Zhu Yue, Jia Huixia, Song Jiangping, Zhang Tingting, Zhang Xiaohui, Yang Wenlong, Tan Yumin, Wang Mengzhen, Zang Jiyan, Wang Haiping
State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, 12 Zhongguancun South Street, Haidian District, Beijing 100081, China.
Hortic Res. 2024 Sep 16;11(12):uhae260. doi: 10.1093/hr/uhae260. eCollection 2024 Dec.
Garlic is a widely utilized condiment and health product. However, garlic bulbs are prone to quality deterioration resulting in decrease of economic value during postharvest. In this study, the storability of 501 garlic accessions worldwide was evaluated based on the examination of decay index (DI), decay rate, sprouting rate, and bud-to-clove ratio in two consecutive years. The DI was employed as a primary index for evaluating the storability of garlic. Among these garlic, 43 accessions exhibited strong storability with DI of 0%-5%. Phenotypic and cytological observations revealed that strong storability accessions displayed delayed sprouting and decay, a slow rate of nutrient transfer to vascular bundles. Through genome-wide association study (GWAS), 234 single-nucleotide polymorphism loci (SNPs) were associated with the storability, which were located in or near 401 genes, which were annotated the functions of resistance, storage substances transport, etc. A total of 44 genes were screened using selective sweep analysis. Transcriptomic analysis was performed at four periods after storage in the 8N035 accession with strong storability and 8N258 accession with weak storability. Compared with 8N035, the upregulated genes in the 8N258 were enriched in photosynthesis and stress response, whereas the downregulated genes were enriched in response of biotic and abiotic stress and defense response. A co-expression network and GWAS identified three hub genes as key regulatory genes. Conjoint analysis of GWAS, selective sweep, and transcriptomic analysis identified 21 important candidate genes. These findings provided excellent resources with storability and vital candidate genes regulating storability for biological breeding of garlic.
大蒜是一种广泛使用的调味品和保健品。然而，大蒜鳞茎在采后容易发生品质劣变，导致经济价值下降。在本研究中，基于连续两年对腐烂指数（DI）、腐烂率、发芽率和芽瓣比的检测，评估了全球501份大蒜种质的耐贮性。将DI作为评价大蒜耐贮性的主要指标。在这些大蒜中，有43份种质表现出较强的耐贮性，DI为0%-5%。表型和细胞学观察表明，耐贮性强的种质发芽和腐烂延迟，营养物质向维管束的转移速率较慢。通过全基因组关联研究（GWAS），发现234个单核苷酸多态性位点（SNP）与耐贮性相关，这些位点位于401个基因内部或附近，这些基因被注释为具有抗性、贮藏物质运输等功能。通过选择性清除分析筛选出44个基因。对耐贮性强的8N035种质和耐贮性弱的8N258种质贮藏后的四个时期进行了转录组分析。与8N035相比，8N258中上调的基因富集在光合作用和胁迫反应中，而下调的基因富集在生物和非生物胁迫反应以及防御反应中。一个共表达网络和GWAS鉴定出三个中心基因作为关键调控基因。GWAS、选择性清除和转录组分析的联合分析鉴定出21个重要的候选基因。这些发现为大蒜的生物学育种提供了具有耐贮性的优良资源和调控耐贮性的重要候选基因。
