基于CRISPR/Cas9的猕猴桃性状改良: 精准育种策略与挑战

Kiwifruit trait improvement via CRISPR/Cas9: Precision breeding strategies and challenges

关键词:  猕猴桃育种, CRISPR/Cas9基因编辑, 全基因组测序, 分子设计育种, 果实品质改良

Key words:  kiwifruit breeding, CRISPR/Cas9 gene editing, whole genome sequencing, molecular design breeding, fruit quality improvement

摘要:

基因编辑技术的快速发展为猕猴桃(Actinidia spp.)的精准育种提供了革命性工具。该文系统综述了CRISPR/Cas9技术在猕猴桃性状改良中的多维应用及其策略与挑战。基于高质量基因组资源(如中华猕猴桃端粒到端粒无间隙参考基因组)与高效遗传转化体系(如无标记农杆菌转化系统),研究者在果实品质、抗病性及株型调控等领域取得了突破性进展:通过靶向编辑AcNAC1、bZIP及MYB/bHLH复合体等关键基因,实现了柠檬酸含量降低、维生素C合成增强与花青素积累优化; 采用宿主-病原体双向策略,强化AcCBL3介导的草酸钙屏障,并干扰病原菌hopAI1毒力基因,显著提升抗病效率; 通过敲除CEN-like、AcFLC-like基因,创制出紧凑株型与非冷依赖萌芽新种质。采后生理研究揭示了乙烯信号通路与细胞壁降解酶系的协同调控网络,为延长货架期提供分子靶标。尽管多倍体编辑复杂性及转基因监管争议仍然存在挑战,但多组学整合与合成生物学工具的介入,正推动着猕猴桃育种从单基因操作向代谢通路重编程跨越。随着全球对无外源DNA编辑品种的政策松绑,基于CRISPR/Cas9的猕猴桃分子设计育种将迎来产业化发展的重要机遇期。此外,该文还进一步探讨了技术优化路径与未来研究方向,为加速猕猴桃突破性品种选育提供了理论框架。

Abstract:

The rapid advancement of gene editing technologies has revolutionized precision breeding in kiwifruit(Actinidia spp.). This review systematically summarizes the multidimensional applications, strategies, and challenges of CRISPR/Cas9 technology in kiwifruit trait improvement. Leveraging high-quality genomic resources, such as the telomere-to-telomere gapless reference genome of A. chinensis, and efficient genetic transformation systems like marker-free Agrobacterium-mediated methods, researchers have achieved breakthroughs in fruit quality, disease resistance, and plant architecture regulation. Key advancements include: targeted editing of AcNAC1, bZIP and MYB/bHLH complexes to reduce citrate content, enhance vitamin C biosynthesis, and optimize anthocyanin accumulation; a host-pathogen dual-targeting strategy that strengthens the AcCBL3-mediated calcium oxalate barrier and disrupts the hopAI1 virulence gene in pathogens, significantly improving disease resistance; and knockout of CEN-like and AcFLC-like genes to develop compact plant architecture and non-cold-independent budbreak germplasms. Postharvest studies have elucidated synergistic regulatory networks between ethylene signaling and cell wall hydrolases, offering molecular targets for shelf-life extension. Despite challenges such as polyploid editing complexity and transgenic regulatory controversies, the integration of multi-omics and synthetic biology tools is advancing kiwifruit breeding from single-gene manipulation to metabolic pathway reprogramming. With global regulatory relaxation for foreign DNA-free edited varieties, CRISPR/Cas9-based molecular design breeding will usher in an important opportunity period of industrial development. In addition, this review further outlines technical optimization pathways and future research priorities, providing a theoretical framework for accelerating the breakthrough breeding of kiwifruit cultivars.