Salicylic acid treatment inhibits cold-induced sweetening by regulating the transcription factors StAP2/ERF and StNAC2 in potato

Abstract

Cold-induced sweetening (CIS) results in browning and acrylamide formation in fried potato products. β-Amylase (BAM) and vacuolar invertase (INV) are crucial for starch-sugar conversion in cold-stored potatoes. This research investigates the effects of salicylic acid treatment on the CIS of potatoes and gene regulation during this process. The findings revealed that the salicylic acid treatment significantly alleviated CIS by suppressing StBAM1 and StINV1 expressions in potatoes. Moreover, the expressions of two transcription factors (TFs), StAP2/ERF and StNAC2, were inhibited by salicylic acid treatment. Transient overexpression of StAP2/ERF and StNAC2 in tobacco leaves increased NtBAM1 and NtINV expressions, thus promoting starch-sugar conversion. Furthermore, the GUS activity demonstrated that the StAP2/ERF and StNAC2 increased the promoter activities of StBAM1 and StINV1. This study identifies new TFs in CIS regulation and provides new ideas for alleviating CIS in potatoes.