Fig. 6.

Increasing the seeding depth exerts stress on the emergence of maize seedlings, with the mesocotyl being the primary organ for responding to this stress. This stress stimulates changes in hormone content, metabolite content, and enzyme activity related to ROS within the mesocotyl. Both hormones and metabolites, as well as antioxidant enzymes, are closely related to the oxidative defense of plants. The results of this study reveal that the enhancement of oxidative defense capacity is the fundamental reason why the mesocotyl is longer and the tolerance to deep sowing is stronger in the inbred line DH65232