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Survival wisdom of Tradescantia spathacea Sw: Trade-off be-tween anthocyanin mediated photoprotection and photosyn-thetic capacity under high light stress

ABSTRACT: Light heterogeneity shapes plant survival, yet how shade-tolerant species balance photoprotection and photosynthesis under changing light remains unclear. Tradescantia spathacea Sw, with green upper and purple-red lower leaf surfaces, exhibits both shade tolerance and high-light acclimation, but the functional specialization of its leaf sides and the underlying trade-off mechanisms are poorly understood. This study exposed T. spathacea to 100% (FL) and 30% (LL) sunlight for 2 years and systematically assessed light adaptation mechanisms through morphological observation, physiological and biochemical detection, and transcriptomic analyses. Results showed that under FL conditions, leaf morphology underwent adaptive remodeling. Anthocyanins accumu-lated specifically in the lower side, thermal dissipation and antioxidant systems were fully activated, while photosynthetic capacity was markedly inhibited, reflecting a survival-priority strategy. Under LL conditions, leaves became broader and flatter, chlorophyll content increased, and the expression of photosynthesis-related genes was upregulated. This enhanced light capture and carbon assimilation efficiency, leading to significantly greater biomass accumulation, reflecting a growth-oriented resource al-location strategy. Transcriptomic and physiological data consistently showed that FL upregulated anthocyanin biosynthetic genes, while LL activated photosystem and photosynthetic electron transport genes. T. spathacea achieves a flexible photoadapta-tion strategy across different light environments through leaf surface functional spe-cialization and an anthocyanin mediated trade-off between photoprotection and pho-tosynthesis.

ORGANISM(S): Tradescantia spathacea

PROVIDER: GSE338282 | GEO | 2026/07/20

REPOSITORIES: GEO

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Survival wisdom of Tradescantia spathacea Sw: Trade-off be-tween anthocyanin mediated photoprotection and photosyn-thetic capacity under high light stress

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