Differential expression of leaf proteome of tolerant and susceptible maize (<i>Zea mays</i> L.) genotypes in response to multiple abiotic stresses

In the present work, tropical maize genotypes were evaluated for multiple stresses (drought × low-N and waterlogging × low-N) applied simultaneously to 30-day-old maize seedlings. Two-dimensional gel electrophoresis was used to examine the protein changes induced by combined stress, in leaves, of tolerant and susceptible genotypes. Moreover, physiological and biochemical parameters were assessed to understand the physiological status of tolerant and susceptible genotypes under combined stress. The results show that up-regulated proteins of the tolerant genotype have a significant role in activating defense response, restoration of plant growth, and to maintain metabolic homeostasis under stressful conditions. Therefore, they contribute to improve and maintain the state of acclimation of the genotype under stress. Alternatively in the susceptible genotype, the up-regulated proteins are representative biomarkers of stress or are involved in the defense against pathogens and efforts to maintain energy metabolism. Thus, protecting the survival of the genotype under multiple stress conditions. We conclude that depending on the given stress treatment, tolerant and susceptible genotypes differed in stress-enduring approaches. Therefore, the study provides insight to comprehend the response of tolerant and susceptible genotypes under combined stress conditions, which could be valuable for further research and will demonstrate that it is advantageous to select combined stress-tolerant genotypes.