Dos Santos Caroline Cardoso, de Andrade Luciano Rogerio Braatz, do Carmo Cátia Dias, de Oliveira Eder Jorge
Centro de Ciências Agrárias, Ambientais e Biológicas, Universidade Federal do Recôncavo da Bahia, Cruz das Almas, Bahia, Brazil.
Embrapa Mandioca e Fruticultura, Nugene, Cruz das Almas, Bahia, Brazil.
Front Plant Sci. 2023 Sep 6;14:1250205. doi: 10.3389/fpls.2023.1250205. eCollection 2023.
Cassava ( Crantz) holds significant importance as one of the world's key starchy crop species. This study aimed to develop core collections by utilizing both phenotypic data (15 quantitative and 33 qualitative descriptors) and genotypic data (20,023 single-nucleotide polymorphisms) obtained from 1,486 cassava accessions. Six core collections were derived through two optimization strategies based on genetic distances: Average accession-to-nearest-entry and Average entry-to-nearest-entry, along with combinations of phenotypic and genotypic data. The quality of the core collections was evaluated by assessing genetic parameters such as genetic diversity Shannon-Weaver Index, inbreeding (), observed (), and expected () heterozygosity. While the selection of accessions varied among the six core collections, a seventh collection (consolidated collection) was developed, comprising accessions selected by at least two core collections. Most collections exhibited genetic parameters similar to the complete collection, except for those developed by the Average accession-to-nearest-entry algorithm. However, the variations in the maximum and minimum values of , , and parameters closely resembled the complete collection. The consolidated collection and the collection constructed using genotypic data and the Average entry-to-nearest-entry algorithm (GenEN) retained the highest number of alleles (>97%). Although the differences were not statistically significant (above 5%), the consolidated collection demonstrated a distribution profile and mean trait values most similar to the complete collection, with a few exceptions. The Shannon-Weaver Index of qualitative traits exhibited variations exceeding ±10% when compared to the complete collection. Principal component analysis revealed that the consolidated collection selected cassava accessions with a more uniform dispersion in all four quadrants compared to the other core collections. These findings highlight the development of optimized and valuable core collections for efficient breeding programs and genomic association studies.
木薯（Crantz）作为世界上主要的淀粉类作物品种之一，具有重要意义。本研究旨在利用从1486份木薯种质中获得的表型数据（15个数量性状和33个质量性状描述符）和基因型数据（20,023个单核苷酸多态性）来构建核心种质库。通过基于遗传距离的两种优化策略，即平均种质到最近种质和平均种质到最近条目，以及表型和基因型数据的组合，得出了六个核心种质库。通过评估遗传多样性香农-韦弗指数、近交系数（）、观察到的（）和预期的（）杂合度等遗传参数，对核心种质库的质量进行了评估。虽然六个核心种质库中种质的选择各不相同，但开发了第七个种质库（合并种质库），它由至少两个核心种质库选择的种质组成。除了通过平均种质到最近种质算法开发的种质库外，大多数种质库的遗传参数与完整种质库相似。然而，、和参数的最大值和最小值的变化与完整种质库非常相似。合并种质库以及使用基因型数据和平均种质到最近条目算法（GenEN）构建的种质库保留了最高数量的等位基因（>97%）。虽然差异无统计学意义（超过5%），但合并种质库展示出与完整种质库最相似的分布概况和平均性状值，只有少数例外。与完整种质库相比，质量性状的香农-韦弗指数变化超过±10%。主成分分析表明，与其他核心种质库相比，合并种质库选择的木薯种质在所有四个象限中的分布更为均匀。这些发现突出了为高效育种计划和基因组关联研究开发优化且有价值的核心种质库的重要性。
