Juniperus virginiana sourced from colder climates maintain higher ratios of soluble sugars to starch during cold acclimation.

This article investigates how nonstructural carbohydrates (NSCs), specifically soluble sugars and starch, vary during cold acclimation (CA) and drought in Juniperus virginiana L. (eastern red cedar) sourced from different climatic regions, including populations from Florida (FL), New Jersey (NJ), South Dakota (SD), and the closely related Juniperus scopulorum Sarg. from North Dakota (ND). The study found that plants from colder, northern populations exhibited earlier and stronger cold-hardiness responses linked to higher sugar-to-starch ratios, while southern FL plants acclimated more slowly, maintained higher photosynthetic rates in winter, and had lower sugar-to-starch ratios. Drought treatment did not significantly affect NSC concentrations or cold-hardiness, possibly due to the species’ inherent drought tolerance. These findings highlight intraspecific variation in physiological responses to environmental cues, with implications for understanding range expansion and plant adaptation under climate change.