
背景：表型性状评价对于陆地棉优异品系的选择至关重要。棉花育种者充分利用能够分离出目标性状的不同基因型以创造更多的选择和遗传重组，因此获得更多的表型与分子多样性信息有助于育种亲本的科学选择。
方法：本研究对719份不同来源的陆地棉在连续两年8个不同环境中的5个纤维品质相关性状进行鉴定。基于获得的大量表型数据，利用主成分分析以及通过SNP标记构建系统进化树筛选优异陆地棉种质资源。
结果：我们发现纤维品质性状在两年中的不同环境均表现出广泛的变异。总体而言，国外的品系相对于国内品系具有更长的纤维长度和更高的比强度。比较国内不同植棉区的品系发现北部/西北部的品系具有更好的纤维长度、比强度以及马克隆值。通过对所有表型数据多方法评价，我们筛选出了31份纤维品质达到“双30”（长度≥30 mm，比强度≥30 cN·tex-1）的优异种质。
结论：本研究详尽描述了来源广泛的陆地棉群体的表型多样性，这些结果将为开展棉花优异纤维品质性状育种的亲本选配提供参考。



Evaluation of the genetic diversity of fibre quality traits in upland cotton (Gossypium hirsutum L.) inferred from phenotypic variations 
SUN Zhengwen, WANG Xingfen, LIU Zhengwen, GU Qishen, ZHANG Yan, LI Zhikun, KE Huifeng, YANG Jun, WU Jinhua, WU Liqiang, ZHANG Guiyin and MA Zhiying

Background
Evaluating phenotypic traits is very important for the selection of elite lines in Gossypium hirsutum L. Cotton breeders are interested in using diverse genotypes in hybridization that can segregate for traits of interested with the possibility of selection and genetic gain. Information on phenotypic and molecular diversity helps the breeders for parental selection.
Methods
In this study, 719 global collections of G. hirsutum L. were evaluated for five fibre-related traits during two consecutive years in eight different environments. A series of phenotypic data for fibre quality traits were obtained and the elite accessions were further screened using principal component analysis and phylogenetic tree construction based on single nucleotide polymorphism markers.
Results
We found that fibre quality traits showed a wide range of variation among the G. hirsutum accessions over 2?years. In general, accessions from outside China tended to have higher fibre length (FL) and fibre strength (FS) than did Chinese accessions. Among different regional accessions in China, North/Northwest accessions tended to have the highest FL, FS and best fibre macronaire. By assessing five fibre quality traits over 2?years with genotypic data, 31 elite germplasms reaching double-thirty quality values (FL?≥?30?mm and FS?≥?30 cN·tex??1) were selected.
Conclusions
This study provided a detailed phenotypic diversity description of a population representing a wide range of upland cotton germplasm. Our findings provide useful information about possible elite fibre quality parents for cotton breeding programs.

Journal of Cotton Research. 2019, 2: 22
https://doi.org/10.1186/s42397-019-0041-2
https://jcottonres.biomedcentral.com/articles/10.1186/s42397-019-0041-2