Postharvest Fruit Quality Research Articles

Physiological and transcriptomic analysis provide new insights into the mechanisms regulating the maintenance of postharvest quality of goji berry fruit in response to 1-MCP

Physiological and transcriptomic analysis provide new insights into the mechanisms regulating the maintenance of postharvest quality of goji berry fruit in response to 1-MCP

A study on postharvest calcium treatment on chilling injury of tomato fruit

Solanum lycopersicum (tomato) provides a significant amount of vitamins, carotenes, dietary fibres, minerals, and flavonoids, making it a valuable source of nutrients. However, chilling injury (CI) affects tomatoes when the temperature falls below 12°C. Postharvest losses of tomato fruit range from 25% to 42% worldwide, representing losses both in terms of quantity and quality. This study was conducted to evaluate the effectiveness of calcium chloride (CaCl2) treatments on tomato fruit’s CI and the physicochemical quality of postharvest tomato fruit with CaCl2 treatment. Different strengths of CaCl2 (0.5, 2.5, and 4.5% w/v) and control (distilled water) were prepared, and the fruits were soaked for 10 mins as a calcium treatment. Tomato fruits were stored at (5±1°C) prior to the physicochemical analysis; the percentage of chilling injury, surface pitting, weight loss, pH, total soluble sugar (TSS), and concentration of vitamin C was determined at 0, 7, 14, 28 and 42 days of storage. The data significance was analysed by ANOVA test. The result showed that the higher concentration of CaCl2 can significantly decrease (p<0.05) the chilling injury symptom of the tomato fruit for all treatments. The treatment of 4.5% w/v of CaCl2 at days 28 and 42 was found to have a lower CI symptom with (0.66±0.01%) and (1.20±0.01%) respectively. The other physicochemical characteristics were also changed along the treatment of CaCl2.

The effect of ultraviolet-C on the senescence of bitter gourd fruit and the key factors analyzed by transcriptomic and metabolomic analyses

Bitter gourd (Momordica charantia L.) is a tropical and subtropical vegetable that is popular for its rich nutritional content. However, its immature fruit has a short shelf life and spoils easily. This study assessed the effects of ultraviolet-C (UV-C) irradiation on the storage and quality of postharvest bitter gourd fruit. Exposure for 40 s maintained fruit firmness, delayed senescence, increased the antioxidant capacity and minimized damage by reactive oxygen species. Transcriptomic and metabolomic analyses identified 12,733 differentially expressed genes and 282 metabolites during storage. The downregulation of genes for ethylene synthesis and cell wall degradation delayed ripening and senescence, while the upregulation of phenylpropanoid biosynthetic genes enhanced its antioxidant properties. Key transcription factors, such as MYB, bHLH, and bZIP, were implicated in the delayed senescence treatment. This research elucidates the mechanisms of prevention of bitter gourd with UV-C and offers insights into the genetic and metabolite candidates for enhanced strategies of postharvest preservation.

Effect of PVA-based films incorporated with postbiotics, flax seed mucilage and guar gum to enhance the postharvest quality of fig fruits

Eco-friendly antimicrobial bio-composite films (BCF) were produced by using guar gum (GG), flax seed mucilage (FM) and polyvinyl alcohol (PVA), supplemented with cell-free supernatant (CFS) of Lactobacillus plantarum (L. p) and Lactobacillus delbrueckii (L. d) by the solvent casting technique. The BCF was categorized into: PVA, PVA + FM, PVA + GG, PVA + FM + GG, PVA + FM + CFS, PVA + GG + CFS, PVA + FM + GG + CFS. The film's mechanical, morphological, physical, and antimicrobial properties were characterised. The mechanical, and hydrophobic features of the BCF were increased with the incorporation of FM, GG, and these attributes were faintly decreased with the fusion of postbiotics in films. However, BCF with postbiotics exhibited antimicrobial activity and UV barrier and biodegradable traits, while BCF without postbiotics did not show any antimicrobial effect. According to the characterization study the fabricated PVA + FM + GG and PVA + FM + GG + CFS was employed as packaging material for fig fruit to prolong the shelf life. Overall, PVA + FM + GG + CFS-based packed fig fruits has prolonged shelf life of till 12 days.

Effect of Black Soldier Fly Larvae Frass as Organic Fertilizer on Postharvest Quality and Shelf Life of Open-field-grown Tomato (Solanum lycopersicon L.)

Open-field-grown tomatoes in Saudi Arabia are stressed by poor soil fertility because of the low organic matter content, low nutrient availability, and high pH. Thus, high chemical fertilizer inputs are crucial for commercial production; however, they cause economic loss as well as negatively affect environmental sustainability. The use of efficient organic fertilizers would be useful for developing more cost-effective, environmentally friendly, and sustainable agriculture. The current study evaluated the impact of Black soldier fly (Hermetia illucens L.) frass (BSFF) fertilizer applications as organic fertilizer on postharvest fruit quality and shelf life of open-field-grown F1 hybrid ‘Sinag Tala’ tomatoes compared with those grown under control treatment (received recommended doses of chemical fertilizers for tomato production under open field conditions). The experiment was conducted using a randomized complete block design with four replicates. The results showed that the application of BSFF fertilizer, especially at the higher rate (5 ton/ha; BSFF3), improved the overall quality of tomato fruit. The BSFF fertilizer treatments reduced weight loss, maintained higher firmness, antioxidants [vitamin C, total phenol content (TPC) and total flavinoid (TFC)], total soluble solids (TSS), and titratable acidity (TA) contents, and lowered the TSS/TA ratio of fruits during shelf life compared with those of the control. The decay incidence was only detected after 9 days of shelf life and was significantly lower in all the BSFF fertilizer treatments (range, 8.40%-12.05%) than in the control (15.9%). In addition, BSFF fertilizer treatments reduced both disease incidence and severity of gray mold following pathogen inoculation during shelf life compared with those of the control. These results might be attributable to the higher antioxidants content (vitamin C, TPC, and TFC) and higher polyphenol oxidase activity in BSFF-fertilized tomatoes. In conclusion, BSFF fertilizer could be used as a potential eco-friendly alternative to chemical fertilizers to improve tomato fruit quality during shelf life.

A QTL on chromosome 17 identified by Genome-Wide Association Mapping controls postharvest cold tolerance of Cucurbita pepo L.

The worldwide cultivated Cucurbita pepo L. is one of the most diverse species in the plant kingdom. In this study, chilling tolerance over a wide range of cultivars was characterized to discover the allelic variants to improving the postharvest quality of the immature fruit during cold storage. For this purpose, fruits from 126 accessions of worldwide origin have been evaluated for weight loss and chilling injury after 3, 7 and 14 days of cold storage, classifying them into tolerant, partially tolerant, and sensitive accessions. To verify this classification, antioxidant capacity and lipid peroxidation (MDA) of contrasting accessions (tolerant vs. sensitive) were assessed. The antioxidant capacity significantly decreased during cold storage in the sensitive accessions, while it was maintained in tolerant accessions. Additionally, the sensitive accessions presented a higher accumulation of MDA during this period. Finally, a GWAS analysis using GBS data available in CuGenDBv2, combined with weight loss percentage data, led to the identification of a candidate QTL located on chromosome 17 that regulates postharvest cold tolerance in zucchini. The region contains four SNPs whose alternative alleles were significantly associated with lower weight loss percentage and chilling injury indices during cold storage. Two SNPs are located in the 3' UTR region of the gene CpERS1, a gene involved in ethylene perception. The other two SNPs generate missense mutations in the coding region of a Pectin methyl esterase inhibitor gene (CpPMI). The role of this QTL and these variants in chilling tolerance is discussed.

Correction: Alotaibi et al. Preserving Postharvest Quality of Medjool Date Palm Fruits by Edible Oil Emulsions Application. Sustainability 2024, 16, 5528

The authors would like to make the following corrections to the published paper [...]

Melatonin Maintains Postharvest Quality in Fresh Gastrodia elata Tuber by Regulating Antioxidant Ability and Phenylpropanoid and Energy Metabolism During Storage.

Melatonin treatment has been reported to effectively preserve and improve the postharvest quality of fruits and vegetables during storage. This research focused on examining the significance of melatonin on maintaining the quality of fresh Gastrodia elata tubers throughout the storage period. The findings demonstrated that melatonin application effectively reduced the deterioration rate and inhibited the rise in respiratory rate, malondialdehyde content, and weight loss, while slowing down the decline in soluble solid content. Melatonin treatment led to a decrease in hydrogen peroxide production and a rise in non-enzymatic antioxidant concentrations, including ascorbic acid. Furthermore, it boosted both the activity and expression of indispensable antioxidant enzymes, like superoxide dismutase, catalase, and ascorbate peroxidase. Additionally, melatonin treatment promoted the accumulation of total phenols, flavonoids, and lignin in fresh G. elata, while enhancing both the activity and expression of critical enzymes in the phenylpropanoid pathway, including phenylalanine ammonia-lyase, cinnamate-4-hydroxylase, and 4-coumarate-CoA ligase. Moreover, melatonin treatment boosted the activity and expression of energy-associated enzymes including H+-ATPase, succinate dehydrogenase, Ca2+-ATPase, and cytochrome C oxidase, contributing to the improvement of energy levels in fresh G. elata. In summary, melatonin enhances the antioxidant potential and reduces oxidative damage in fresh G. elata by activating reactive oxygen species, phenylpropanoid metabolism, and energy metabolism, thereby maintaining its postharvest quality.

Differential effects of environmental conditions on the commercially important attributes and postharvest quality of pomegranate fruit

Differential effects of environmental conditions on the commercially important attributes and postharvest quality of pomegranate fruit

POST-HARVEST QUALITY IN THE ‘TOMMY ATKINS’ MANGO FOR DIFFERENT HARVEST TIMES

Determining the correct harvest time is essential for maintaining post-harvest fruit quality. The aim of the present study was to investigate the biochemical and physiological effect of three different harvest times on maintaining post-harvest quality in ‘Tommy Atkins’ mangoes from the state of Roraima, sold in markets in the city of Manaus. The treatments consisted of the different harvest times: control, harvested 90 days after anthesis; early harvest, harvested 70 days after anthesis; and late harvest, harvested 105 days after anthesis. At the end of the experimental period, mangoes harvested at 70 DAA were found to have a low carotenoid content, with the pulp unable to reach commercial maturity; the pulp had a high level of firmness, with the highest concentrations of vitamin C and phenolics, and the greatest antioxidant activity. When the mangoes were harvested at 105 DAA, the pulp had the least firmness and a sugar content very close to that of the early-harvested fruit, with lower concentrations of phenolics and vitamin C, and lower antioxidant activity. On the other hand, the fruit harvested at 90 DAA showed adequate physical resistance and acceptable results for sensory quality, functional compounds and antioxidant activity.

Impact analysis of ethylene antagonists, storage environments and storage periods on postharvest physiology of ‘Cripps Pink’ apple fruit

Ethylene management and manipulating storage conditions are crucial elements that impact the postharvest quality of apple fruit. This study demonstrated the optimal approach for preserving the quality of ‘Cripps Pink’ apple fruit during storage by minimizing ethylene production and action, respiration rate, physiological loss of weight (PLW), and textural changes. Ethylene antagonist treatment had the greatest impact on suppressing ethylene and respiration peaks, while storage duration notably influenced fruit firmness and PLW. Fumigation treatment with 1-methylcyclopropene (MCP), 1H-cyclopropabenzene (BC), and 1H-cyclopropa[b]naphthalene (NC) effectively reduced ethylene and respiration peaks. Storage conditions (cold, controlled atmosphere, and photocatalytic oxidation) affected ethylene production and respiration, with ozonized storage showing higher rates. Prolonged storage led to increased PLW, ethylene production, and decreased fruit firmness. The most effective treatment combination for ethylene action antagonism and maintaining fruit quality was MCP treatment in ozonized cold storage for 120 d.

Zinc Oxide Nanoparticles Treatment Maintains the Postharvest Quality of Litchi Fruit by Inducing Antioxidant Capacity.

Pericarp browning and fruit decay severely reduce the postharvest quality of litchi. Improving the antioxidant capacity of the fruit is an effective way to solve these problems. In our study, the appropriate zinc oxide nanoparticles (ZnO NPs) treatment and its mechanism of action on the storability of litchi was investigated. Litchi fruit was soaked in a 100 mg·L-1 ZnO NPs suspension, water, and 500 mg·L-1 prochloraz for 2 min, respectively. The results showed that the ZnO NPs treatment delayed pericarp browning and decay in litchi fruit and was more effective than prochloraz treatment. The ZnO NPs-treated fruit showed significantly increased contents of total anthocyanin, total phenols, and activities of DPPH scavenging, superoxide dismutase, and glutathione peroxidase, as well as the lowest activities of polyphenol oxidase and laccase. ZnO NPs generated hydrogen peroxide and superoxide anion radicals, which were beneficial in slowing down the decay and inducing antioxidant capacity. However, these reactive oxygen species also consumed catalase, peroxidase, glutathione, and glutathione peroxidase. This means that litchi should be treated with an appropriate concentration of ZnO NPs. We concluded that treatment with a 100 mg·L-1 ZnO NPs suspension could induce antioxidant capacity, which is a promising and effective method to maintain the postharvest quality of litchi.

Caffeic acid enhances the postharvest quality by maintaining the nutritional features and improving the aroma volatiles for nectarine fruit

Maintaining the quality of postharvest nectarine fruit is considerably challenging owing to their vigorous metabolism processes. This study explored the effectiveness of the natural preservative caffeic acid in extending the shelf-life and improving the flavor quality of nectarine. The decay rate of caffeic acid-treated fruit was only 40.00 % but 73.33 % in control group at the end of storage. Other results showed that caffeic acid inhibited fruit quality deterioration, reflected in weight loss, peel color, pulp softening, respiration rate, malondialdehyde accumulation and ethylene biosynthesis. Findings might be attributed to increased levels of antioxidant compounds, such as ascorbic acid, simple phenols and flavonoids, which maintained high antioxidant capacity and metal reducing power of fruit cells. Notably, the content of phenolics was maintained at 241.11 mg kg−1 in caffeic acid-treated fruit by 8 d, which was only 138.21 mg kg−1 in control. Importantly, nectarine treated with caffeic acid possessed a suitable sugar-to-acid ratio, imparting the fruit with an excellent taste. Additionally, caffeic acid facilitated the effective release of esters and lactones, especially γ- and δ-decalactone with fruity aroma, and prevented green aroma and alcoholic off-flavor. The level of lactones in caffeic acid-treated fruit reached 126.76 μg kg−1 during mid-storage, giving the fruit an attractive flavor quality, while was only 50.61 μg kg−1 in control. Overall, caffeic acid exhibited the potential to preserve the quality of nectarine, ensuring both nutritional and edible value for fruit.

Roles of Nitric Oxide and Brassinosteroid in Improving Fruit Quality during Postharvest: Potential Regulators?

Most postharvest fruits are highly perishable, which directly impairs fruit taste and causes an economic loss of fresh products. Thus, it is necessary to find effective techniques to alleviate this issue. Recently, nitric oxide (NO) and brassinosteroid (BR) have been developed as postharvest alternatives to improve fruit quality. This work mainly reviews the recent processes of NO and BR in improving fruit quality during postharvest. Exogenous NO or BR treatments delayed fruit senescence, enhanced disease resistance, and alleviated chilling injury in postharvest fruit, and potential physiological and biochemical mechanisms mainly include (1) enhancing antioxidant and defense ability, (2) affecting ethylene biosynthesis, (3) regulating sugar and energy metabolism, (4) mediating plant hormone signaling, and (5) regulating protein S-nitrosylation and DNA methylation. This review concludes the functions and mechanisms of NO and BR in improving postharvest fruit quality. Additionally, a specific finding is the possible crosstalk of applications of NO and BR during postharvest fruit storage, which provides new insights into the applicability of NO and BR for delaying fruit senescence, enhancing disease resistances of fruit, and alleviating chilling injury in postharvest fruit.

Hydrogen-rich water treatment maintains the quality and prolongs the shelf-life of postharvest table grapes by regulating respiratory and energy metabolisms

Background Table grapes suffer from a dramatic deterioration in quality, a reduction in shelf life and commercial value resulting from allivated postharvest respiratory metabolism and excessive energy consumption after harvest. Objective In this study, effects of hydrogen-rich water (HRW) on berry quality, respiratory metabolism, and energy level were investigated by multi concentration gradient tests (0% (control), 20%, 40%, 60%, 80%, and 100%). Methods To achieve this goal, by measuring fruit quality, respiratory metabolism, related enzyme activities, energy status, and other related indicators, to study its impact on postharvest fruit quality and further explore the mechanism of maintaining fruit quality after harvest. Results Compared to the control group, samples treated with HRW exhibited higher fruit firmness, total soluble solids (TSS), and titratable acids (TA), with the most prominent effect observed after treatment with 60% HRW. Compared with the control group, grapes treated with 60% HRW exhibited more effective regulation in the expression of GPI, AOX, SDH1, COX6a, G6DH, 6PGD, NADK, and AGPase gene, which helped maintain normal respiratory metabolism and energy levels in the fruit samples. Conclusions Our results showed that HRW treatment could potentially maintain the quality and prolong the shelf life of postharvest grapes by regulating gene expression and the activity of key enzymes involved in respiratory and energy metabolisms.

Ultrasound as a Physical Elicitor to Improve Texture in Blueberry Fruit: Physiological Indicator and Transcriptomic Analysis.

Ultrasound (US) washing has been verified to improve the quality of postharvest blueberry fruit. However, its physiological and molecular mechanisms remain largely unknown. In the present study, an US with a frequency of 25 kHz and a power density of 400 W for 2 min was performed to investigate its role in impacting the quality of blueberries. The results showed that US washing improved the quality of blueberries, with a higher firmness and lignin content (p < 0.05) than the control. Moreover, US washing inhibited the levels of superoxide radical (O2·-) production rate and hydrogen peroxide (H2O2) content while stimulating the superoxide dismutase (SOD) and catalase (CAT) activities of the blueberry fruit. Transcriptomic analysis screened 163 differentially expressed genes (DEGs), and the key DEGs were mainly enriched in phenylpropanoid biosynthesis, flavonoid biosynthesis, and plant-pathogen interaction pathways. Furthermore, the transcription factors and the structural genes associated with lignin biosynthesis were also identified from the DEGs. More importantly, the correlation analysis revealed that firmness and lignin content were positively correlated with the expression of C4H, COMT1, and POD52 in blueberry fruit, indicating that these genes might be involved in the regulation of US-mediated lignin synthesis. The findings provide new insight into the US-enhanced quality of blueberry fruits.

Production and postharvest quality of sour passion fruit under deficit irrigation strategies and foliar application of ascorbic acid

ABSTRACT The objective this study was to evaluate the effects of foliar application of ascorbic acid – AsA on the production and postharvest quality of sour passion fruit under deficit irrigation strategies. The experimental design was randomised blocks, in a split-plot scheme, with plots consisting of six strategies of irrigation with water deficit, based on crop evapotranspiration – ETc (irrigation with 100% ETc during the entire cycle – S1; irrigation with 50% ETc in the different stages: vegetative – S2; flowering – S3; fruiting – S4; and successively in the vegetative/flowering stages – S5; and vegetative/fruiting stages – S6) and three concentrations of AsA (0, 88.06 and 176.12 mg/L), with three replicates and three plants per plot. Water deficit reduces the production of sour passion fruit, regardless of the phenological stage of the plants without AsA application. Irrigation with water deficit in the flowering stage (50% of crop evapotranspiration) reduces the physical and chemical quality of sour passion fruits. Ascorbic acid in applied levels was effective in alleviating the effects of water deficit on production, with emphasis on the concentration of 176.12 mg/L on the quality of sour passion fruits, in the period from 160 to 220 days after transplanting.

Recent Advancements in Postharvest Fruit Quality and Physiological Mechanism

Recent Advancements in Postharvest Fruit Quality and Physiological Mechanism

CsbHLH6 positively regulates abscisic acid-mediated citrus fruit coloration during postharvest storage

As is well known, postharvest abscisic acid (ABA) treatment of citrus fruits can significantly enhance fruit coloration by promoting the accumulation of carotenoids, however, the underlying molecular mechanism is still unclear. In this study, we further confirmed the effect of ABA treatment in promoting citrus fruit coloration by activating the expression of 4 key carotenoid metabolism genes (CsPSY, CsLCYB, CsHYD, and CsNCED2) during postharvest storage. A novel basic helix-loop-helix (bHLH) transcription factor, CsbHLH6, was identified using the promoters of 3 key ABA-induced carotenoid metabolism genes (CsLCYB, CsHYD, and CsNCED2) by yeast one-hybrid screening. Overexpression of CsbHLH6 enhanced carotenoid accumulation in citrus fruits and calli. Interference with CsbHLH6 expression in citrus calli and fruits indicated that CsbHLH6 was essential for ABA-induced carotenoid biosynthesis and fruit coloration. As a nucleus-localized transcriptional activator, CsbHLH6 directly bound to the promoters of 6 key carotenoid metabolism genes (CsPSY, CsLCYB, CsLCYE, CsHYD, CsZEP, and CsNCED2), subsequently activating their expression in vitro and in vivo. Furthermore, ABA signaling significantly raised CsbHLH6 promoter activity, thus enhancing the regulation of carotenoid accumulation by CsbHLH6. In summary, our study reveals the molecular mechanism by which CsbHLH6 regulates ABA-induced citrus fruit coloration during postharvest storage, which is crucial for improving the postharvest appearance quality of citrus fruits.

A vacuolar invertase gene SlVI modulates sugar metabolism and postharvest fruit quality and stress resistance in tomato

Abstract Sugars act as signaling molecules to modulate various growth processes and enhance plant tolerance to various abiotic and biotic stresses. Moreover, sugars contribute to the post-harvest flavor in fleshy fruit crops. To date, the regulation of sugar metabolism and its effect in plant growth, fruit ripening, postharvest quality and stress resistance remains not fully understood. In this study, we investigated the role of tomato gene encoding a vacuolar invertase, hydrolyzing sucrose to glucose and fructose. SlVI is specifically expressed during the tomato fruit ripening process. We found that overexpression of SlVI resulted in increased leaf size and early flowering, while knockout of SlVI led to increased fruit sucrose content, enhanced fruit firmness, and elevated resistance of postharvest fruit to Botrytis cinerea. Moreover, the content of naringenin and total soluble solids was significantly increased in SlVI knockout fruit at postharvest stage. Transcriptome analysis showed a negative feedback regulation triggered by sucrose accumulation in SlVI knockout fruit resulting in a downregulation of BAM3 and AMY2, which are critical for starch degradation. Moreover, genes associated with cell wall, cutin, wax, and flavonoid biosynthesis and pathogen resistance were upregulated in SlVI knockout fruit. Conversely, the expression levels of genes involved in cell wall degradation were decreased in knockout fruit. These results are consistent with the enhanced postharvest quality and resistance. Our findings not only provide new insights into the relationship between tomato fruit sucrose content and postharvest fruit quality, but also suggest new strategies to enhance fruit quality and extend postharvest shelf life.