Effect of drought stress on growth parameters, osmolyte contents, antioxidant enzymes and glycyrrhizin synthesis in licorice (Glycyrrhiza glabra L.) grown in the field

Hypothetical interaction network in response to drought stress in Licorice. The red rectangle includes genes involved in the glycyrrhizin biosynthesis pathway in licorice plants. The expression of genes encoding these enzymes in slight (S), moderate (M) and intense (I) drought stress is shown in the heatmap. Genes are depicted using fold change values and colour coded to reflect changes in relative expression. Each arrow represents the enzyme reactions: FPP, farnesyl pyrophosphate; SQS, squalene synthase; bAS, beta-amyrin synthase; LUS, lupeol synthase; CAS, cycloartenol synthase; CYP88D6 and CYP72A154, cytochrome P450 monooxygenases; UGTs, UDP-glucuronosyltransferases.230