Relationship between sprouting, glucoside alkaloids and chlorophyll production in potato tubers (Solanum tuberosum)

Consumers are troubled by whether the sprouting and greening of potato tubers accompanied with glucoside alkaloids production. To controlling the production of glucoside alkaloids and sprouting, controlled illumination and gaseous sprouting inhibitors, included citronella essential oil, methyl salicylate and ethylene, were employed, the changes in sprouting rate, chlorophyll, glucoside alkaloids and related key genes expression in biosynthesis pathways of potato tubers during storage were measured. Results showed that potatoes contained more glucoside alkaloids with high sprouting rate, whereas the greening was only affected by light, which was not a sign of glucoside alkaloid production. The sprouting rates of potato (Solanum tuberosum L. cv. Favorita) in the fumigated groups was 31.11 %-37.01 %, the glucoside alkaloids content was 83.35–90.33 mg kg⁻¹, there was no significant difference. However, the potato sprouting rates in the CK were 100 %, and the contents of glucoside alkaloids were 153.34–161.36 mg kg⁻¹, but the chlorophyll contents of potatoes in illumination groups were 19.27–20.51 mg kg⁻¹, which was significantly higher (P > 0.05) than that in dark (1.46–1.85 mg kg⁻¹). These results indicated that the synthesis of glucoside alkaloids was associated with sprouting, and it was feasible to inhibit glucoside alkaloids synthesis by gaseous sprouting suppressants.