Fig. 4. Metabolites that specifically accumulated in V. amurensis and V. vinifera cv. Muscat Hamburg under the cold stress condition.

a the metabolites that specifically accumulated in V. amurensis; b the metabolites that specifically accumulated in V. vinifera cv. Muscat Hamburg. Time points are the non-stress condition (0) and cold stress at 24 h (24) and 72 h (72). Time points are connected using solid (V. amurensis) or dotted (V. vinifera) lines. Each data point represents the average of six biological replicates with error bars representing the standard deviation. Asterisks (**) and (*) indicate significant differences between the two species at P-value < 0.01 and P-value < 0.05 (Student’s t-test), respectively