Alterations in Redox Homeostasis and Profound Developmental Consequences Are at the Core of Sudden Gravity Change Responses of Sugarcane Plants

Understanding how abiotic stress influences plant development is important for crop development and management. The gravity changes force may reveal the additional details of the interconnected nature of plants’ stress-signaling pathways. Sugarcane plants were submitted to gravity-changing forces using the VSB-30 sounding rocket to identify how these plants respond to this abiotic stress using histological, biochemical, and molecular approaches to evaluate this response. The histological analysis allowed us to observe that this alteration culminates in the intense disorganization of vascular bundles and higher lignin accumulation in plant cell walls at the adaxial epidermis and the mesophyll cells. An increase in enzyme activity from superoxide dismutase and guaiacol peroxidase was also observed. Our results indicate that sugarcane’s response is similar to other abiotic stress responses, such as oxidative stress. The RNA sequencing data showed that these plantlets had a different expression on pathways associated with signal perception, plant metabolism involving photosynthesis, amino acid synthesis, cell division, DNA repair, and oxidative enzymes for scavenging ROS. These results presented here using sugarcane plantlets expand our knowledge of how plants can respond to the forces of gravity changes. The expression pattern in roots and leaves showed integrated and distinct responses for some known pathways, and both tissues expressed stress-related transcripts.