Key Laboratory of Eco-Environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China.
Chongqing Key Laboratory of Forest Resource Innovation and Utilization, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, School of Life Sciences, Southwest University, Chongqing 400715, China.
Int J Mol Sci. 2024 Nov 17;25(22):12344. doi: 10.3390/ijms252212344.
Heterosis, or hybrid vigor, refers to the phenomenon where hybrid progenies outperform their parents in traits such as yield and resistance. This phenomenon has been widely applied in plant breeding. Recent advances in high-throughput genomics have significantly advanced our understanding of heterosis. This review systematically summarizes the genetic, molecular, and epigenetic mechanisms underlying heterosis. Furthermore, we discuss recent advances in predictive methods for heterosis and their applications in improving growth rate, resistance to abiotic stresses, and wood yield in tree species. We also explore the role of tree genomics in unraveling the mechanisms underlying heterosis, emphasizing the potential of integrating high-resolution genomics, single-cell sequencing, and spatial transcriptomics to achieve a comprehensive understanding of heterosis from the molecular to spatial levels. Building on this, CRISPR-based gene-editing technologies can be employed to precisely edit heterotic loci, enabling the study of allele function. Additionally, molecular marker-assisted selection (MAS) can be utilized to identify heterotic loci in parental lines, facilitating the selection of optimal hybrid combinations and significantly reducing the labor and time costs of hybrid breeding. Finally, we review the utilization of heterosis in tree breeding and provide a forward-looking perspective on future research directions, highlighting the potential of integrating multi-omics approaches and emerging gene-editing tools to revolutionize tree hybrid breeding.
杂种优势，或杂种优势，是指杂种后代在产量和抗性等性状上优于其亲本的现象。这一现象已被广泛应用于植物育种。近年来高通量基因组学的发展极大地促进了我们对杂种优势的理解。本综述系统地总结了杂种优势的遗传、分子和表观遗传机制。此外，我们讨论了杂种优势预测方法的最新进展及其在提高树木生长速度、抗非生物胁迫和木材产量方面的应用。我们还探讨了树木基因组学在揭示杂种优势机制中的作用，强调了整合高分辨率基因组学、单细胞测序和空间转录组学以实现从分子到空间水平全面理解杂种优势的潜力。在此基础上，基于 CRISPR 的基因编辑技术可用于精确编辑杂种优势基因座，从而研究等位基因的功能。此外，分子标记辅助选择（MAS）可用于鉴定亲本系中的杂种优势基因座，从而有助于选择最佳的杂种组合，并显著降低杂种选育的劳动力和时间成本。最后，我们综述了杂种优势在树木育种中的利用，并对未来的研究方向进行了前瞻性展望，强调了整合多组学方法和新兴基因编辑工具的潜力，以彻底改变树木杂种选育。
