Phytosulfokine promotes fruit ripening and quality via phosphorylation of transcription factor DREB2F in tomato.

Phytosulfokine (PSK), a plant peptide hormone with a wide range of biological functions, is recognized by its receptor PHYTOSULFOKINE RECEPTOR 1 (PSKR1). Previous studies have reported that PSK plays important roles in plant growth, development, and stress responses. However, the involvement of PSK in fruit development and quality formation remains largely unknown. Here, using tomato (Solanum lycopersicum) as a research model, we show that exogenous application of PSK promotes the initiation of fruit ripening and quality formation, while these processes are delayed in pskr1 mutant fruits. Transcriptomic profiling revealed that molecular events and metabolic pathways associated with fruit ripening and quality formation are affected in pskr1 mutant lines and transcription factors are involved in PSKR1-mediated ripening. Yeast screening further identified that DEHYDRATION-RESPONSIVE ELEMENT BINDING PROTEIN 2F (DREB2F) interacts with PSKR1. Silencing of DREB2F delayed the initiation of fruit ripening and inhibited the promoting effect of PSK on fruit ripening. Moreover, the interaction between PSKR1 and DREB2F led to phosphorylation of DREB2F. PSK improved the efficiency of DREB2F phosphorylation by PSKR1 at the tyrosine-30 site, and the phosphorylation of this site increased the transcription level of potential target genes related to the ripening process and functioned in promoting fruit ripening and quality formation. These findings shed light on the involvement of PSK and its downstream signaling molecule DREB2F in controlling climacteric fruit ripening, offering insights into the regulatory mechanisms governing ripening processes in fleshy fruits.

DNA and coding/non-coding RNA methylation analysis provide insights into tomato fruit ripening.

Ripening is the last, irreversible developmental stage during which fruit become palatable, thus promoting seed dispersal by frugivory. In Alisa Craig fruit, mRNAs with increasing m5C levels, such as STPK and WRKY 40, were identified as being involved in response to biotic and abiotic stresses. Furthermore, two mRNAs involved in cell wall metabolism, PG and EXP-B1, also presented increased m5C levels. In the Nr mutant, several m5C-modified mRNAs involved in fruit ripening, including those encoding WRKY and MADS-box proteins, were found. Targets of long non-coding RNAs and circular RNAs with different m5C sites were also found; these targets included 2-alkenal reductase, soluble starch synthase 1, WRKY, MADS-box, and F-box/ketch-repeat protein SKIP11. A combined analysis of changes in 5mC methylation and mRNA revealed many differentially expressed genes with differentially methylated regions encoding transcription factors and key enzymes related to ethylene biosynthesis and signal transduction; these included ERF084, EIN3, AP2/ERF, ACO5, ACS7, EIN3/4, EBF1, MADS-box, AP2/ERF, and ETR1. Taken together, our findings contribute to the global understanding of the mechanisms underlying fruit ripening, thereby providing new information for both fruit and post-harvest behavior.

FERMT2 upregulation in CAFs enhances EMT of OSCC and M2 macrophage polarization.

OBJECTIVES: FERMT2 upregulation was associated with malignant tumor behaviors, including epithelial-to-mesenchymal (EMT). This study aimed to characterize the expression profile of FERMT2 in oral squamous cell carcinoma (OSCC) and to explore its involvement in the tumor microenvironment sculptured by oral cancer-associated fibroblasts (OCAFs). MATERIALS: Previous bulk-seq (TCGA-HNSC) and single-cell RNA-seq data sets were retrieved for bioinformatic analysis. Human OSCC lines SCC15 and CAL27, primary normal oral fibroblasts (NOFs), OCAFs, and THP-1 cells were used for intro studies. RESULTS: FERMT2 expression was significantly higher in CAFs compared with OSCC tumor cells and normal fibroblasts. Higher FERMT2 expression might independently predict unfavorable disease-specific survival (DSS) in patients with OSCC. Knockdown of FERMT2 suppressed the expression and secretion of IGFBP7, SPARC, TIMP3, COL4A1, and IGFBP4 in OCAFs. OCAFs with FERMT2 knockdown had significantly weakened capability to induce the invasion of OSCC cells and the expression of mesenchymal markers. FERMT2 knockdown impaired the inducing effect of OCAFs on the migration of M0 macrophages and the expression of M2 macrophage markers. CONCLUSIONS: FERMT2 could modulate the production and secretion of IGFBP7, SPARC, COL4A1, and IGFBP4 in OCAFs, thereby inducing the EMT of OSCC and M2 macrophage polarization.

The role and interaction between transcription factor NAC-NOR and DNA demethylase SlDML2 in the biosynthesis of tomato fruit flavor volatiles.

Flavor-imparting volatile chemicals accumulate as fruits ripen, making major contributions to taste. The NAC transcription factor nonripening (NAC-NOR) and DNA demethylase 2 (SlDML2) are essential for tomato fruit ripening, but details of the potential roles and the relationship between these two regulators in the synthesis of volatiles are lacking. Here, we show substantial reductions in fatty acid and carotenoid-derived volatiles in tomato slnor and sldml2 mutants. An unexpected finding is the redundancy and divergence in volatile profiles, biosynthetic gene expression, and DNA methylation in slnor and sldml2 mutants relative to wild-type tomato fruit. Reduced transcript levels are accompanied by hypermethylation of promoters, including the NAC-NOR target gene lipoxygenase (SlLOXC) that is involved in fatty acid-derived volatile synthesis. Interestingly, NAC-NOR activates SlDML2 expression by directly binding to its promoter both in vitro and in vivo. Meanwhile, reduced NAC-NOR expression in the sldml2 mutant is accompanied by hypermethylation of its promoter. These results reveal a relationship between SlDML2-mediated DNA demethylation and NAC-NOR during tomato fruit ripening. In addition to providing new insights into the metabolic modulation of flavor volatiles, the outcome of our study contributes to understanding the genetics and control of fruit ripening and quality attributes in tomato.

Transmission Line Sag Measurement and Simulation Research Based on Non-Contact Electric Field Sensing.

Sag is an important indicator of the operational health of a transmission line, and its timely measurement is of great significance to maintain the stability and reliability of power systems. However, traditional contact measurements may be affected by the electromagnetic interference of conductors. In contrast, measurement methods without direct electrical contact with the subject provide greater portability and flexibility. This paper presents a study of a transmission line sag measurement and simulation based on non-contact electric field sensing. The finite element method was used to analyze the conductor distribution, establish the coupling relationships among the electric field, transmission line, and measurement point, propose a sag inverse calculation model, and assess the impact of the transmission line parameter on the curved drooping measurement. Simultaneously, sag measurement schemes for single-round and dual-circuit lines were designed for multi-conductive lines, and measurement array studies were conducted. The vertical component of the electric field in space measured by the array was obtained, which could be used to perform conductor sag measurement simply and efficiently. The proposed method will facilitate the monitoring of the overhead transmission line status, which is conducive to the effective operation of the entire system.

Relationships between genome methylation, levels of non-coding RNAs, mRNAs and metabolites in ripening tomato fruit.

Ripening of tomato fruit is a complex tightly orchestrated developmental process that involves multiple physiological and metabolic changes that render fruit attractive, palatable and nutritious. Ripening requires initiation, activation and coordination of key pathways at the transcriptional and post-transcriptional levels that lead to ethylene synthesis and downstream ripening events determining quality. We studied wild-type, Gr and r mutant fruits at the coding and non-coding transcriptomic, metabolomic and genome methylation levels. Numerous differentially expressed non-coding RNAs were identified and quantified and potential competing endogenous RNA regulation models were constructed. Multiple changes in gene methylation were linked to the ethylene pathway and ripening processes. A combined analysis of changes in genome methylation, long non-coding RNAs, circular RNAs, micro-RNAs and fruit metabolites revealed many differentially expressed genes (DEGs) with differentially methylated regions encoding transcription factors and key enzymes related to ethylene or carotenoid pathways potentially targeted by differentially expressed non-coding RNAs. These included ACO2 (targeted by MSTRG.59396.1 and miR396b), CTR1 (targeted by MSTRG.43594.1 and miR171b), ERF2 (targeted by MSTRG.183681.1), ERF5 (targeted by miR9470-3p), PSY1 (targeted by MSTRG.95226.7), ZISO (targeted by 12:66127788|66128276) and NCED (targeted by MSTRG.181568.2). Understanding the functioning of this intricate genetic regulatory network provides new insights into the underlying integration and relationships between the multiple events that collectively determine the ripe phenotype.

High CO2 - and pathogen-driven expression of the carbonic anhydrase ßCA3 confers basal immunity in tomato.

Atmospheric CO2 concentrations exert a strong influence on the susceptibility of plants to pathogens. However, the mechanisms involved in the CO2 -dependent regulation of pathogen resistance are largely unknown. Here we show that the expression of tomato (Solanum lycopersicum) ß-CARBONIC ANHYDRASE 3 (ßCA3) is induced by the virulent pathogen Pseudomonas syringae pv. tomato DC3000. The role of ßCA3 in the high CO2 -mediated response in tomato and two other Solanaceae crops is distinct from that in Arabidopsis thaliana. Using ßCA3 knock-out and over-expression plants, we demonstrate that ßCA3 plays a positive role in the activation of basal immunity, particularly under high CO2 . ßCA3 is transcriptionally activated by the transcription factor NAC43 and is also post-translationally regulated by the receptor-like kinase GRACE1. The ßCA3 pathway of basal immunity is independent on stomatal- and salicylic-acid-dependent regulation. Global transcriptome analysis and cell wall metabolite measurement implicate cell wall metabolism/integrity in ßCA3-mediated basal immunity under both CO2 conditions. These data not only highlight the importance of ßCA3 in plant basal immunity under high CO2 in a well-studied susceptible crop-pathogen system, but they also point to new targets for disease management strategies in a changing climate.

SRNAome and transcriptome analysis provide insight into strawberry fruit ripening.

Strawberry fruit ripening is a complex process affected by multiple factors at different regulation levels. To elucidate the regulation mechanisms, the combined analysis of sRNAome and transcriptome were used. A total of 124 known and 190 novel miRNAs were found, 62 of them were significantly differentially expressed (DE). The targets of the DE miRNAs were parsed and several TFs, such as SPL, ARF, WRKY, and TCP, were found to be involved in ripening. Elevated CO2 can significantly postpone ripening and miR156, miR166f, miR171a, and miR171d were the DE miRNAs. Transcriptome analysis found 313 DE genes related to fruit ripening, including cell wall metabolism-related genes, color-related genes, ethylene-related genes, and genes encoding TFs such as MYB, SPL, NAC, TCP, and ARF. Based on above, a combined regulatory model involved in fruit ripening was created. These results provide valuable information for understanding the complicated coordinated regulatory network of strawberry fruit ripening.

BCCIPß facilitates p53 ubiquitination via binding with E6 protein in high-risk HPV positive head and neck squamous cell carcinoma.

BRCA2 And CDKN1A Interacting Protein (BCCIP) is initially identified as a tumor suppressor. Some recent studies confirmed its p53 binding capability. In this study, we explored the regulatory effect of BCCIPß on p53 stability in HPV-positive and HPV-negative HNSCC cells. RNA-seq data from TCGA-HNSC were extracted for transcript isoform analysis in HPV-positive and HPV-negative tumors. HPV16-positive UM-SCC-47 (SCC47) and UM-SCC-104 (SCC104) and HPV-negative SCC-9 (SCC9) and UM-SCC-1 (SCC1) cell lines were used as in vitro cell models. Results showed that BCCIPß was the dominant transcript in both HPV-positive and HPV-negative HNSCC cases. Knockdown of BCCIPß decreased p53 protein concentration in the two HPV-negative cell lines but increased p53 concentration in the two HPV-positive cell lines. BCCIPß inhibition increased proliferation and G1/S transition of SCC9 and SCC1 cells. In comparison, BCCIPß inhibition slowed proliferation and increased G1 arrest of SCC104 and SCC47 cells. BCCIPß inhibition prolonged the half-life of p53 protein and reduced p53 ubiquitination in the two HPV16-positive cell lines. Co-IP assay confirmed interactions among BCCIPß, HPV E6, and p53 in both SCC104 and SCC47 cells. In comparison, only the interaction between BCCIPα and p53 was confirmed in these two cell lines. Either E6 or BCCIPß inhibition reduced p53 ubiquitination and increased p53 concentration. However, inhibiting E6 and BCCIPß at the same did not generate synergistic effects. On the contrary, p53 ubiquitination level was even higher in the combination group, with lower p53 concentration compared to the shE6 group. BCCIPß overexpression in SCC47 cells with HPV E6 depletion significantly reduced p53 ubiquitination. In conclusion, this study found a novel interaction between HPV E6 and BCCIPß in HPV16-positive HNSCC cells. The presence of HPV E6 turned BCCIPß from a p53 stabilizer to a ubiquitination facilitator. This mechanism helps explain why BCCIPß acted as a tumor suppressor in HPV-negative HNSCC but exerted oncogenic function in HPV16-positive HNSCC.

Noncoding RNAs: functional regulatory factors in tomato fruit ripening.

Tomato has emerged as the model system for investigations into the regulation of fleshy-fruit ripening and senescence, and the ripening process involving the coordinated regulation at the gene/chromatin/epigenetic, transcriptional, post-transcriptional and protein levels. Noncoding RNAs play important roles in fruit ripening as important transcriptional and post-transcriptional regulatory factors. In this review, we systematically summarize the recent advances in the regulation of tomato fruit ripening involved in ethylene biosynthesis and signal transduction, fruit pigment accumulation, fruit flavor and aroma, fruit texture by noncoding RNAs and their coordinate regulatory network model were set up and also suggest future directions for the functional regulations of noncoding RNAs on tomato fruit ripening.

An untargeted metabolomic approach reveals significant postharvest alterations in vitamin metabolism in response to LED irradiation in pak-choi (Brassica campestris L. ssp. chinensis (L.) Makino var. communis Tsen et Lee).

The main objective of this study was to investigate the effect of low-level light emitting diode (LED) irradiation on the metabolite profile of pak-choi. A total of 633 different molecular features (MFs) were identified among sample groups (initial, dark-treated, light-treated) using an untargeted metabolomic approach. The identified metabolites were associated with 24 different metabolic pathways. Four of the pathways including carbon pool by folate, folate biosynthesis, thiamine metabolism, and glutathione metabolism, all of which are associated with vitamin biosynthesis, changed significantly. Metabolites in four of the pathways exhibited significant differences from the control in response to LED irradiation. Additionally, porphyrin and chlorophyll metabolism, as well as glucosinolate biosynthesis, riboflavin metabolism, and carotenoid biosynthesis were positively induced by LED irradiation. These results indicate that postharvest LED illumination represents a potential tool for modifying the metabolic profile of pak-choi to maintain quality and nutritional levels.

Effect of low-temperature conditioning combined with methyl jasmonate treatment on the chilling resistance of eggplant (Solanum melongena L.) fruit.

Chilling injury (CI) can injure harvested eggplants and lead to a reduction in postharvest quality. The present study examined the effect of low-temperature conditioning (LTC) combined with a methyl jasmonate (MeJA) treatment on CI by analyzing the visual appearance and physiology of eggplants stored at 4 °C. Results indicated that treatment of eggplants with LTC + MeJA effectively maintained the visual quality of eggplants, inhibited a decline in chlorophyll and total phenolics, delayed the accumulation of malondialdehyde (MDA), decreased polyphenol oxidase (PPO) gene expression and enzyme activity, and enhanced the activity of the antioxidant enzymes, catalase (CAT) and peroxidase (POD), as well as the expression of their corresponding genes. Collectively, the data indicate that LTC combined with MeJA effectively improves the CI tolerance of postharvest eggplant fruit stored at 4 °C, by enhancing the activity and relative gene expression of antioxidant enzymes.

A Viral Satellite DNA Vector (TYLCCNV) for Functional Analysis of miRNAs and siRNAs in Plants.

With experimental and bioinformatical methods, numerous small RNAs, including microRNAs (miRNAs) and short interfering RNAs (siRNAs), have been found in plants, and they play vital roles in various biological regulation processes. However, most of these small RNAs remain to be functionally characterized. Until now, only several viral vectors were developed to overexpress miRNAs with limited application in plants. In this study, we report a new small RNA overexpression system via viral satellite DNA associated with Tomato yellow leaf curl China virus (TYLCCNV) vector, which could highly overexpress not only artificial and endogenous miRNAs but also endogenous siRNAs in Nicotiana benthamiana First, we constructed basic TYLCCNV-amiRPDS(319L) vector with widely used AtMIR319a backbone, but the expected photobleaching phenotype was very weak. Second, through comparing the effect of backbones (AtMIR319a, AtMIR390a, and SlMIR159) on specificity and significance of generating small RNAs, the AtMIR390a backbone was optimally selected to construct the small RNA overexpression system. Third, through sRNA-Seq and Degradome-Seq, the small RNAs from AtMIR390a backbone in TYLCCNV-amiRPDS(390) vector were confirmed to highly overexpress amiRPDS and specifically silence targeted PDS gene. Using this system, rapid functional analysis of endogenous miRNAs and siRNAs was carried out, including miR156 and athTAS3a 5'D8(+). Meanwhile, through designing corresponding artificial miRNAs, this system could also significantly silence targeted endogenous genes and show specific phenotypes, including PDS, Su, and PCNA These results demonstrated that this small RNA overexpression system could contribute to investigating not only the function of endogenous small RNAs, but also the functional genes in plants.

Analysis of the Coding and Non-Coding RNA Transcriptomes in Response to Bell Pepper Chilling.

Increasing evidence suggests that long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and microRNAs (miRNAs) have roles during biotic and abiotic stress, though their exact contributions remain unclear. To explore their biological functions in response to chilling in bell pepper, we examined their accumulation profiles by deep sequencing and identified 380 lncRNAs, 36 circRNAs, 18 miRNAs, and 4128 differentially expressed mRNAs in the chilled versus the non-chilled fruit. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed differentially expressed genes and putative ncRNA targets, including transcription factors of multiple classes, such as myeloblastosis (MYB), basic helix-loop-helix (bHLH), and ethylene response factor (ERF) transcription factors (TFs), enzymes involved in bio-oxidation and oxidative phosphorylation (serine/threonine-protein kinase, polyphenol oxidase, catalase, peroxidase, lipoxygenase, and ATPase), and cell wall metabolism-related enzymes (beta-galactosidase, pectate lyase, pectinesterase, and polygalacturonase). On the basis of the accumulation profiles, a network of putatively interacting RNAs associated with bell pepper chilling was developed, which pointed to ncRNAs that could provide the foundation for further developing a more refined understanding of the molecular response to chilling injury.

Integrative analysis of circRNAs acting as ceRNAs involved in ethylene pathway in tomato.

Circular RNAs (circRNAs) are a large class of non-coding endogenous RNAs that could act as competing endogenous RNAs (ceRNAs) to terminate the mRNA targets' suppression of miRNAs. To elucidate the intricate regulatory roles of circRNAs in the ethylene pathway in tomato fruit, deep sequencing and bioinformatics methods were performed. After strict screening, a total of 318 circRNAs were identified. Among these circRNAs, 282 were significantly differentially expressed among wild-type and sense-/antisense-LeERF1 transgenic tomato fruits. Besides, 1254 target genes were identified and a large amount of them were found to be involved in ethylene pathway. In addition, a sophisticated regulatory model consisting of circRNAs, target genes and ethylene was set up. Importantly, 61 circRNAs were found to be potential ceRNAs to combine with miRNAs and some of the miRNAs had been revealed to participate in the ethylene signaling pathway. This research further raised the possibility that the ethylene pathway in tomato fruit may be under the regulation of various circRNAs and provided a new perspective of the roles of circRNAs.

SRNAome and degradome sequencing analysis reveals specific regulation of sRNA in response to chilling injury in tomato fruit.

Plant genomes encode diverse small RNA classes that function in distinct gene-silencing pathways. To elucidate the intricate regulation of microRNAs (miRNAs) and endogenous small-interfering RNAs (siRNAs) in response to chilling injury in tomato fruit, the deep sequencing and bioinformatic methods were combined to decipher the small RNAs landscape in the control and chilling-injured groups. Except for the known miRNAs and ta-siRNAs, 85 novel miRNAs and 5 ta-siRNAs members belonging to 3 TAS families (TAS5, TAS9 and TAS10) were identified, 34 putative phased small RNAs and 740 cis/trans-natural antisense small-interfering RNAs (nat-siRNAs) were also found in our results which enriched the tomato small RNAs repository. A large number of genes targeted by those miRNAs and siRNAs were predicted to be involved in the chilling injury responsive process and five of them were verified via degradome sequencing. Based on the above results, a regulatory model that comprehensively reveals the relationships between the small RNAs and their targets was set up. This work provides a foundation for further study of the regulation of miRNAs and siRNAs in the plant in response to chilling injury.

Deciphering the roles of circRNAs on chilling injury in tomato.

Various circular RNAs (circRNAs) are newly identified in animals and plants through high-throughput deep sequencing which play important roles in miRNA function and transcriptional controlling. However, little is known regarding circRNAs in tomato fruit. In this study, we systematically parse the circRNAs in the whole genome using the combination methods of deep sequencing and bioinformatics. In all, 854 circRNAs were identified in our results, among them, 163 circRNAs exhibit chilling responsive expression. Intriguingly, several circRNAs were predicted to involved in chilling responsive process, such as redox reaction, cell wall degradation, Arginine and polyamine metabolism, heat and cold shock protein, energy metabolism, Jasmonic acid and abscisic acid metabolism, low temperature and salt responsive protein and low temperature-induced transcription factors(CBF and WRKY). Furthermore, 102 circRNAs were found to act as the corresponding 24 miRNAs sponges in tomato. These discoveries deciphered the unexpected complexity of the regulatory circRNAs and may open a window for understanding the functions of circRNAs in plants.

High­oxygen-modified atmospheric packaging delays flavor and quality deterioration in fresh-cut broccoli.

The purpose of this study was to investigate the impact of high­oxygen-modified atmospheric packaging (HOMAP) on aroma changes in fresh-cut broccoli during storage and to explore its regulatory mechanisms. The results showed that HOMAP reduced the levels of undesirable aroma substances hexanoic acid, isobutyric acid, cyclopentanone and increased glucosinolate accumulation by inhibiting the expression of arogenate/prephenate dehydratase (ADT), bifunctional aspartate aminotransferase and glutamate/aspartate-prephenate aminotransferase (PAT), thiosulfate/3-mercaptopyruvate Transferase (TST) to reduce the odor of fresh-cut broccoli. HOMAP inhibited the expression of respiratory metabolism related genes 6-phosphate fructokinase 1 (PFK), pyruvate kinase (PK), and NADH-ubiquinone oxidoreductase chain 6 (ND6). In HOMAP group, the low expression of phospholipase C (PLC), phospholipase A1 (PLA1), linoleate 9S-lipoxygenase 1 (LOX1) related to lipid metabolism and the high expression of naringenin 3-dioxygenase (F3H), trans-4-Hydroxycinnamate (C4H), glutaredoxin 3 (GRX3), and thioredoxin 1 (TrX1) in the antioxidant system maintained membrane stability while reducing the occurrence of membrane lipid peroxidation.

The mechanism by which oriented polypropylene packaging alleviates postharvest 'Black Spot' in radish root (Raphanus sativus).

INTRODUCTION: The postharvest physiological disorder known as 'black spot' in radish roots (Raphanus sativus) poses a significant challenge to quality maintenance during storage, particularly under summer conditions. The cause of this disorder, however, is poorly understood. OBJECTIVES: Characterize the underlying causes of 'black spot' disorder in radish roots and identify strategies to delay its onset. METHODS: Radish roots were placed in either polyvinyl chloride (PVC) or oriented polypropylene (OPP) packaging and stored for 4 days at 30 °C. Appearance and physiological parameters were assessed and transcriptomic and metabolomic analyses were conducted to identify the key molecular and biochemical factors contributing to the disorder and strategies for delaying its onset and development. RESULTS: OPP packaging effectively delayed the onset of 'black spot' in radishes, potentially due to changes in phenolic and lipid metabolism. Regarding phenolic metabolism, POD and PPO activity decreased, RsCCR and RsPOD expression was downregulated, genes involved in phenols and flavonoids synthesis were upregulated and their content increased, preventing the oxidative browning of phenols and generally enhancing stress tolerance. Regarding lipid metabolism, the level of alpha-linolenic acid increased, and genes regulating cutin and wax synthesis were upregulated. Notably, high flavonoid and low ROS levels collectively inhibited RsPLA2G expression, which reduced the production of arachidonic acid, pro-inflammatory compounds (LTA4 and PGG2), and ROS, alleviating the inflammatory response and oxidative stress in radish epidermal tissues. CONCLUSION: PVC packaging enhanced the postharvest onset of 'black spot' in radishes, while OPP packaging delayed both its onset and development. Our study provides insights into the response of radishes to different packaging materials during storage, and the causes and host responses that either enhance or delay 'black spot' disorder onset. Further studies will be conducted to confirm the molecular and biochemical processes responsible for the onset and development of 'black spot' in radishes.

Ectoine maintains the flavor and nutritional quality of broccoli during postharvest storage.

The bacterial derived osmolyte ectoine has been shown to stabilize cell structure and function, a property that may help to extend the shelf life of broccoli. The impact of ectoine on broccoli stored for 4 d at 20 °C and 90% relative humidity was investigated. Results indicated that 0.20% ectoine treatment maintained the quality of broccoli, by reducing rate of respiration and ethylene generation, while increasing the levels of total phenolics, flavonoids, TSS, soluble protein, and vitamin C, relative to control. Headspace-gas chromatography-mass spectrometry, transcriptomic and metabolomic analyses revealed that ectoine stabilized aroma components in broccoli by maintaining level of volatile compounds and altered the expression of genes and metabolites associated with sulfur metabolism, as well as fatty acid and amino acid biosynthesis pathways. These findings provide a greater insight into how ectoine preserves the flavor and nutritional quality of broccoli, thus, extending its shelf life.