Effect of pulsed light on postharvest disease control-related metabolomic variation in melon (Cucumis melo) artificially inoculated with Fusarium pallidoroseum

Abstract

Pulsed light, as a postharvest technology, is an alternative to traditional fungicides, and can be used on a wide variety of fruit and vegetables for sanitization or pathogen control. In addition to these applications, other effects also are detected in vegetal cells, including changes in metabolism and secondary metabolite production, which directly affect disease control response mechanisms. This study aimed to evaluate pulsed ultraviolet light in controlling postharvest rot, caused by Fusarium pallidoroseum in 'Spanish' melon, in natura, and its implications in disease control as a function of metabolomic variation to fungicidal or fungistatic effects. The dose of pulsed light (PL) that inhibited F. pallidoroseum growth in melons (Cucumis melo var. Spanish) was 9 KJ m-2. Ultra-performance liquid chromatography (UPLC) coupled to a quadrupole-time-of-flight (QTOF) mass analyzer identified 12 compounds based on tandem mass spectrometry (MS/MS) fragmentation patterns. Chemometric analysis by Principal Components Analysis (PCA) and Orthogonal Partial Least Squared Discriminant Analysis (OPLS-DA) and corresponding S-Plot were used to evaluate the changes in fruit metabolism. PL technology provided protection against postharvest disease in melons, directly inhibiting the growth of F. pallidoroseum through the upregulation of specific fruit biomarkers such as pipecolic acid (11), saponarin (7), and orientin (3), which acted as major markers for the defense system against pathogens. PL can thus be proposed as a postharvest technology to prevent chemical fungicides and may be applied to reduce the decay of melon quality during its export and storage.

Uncovering the transcriptional molecular dynamics of shelf life extension and system acquired resistance induction toFusarium pallidoroseumin melon fruits by the use of pulsed-light

“…Our study bridges this gap by providing insights into the transcriptional mechanism involved in these processes. The transcriptional expression results of our study align with the metabolomics findings from (Filho et al, 2020), particularly regarding the specialized metabolic pathway of phenylpropanoids. This pathway emerges as a crucial complex adaptive mechanism in response to both biotic and abiotic stressors.…”

“…Pulsed light technology has emerged as a promising method for controlling fungal infections in various fruits during the post-harvest stage. In this context, our study represents a logical continuation of our prior research, which utilized metabolomics technology as detailed in (Filho et al, 2020). The previous study employed the same experimental design to examine the metabolic changes occurring in melon fruits.…”

“…However, a recent study with Musa nana (M.-Z. Chen et al, 2021) described the transcriptional molecular mechanism triggering the defense response against diseases and the up-regulation of metabolite biosynthesis and antioxidant pathways through the use of UV-C. Our group’s previous study, involving metabolomics (Filho et al, 2020), serves as the foundation for this ongoing investigation to better understand the molecular mechanism behind the inducible resistance acquired and the extension of fruit shelf life promoted by UVP, using RNA-seq data. Our transcriptomics study has generated new insights into the molecular mechanism of the beneficial aspects promoted by the application of pulsed light in melons during the post-harvest stage.…”

Postharvest Technologies of Fresh Citrus Fruit: Advances and Recent Developments for the Loss Reduction during Handling and Storage

“…The U.S. Food and Drug Administration (FDA) has recently approved PL technology for food treatments at maximum radiant energy (Fluence) of 12 J cm −2 [75]. Recent investigations have evaluated PL efficacy in pathogen inactivation on the surface of fresh products [76,77], with promising results in controlling pathogen growth in various fruits [78,79].…”

Postharvest Ultraviolet Radiation in Fruit and Vegetables: Applications and Factors Modulating Its Efficacy on Bioactive Compounds and Microbial Growth

“…and Fusarium sp. among others [ 49 , 50 ], with positive effects with regards to reducing disease incidence and severity. Direct germicide action compromising microbial viability has been frequently reported [ 51 ], but less severe effects, such as the reduced germination speed of viable conidia, have also been observed [ 52 ].…”