Chen Mengjiao, Song Xiaobo, Wu Shuang, Yu Anjie, Wei Xin, Qiu Jie, Pei Dong
State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091 China.
Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, 200234 China.
Mol Breed. 2025 May 24;45(6):50. doi: 10.1007/s11032-025-01572-2. eCollection 2025 Jun.
Walnut ( L.), an important woody oil plant, is cultivated globally and has a prominent position in the world's major nuts. Heterozygosity enriches plant genetic diversity by providing a wider array of gene combinations, significantly enhancing their adaptability to the environment and consequently improving their survival ability. In this study, we found that the heterozygosity rate was significantly correlated with 21 traits. Heterogeneity rate showed the strongest positive correlation with yield and nutrition, while it showed the most significant negative correlation with tree height and precocity. Among these, 13 traits showed positive correlations, the remaining 8 traits exhibited negative correlations. We conducted an in-depth study on the characteristics of walnut whole-genome heterozygosity. By using the GWAS based on the heterozygosity rate, we successfully identified 11 significant loci and 4 candidate genes. In the analysis of local heterozygosity rate by GWAS, it was found that 63.8% exhibited trans-acting and 36.2% exhibited cis-acting. In addition, with the help of genomic residual heterozygotes, we enriched functional genes from 44 Pfam families related to growth regulation and development. Finally, it is worth mentioning that during the process of walnut improvement, we observed an increase in the heterozygosity rate of genes related to the flowering time. It is speculated that a higher level of whole-genome heterozygosity can enhance the environmental adaptability of plants and improve their growth performance. The results of this study may provide assistance for optimizing the breeding strategies of walnuts.
The online version contains supplementary material available at 10.1007/s11032-025-01572-2.
核桃（Juglans regia L.）是一种重要的木本油料植物，在全球范围内广泛种植，在世界主要坚果中占据显著地位。杂合性通过提供更广泛的基因组合丰富了植物的遗传多样性，显著增强了它们对环境的适应性，从而提高了它们的生存能力。在本研究中，我们发现杂合率与21个性状显著相关。杂合率与产量和营养的正相关性最强，而与树高和早熟的负相关性最显著。其中，13个性状呈正相关，其余8个性状呈负相关。我们对核桃全基因组杂合性的特征进行了深入研究。通过基于杂合率的全基因组关联研究（GWAS），我们成功鉴定出11个显著位点和4个候选基因。在通过GWAS分析局部杂合率时，发现63.8%表现为反式作用，36.2%表现为顺式作用。此外，借助基因组残留杂合子，我们从44个与生长调控和发育相关的Pfam家族中富集了功能基因。最后，值得一提的是，在核桃改良过程中，我们观察到与开花时间相关基因的杂合率有所增加。推测较高水平的全基因组杂合性可以增强植物对环境的适应性并改善其生长性能。本研究结果可能为优化核桃育种策略提供帮助。
在线版本包含可在10.1007/s11032-025-01572-2获取的补充材料。
