The potato (Solanum tuberosum L.) ranks among the most consumed agricultural products globally and is nutrient-rich. Exposure of potato tubers’ epidermal and subcutaneous tissues to light results in greening and the production of neurotoxic steroidal glycoalkaloids, which significantly reduces tuber quality, increases food safety risks, and leads to rejection by consumers and the processing industry. This review conducts an in-depth analysis of three key aspects: (1) the differences in various light conditions, namely, the disparities in light sources, wavelengths, intensities, and durations; (2) the characteristics of potato cultivars resistant to greening; and (3) the molecular mechanisms of light-induced biosynthesis of chlorophyll and steroidal glycoalkaloids (SGAs). This review is expected to provide technical support for potato food safety measures and a theoretical foundation for the molecular breeding of green-resistant potato varieties.

This study aimed to investigate the effects of different light qualities on the morphological development, photosynthetic characteristics, stomatal structure, and yield of potato, providing theoretical and practical guidance for optimizing light environments in controlled agricultural systems and enhancing the efficient production of potato microtubers. Six light qualities—white, red, blue, green, far-red, and ultraviolet—were applied to systematically evaluate their effects. The results showed that light quality significantly influenced plant morphological traits and physiological metabolism. Red and blue light demonstrated the most pronounced promotive effects. Under red light, plant height and stem diameter increased by 57.47% and 31.10%, respectively, compared to white light, while single tuber weight increased by 20.09%, despite a 14.96% reduction in tuber number per plant. Blue light significantly enhanced chlorophyll content (by 20.35%) and stomatal density (adaxial stomata increased by 28.85%), leading to a 38.98% increase in tuber number, a 51.79% increase in single tuber weight, and a remarkable 110.37% improvement in total yield per plant, compared to white light. In contrast, green light moderately promoted photosynthesis in lower leaves, but reduced the total yield by 39.90%. Far-red (740 nm) and ultraviolet light (390 nm) severely inhibited plant growth and failed to induce tuber formation. Correlation analysis revealed a highly significant positive relationship between chlorophyll content, net photosynthetic rate, stomatal density, and yield per plant (r = 0.96, p < 0.01). This study systematically evaluated the independent effects of single light quality on potato growth and production for the first time, clarifying the regulatory advantages of red and blue light, and providing important theoretical insights for optimizing the light environment with red and blue light to improve potato microtuber yield. Furthermore, this study provides critical data to support future research on the dynamic optimization of light quality ratio.

Potato tubers undergo greening and accumulate steroidal glycoalkaloids (SGAs) upon light exposure, posing potential food safety risks. In this study, six potato cultivars (“Favorita”, “Lucinda”, “Jizhangshu 12”, “Longshu 10”, “Qingshu 9”, and “Purple Potato”) were subjected to six light treatments (dark, UVA, blue, green, red, and white), and peel color, pigment content, SGAs, and the expression of genes related to light signaling, chlorophyll biosynthesis, and SGA biosynthesis was evaluated. Under green light, the contents of α-solanine and α-chaconine were 76.22 and 171.84 mg/kg fresh weight (FW), respectively; by contrast, their levels under blue and white light were approximately 60% higher. These effects may be mediated by the upregulation of HY5 and COP1 expression, which in turn could regulate the biosynthesis of chlorophyll-related genes (CHID, CHLI1) and SGA-related genes (HMGR, SGT1). Yellow-skinned cultivars exhibited pronounced light sensitivity (chlorophyll 18.47–18.52 mg/kg FW; SGAs up to 290.41 mg/kg FW), whereas red- and purple-skinned cultivars delayed greening through anthocyanin-mediated light attenuation. Collectively, these findings provide a framework for postharvest management and breeding, suggesting that reducing blue light while enhancing green light in spectral illumination, together with the development of anthocyanin-enriched cultivars, may serve as effective strategies to extend shelf life, mitigate food safety risks, and reduce postharvest losses.

Enzymatic browning markedly reduces the processing quality and economic value of potatoes. This study evaluated the effects of copper sulfate (CuSO₄) on potato growth, yield, and enzymatic browning. Quantitative analysis of browning-related enzymes, organic acids, free amino acids, and the browning index (BI) was conducted using high-performance liquid chromatography and non-contact colorimetric technology. Moderate Cu²⁺ (0.078–0.157 mmol·L⁻¹) supply enhanced photosynthetic capacity, biomass, and starch accumulation, whereas excessive Cu induced oxidative stress, increased PPO activity, phenolic accumulation, and BI. Metabolic profiling revealed that Cu²⁺ activates PPO via its copper-binding sites and reprograms amino acid and organic acid metabolism—upregulating arginine and proline while downregulating isoleucine, leucine, phenylalanine, lysine, citrate, and chlorogenic acid, all strongly correlated with BI. These findings highlight the dual role of copper in yield formation and enzymatic browning, introducing metabolic reprogramming as a potential mechanism for optimizing Cu fertilization to balance productivity and postharvest quality.