Fig. 1From: Primary root response to combined drought and heat stress is regulated via salicylic acid metabolism in maizeDynamic change of the primary root lengths under control (CK), drought (D), heat (H) and combined stress (DH) during 9 days after germination. Significant differences in the average lengths at each time point were calculated using the t-test. Different colors of “*” and “**” indicated a significant difference (P < 0.05) and a highly significant difference (P < 0.01), respectively. Begin with day 7, compared with control, the stressed plants showed a highly significant difference, which were indicated by black “**” (P < 0.01)Back to article page