Analysis of factors influencing greening and glycoalkaloids

Wednesday, July 28, 2021
2:40 PM - 3:00 PM

Light-induced accumulation of steroidal glycoalkaloids (SGAs) and concurrent greening of tubers is a major problem, which some have estimated can cause up to 15% - 17% of the crop to be culled. Factors that determine how a given genotype responds to environmental signals that cause greening or increases in SGAs are not fully understood. Transcriptomic and metabolomic approaches were applied to monitor levels of SGA, chlorophyll (CHL), and carotenoid (CAR), and 35 target genes (SGA and CHL associated genes) in potatoes exposed to light. Network analysis was used to look at relationships between metabolites and gene expression. Not all genotypes responded the same way to light, with some more resistant to greening or light-induced SGA increases. In some cases, little or no increase in SGAs was observed in potatoes that had greened. An inverse relationship was observed between increases in CARs and SGAs in response to light. These findings provide insights into mechanisms that control levels of SGA and suggest potato breeding programs may benefit from evaluating the spiking potential of breeding lines.