Instituto de Conservación y Mejora de la Agrodiversidad Valenciana, Universitat Politècnica de València, Valencia, Spain.
Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universitat Politècnica de València, Valencia, Spain.
PLoS One. 2018 Jun 27;13(6):e0199943. doi: 10.1371/journal.pone.0199943. eCollection 2018.
Evaluation and prediction of the performance of hybrids is important in eggplant (Solanum melongena) breeding. A set of 10 morphologically highly diverse eggplant parents, including nine inbred S. melongena and one weedy S. insanum accessions, were intercrossed according to a half-diallel mating design without reciprocals to obtain 45 hybrids. Parents and hybrids were evaluated for 14 morphological and agronomic conventional descriptors and 14 fruit morphometric traits using Tomato Analyzer. Genetic distances among parents were estimated with 7,335 polymorphic SNP markers. Wide ranges of variation and significant differences were observed in the set of 55 genotypes for all traits, although the hybrids group had significantly higher vigour and yield than parents. General and specific combining abilities (GCA and SCA) were significant for most (GCA) or all (SCA) traits, although a wide variation was obtained for GCA/SCA ratios. Many relevant traits associated to vigour and yield had low GCA/SCA ratios and narrow-sense heritability (h2) values, while the reverse occurred for most fruit shape descriptors. Broad-sense heritability (H2) values were generally high, irrespective of GCA/SCA ratios. Significant correlations were found between traits related to size of leaf, flower and fruit, as well as among many fruit morphometric traits. Genetic distances (GD) among parents were coherent with their phylogenetic relationships, but few significant and generally low correlations were found between GD and hybrid means, heterosis or SCA. The results provide relevant information for developing appropriate strategies for parent selection and hybrid development in eggplant and suggest that GD among parents have limited value to predict hybrid performance in this crop.
杂种表现的评估和预测在茄子（Solanum melongena）育种中很重要。一组 10 个形态高度多样化的茄子亲本，包括 9 个自交系茄子和 1 个野生茄子种 S. insanum ，按照不完全双列杂交设计进行杂交，没有相互杂交，获得了 45 个杂种。使用番茄分析仪对亲本和杂种进行了 14 个形态和农艺常规描述符和 14 个果实形态计量性状的评估。利用 7335 个多态性 SNP 标记估算了亲本间的遗传距离。在所研究的 55 个基因型中，所有性状均观察到广泛的变异和显著差异，尽管杂种群体的活力和产量显著高于亲本。大多数（一般配合力，GCA）或所有（特殊配合力，SCA）性状的一般和特殊配合力（GCA 和 SCA）均显著，尽管 GCA/SCA 比值变化较大。许多与活力和产量相关的性状的 GCA/SCA 比值和狭义遗传力（h2）值较低，而大多数果实形状描述符则相反。广义遗传力（H2）值普遍较高，与 GCA/SCA 比值无关。发现与叶片、花和果实大小相关的性状之间以及许多果实形态计量性状之间存在显著相关性。亲本间的遗传距离（GD）与其系统发育关系一致，但 GD 与杂种平均值、杂种优势或 SCA 之间的相关性较小且通常较低。研究结果为茄子亲本选择和杂种开发提供了相关信息，并表明亲本间的 GD 对预测该作物杂种表现的价值有限。
