Systematic Position of Citrus cavaleriei: Argument for an Independent Subgenus Based on Multidimensional Evidences
1. College of Forestry, Southwest Forestry University, Kunming 650224, China
2. College of Biological Science and Food Engineering, Southwest Forestry University, Kunming 650224, China
| Abstract: | Citrus cavaleriei, a wild germplasm resource within the genus Citrus of the Rutaceae family, holds significant breeding value and a unique taxonomic position. Its systematic status has long been debated, primarily concerning whether it belongs to the Citrus subgenus Papeda, the Citrus subgenus Metacitrus, or should be classified as a distinct genus. To clarify its taxonomic status, this study integrated multi-dimensional research methods—including literature review, comparative morphology, molecular phylogenetic analysis, cytological observation, and ecological adaptability assessment. A multi-evidence framework demonstrates that C. cavaleriei, constitutes an independent evolutionary unit. Morphologically, its winged leaf proportions, floral structures, and seed characteristics distinctly differ from both C. subgenus Papeda and C. subgenus Metacitrus. Molecular systematics confirms it forms an independent phylogenetic branch, with its unique genetic diversity patterns and cold-tolerant gene resources further supporting its distinct subgenus status. Karyotype analysis reveals markedly unique chromosomal architecture in C. cavaleriei. Furthermore, its unique adaptations and restricted alpine ecological niche create effective reproductive isolation from other citrus groups. Therefore, comprehensive data support establishing C. cavaleriei as an independent subgenus within Citrus. This conclusion not only resolves long-standing taxonomic controversies surrounding C. cavaleriei but also provides a theoretical basis for refining the Citrus taxonomic system and conserving and utilizing its germplasm resources. |
| Keywords: | Citrus cavaleriei; Systematic Status; Molecular Phylogenetics; Ecological Adaptability |
| DOI: | 10.57237/j.life.2025.03.001 |
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Received: 29 October 2025
Accepted: 12 December 2025
Published Online: 24 December 2025
Funding
| 1. | 广义宜昌橙的系统演化与生物地理起源研究 (基金号: 31400181) |
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