Search Results (234)

Postharvest storage of kiwifruit requires the implementation of precise environmental conditions to maintain fruit quality and reduce decay. In this research, conducted over two years, we examined whether the storage conditions, characterized by low temperature (1 ± 1 °C) and ultra-high relative humidity (higher than 99%, close to saturation), generated by the Xedavap^® machine from Xeda International, were effective in maintaining the fruit quality and reducing postharvest rots compared to standard storage conditions, characterized by involved low temperature (1 ± 1 °C) and high relative humidity (98%). Kiwifruits preserved under the experimental conditions exhibited a significantly lower rot incidence after 60 days of storage, with the treated fruits showing 4.48% rot compared to 23.03% under the standard conditions in the first year, using inoculated fruits, and 6.30% versus 9.20% in the second year using naturally infected fruits, respectively. After shelf life (second year only), rot incidence remained significantly lower in the treated fruits (12.80%) compared to the control (42.30%). Additionally, quality analyses showed better parameters when using the Xedavap^® system over standard methods. The ripening process was effectively slowed down, as indicated by changes in the total soluble solids, firmness, and titratable acidity compared to the control. These results highlight the potential of ultra-high relative humidity conditions to reduce postharvest rot, extend the shelf life, and enhance the marketability of kiwifruit, presenting a promising and innovative solution for the horticultural industry. Full article

Chilling injury (CI) frequently occurs in postharvest flat peach fruit during cold storage, leading to quality deterioration and a reduced shelf life. Therefore, investigating the key factors involved in alleviating CI and developing effective preservatives are vital scientific issues for the industry. 2,4-Epibrassinolide (EBR) is a crucial endogenous hormone involved in plant response to both biological and environmental stressors. At present, most studies focus on the mechanisms of mitigating CI using a single concentration of EBR treatment, while few studies focus on the effects varying EBR concentrations have on CI. The purpose of this research is to explore the effects of varying concentrations of EBR on the postharvest quality and cold resistance of peach fruit, thereby establishing a basis for refining a technical framework of environmentally sustainable strategies to mitigate postharvest CI. The results show that EBR treatment effectively inhibits the generation of reactive oxygen species (ROS) and malondialdehyde (MDA) by maintaining the activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), thereby delaying the internal browning process of postharvest peaches. In addition, EBR treatment reduced the consumption of total phenolics by inhibiting the activities of polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL). Experimental results identify that 5 μmol L⁻¹ EBR treatment emerged as the most effective concentration for maintaining core postharvest quality attributes. It significantly delayed the decrease in firmness, reduced weight loss, effectively inhibited the production of H₂O₂ and O₂⁻·, particularly during the early storage period, strongly restrained the activity of PAL, and maintained lower rot rates and internal browning indexes. While the 15 μmol L⁻¹ EBR treatment enhanced antioxidant activity, increased total phenolic content at certain stages, and maintained higher soluble solids and acid content, its effects on key physical quality parameters, like firmness and weight loss, were less pronounced compared to the 5 μmol L⁻¹ treatment. Full article

Penicillium astrolabium is a primary pathogenic fungus that causes grape blue mold during postharvest, leading to substantial losses in the grape industry. Nevertheless, hypovirulence-associated mycoviruses can attenuate the virulence of postharvest grape-rot pathogens, thereby offering a promising biocontrol tool. Characterizing the mycovirus repertoire of P. astrolabium is imperative for grape protection, yet remains largely unexplored. Here, we screened six strains harboring viruses in 13 P. astrolabium isolates from rotted grapes. Using high-throughput sequencing, four novel dsRNA viruses and two +ssRNA viruses were identified from the six P. astrolabium strains. The dsRNA viruses belonged to two families—Chrysoviridae and Partitiviridae—and were designated to Penicillium astrolabium chrysovirus 1 (PaCV1), Penicillum astrolabium partitivirus 1′ (PaPV1′), Penicillum astrolabium partitivirus 2 (PaPV2), and Penicillum astrolabium partitivirus 3 (PaPV3). For the +ssRNA viruses, one was clustered into the Alphaflexiviridae family, while the other one was clustered into the Narnaviridae family. The two +ssRNA viruses were named Penicillium astrolabium alphaflexivirus 1 (PaAFV1) and Penicillium astrolabium narnavirus 1 (PaNV1), respectively. Moreover, several viral genomic contigs with non-overlapping and discontinuous sequences were identified in this study, which were probably representatives of five viruses from four families, including Discoviridae, Peribunyaviridae, Botourmiaviridae, and Picobirnaviridae. Taken together, our findings could expand the diversity of mycoviruses, advance the understanding of mycovirus evolution in P. astrolabium, and provide both potential biocontrol resources and a research system for dissecting virus–fungus–plant interactions. Full article

Culinary melon (Cucumis melo subsp. agrestis var. conomon) is widely cultivated throughout Thailand and represents an important agricultural crop. During 2023–2024, anthracnose, charcoal rot, and fruit rot caused by fungi were observed on postharvest culinary melon fruits in northern Thailand. This study aimed to isolate and identify fungal pathogens associated with these postharvest diseases in culinary melons, as well as to assess their pathogenicity. Eight fungal strains were isolated and identified through morphological characterization and multi-gene phylogenetic analysis. Colletotrichum chlorophyti and C. siamense were identified as the causal agents of anthracnose, Fusarium sulawesiense caused fruit rot, and Macrophomina phaseolina was responsible for charcoal rot. Pathogenicity tests were conducted, and the fungi were successfully re-isolated from the symptomatic lesions. Moreover, sensitivity tests for fungicides revealed that C. siamense was completely inhibited by copper oxychloride and copper hydroxide. Colletotrichum chlorophyti was inhibited by benalaxyl-M + mancozeb, copper hydroxide, and mancozeb. In the case of M. phaseolina, complete inhibition was observed with the use of benalaxyl-M + mancozeb, mancozeb, and propineb. Copper hydroxide successfully inhibited F. sulawesiense completely. To our knowledge, this study is the first to report C. siamense and C. chlorophyti as causes of anthracnose, F. sulawesiense as a cause of fruit rot, and M. phaseolina as a cause of charcoal rot in postharvest culinary melon fruits in Thailand. It also marks the first global report of C. siamense, M. phaseolina, and F. sulawesiense as causal agents of these respective diseases in culinary melon. Furthermore, the results of the fungicide sensitivity tests provide valuable information for developing effective management strategies to control these postharvest diseases in the future. Full article

Several species of Fusarium are reported to infect inflorescences of high-THC-containing cannabis (Cannabis sativa L.) plants grown in greenhouses in Canada. These include F. graminearum, F. sporotrichiodes, F. proliferatum, and, to a lesser extent, F. oxysporum and F. solani. The greatest concern surrounding the infection of cannabis by these Fusarium species, which cause symptoms of bud rot, is the potential for the accumulation of mycotoxins that may go undetected. In the present study, both naturally infected and artificially infected inflorescence tissues were tested for the presence of fungal-derived toxins using HPLC-MS/MS analysis. Naturally infected cannabis tissues were confirmed to be infected by both F. avenaceum and F. graminearum using PCR. Pure cultures of these two species and F. sporotrichiodes were inoculated onto detached inflorescences of two cannabis genotypes, and after 7 days, they were dried and assayed for mycotoxin presence. In these assays, all Fusarium species grew prolifically over the tissue surface. Tissues infected by F. graminearum contained 3-acetyl DON, DON, and zearalenone in the ranges of 0.13–0.40, 1.18–1.91, and 31.8 to 56.2 μg/g, respectively, depending on the cannabis genotype. In F. sporotrichiodes-infected samples, HT2 and T2 mycotoxins were present at 13.9 and 10.9 μg/g in one genotype and were lower in the other. In F. avenaceum-inoculated tissues, the mycotoxins enniatin A, enniatin A1, enniatin B, and enniatin B1 were produced at varying concentrations, depending on the isolate and cannabis genotype. Unexpectedly, these tissues also contained detectable levels of 3-acetyl DON, DON, and zearalenone, which was attributed to apre-existing natural infection by F. graminearum that was confirmed by RT-qPCR. Beauvericin was detected in tissues infected by F. avenaceum and F. sporotrichiodes, but not by F. graminearum. Naturally infected, dried inflorescences from which F. avenaceum was recovered contained beauvericin, enniatin A1, enniatin B, and enniatin B1 as expected. Uninoculated cannabis inflorescences were free of mycotoxins except for culmorin at 0.348 μg/g, reflecting pre-existing infection by F. graminearum. The mycotoxin levels were markedly different between the two cannabis genotypes, despite comparable mycelial colonization. Tall fescue plants growing in the vicinity of the greenhouse were shown to harbor F. avenaceum and F. graminearum, suggesting a likely external source of inoculum. Isolates of both species from tall fescue produced mycotoxins when inoculated onto cannabis inflorescences. These findings demonstrate that infection by F. graminearum and F. avenaceum, either from artificial inoculation or natural inoculum originating from tall fescue plants, can lead to mycotoxin accumulation in cannabis inflorescences. However, extensive mycelial colonization following prolonged incubation of infected tissues under high humidity conditions is required. Inoculations with Penicillium citrinum and Aspergillus ochraceus under these conditions produced no detectable mycotoxins. The mycotoxins alternariol and tentoxin were detected in several inflorescence samples, likely as a result of natural infection by Alternaria spp. Fusarium avenaceum is reported to infect cannabis inflorescences for the first time and produces mycotoxins in diseased tissues. Full article

Essential oils (EOs) are widely recognized for their antifungal properties, but their efficacy against specific phytopathogenic fungi associated with banana (Musa paradisiaca) rot remains underexplored. This study aimed to evaluate the antifungal potential of EOs from Origanum vulgare, Salvia rosmarinus, Syzygium aromaticum, Thymus vulgaris, Cinnamomum verum, and Ocimum basilicum against five fungal species isolated from infected banana peels. Fungal isolates were obtained using PDA medium supplemented with chloramphenicol and were purified by weekly subculturing. Morphological and microscopic characterization was complemented by molecular identification based on ITS sequencing and phylogenetic reconstruction using Neighbor-Joining and UPGMA methods in MEGA v11. In vitro and ex vivo antifungal assays were performed at EO concentrations ranging from 200 to 1000 ppm. Thyme oil exhibited the strongest inhibitory effect, with complete growth suppression at 1000 ppm. Cinnamon and oregano also demonstrated effective inhibition at 600 ppm, while clove, rosemary, and basil were markedly less effective. Statistical analysis confirmed significant effects of EO type and concentration on fungal growth (p < 0.001). Molecular results showed strong phylogenetic support for isolate identification, with bootstrap values above 93% in most clades. These findings support the selective use of specific EOs as sustainable alternatives to synthetic fungicides in the postharvest management of banana diseases and provide a molecularly supported basis for their targeted application in integrated control strategies. Full article

Rhizopus stolonifer causes soft rot disease in strawberry and is considered one of the most destructive pathogens affecting strawberries worldwide. This study investigated the efficacy of three atmospheric non-thermal plasmas (NTPs) consisting of gliding arc (GA), Tesla coil (TC) and dielectric barrier discharge (DBD) for controlling R. stolonifer infection. Fungal mycelial discs were exposed to these plasmas for 10, 15 or 20 min, whereas conidial suspensions were treated for 1, 3, 5 or 7 min. Morphological alterations following non-thermal plasma exposure were studied using scanning electron microscopy (SEM). Exposure to GA and DBD plasmas for 20 min completely inhibited mycelial growth. SEM analysis revealed significant structural damage to the mycelium, sporangia and sporangiospores of treated samples compared to untreated controls. Complete inhibition of sporangiospore germination was achieved with treatments for at least 3 min for all NTPs. Pathogenicity assays on strawberry fruit showed that 15 min exposure to any of the tested NTPs completely prevented the development of soft rot disease. Importantly, NTP treatments did not adversely affect the external or internal characteristics of treated strawberries. These findings suggest that atmospheric non-thermal plasmas offer an effective approach for controlling R. stolonifer infection in strawberries, potentially providing a non-chemical alternative for post-harvest disease management. Full article

Potatoes are highly sensitive to drought, particularly during tuber initiation. This study aimed to evaluate the effectiveness of film-forming (Vapor Gard [VG]) and metabolic (abscisic acid [ABA]) antitranspirants in mitigating drought stress and reducing tuber physiological disorders in four potato varieties. Two experiments examined the effects of VG and ABA antitranspirants on drought-stressed potato plants of four varieties (Challenger, Markies, Nectar, and Russet Burbank) grown in pots in a polytunnel (semi-controlled environment). Experiment 1 imposed severe drought by withholding irrigation until 70% of the available water content was depleted (reaching 15–17% volumetric water content within ~15 days), while Experiment 2 featured gradual drought stress from tuber initiation, with the soil volumetric water content declining to <10% over 30 days. Antitranspirants were applied at the start of the tuber initiation and two weeks later to assess their impact on the soil volumetric water content, stomatal conductance, relative water content, yield, and tuber physiological disorders. Drought significantly reduced the soil and plant water status, tuber yield, and quality across both experiments, with more severe effects observed in Experiment 1. VG and ABA had repeatable effects in both experiments and in all varieties, reducing water stress by preventing a large reduction in the relative water content during the tuber initiation and bulking stages. Both antitranspirants improved the tuber appearance by reducing the tuber skin disorder of russeting in the susceptible Challenger variety in both experiments, with VG being more effective than ABA. Beneficial reductions in the effects of drought from antitranspirants were also recorded in the volumetric water content, stomatal conductance, yield, and jelly end rot but not consistently in all varieties and in both experiments. The results show that antitranspirants have the potential to minimise water stress in droughted potatoes and subsequently reduce the physiological disorder of russeting and improve the tuber appearance of the Challenger variety. Full article

Peach fruit faces severe postharvest losses due to thin epidermis and susceptibility to Rhizopus stolonifer-induced soft rot. Chemical control risks residue and resistance issues, demanding eco-friendly alternatives. This study elucidated the mechanism by which trans-2-hexenal (E2H) mitigated postharvest soft rot caused by Rhizopus stolonifer in peach (Prunus persica cv. Hujing Milu) fruit. The results demonstrated that E2H treatment significantly delayed lesion expansion by 44.7% and disease incidence by 23.9% while effectively maintaining fruit quality by delaying firmness loss, reducing juice leakage, and suppressing malondialdehyde (MDA) accumulation. E2H treatment upregulated phenylpropanoid pathway gene expression, enhancing key phenylpropanoid metabolism enzymes activities (phenylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase (C4H), 4-coumarate-CoA ligase (4CL), polyphenol oxidase (PPO), peroxidase (POD)), leading to the increase of total phenolics by 7.9%. E2H treatment analysis revealed significant enhancements in both chitinolytic activity (CHI) and β-1,3-glucanase (GLU) activity by 85.7% and 12.9%, indicating potentiation of the enzymatic defense system. Concurrently, E2H treatment could improve the redox modulation capacity of peach fruits through promoting catalytic efficiency of redox-regulating enzymes, increasing the accumulation of ascorbic acid (AsA) by 8.1%, inhibiting the synthesis of dehydroascorbic acid (DHA) by 18.6%, as well as suppressing the biosynthesis of reactive oxygen species (ROS). These coordinated enhancements in pathogenesis-related proteins (CHI, GLU), phenylpropanoid metabolism activation, and antioxidant systems are strongly associated with E2H-induced resistance against Rhizopus stolonifer, though contributions from other factors may also be involved. Full article

Avocado, a fruit consumed worldwide and essential for countries like Mexico and Chile, faces significant postharvest challenges, particularly during prolonged storage and transportation periods, where Botryosphaeriaceae and Glomerellaceae genera cause fruit rots that can generate substantial economic losses. This study investigated three Hass avocado orchards in the Valparaíso region of Chile to identify spore dispersion peaks, analyze the aerial dynamics of fungal inoculum, and evaluate the association with climatic conditions, as well as the incidence (I) and damage index (DI) of fruit rots. Spore traps were installed in symptomatic trees and monitored weekly over 13 months. Meteorological data were collected in parallel. Fruits from these orchards were sampled to evaluate postharvest rots, physiological maturity, and disease severity using molecular techniques, including DNA sequencing and phylogenetic analysis of isolated pathogens. The results revealed that spore peaks for both fungal families were closely associated with increased rainfall and high relative humidity, particularly from June to mid-September (winter season). The Santo Domingo orchard exhibited the highest disease pressure, with stem-end rot reaching an I of 44% and a DI of 17.25%, and anthracnose reaching an I of 23% and a DI of 12.25%. This study provides the first long-term, field-based evidence of airborne spore dynamics of Botryosphaeriaceae and Glomerellaceae in Chilean avocado orchards and their statistical relationship with environmental variables. These findings highlight the potential of incorporating climatic indicators—such as rainfall thresholds and humidity levels—into monitoring and early-warning systems to optimize fungicide application timing, reduce unnecessary chemical use, and improve postharvest disease management in avocado production. Full article

The Kponan yam (Dioscorea cayenensis-rotundata) is a culturally and economically important crop in Côte d’Ivoire but faces significant post-harvest losses, reducing farmers’ and traders’ incomes. This study aimed to identify strategies to minimize these losses during storage. To this end, Kponan yams from Bondoukou, Bouna, and Kouassi-Kouassikro, key production areas, were grown in experimental plots and monitored over three months in both field and warehouse storage. The results showed that yams harvested in Kouassi-Kouassikro (2.53 ± 0.06 kg) and Bondoukou (2.37 ± 0.09 kg) were heavier than those from Bouna (2.01 ± 0.11 kg). Storage conditions influenced spoilage: yams stored in pits had lower alteration rates (40.00% to 48.57%) compared to those stored under straw huts or trees (100%). In warehouses, alteration rates ranged from 72.29% (Bondoukou) to 100% (Kouassi-Kouassikro), with rot rates varying from 47.05% to 70.00%, respectively. Weight losses varied from 15.15% to 36.67% in warehouses versus 8.47% to 42.86% in field storage. These results underline the importance of storage methods, with pit storage significantly reducing deterioration. Full article

Botryosphaeriaceae species were recently found to be responsible for heavy mango crop losses worldwide. In 2020, mango fruit samples showing fruit decay symptoms were collected from Glenn, Kent, Irwin, Palmer, Brokaw 2, and Gomera 3 accessions in 4 orchards located in Sicily (Italy). A molecular analysis of the ITS and tub2 regions performed on 41 representative isolates allowed for the identification of mainly Neofusicoccum parvum and occasionally Botryosphaeria dothidea (1/41) as the causal agents of fruit decay. Pathogenicity proofs were satisfied for both fungal pathogens. Ripe and unripe Gomera 3 mango fruits were used to compare the virulence among the N. parvum isolates. Postharvest experiments performed on Gomera 3 fruits and by using different biocontrol agents (BCAs) showed that the performance of treatments in reducing fruit decay depends on N. parvum virulence. The data show that unregistered Wickerhamomyces anomalus WA-2 and Pichia kluyveri PK-3, followed by the trade bioformulate Serenade™ (Bacillus amyloliquefaciens QST713), were the most effective in managing mango fruit rot. This paper shows, for the first time, the potential of different BCAs, including Trichoderma spp., for the controlling of postharvest decay caused by N. parvum on mango fruits. Full article

Citrus rot seriously reduces the quality of citrus, causes economic losses, and is an urgent problem for the citrus industry. Effective preservation and pretreatment methods have an important impact on the maintenance of mandarin orange quality. In this study, mandarin orange was pretreated through single and synergistic treatments with ozone water and morpholine fatty acid salts in order to assess their effects on the fruit’s physicochemical properties. First, the parameters of the ozone water treatment, including time and ozone water concentration, were optimized to determine the optimal pretreatment conditions for the subsequent mandarin orange preservation. Subsequently, the mandarin oranges subjected to different pretreatments (ozone water, morpholine fatty acid salts, ozone water + morpholine fatty acid salts, water, and blank control) were stored at 25 ± 2 °C and 75% relative humidity for 20 d to simulate retail conditions (shelf-life). Finally, the surface microbial content, firmness, weight loss, total soluble solids content, respiration rate, decay rate, and surface morphology of mandarin orange peel were assessed during the storage period. The results showed that the synergistic treatment with ozone water and morpholine fatty acid salts significantly reduced the surface microbial content (Lg CFU/g = 3.91), weight loss (2.79%), decay rate (2.5%), and firmness losses on day 20 compared to other single treatments (p < 0.05). Hence, synergistic treatment with ozone water and morpholine fatty acid salts is a new green mandarin orange preservation technology with promising applications in controlling postharvest diseases and extending the storage period. Full article

This study aimed to investigate the impact of Botrytis cinerea (B. cinerea) on the post-harvest quality of ‘Munage’ grapes and their molecular mechanism. The results showed that B. cinerea significantly reduced the post-harvest quality of ‘Munage’ grapes, which was manifested by an increase in incidence and rot rate, a significant increase in weight loss rate and fruit color difference, and a significant decrease in fruit firmness. In addition, B. cinerea infection significantly changed the reactive oxygen species and antioxidant enzyme activities of ‘Munage’ grapes, including increasing the H₂O₂ content and O₂⁻ generation rate as well as changing the superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), and peroxidase (POD) activities. B. cinerea also significantly changed the wax structure and content of ‘Munage’ grapes, causing the wax to completely dissolve and disappear and reducing the relative content of wax components. Through RNA-seq analysis, it was found that after B. cinerea infection, 49 differentially expressed genes (DEGs) related to fatty acid synthesis, extension, cutin and wax synthesis, and wax transport showed up-regulation or down-regulation, and 12 different transcription factors (TFs) also showed significant differential expression. These TFs were correlated with DEGs related to wax synthesis and metabolism, indicating that they may play an important role in the epidermal wax changes in ‘Munage’ grapes caused by B. cinerea. This study revealed the impact of B. cinerea on the post-harvest quality of ‘Munage’ grapes and their molecular mechanism and provided a scientific basis for grape disease prevention and quality maintenance. Full article

Soft rotting caused by Rhizopus stolonifer is one of the most important postharvest decays in Kokei No. 14 organic sweet potato roots. While various methods have been explored for controlling this pathogen, there remains a need for effective, safe, and applicable alternatives, particularly using essential oils (EOs). This study evaluated the efficacy of EOs, specifically carvacrol, thymol, and thyme oil, in controlling Rhizopus soft rot. We conducted both in vitro and in vivo tests to assess their effects on fungal mycelial growth, spore germination, and the incidence and severity of soft rot in sweet potatoes, along with quality evaluations of the roots. The results indicated that the vapor phase of carvacrol, thymol, and thyme oil was more effective than the contact phase in inhibiting fungal growth and spore germination. In vivo tests revealed that all three EOs significantly reduced the incidence and severity of soft rot, with thymol and thyme oil at 300 mg/L, and carvacrol at 500 mg/L being the most effective. Quality assessments showed minimal impact on properties such as firmness, weight loss, color, starch, carotenoids, and flavonoids, although residual odors increased. GC/MS analysis confirmed that thyme oil contained high levels of both thymol and carvacrol, along with other antimicrobial compounds, suggesting that the cumulative activity of these volatile compounds enhanced their bacteriostatic effects. Thyme oil demonstrated greater efficacy in reducing soft rot development compared to its individual components, making it a promising biofumigant for controlling postharvest diseases in Kokei No. 14 organic sweet potato roots. These findings emphasized the potential for using thyme oil as a safe and effective approach to managing postharvest decay. Full article