Methyl salicylate-accelerated cellular NO production improves mitochondrial and cytosolic antioxidants in preserving ‘Sucrier’ banana peel spotting during storage

Abstract

The mitochondria, serving as the central organelle, play a pivotal role in driving cellular processes and orchestrating senescence in plant. Additionally, they are implicated in the occurrence of physiological disorders in harvested crops. This study aimed to elucidate the connection between mitochondrial activity and the development of senescent spotting and uncover the supplementary function of MeSA immersion in facilitating the generation of nitric oxide (NO), which in turn activates the expression of mitochondrial and cytosolic reactive oxygen species (ROS) scavenging enzymes, thereby enhancing their efficiency in neutralizing ROS. The findings of this study revealed a compelling association between diminished mitochondrial activity and the development of peel spotting. Notably, a decline in mitochondrial redox status on day 3 to day 6, as evidenced by triphenyltrtrazolium chloride reduction, coupled with reduction in the expression of antioxidant genes, became increasingly prominent as the severity of spotting lesions intensified, particularly in the vicinity of the affected areas. Intriguingly, treatment with MeSA exhibited a significant elevation in NO accumulation during the initial 3 d coinciding with the upregulation of mitochondrial antioxidant gene expressions. The augmented expression of these genes facilitated the preservation of mitochondrial redox capacity, consequently leading to a reduction in oxidative damage, which corresponded remarkably well with the decrease in peel spotting. Hence, our study highlights the role of MeSA upregulated NO-mediated antioxidative genes, which, in turn, assume a pivotal function in safeguarding mitochondrial integrity and mitigating the occurrence of peel spotting in ‘Sucrier’ bananas.