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• Grafting boosts cucumber yield and quality, including size, weight, and taste. • Grafted plants show better photosynthesis, water efficiency, and performance. • Grafting increases tolerance to soil diseases like nematodes and Fusarium wilt. This study investigates the effects of grafting cucumber scions '189′ and 'Jad' onto three rootstocks: 'Shintoza,' 'Shintoza Suprem,' and 'Strongtoza' with a focus on yield, yield components, fruit quality, physiological performance, vigor, and disease tolerance. Grafting significantly enhanced overall yield and yield components, including fruit number, size, and weight, compared to self-rooted plants. Fruit quality, in terms of texture, firmness, and taste, improved with grafting, and grafted plants exhibited greater uniformity in fruit size and shape. Physiologically, grafted plants demonstrated higher photosynthetic rates, improved stomatal conductance, and better water use efficiency, contributing to increased plant vigor. Among the rootstocks, 'Shintoza Suprem' often led to the most robust growth. Furthermore, grafting conferred enhanced tolerance to soil-borne diseases such as nematodes and Fusarium wilt. Despite a general increase in infection rates during the second growing season, grafted plants maintained superior disease tolerance compared to self-rooted plants. These findings underscore the benefits of grafting in cucumber cultivation, recommending its practice for improved productivity and disease management. [ABSTRACT FROM AUTHOR]

• CMV 2b protein interacts with Cs GRP. • Cs GRP belongs to class II of GRPs. • Cs GRP is localized in cell wall while CMV 2b in the cytoplasm and nucleus. • CsGRP gene is regulated during CMV infection. • Cs GRP play an important role against CMV infection. The development of plant stress tolerance is critical in agriculture and horticulture. During viral infection (biotic stress), various plant host factors engage in interactions with viral proteins leading to gene expression dynamics, differential complex formation, signaling, and metabolite production and subsequent tolerance/resistance or susceptibility. In this study, we found that during cucumber mosaic virus (CMV) infection in Cucumis sativus , glycine-rich protein (Cs GRP) is associated with the CMV 2b protein. Initially, interaction was identified by screening the cucumber cDNA library using yeast two-hybrid assay in which the 2b protein of the virus was used as bait protein. Subsequently, the interaction was further validated using in planta bimolecular fluorescence complementation (BiFC) and in vivo far western blotting (FWB) assays. In BiFC, the bimolecular complex of Cs GRP and 2b was observed as punctate spots in Nicotiana benthamiana epidermal cells. In the localization and colocalization studies, Cs GRP and the bimolecular complex of the Cs GRP-2b protein were found to be localized in the cell wall region. Phylogenetic analysis and domain architecture studies revealed that the interacting Cs GRP belongs to the class II of GRPs, and are characterized by signal peptide, glycine-rich, and cysteine-rich regions. After CMV infection, the expression of the CsGRP transcript was significantly upregulated at 7 and 14 days post virus inoculation (dpi). These findings shed light on the molecular connections that establish plant-virus interactions and highlight the potential role of Cs GRP in CMV-induced disease development. [ABSTRACT FROM AUTHOR]

Vanadium (V) buildup in soil has raised severe global concerns about food safety and environmental contamination. In recent years, development of nanotechnology has exhibited tremendous potential in enhancing crop quality and yield by reclamation of soils contaminated with heavy metals (HMs). In this study, we investigated the potential of silicone oxide nanoparticles (SiONPs) to mitigate V stress in cucumber plants through the regulation of cellular oxidative repair processes. A greenhouse experiment finding demonstrated that SiONPs supplementation at 150 mg kg−1 considerably increased cucumber plant growth characteristics, such as fresh weight (21.62 %) and dry weight (23.67 %), compared to the V-treated plants. SiONPs supplementation improved photosynthesis and leaf gas exchange metrics, indicating increased photosynthetic efficiency. Furthermore, the supplementation of 150 mg kg−1 SiONPs resulted in heightened levels of antioxidant enzymes, including superoxide dismutase (17.13 %), catalase (45.94 %) ascorbate peroxidase (32.24 %), and peroxidase (61.25 %), which potentially serve a critical function in the scavenging of reactive oxygen species (ROS) and the mitigation of oxidative stress induced by V. The application of SiONPs altered the expressions of genes associated with stress and antioxidant defense as well as significantly inhibited the V deposition in plants. In conclusion, results demonstrated that SiONPs possess considerable promise as a sustainable, ecologically friendly, and non-toxic substitute for mitigating V toxicity in cucumber plants. [Display omitted] • Vanadium (V) stress inhibited the cucumber growth. • Silicon oxide nanoparticles (SiONPs) supplementation reduces V-accumulation and improve plant growth. • SiONPs improves root growth and photosynthesis efficiency under V stress. • SiONPs restricts V-aided oxidative stress and activates the plant defense system. [ABSTRACT FROM AUTHOR]

• ZnO nanoparticles (NPs) were active in inhibiting growth of Fusarium oxysporum. • Plants grown in NPs-amended soil showed improved growth. • NPs caused increased activity of plant defense-related enzymes. • Plants showed enhanced expression of defense-related genes after NPs application. Management of Fusarium wilt, a destructive plant disease, mainly relies on chemicals, but research on novel and eco-friendly methods is needed due to the hazardous effects of chemical pesticides. This study explored the soil application of zinc oxide nanoparticles (ZnONPs) to manage Fusarium wilt disease in cucumber plants. The antifungal activity of ZnONPs against in-vitro growth of Fusarium oxysporum was tested through food poisoning test on the potato dextrose agar medium. The in-vivo potential of NPs for managing Fusarium wilt was checked in pot experiment. In-vitro results confirmed the concentration-dependent in-vitro antifungal activity. The NPs application at 500 µg/ml and 600 µg/ml concentrations showed phytotoxicity and significantly inhibited seed germination and growth of cucumber plants. However, NPs at 300 µg/ml significantly suppressed the pathogenic effects of F. oxysporum on cucumber plants without any phytotoxic effect. The pathogen-inoculated cucumber plants grown in soil amended with NPs showed significantly enhanced growth, lower disease severity, and improved root physiology compared to untreated plants. The plants under NPs treatment showed higher chlorophyll and nitrogen content while decreased membrane permeability and malondialdehyde content. Along with direct antifungal activity, the application of NPs caused an increased expression of defense-related genes and higher activities of defense-related enzymes. These findings verified the efficiency of ZnONPs for suppressing Fusarium wilt disease in cucumber crops, thereby promoting a non-chemical and environmentally friendly approach to controlling Fusarium wilt disease. [ABSTRACT FROM AUTHOR]

• Great progress has been made previously in MicroRNAs-guided gene regulation in plant-parasitic cyst nematodes interactions. Little, however, is known about miRNAs regulation of nematode stress response in Cucumis metuliferus, which is a relative of cultivated cucumber or melon and highly resistant to Meloidogyne incognita. • Five cmu-miR396 precursors were identified and characterized from C. metuliferus. A total of 12 genes were then predicted to be as the potential targets of cmu-miR396 and their function involved in transcription factor, metabolism, signal transduction and stress response. Moreover, three cmu-GRFs genes in roots of C. metuliferus were amplified and confirmed by RT-PCR experimently. The analysis was performed for the phylogeny and subcellular localization of cmu-GRFs protein, and the three transcription factors cmu-GRFs were confirmed as the candidate targets of cmu-miR396 through 5′RLM-RACE assays. • These data laid a foundation for further functional analyses to reveal the roles played by miR396 during the interaction between C. metuliferus and M. incognita. MicroRNAs (miRNAs), a class of non-coding small RNAs, play an important role in biotic and abiotic stresses. Previously, great progress has been made in miRNA-guided gene regulation in plant-parasitic cyst nematodes interactions. However, little is known about miRNAs regulation of nematode stress response in Cucumis metuliferus , which is a relative of cultivated cucumber or melon and highly resistant to the root-knot nematode Meloidogyne incognita. On the basis of our investigation recently, five cmu-miR396 precursors were firstly identified and characterized from C. metuliferus in this study. Subquently, a total of 12 genes were predicted to be as the potential targets of cmu-miR396 and their function involved in transcription factor, metabolism, signal transduction and stress response. Moreover, three cmu-GRFs genes with significant differential expression in roots of C. metuliferus were successfully amplified and confirmed by RT-PCR experimently. Additionally, the analysis was performed for the phylogeny and subcellular localization of cmu-GRFs protein, and the three transcription factors cmu-GRFs were confirmed as the candidate targets of cmu-miR396 through 5′RLM-RACE assays. These data laid a foundation for further functional analyses to reveal the roles played by miR396 during the interaction between C. metuliferus and M. incognita , leading to a better understanding of the mechanisms and underlying regulatory networks of miR396-mediated resistance to M. incognita in C. metuliferus. [ABSTRACT FROM AUTHOR]

[Display omitted] • Extraction of secondary metabolites, nutrients from Posidonia oceanica residue. • Optimization of concentration of aqueous extract from Posidonia oceanica. • Use of aqueous extracts as biostimulant in tomato and cucumber germination assays. • Different toxicity for both extracts in cucumber seeds. • Tomato seeds were more resistant to the salinity induced by the plant extract. Biostimulants are organic compounds from plant sources such as botanical extracts and bioactive substances that promote plant growth, enhance photosynthesis and increase crop quality. The accumulation of detached Posidonia oceanica leaves on coasts of the Mediterranean Sea results in economic problems, due to the rejection of the tourists who frequent the beaches in the summer months. However, it is a plant with high content of secondary metabolites that can be used in sustainable agriculture. In this study we investigated the physicochemical characterization of Posidonia oceanica extracts with three different solutions and their application in tomato and cucumber seeds germination. The results showed that the aqueous extract of Posidonia oceanica had a high concentration of macro and micronutrients, as well as secondary metabolites with bioactive activity. The aqueous extract had a beneficial effect on both leaf and root growth on tomato seeds, specifically, an increase of 76% for the relative root growth and 73% for the germination index was obtained with respect to the control using the sample with the intermediate dilution (POe0.5). In addition, the extracts did not show toxicity to either germination or growth of the tomato plant. As for cucumber seed germination, the improvement was less significant and did result in a phytotoxic effect on both germination and plant growth. The most diluted extract had better results on seed germination. Therefore, the application of aqueous extracts of Posidonia oceanica were suitable to be appropriate for tomato germination and in turn contribute to eliminate the lots of Posidonia oceanica remains recovered in summer months in Mediterranean beaches. [ABSTRACT FROM AUTHOR]

Heat-shock proteins (Hsps) are a family of proteins essential in preserving the vitality and functionality of proteins under stress conditions. Cucumber (Cucumis sativus) is a widely grown plant with high nutritional value and is used as a model organism in many studies. This study employed a genomics, transcriptomics, and metabolomics approach to investigate cucumbers' Hsps against abiotic stress conditions. Bioinformatics methods were used to identify six Hsp families in the cucumber genome and to characterize family members. Transcriptomics data from the Sequence Read Archive (SRA) database was also conducted to select CsHsp genes for further study. Real-time PCR was used to evaluate gene expression levels under different stress conditions, revealing that CssHsp-08 was a vital gene for resistance to stress conditions; including drought, salinity, cold, heat stresses, and ABA application. Gas Chromatography-Mass Spectrometry (GC-MS) analysis of plant extracts revealed that amino acids accumulate in leaves under high temperatures and roots under drought, while sucrose accumulates in both tissues under applied most stress factors. The study provides valuable insights into the structure, organization, evolution, and expression profiles of the Hsp family and contributes to a better understanding of plant stress mechanisms. These findings have important implications for developing crops that can withstand environmental stress conditions better. • Heat Shock Protein Family members in Cucumis sativus genome were identified and characterized with bioinformatics methods. • Real-time PCR indicates increased CssHsp-08 , CsHsp40-70 , CsHsp70-06 gene expression under various stress scenarios. • Stress conditions trigger notable accumulations of amino acids in leaves and sucrose in both cucumber tissues, metabolite analysis shows. • Study provides valuable insights into cucumber heat shock protein family's organization, metabolic, and stress-induced expression profiles. [ABSTRACT FROM AUTHOR]

• Demonstrated the better suitability of F1 hybrid for gynogenesis and induction of haploids for the first time. • Flow cytometer confirms high frequency of induced haploids through gynogenesis. • This study establishes the suitability of polymorphic SSRs in detection of haploids from an F1 hybrid. • Significant heterosis for all important parameter of gynogenesis was recorded across the treatments which is first of kind information in vitro gynogenesis of any plant species. • Higher sucrose concentration and combined pre-treatment with cold and heat shock treatments were very useful for induction of large number of ELS. The present study was undertaken to develop an efficient protocol in cucumber for induction of large number haploids through gynogenesis and to understand the effects of heterosis on gynogenesis. One natural variant, DC-48 with exceptionally high shelf life along with another genotype, DC-83 with very low shelf-life and the F 1 hybrid using these contrasting parents were used donor mother plants for in vitro gynogenesis. Effects of developmental stages, plant hormones, sucrose concentration and combined cold and heat shock pre-treatment were studied. For the first time, we are reporting significant heterosis for important parameters of gynogenesis using a F 1 hybrid and their corresponding parental lines as donor genotypes. Unpollinated ovules cultured at one day prior to anthesis was most suitable developmental stage for efficient induction of embryo like structures (ELS) and haploids. Basal MS based media supplemented with 5.0 mg/L Zeatin and 0.2 mg/L NAA was most effective in induction of large number of ELS in all three genotypes. A combination of low temperature pre-treatment and high temperature heat shock treatment after culture was very useful in formation of ELS. Cold pre-treatment at 9 °C for 4–6 days followed by heat shock treatment at 32 °C for 2–4 days were ideal temperature shock treatment for high frequency direct regeneration. A large set of polymorphic and uniformly distributed SSRs were used to confirm hybridity and allelic distribution of the developed plants through gynogenesis using F 1 hybris as mother plant. The ploidy level determined through flow cytometer validated the SSR based detection of ploidy level. This novel approach was suitable in identifying the plants developed from female gametocytes. It was interesting that all the regeneration related traits exhibited significant heterosis in desirable direction across the treatments suggesting the role of heterosis in gynogenesis of cucumber. The findings of the study will facilitate development of large number haploids and doubled haploids for genetic studies and understanding the shelf-life in cucumber. Besides, this study will be instrumental to investigate the metabolic processes and organogenetic changes associated with high frequency regeneration and induction of haploids in response to combined cold and heat treatment and higher concentration of carbohydrate. [ABSTRACT FROM AUTHOR]

Trypsin has a new activity of scavenging superoxide anion and generating hydrogen peroxide. Trypsin can significantly improve the storage quality of C. sativus. To illustrate the mechanism of trypsin-induced resistance in fruits and vegetables, an integrated analysis of widely targeted metabolomics and transcriptomics was carried out. Transcriptomic results showed that 1068 genes highly related to phenylpropanoid biosynthesis gathered in the brown module were obtained by WGCNA. In KEGG analysis, differentially expressed genes (DEGs) were also highly enriched in EIP (Environmental Information Processing) pathways "Plant hormone signal transduction (map04075)" and "MAPK signaling pathway-plant (map04016)". Next, 87 genes were identified as the leading edge by GSEA analysis. So far, CsMYC2 was highlighted as a key transcription factor that regulates phenylpropanoid biosynthesis identified by GSEA and WGCNA. Furthermore, the major route of biosynthesis of phenylpropanoid compounds including coumarins, lignins, chlorogenic acid, flavonoids, and derivatives regulated by trypsin was also illustrated by both transcriptomic and metabolomic data. Results of O2PLS showed that CsMYC2 was positively correlated with Rosmarinic acid-3-O-glucoside, Epigallocatechin, Quercetin-3-O-sophoroside (Baimaside), and so on. Correlation between CsMYC2, phenylpropanoid related genes, and metabolites in C. sativus was illustrated by co-expression networks. Roles of CsMYC2 were further checked in C. sativus by VIGS. The results of this study might give new insight into the exploration of the postharvest resistance mechanism of C. sativus induced by trypsin and provide useful information for the subsequent mining of resistance genes in C. sativus. [Display omitted] • CsMYC2 identified as a hub transcription factor responses to trypsin in C. sativus. • Route of phenylpropanoid biosynthesis regulated by CsMYC2 was rewired in C. sativus. • Trypsin induced C. sativus resistance through JA rather than ABA or other hormones. [ABSTRACT FROM AUTHOR]

A novel "turn-on" fluorescent sensor of CeO 2 @MIL-88B was constructed successfully via the facile in-situ strategy. The as-obtained CeO 2 @MIL-88B could be used for effectively detecting the analyte of thiabendazole (TBZ) by luminescence enhancement, which limit of detection (LOD) was as low as 0.294 μM (nearly 10.4 times smaller than that of MIL-88B). The detection behavior for TBZ exhibited the excellent selectivity and anti-interference ability. Systematic explorations were performed to shed light on the underlying mechanism of "turn-on" effect on fluorescence after adding TBZ. Moreover, the CeO 2 @MIL-88B was also employed for the determination of TBZ in the real samples of orange and cucumber. A novel "turn-on" fluorescent sensor of CeO 2 @MIL-88B was fabricated successfully via the facile in-situ strategy. The as-obtained CeO 2 @MIL-88B could effectively detect thiabendazole (TBZ) by luminescence enhancement, and its LOD was as low as 0.294 μM (nearly 10.4 times smaller than the LOD of MIL-88B). The "turn-on" effect on fluorescence after adding TBZ could be attributed to the ACE and PET mechanism. [Display omitted] • A novel "turn-on" fluorescent sensor of CeO 2 @MIL-88B was fabricated successfully via the facile in-situ strategy. • The as-obtained CeO 2 @MIL-88B possessed high sensitivity and selectivity to the analytes of TBZ. • The "turn-on" effect on fluorescence could be attributed to the ACE and PET mechanism. [ABSTRACT FROM AUTHOR]

Root knot nematodes (RKNs) induce hypertrophy and cell proliferation within the vascular cylinders of host plants, leading to the formation of giant cells (GCs) that are enlarged, multinucleate cells with high metabolic activity. These GCs are formed through repeated karyokinesis without cytokinesis and are accompanied by significant changes in cytoskeleton organization. In this study, two microtubule-binding protein genes, CsMAP65-2 and CsMAP65-3 , are upregulated in cucumber roots upon RKNs infection, specifically at 3, 96, and 120 hpi. GUS expression analysis further confirmed the induction of CsMAP65-2 and CsMAP65-3 in both roots and nematode-induced galls. Silencing CsMAP65-2 or CsMAP65-3 using VIGS technology led to a reduction in gall size and number, as well as a decrease in GCs number (24.98% for CsMAP65-2 ; 19.48% for CsMAP65-3) and area (6% for CsMAP65-2 ; 4% for CsMAP65-3), compared to control plants. Furthermore, qRT-PCR analysis revealed upregulation of CsMYC2、CsPR1、CsPAD4 , and CsPDF1 in CsMAP65-2 silenced lines and upregulation of CsFRK1 in CsMAP65-3 silenced lines, while CsJAZ1 was downregulated in both silenced lines. These findings suggest that CsMAP65-2 and CsMAP65-3 are critical for GCs development during RKN infection and provide a foundation for breeding nematode-resistant cucumber varieties. This research also offers insights for developing sustainable nematode management strategies in gourd crop cultivation. • This study focuses on the microtubule-associated protein in cucumber and their role in susceptibility to nematode. [ABSTRACT FROM AUTHOR]

Plant hormones are important regulators of crop growth and production. In this study, an in situ electrochemical sensor was successfully built using flat microelectrodes with horizontally and vertically grown graphene to detect the plant regulator indole-3-acetic acid (IAA) in plants. Vertical and horizontal graphene layers were prepared by electron-assisted hot-filament chemical vapor deposition. Vertical graphene nanosheets were grown on a horizontal graphene layer as sensing electrodes, and a microneedle sensor was assembled by combining Pt and Ti microelectrodes. The vertical/horizontal graphene (VHG) microneedle sensor can rapidly detect IAA levels in various plants in situ over a wide pH range of 4.0–9.0 and concentration range of 1–100 μM, with a minimum detection limit of 0.21 μM (3σ/S). Subsequently, this microneedle sensor was used to determine the IAA content in different tissues of cucumber and cauliflower stems with satisfactory results. The combination of VHG microelectrode arrays and small electrochemical workstations is useful for constructing portable, low-cost, on-site, and fast electrochemical sensing platforms for plant growth monitoring. [Display omitted] • The sensing electrodes were composed of vertically and horizontally grown graphene. • Vertical and horizontal graphene synergistically enhance electrochemical activity. • A needle-type plant sensor was assembled for the on-site detection of indole-3-acetic acid. • This small sensor is suitable for monitoring stems, fruits, and leaves of plants. [ABSTRACT FROM AUTHOR]

This study developed a biodegrading additive based on nanosilica and modified by cellulase enzyme in the presence of citric acid and sodium citrate. The additive was tested as a facilitator for biodegradation of the commercial low-density polyethylene (LDPE) in soil. Enzyme immobilization was confirmed by enzymatic assays. Moreover, additive and nanocomposites were characterized by spectroscopic and microscopic techniques. To assess the role of additive in biodegradation, CO 2 production in soil was measured at 30 °C for 83 days. Biodegraded nanocomposites were cultivated to isolate possible LDPE-biodegrading microorganisms. Ecotoxicity of the studied materials was evaluated on cucumber (Cucumis sativus L.). CO 2 production from LDPE/additive sample was similar to the starch (1055 ± 14 mg and 1078 ± 28 mg, respectively), and higher than pure LDPE (882 ± 34 mg) and LDPE/nanosilica (992 ± 30 mg). Although the presence of LDPE/nanosilica and LDPE/additive led to root length reduction of 24.3 ± 2.3% compared to the control (soil), the accumulation of root biomass was not affected. Furthermore, the nanocomposites did not cause harmful effects on seedling growth. Nine microbial isolates were recovered from biodegraded samples and identified by molecular techniques. It was demonstrated for the first time the LDPE biodegradation potential by four bacterial isolates (Bacillus safensis FO-36b, Lysinibacillus capsici , Bacillus albus N35-10-2 and Bacillus paranthracis Mn5) and two fungal isolates (Cladosporium halotolerans clone EF_526 and Cladosporium sp. MV-2018B isolate MLT-27). Our study sheds light on the biodegradation of commercial LDPE by soil microorganisms using a novel LDPE-biodegrading additive nanocomposite. [Display omitted] • A novel silica-based additive for LDPE biodegradation was successfully developed. • LDPE/additive biodegradation in soil was evidenced by biomineralization. • LDPE/additive and LDPE presented low toxicity to cucumber seeds and plants. • Potential LDPE-biodegrading strains of bacteria and fungi were identified. • This work characterizes LPDE biodegradation using a novel additive in soil. [ABSTRACT FROM AUTHOR]

Lead is a toxic heavy metal, which accumulates in the soil and is readily absorbed by plant roots. The uptake of toxic elements by crops is a serious threat to human health. For this reason, it is important to prevent the incorporation of heavy metals into the food chain. Our previous study showed that foliar application of calcium nitrate reduces the intensity of lead uptake by different plant species. A significant decrease in metal concentration was observed both in the roots and in the shoots of three crops: tomato, cucumber, and flax. The present research investigated the mechanism for limiting lead accumulation in plant tissues. The experiments were conducted on Cucumis sativus L. seedlings, grown in hydroponic conditions. To compare the role of Ca2 + and NO 3 - ions in the restriction of lead uptake three different calcium salts (nitrate, chloride, and formate), and two nitrates (calcium and potassium) were applied foliarly to plants. The results show that Ca(NO 3) 2 is more efficient in decreasing lead accumulation in tissues than other calcium salts which suggests an important role of NO 3 - ions in the process. In addition, the study demonstrated that the exogenous supply of nitrates helps compensate for nitrogen deficiency caused by lead action and supports the mineral balance. The reduction in lead toxicity to plants after foliar application of nitrates may be due to the stimulation of the biosynthesis of nitric oxide – a key molecule responsible for stress response. • The inhibition of oxidative phosphorylation stimulates Pb uptake but not that of Ca. • Foliar nitrate application neutralises the Pb-induced K, Ca, and N deficiency. • Ca(NO 3) 2 is more efficient in decreasing Pb uptake than other Ca salts. • Both Ca2+ and NO 3 - ions are responsible for the limitation of Pb uptake by plants. [ABSTRACT FROM AUTHOR]

It is difficult and costly to obtain large-scale, labeled crop disease data in the field of agriculture. How to use small samples of unlabeled data for feature learning has become an urgent problem that needs to be solved. The emergence of self-supervised contrastive learning methods and self-supervised mask learning methods can solve the problem of missing labels on the training data. However, each of these paradigms comes with its own advantages and drawbacks. At the same time, the features learned by dataset in a single modality are limited, ignoring the correlation with other modal information. Hence, this paper introduced an effective framework for multimodal self-supervised learning, denoted as MMSSL, to address the task of identifying cucumber diseases with small sample sizes. Integrating image self-supervised mask learning, image self-supervised contrastive learning, and multimodal image-text contrastive learning, the model can not only learn disease feature information from different modalities, but also capture global and local disease feature information. Simultaneously, the mask learning branch was enhanced by introducing a prompt learning module based on a cross-attention network. This module aided in approximately locating the masked regions in the image data in advance, facilitating the decoder in making accurate decoding predictions. Experimental results demonstrate that the proposed method achieves a 95% accuracy in cucumber disease identification in the absence of labels. The approach effectively uncovers high-level semantic features within multimodal small-sample cucumber disease data. GradCAM is also employed for visual analysis to further understand the decision-making process of the model in disease identification. In conclusion, the proposed method in this paper is advantageous for enhancing the classification accuracy of small-sample cucumber data in a multimodal, unlabeled context, demonstrating good generalization performance. • Proposed an effective multi-modal cucumber disease pre-training model. • Combining improved mask learning with contrastive learning. • The proposed model achieved satisfactory results in small samples. [ABSTRACT FROM AUTHOR]

Fresh-cut produce is often contaminated with Escherichia coli O157, posing a significant risk to public health. This study investigated the synergistic inactivation effect and underlying mechanism of ultrasound (US) combined with Zanthoxylum schinifolium essential oil nanoemulsion (ZEO-NE) against E. coli O157:H7, and explored its potential application in fresh-cut cucumbers. The results demonstrated that combined treatment of US and ZEO-NE significantly reduced the viable counts of E. coli O157:H7 compared to treatment with US or ZEO-NE alone. In particular, US (20 kHz, 345 W/cm2) + ZEO-NE (1.0 mg/mL) treatment for 12 min achieved an 8.91 log colony-forming units (CFU)/mL reduction in viable counts of E. coli O157:H7. Moreover, biofilm formation assay revealed that US+EO-NE treatment significantly reduced mobility, altered surface properties, and inhibited biofilm formation of E. coli O157:H7 cells compared to single treatments. The synergistic inactivation mechanism of US+ZEO-NE treatment against E. coli O157:H7 was revealed to involve increased cell membrane permeability, resulting in leakage of nucleic acids, proteins, and LDH, AKP, and ATP, disruption of cell membrane integrity, and alterations in membrane potential. Additionally, the US+ZEO-NE treatment induced reactive oxygen species accumulation and disrupted cell morphology, ultimately leading to E. coli O157:H7 cell death. Notably, the US+EO-NE treatment also significantly reduced the E. coli O15:H7 counts in fresh-cut cucumbers compared to single treatments, without adversely affecting the quality and sensory properties of the produce during storage at 4 °C for 12 days. Overall, these findings suggest that US+EO-NE is a promising technique for bacterial inactivation, and holds potential for improving microbial safety in fresh-cut produce. [Display omitted] • Combined US and ZEO-NE had synergistic inactivation effects on Escherichia coli O157:H7; • The inactivation mechanism of combined US and ZEO-NE against E. coli O157:H7 was initially revealed; • US+ZEO-NE can enhanced the cleaning effect of bacterial on fresh cut cucumbers; • US+ZEO-NE effectively maintains the storage quality of fresh cut cucumbers. [ABSTRACT FROM AUTHOR]

In July–August 2022, an outbreak of hepatitis E was reported following a funeral dinner in a village of Yantai, June 2022. The aim of this study was to characterise the outbreak, search for more cases, and investigate the risk factors to help prevent hepatitis E infection in the future. A 1:2 case-control study was used to investigate the suspected causative food, and HEV antibody testing and genetic tracing were performed on clinical and environmental samples, and HEV antibody of 69 healthy people who did not attend the dinner in the same village were tested. A total of 80 people were exposed to this outbreak and 18 (22.5 %, 18/80) had acute infections, which was much higher than the positivity rate of healthy people of the same age group in the village (2.9 %, 2/69). Multifactorial analysis showed that the infection was significantly associated with the consumption of cucumber in sauce (aOR = 4.44, 95%CI = 1.23–16.06). Further investigation revealed that there was a mixing of pots and pans for washing raw pork products with those for cold meals during dish preparation. A whole genome sequence of HEV was obtained from sera of cases and from an environmental sample from the pork supplier's refrigerator. All sequences were typed as HEV-4d. This foodborne outbreak was most likely caused due to a failure in kitchen hygiene to differentiate between raw and cooked pots and pans during dish preparation, resulting in cross-contamination from defrosted pork to cold dishes. Our findings emphasize the importance of education of food hygiene, especially in remote areas. • Failure to differentiate between raw and cooked pots and pans led to HEV outbreak. • HEV-4d whole genome was sequenced in human for the first time. • HEV-4d was collected and completely sequenced in a low-temperature external environment. [ABSTRACT FROM AUTHOR]

• Bacillus velezensis KB21 promotes cucumber growth under optimal inoculation conditions. • B. velezensis KB21 enhances salt tolerance by modulating ion balance and antioxidant defenses. • B. velezensis KB21 upregulates stress-responsive and phytohormone biosynthesis genes. • Whole-genome analysis reveals genes linked to plant growth and stress adaptation. • B. velezensis KB21 shows promise as a biofertilizer for sustainable agricultural practices. This study investigates the genomic and functional traits of Bacillus velezensis KB21, a plant growth–promoting rhizobacterium, and its effects on cucumber (Cucumis sativus) growth and salt stress tolerance. Whole–genome sequencing revealed a 4.12 Mb circular chromosome with 27 rRNA genes, 86 tRNA genes, and 4,015 coding sequences, including those involved in auxin (IAA), gibberellin (GA), and volatile organic compound biosynthesis. Inoculation at optimal concentration (log 5 and log 3 CFU/mL) significantly enhanced cucumber growth, increasing fresh and dry biomass, leaf area, and root colonization. Growth promotion was linked to the enhanced expression of CsSAUR50 and CsGA20ox , which regulate auxin and GA biosynthesis during seed germination. Under salt stress conditions, KB21–treated plants showed improved growth, a favorable Na+/K+ ratio, and increased antioxidant enzyme activities (SOD, POD, and CAT). The treatment upregulated stress–responsive genes, including HKT, NHX , and AQP , and ABA–related genes (CsNCED1 and CsCYP707A1), demonstrating its role in ion homeostasis and ABA–mediated stress adaptation. These findings highlight the potential of B. velezensis KB21 as a sustainable biofertilizer for enhancing plant growth and resilience under abiotic stress conditions [ABSTRACT FROM AUTHOR]

• Evidence that grafting can alleviate the accumulation and improve the Cd tolerance in cucumber. • This regulatory effect was found to be dominated by the type of rootstocks. • The physiological mechanisms of the regulatory effect produced by grafting are increasing the compartmentalization of Cd in cell walls and promoting the conversion of Cd to low-toxicity forms. Currently, greenhouse soil has cadmium (Cd) pollution problems, causing serious Cd accumulation in various crops, including cucumber. Grafting is now widely used in greenhouse cucumber production, but the role and mechanism of grafting in regulating Cd accumulation and tolerance of cucumber merits further investigated. We used popular planted cucumber varieties 'Jinchun No 4' (Cj) and 'Lvguan' (Cl) as scions and the pumpkin varieties 'Yemu Yixiong' (Py) and 'Jingangzuan F1' (Pj), which are characterized by strong tolerance, weak absorption and low transport capacity of Cd, as rootstocks, to investigate the effect of grafting on Cd tolerance and accumulation in cucumber and its mechanism. Compared with self-rooted cucumber, cucumber grafted onto Py and Pj rootstocks exhibited significantly reduced Cd concentrations in scions and fruits, with improved biomass and fruit quality. There was a slight reduction in Cd concentrations in scions after self-grafting compared to self-rooted cucumber, and this reduction was more significant when Pj was the rootstock. Thus, the reduction effect of grafting was mainly dominated by rootstock effects. Grafting significantly increased the proportions of cell wall Cd, pectate- and protein-bound Cd (FNaCl), and undissolved phosphate-sequestrated Cd (FHAc) of cucumber, whereas it decreased the proportions of Cd in the soluble fractions and organelles as well as inorganic (FE) and water-soluble (FW) Cd. Therefore, grafting cucumber onto 'Jingangzuan F1' and 'Yemu Yixiong' alleviated Cd accumulation and improved Cd tolerance of cucumber by increasing compartmentalization of Cd in cell walls and promoting conversion of Cd to low-toxicity forms. [ABSTRACT FROM AUTHOR]

• Metabolome sequencing was combined with corresponding transcriptome analysis. • 16 differentially expressed genes and three differential metabolites, including sucrose, stachyose, and trehalose, were identified. • Csa_5G322500 may play a crucial role in regulating the soluble sugar content of cucumber fruits. Soluble sugar content is a crucial parameter affecting the taste and flavor of cucumber. Fruit sweetness varies depending on the soluble sugar content. To explore the regulatory mechanism underlying soluble sugar content, we performed metabolome sequencing on diploid (low soluble sugar, CK) and autotetraploid (high soluble sugar, T) cucumber fruits on the day of flowering (S1) and 9 days after flowering (S2). Metabolome sequencing was combined with corresponding transcriptome analysis. In total, 250 and 387 differential metabolites were screened at S1 (T_S1 vs CK_S1) and S2 (T_S2 vs CK_S2), respectively. The combined analysis unveiled that the differentially expressed genes were primarily concentrated in the pathways of starch and sucrose metabolism and galactose metabolism, among others. Overall, 16 differentially expressed genes and three differential metabolites, including sucrose, stachyose, and trehalose, were identified. Csa_5G322500 expressed abundantly and in large differential multiples, as evident from the transcriptome data of diploid and tetraploid cucumber fruits at different developmental stages, indicating that Csa_5G322500 may be the key gene affecting the soluble sugar content of fruits. Agrobacterium -mediated transformation of the plants with Csa_5G322500 revealed significant increases in the soluble sugar content of cucumber at 24, 36, and 48 h after Agrobacterium infection and a significant increase in the expression of Csa_5G322500 at 36 and 48 h after infection. In conclusion, Csa_5G322500 is potentially involved in regulating the soluble sugar content regulation in cucumber fruits. [ABSTRACT FROM AUTHOR]

Ammonium (NH 4 +) enhances plant defense mechanisms but can be phytotoxic as the sole nitrogen source. To investigate the impact of a balanced NH 4 + and NO 3 − ratio on plant defense parameters without adverse effects, cucumber plants (Cucumis sativus L.) were grown under control (14 mM NO 3 − + 2 mM NH 4 +) and elevated level of NH 4 + (eNH 4 +, 8 mM NO 3 −+ 8 mM NH 4 +). Plants subjected to eNH 4 + showed significantly increased shoot and root biomass by about 41% and 47%, respectively. Among the antioxidant enzymes studied, ascorbate peroxidase (EC 1.11.1.11) activity was increased up to 3.3 fold in eNH 4 + compared with control plants, which was associated with enhanced resistance to paraquat. Upregulation of PATHOGENESIS RELATED PROTEIN 4 (PR4) and LIPOXYGENASE 1 (LOX1), accompanied by increased concentrations of salicylic acid and nitric oxide, conferred more excellent resistance of eNH 4 + plants to powdery mildew infection. However, the expression levels of ACC OXIDASE 1 (ACO1) and RESPIRATORY BURST OXIDASE HOMOLOGS B (RBOHB) were lower in eNH 4 + plants, which was consistent with decreased NADPH oxidase activity and lower leaf H 2 O 2 levels. The biosynthesis of phenolics was enhanced, whereas the activities of polymerizing enzymes and lignin deposition were reduced by half in eNH 4 + plants. Besides, a significant effect on plant biomass under salt or drought stress has not been observed between control and eNH 4 + plants. These results showed that different defense pathways are distinctively affected by eNH 4 + treatment, and the NH 4 + to NO 3 − ratio may play a role in fine-tuning the plant defense response. • The effect of elevated level of NH 4 + (eNH 4 +) (8 mM NH 4 + + 8 mM NO 3 −) was studied. • Biomass of eNH 4 + plants was improved under control but not under abiotic stresses. • The levels of nitric oxide and salicylic acid were higher in eNH 4 + plants. • Expression of PR4 and LOX1 was increased while ACO1 and RBOHB were downregulated. • ENH 4 + plants showed higher resistance to paraquat and powdery mildew infection. [ABSTRACT FROM AUTHOR]

Quantitative analysis for plant growth attributes has gained prominence in plant science and agriculture. Despite the availability of automated phenotyping systems as a solution to labor-intensive manual measurement techniques, these systems often require specialized knowledge and face challenges in scaling for high-throughput applications. This research introduces a scalable high-throughput plant phenotyping technique utilizing a Pan Tilt Zoom (PTZ) camera. The primary objective is to assess the application of a PTZ camera in a plant phenotyping system. By integrating open-source software and hardware technologies, the method captures images of cucumber plants in a controlled greenhouse environment. The operational procedure of the robot consists of a series of steps. It begins with the robot's initial movement to capture infrared images, followed by an analysis to detect Aruco markers serving as location identifiers for capturing plant images. Subsequently, the PTZ camera is adjusted to capture specific plant traits from predefined viewpoints. The captured images with location IDs, preset viewpoints, and timestamps are then sent to a remote server. Validation of the system's dependability includes manual measurements on fundamental operations and the evaluation of the effectiveness of zoomed images captured by the PTZ camera, tested through plant feature detection. Experimental results demonstrate promising outcomes, achieving a mean average precision (mAP) of 94%, 97.6%, 98.4%, 90.1%, and 97.6% for apical buds, male flowers, female flowers, tiny cucumbers, and mature cucumbers respectively when using the trained YOLOv8s on an augmented dataset tested on highly zoomed images validation set, outperforming less zoomed or less detailed validation sets. These findings underscore the efficacy of this innovative approach in capturing real-time plant images. Leveraging the PTZ camera's zoom, pan, and tilt capabilities enables comprehensive visualization of plant traits and adaptability to evolving growth patterns, thereby improving the results of plant feature detection. The amassed imagery serves a dual purpose by acting as training data for AI models, highlighting their potential to facilitate future research endeavors demanding extensive and scalable plant information. • Introducing a high-throughput plant phenotyping method for capturing real-time imagery of plants. • Proposing PTZ camera's imaging mechanisms for visualizing diverse and detailed plant features. • Improved results arise from applying plant feature detection to zoomed images taken with a PTZ camera. [ABSTRACT FROM AUTHOR]

[Display omitted] • Extracts rich in amino acids and phenols were achieved. • The T. obliquus culture (without treatment) achieved the highest germination index. • The supernatant and culture of HPH-1200 showed the highest auxin-like effect. • Only the initial T. obliquus culture showed cytokinin-like effect. • Both biomasses had similar NPK contents compared to commercial organic fertilizer. In the present work, two downstream processes − high-pressure homogenization at 100 (HPH-100) and 1200 bar (HPH-1200), and enzymatic hydrolysis (EH) − were tested to produce biostimulant extracts from Tetradesmus obliquus grown in piggery wastewater at two concentrations (12.8 and 88.3 g/L). Extracts before and after centrifugation (C) were evaluated in four bioassays using garden cress (germination), mung bean (auxin-like activity), and cucumber (auxin- and cytokinin-like activity) relative to distilled water. The initial microalgal culture, without any treatment, had the best germination results (162 % at 0.2 g/L) and the only one that showed cytokinin-like activity (141 % at 0.5 g/L). In both auxin-like bioassays, the HPH-1200 + C and EH + C originated high values (186 and 155 % for cucumber, 290 and 285 % for mung bean, respectively). For mung bean, the HPH-1200 achieved the highest auxin-like effect (378 %). Finally, the extracted biomass contained essential nutrients for biofertilization, complementing the biostimulant extracts for sustainable agriculture application. [ABSTRACT FROM AUTHOR]

• Cucumber as donor and melon as receiver crop were tested in a cascade soilless system. • Compared to monoculture the cascade system increased the water use efficiency by 22%. • Compared to monoculture the cascade system increased nutrients use efficiency by 20%. • Compared to monoculture the cascade system reduced about 80% nutrients leaching. Enhancing the sustainability of horticultural crops in the Mediterranean region is of great importance, with a particular focus on the simultaneous reduction of water and fertiliser consumption and the improvement in crop productivity. In the current study, the efficacy of a cascade soilless system was assessed, which utilised the drainage of a cucumber (donor) cultivation to meet the nutritional and water needs of a melon (receiver) crop, both grown in perlite slabs. Melon crop irrigated with standard nutrient solution, served as control treatment. The cascade system was assessed in terms of water (WUE), nitrogen (NUE), phosphorus (PUE), and potassium (KUE) use efficiency. In addition, the total consumption and the mineral composition of the supplied nutrient solution during cropping were monitored and the N and P emissions to the environment were estimated. The effects of the treatments on plant growth and yield as well as the nutrient absorption of the melon crop, was also examined. The results showed that the WUE of the cascade system demonstrated a 22% increase compared to the cucumber monoculture system. The NUE and PUE increased substantially by 21.7% and 21.8% compared to the monoculture system respectively, while the KUE increased by 9%. Notably, plant growth and yield of the receiver crop were not affected when fertigated with the drainage solution derived from a cucumber crop. Finally, the implementation of the cascade system contributed to a remarkable reduction in N and P leaching into the environment by 70% and 86%, respectively. These results underscore the potential of cascade soilless systems as a sustainable and resource-efficient approach in Mediterranean horticulture. [ABSTRACT FROM AUTHOR]

• Viviparous germplasm resources concentrate in South China and North China types. • High temperature, withered plant, and postripeness promote vivipary. • BR, CTK, IAA, and JA signal activates in vivipary while ABA and ETH signal inhibits. • Starch degradation and soluble sugar synthesis are vigorous in vivipary. • Amino acids, fatty acids, and phenylpropanoids biosynthesis up-regulate in vivipary. Vivipary is a common phenomenon in nature. However, vivipary in cucumber affects seed production and processing, and it is necessary to understand the mechanism. In this study, the phenotype, physiology and transcriptome of easy-viviparous cucumber inbred line 'D1158' were analyzed. The vivipary manifested on the 35th day after pollination, and the viviparous germination rate reached 50 % on the 55th day after pollination. The viviparous germplasm resources were mainly concentrated in South China and North China types rather than European greenhouse and pickle types. Besides, high temperature, withered plants, and postripeness promoted vivipary. Differentially expressed genes in transcriptome were enriched in hormone signal transduction, energy and nutrient metabolism, and cellular component biosynthesis pathways. BR, CTK, IAA, and JA signals were activated, while ABA and ETH signals were inhibited in vivipary. Starch degradation and biosynthesis of soluble sugars, amino acids, fatty acids, and phenylpropanoids were up-regulated, possibly facilitating cell proliferation in vivipary. A potential regulatory pattern in the formation of vivipary in cucumber was constructed, and candidate genes were predicted. The results may enhance the comprehension of vivipary in cucumber and provide a basis for future research. [ABSTRACT FROM AUTHOR]

Cucumber (Cucumis sativus L.) fruit is susceptible to chilling injury (CI) during low-temperature storage; however, the mechanism behind the chilling response of cucumber fruit is not fully understood. Cellular responses to low-temperature conditions should be determined to identify the factors behind CI occurrence and chilling tolerance in postharvest fruit. In this study, the CI incidence in cucumber fruit stored at 13 °C (non-chilling temperature) and 2 °C (chilling temperature) were compared to determine the key factors involved in the chilling response. Transcriptome analysis revealed that different metabolite and phytohormone signalling pathways were activated in the two storage temperatures. Thus, metabolites and phytohormones were profiled to gain a deeper understanding of their roles in the chilling response. Sucrose and amino acids such as isoleucine, serine, valine, and threonine significantly accumulated in the fruit stored at 13 °C compared with those stored at 2 °C. Among the analysed phytohormones, more abscisic acid accumulated at 13 °C than at 2 °C as an early response to non-chilling temperature. Meanwhile, salicylic acid levels and expressions of its signalling genes increased with persistent exposure to 2 °C as a response to chilling stress. Phytohormones such as brassinolide, ethylene, indole-3-acetic acid, jasmonic acid did not significantly accumulate at 2 °C. However, their signalling genes were upregulated in the fruit stored at 2 °C compared to 13 °C. These results suggest that the transcriptional activation of phytohormone signalling pathways, rather than their biosynthesis, plays a crucial role in the chilling response. These findings provide insights into chilling response and complex interplay of various molecular components during the low-temperature storage of cucumber fruit. • Severe chilling injury symptoms in cucumber were observed at 2 °C but not at 13 °C. • Transcriptomes and metabolic processes were differentially affected by temperatures. • Abscisic acid, sucrose, and amino acid levels increased as early response to 13 °C. • Salicylic acid levels increased as a late response to prolonged chilling stress. • Transcriptional activation of phytohormone signalling may play a key role at 2 °C. [ABSTRACT FROM AUTHOR]

Plant HRS1 (hypersensitive to low phosphate (Pi)-elicited primary root shortening 1) and its homologs have been primarily characterized in Pi and nitrogen responses. However, their regulatory roles in cold responses remain largely unexplored. Here, we characterized the functional roles of HRS1 homolog 2 (CsHHO2) in regulating cold resistance in harvested cucumber fruit and examined the dependency of the role on glycine-rich RNA-binding protein 3 (CsGR-RBP3) gene expression. Cold treatments strongly induced CsHHO2 expression in cucumber fruit. GUS staining and expression analysis revealed that cold treatment stimulated CsHHO2 expression, at least partially, by enhancing the promoter activity. Subcellular localization results indicated that the green fluorescent protein (GFP)-tagged CsHHO2 proteins were localized to both the nucleus and the cytoplasm (potentially the plasma membrane), with confirmed nuclear localization when co-overexpressed with mCherry. Reducing CsHHO2 expression in cucumber fruit through VIGS significantly compromised the chilling tolerance, while its overexpression in cucumber fruit and Arabidopsis plants enhanced cold tolerance. The results of electrophoretic mobility shift assay (EMSA), yeast one-hybrid (Y1H) assay and dual-luciferase reporter (DLR) assay indicated that CsHHO2 specifically bound to the promoter of CsGR-RBP3 , and enhanced its transcription. Transcriptomic analysis indicated that most differentially expressed genes (DEGs) modulated by CsHHO2 and CsGR-RBP3 proteins were identical, and the common DEGs were mainly enriched in several stress defense pathways, such as plant-pathogen interaction, phenylpropanoid biosynthesis, and plant hormone signal transduction. Functional complementation analysis of CsHHO2 and CsGR-RBP3 in cucumber fruit revealed that CsGR-RBP3 expression were indispensable for CsHHO2-modulated cold resistance. These results collectively suggest that CsHHO2, activated by cold signals, positively regulates the chilling tolerance of cucumber fruit by enhancing CsGR-RBP3 expression. Overall, this work suggests CsHHO2 as a key regulator of cold tolerance in cucumber fruit, provides key genetic resources for breeding cold-resistant cucumbers, and sheds novel insight into the roles of HRS1 family members in regulating plant development under environmental stresses. • Cold treatments induce CsHHO2 expression in harvested cucumber fruit. • CsHHO2 positively regulates the chilling tolerance of cucumber fruit. • CsHHO2 could enhance the transcription of CsGR-RBP3. • CsGR-RBP3 integrates multiple defense pathways to confer cold tolerance. [ABSTRACT FROM AUTHOR]

A Eu-MOF was synthesized hydrothermally with 5-(4′-carboxybenzyl)oxy) isophthalic acid and 4,4′-bipyridine as a guest molecule, and had a good fluorescence quenching effect with the low detection limit on 2,4,6-trinitrophenol (0.886 μM), ornidazole (0.732 μM), pyrimethanil(0.569 μM) and Cr 2 O 7 2−(2.8 μM) in aqueous solution, respectively. A Cr 2 O 7 2−@Eu-MOF fluorescence silencing system was constructed, and the fluorescence gradually recovered forming a unique fluorescence "on" −" off "-" on" sensor when ascorbic acid (AA) was added. The fluorescence sensing mechanisms of Eu-MOF were investigated in detail by experimental and theoretical calculation. In addition, we prepared Eu-MOF@PVA-based fluorescent test paper for the naked eye detection of Cr 2 O 7 2− in aqueous solution. Eu-MOF was applied to the detection of pyrimethanil residues in the skins of grape, cucumber, and tomato, apple and kiwi. [Display omitted] • A new Eu-MOF based on 5-(4′-carboxybenzyloxy) isophthalic acid with 4,4′-bipyridine guest; • It had a good fluorescence quenching effect on 2,4,6-trinitrophenol, pyrimethanil, and Cr 2 O 7 2−in aqueous solution respectively; • A unique fluorescence "on–off-on" sensor was formed by Cr 2 O 7 2−@Eu-MOF and ascorbic acid; • Eu-MOF@PVA-based fluorescent test paper for the naked eye detection of Cr 2 O 7 2− in aqueous solutions; • Eu-MOF was applied for the detection of pyrimethanil residues in the skins of grape, cucumber, and tomato, apple and kiwi. Europium metal–organic frameworks (Eu-MOFs) have unique application prospects in the field of fluorescence sensing, due to the fluorescence characteristics of Eu3+ ion and organic ligands, and the advantages of obvious red luminescence, long emission lifetime, large Stokes shift, and high quantum yield. In this study, a novel Eu-MOF was synthesized hydrothermally using europium acetate hexahydrate (Eu(Ac) 3 ·6H 2 O), 5-(4′-carboxybenzyloxy) isophthalic acid (5-H 3 CIA), and 4,4′-bipyridine (4,4′-bipy). Structural analysis revealed that the Eu-MOF exhibited a three-dimensional framework with 4,4′-bipyridine as the guest molecule. Fluorescence sensing experiments revealed that 2,4,6-trinitrophenol, ornidazole, pyrimethanil, and Cr 2 O 7 2− effectively quenched the fluorescence of the Eu-MOF in aqueous solution, with corresponding limits of detection as low as 0.886, 0.732, 0.569, and 2.800 μM, respectively. Exploiting the ability of Cr 2 O 7 2− to quench the fluorescence of the Eu-MOF, we devised a Cr 2 O 7 2−@Eu-MOF fluorescence silencing system that, in the presence of ascorbic acid, gradually recovered its fluorescence to form a unique fluorescence "on–off-on" sensor. In addition, the fluorescence sensing mechanism of Eu-MOF was studied, the fluorescence test was prepared to detect Cr 2 O 7 2− with an open eye, and the content of pyrimethanil was detected in real samples, including cucumber skin, tomato skin, grape skin, apple and kiwi. [ABSTRACT FROM AUTHOR]

In plants, alcohol dehydrogenases (ADHs) are involved in stress response, organ development, fruit ripening, and metabolite synthesis. However, little is known regarding ADH-encoding genes (ADHs) in Cucurbita moschata which is usually used as a rootstock for cucumber, melon, watermelon, and other cucurbit crops to resist soil-borne diseases and abiotic stresses. We identified 11 CmoADHs in the C. moschata genome that were unevenly distributed across seven chromosomes. These genes were predicted to encode stable cytoplasmic acidic proteins, sharing a low degree of identity with each other. The genes exhibited different intron–exon structures. Analysis of cis -acting regulatory elements showed that CmoADHs contain environmental stress-, hormone response-, light response-, and development/tissue specificity-related elements in their promoters. Expression pattern analysis revealed that CmoADH2 , CmoADH3 , CmoADH4 , CmoADH9 , CmoADH10 , and CmoADH11 had the highest expression levels in the roots, which were significantly higher than those in the other tested tissues. These six genes may play important roles in the growth and development of roots, and in related abiotic stress responses. CmoADH1 , CmoADH5 , CmoADH6 , CmoADH7 , CmoADH8 had the highest expression in the apical region and could be involved in the differentiation of newly formed tissues. To study the role of CmoADHs in abiotic stress, salt, drought, low temperature, and ethephon treatments were performed. Under drought conditions, CmoADHs showed different expression trends. The expression levels of CmoADH1 , CmoADH2 , CmoADH3 , and CmoADH9 increased significantly and peaked after 1 h of drought treatment, indicating that these four genes are more sensitive to drought stress. Under salt treatment, all CmoADHs showed a significant increase or decrease in expression within 6 h, except for CmoADH5 and CmoADH10 , which were insensitive to salt treatment. The expression of most of the CmoADHs was significantly downregulated by low-temperature treatment. Ethephon treatment significantly induced the expression of all the CmoADHs , except CmoADH2 , to different degrees within 12 h. CmoADH9 was found to be involved in root growth and drought stress resistance. Identification of these ADH genes can provide useful resources for conferring stress resistance in other economically important crops. • Eleven alcohol dehydrogenase genes (ADHs) were identified in Cucubita moschata. • ADHs were characterized using bioinformatics and expression analysis was performed. • Several cis -acting regulatory elements are present in the promoter of each CmoADH. • Transgenic Arabidopsis plants overexpressing CmoADH9 performed better under drought stress. [ABSTRACT FROM AUTHOR]

Aphid (Aphis gossypii Glover) attack frequently results in a significant loss of output and deterioration of fruit quality in cucumber (Cucumis sativus L.). Phloem protein 2 (PP2) is conserved as a phloem lectin in plants, and few studies have been conducted on the regulatory mechanism of PP2. Based on our previous study of CsPP2-A1 in cucumber, to further investigate the biological function of CsPP2-A1, we compared the changes of selectivity, non-selectivity, colonization, reproductions of aphids, and the phenotype in wild type (WT), CsPP2-A1 overexpressing (CsPP2-A1- OE), and CsPP2-A1 interfering (CsPP2-A1- RNAi) cucumber plants after inoculation with aphids. We found that CsPP2-A1 -OE cucumber plants generated resistance to aphids. The aphid colonization rate and number of reproductions of CsPP2-A1 -OE cucumber plants were significantly lower than that of WT and CsPP2-A1 -RNAi cucumber plants. Through Pearson's correlation and principal component analysis (PCA), it was found that CsPP2-A1 played a crucial role in the balance of reactive oxygen species (ROS) in plants. Overexpression of the CsPP2-A1 resulted in increased levels of antioxidant enzyme, eliminating ROS and preventing the damage by ROS in cucumber. Furthermore, nutritional imbalance for aphids and content of secondary metabolites were increased in overexpressed CsPP2-A1 cucumber plants, and thus preventing aphid attack. These together may improve cucumber resistance against aphids and the mechanism of CsPP2-A1 defense against aphids was preliminarily explored. [ABSTRACT FROM AUTHOR]

• Effects of SMF on four kinds of foods were compared from micro and macro scales. • SMF tended to decrease the ice crystals size for four kinds of fruits and vegetables. • Higher SMF intensity did not always produce smaller ice crystals. • Significant effect of SMF on macro-scale quality only appeared in one kind of food. Novel food freezing technology assisted by static magnetic field (SMF) has emerged in recent years. However, few papers have compared the effects of SMF on different kinds of foods under the same experimental conditions. This study investigated the effects of 0 to 45 mT SMF intensities on apple, peach, cucumber and Indian jujube from micro and macro scales. The parameters including ice crystal size, time through -1 ∼ -5 °C, drip loss and texture were compared. The results show that SMF tended to decrease the ice crystals size for four kinds of fruits and vegetables, and the optimal SMF intensity varied with the types of foods. The beneficial effect of SMF on reducing ice crystal size did not always appear in macro-scale freezing. Positive effects of SMF on macro-scale parameters only appeared in Indian jujube, and stronger intensity brought better quality. [ABSTRACT FROM AUTHOR]

• Non-conventional chlorination of an alkene double bond with thionyl chloride. • Docking studies of the most active imide. • Potential energy surface analysis along the reaction coordinate. • DFT calculations to aid in the structural identification of the favored product. Cyclic imides are versatile molecules in organic synthesis and have a wide range of properties and applications. Herbicidal activity is one of the properties studied and has been the subject of several studies. In this study, we describe the synthesis of a dichlorinated cyclic imide, carried out in three steps, starting from maleic anhydride and (S)-(-)- α -methylbenzylamine. The last step involved a Diels-Alder reaction to form the cyclic imide 4 ((3a R ,4 S ,7 R ,7a S)-3a,7a-dichloro-2-((S)-1-phenylethyl)-3a,4,7,7a-tetrahydro-1 H -4,7-methanoisoindole-1,3(2 H)‑dione). Structural identification was carried out using spectroscopic methods and theoretical calculations based on DFT, as well as DP4+ and CMAE probabilistic analyses. The biological tests revealed that the synthesized compounds exhibit significant phytotoxic activity, with the highlight being compound 3 , a haracterizat imide that showed inhibitory potential on the growth of Cucumis sativus, Lactuca sativa, Sorghum bicolor and Brachiaria decumbens , comparable to the commercial herbicide Dual, suggesting new opportunities for the development of bioactive molecules with application in agrochemistry. [Display omitted] [ABSTRACT FROM AUTHOR]

The combination of micro-nano bubble water (MNBW) with subsurface drip irrigation (SDI) is an effective and water-saving aerated irrigation technique. Biochar is a biomass resource with high porosity, alkalinity, and specific surface area. The effects of SDI with MNBW and biochar on crop photosynthetic characteristics, dry matter accumulation, and red soil (clay) aeration are not well understood. Three levels concentrations of dissolved oxygen (DO) in MNBW: O1 (4–5 mg/L), O2 (9–10 mg/L), and O3 (14–15 mg/L), as well as three levels amount of biochar application (BA): B1 (20 t/hm2), B2 (40 t/hm2), and B3 (60 t/hm2), and one control group (CK, O: 4–5 mg/L, B: 0 t/hm2) were the subjects of this study, followed by a two-factor randomized block design. The study examined the aeration practices of the red soil (clay) and the responses of greenhouse-grown cucumbers to SDI over the first and second growing seasons. The concentration of DO in MNBW and the amount of BA had a substantial impact on yield, dry matter accumulation, key quality indicators, photosynthetic characteristics, and soil aeration (P < 0.05). Compared to CK, in the two-season experiment, the average soil aeration porosity (SAP) increased by 0.53–44.00 %, the soil oxygen content (SO) increased by 0.47–31.80 %, the net photosynthetic rate (Pn) increased by 1.91–50.78 %, the dry matter accumulation increased by 10.53–69.19 %, the yield increased by 1.72–44.23 %, and the water use efficiency (WUE) improved by 0.42–76.57 %. Plant dry weight, cucumber yield, irrigation water use efficiency, vitamin C, and the sugar-acid ratio all have a substantial positive correlation (P < 0.05) with the photosynthetic rate. Soil aeration porosity, soil oxygen, photosynthetic rate, plant dry weight, and irrigation water use efficiency all have a substantial positive correlation with yield (P < 0.05). Micro-nano bubble water enhanced the oxygen content and soil aeration porosity, while biochar increased the porosity and lowered the bulk density of the soil. The "oxidation-porous" qualities of micro-nano bubble water and biochar combined to enhance clay soil aeration, promote cucumber development, accelerate photosynthetic rate and dry matter buildup, and enhance yield and quality.O3B3 (O3 14–15 mg/L, B3 60 t/hm2) was the optimal treatment when factors like yield and quality were taken into consideration. The research findings provide theoretical basis and feasible approaches for improving the aeration of clay and enhancing the quality and efficiency of greenhouse crops. • Micro-nano bubble water (MNBW, oxidation) increased soil oxygen and soil redox potential. • Biochar (porous) decreased soil bulk density and significantly increased soil porosity and soil aeration porosity. • Aeration of clayey red soil was enhanced by "oxidation-porous" properties of MNBW and biochar. • MNBW in combination with biochar promoted dry matter accumulation and net photosynthetic rate. • Fruit cucumber yield, and quality, IWUE were improved by MNBW combined with biochar. [ABSTRACT FROM AUTHOR]

• The fruit skin glossiness determine on the appearance quality of cucumber. • Candidates genes and genetic mechanism regulation into wax and bloom forming are summarized. • The future research direction of wax and bloom and its significance for future breeding were prospected. Cucumber (Cucumis sativus L.) is an important horticultural crop in China. Consumer requirements for aesthetically pleasing appearances of horticultural crops are gradually increasing, and cucumbers having a good visual appearance, as well as flavor, are important for breeding and industry development. The gloss of cucumber fruit epidermis is an important component of its appeal, and the wax layer on the fruit surface plays important roles in plant growth and forms a powerful barrier against external biotic and abiotic stresses. The wax of the cucumber epidermis is mainly composed of alkanes, and the luster of cucumber fruit is mainly determined by the alkane and silicon contents of the epidermis. Several genes, transcription factors, and transporters affect the synthesis of ultra-long-chain fatty acids and change the silicon content, further altering the gloss of the epidermis. However, the specific regulatory mechanisms are not clear. Here, progress in research on the luster of cucumber fruit epidermis from physiological, biochemical, and molecular regulatory perspectives are reviewed. Additionally, future research avenues in the field are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Delayed harvesting led to significant increases in length, diameter, and weight of cucumber fruit. • 1,907 non-volatile metabolites and 624 volatile metabolites were detected in cucumber fruits harvested at 12, 24, and 36 days after pollination. • Grafting did not significantly affect length, diameter, and weight of cucumber fruit compared to self-rooted plants. • 113 non-volatile and 11 volatile differential metabolites were identified between self-rooted and grafted cucumber fruits. Cucumber is a widely consumed vegetable crop known for its rich nutrient composition and distinctive flavor, influenced by both volatile and non-volatile compounds. Grafting and delayed harvesting are crucial strategies for increasing cucumber yield. The present study investigates the impact of delayed harvesting at different developmental stages and grafting on the metabolic profile, flavor, and overall quality of cucumber fruits Yuxiu 2 (YX) using UPLC-MS/MS and GC-MS/MS techniques. The results indicate that delayed harvesting of YX led to significant increases in length, diameter, and weight from 12 to 24 days after pollination (DAP), with minimal growth beyond 24 DAP. However, grafting did not affect these physical parameters compared to self-rooted plants. Furthermore, metabolic profiling reveals that delayed harvesting enhances the concentration of certain non-volatile metabolites, including alkaloids, organic acids, and phenolic acids, while leading to a reduction in flavonoid contents. Overall, 140 non-volatile and 26 volatile differential metabolites were screened at three developmental stages. Notably, four new organic acids (6-amino hexanoic acid, 5-amino valeric acid, 1-hydroxy-2-naphthoic acid, and succinic semialdehyde) and three novel alkaloids (3-indole acetonitrile, epinephrine, and serotonin) were identified. Volatile compounds, such as aldehydes, esters, terpenes, alcohols, and ketones, exhibit a peak in concentration at 24 DAP, followed by a decline. The characteristic cucumber flavor compound, (E,Z)-2,6-nonadienal, remains consistent across all developmental stages. In grafted cucumber fruits, a total of 113 non-volatile and 11 volatile differential metabolites were screened, and among them, ten unique non-volatile metabolites were detected in grafted fruits, contributing to the sour and bitter taste of cucumbers. Moreover, some of the metabolites like (1S,4S,4aR)-1-isopropyl-4-methyl-7-methylene-1,2,3,4,4a,5,6,7-octahydronaphthalene with pentylenetetrazol contribute to an undesirable camphor-like odor. The study concludes that while delayed harvesting and grafting practices can increase cucumber yield, they also significantly alter the fruit's metabolic profile, impacting taste and flavor. [ABSTRACT FROM AUTHOR]

• 'Scopatizzo': a landrace of unripe melon (C. melo L.) to be consumed as alternative to cucumber (C. sativus L.); • closed cycle soilless system to increase the use efficiency of nutrient solution; • Water culture systems to avoid any stress phenomena due to the use of moderately brackish water; • Enhancement of an Apulian landrace of unripe melon to counteract the loss of agro-biodiversity. The aim of agricultural activity is to produce more, consuming less, focusing on a more efficient use of production inputs and on a reduction of biodiversity loss. Irrigation water salinization is one of the most severe causes of yield reduction in modern agriculture. Basing on this, the aim of the experimental trial was to study if nutrient film technique (NFT) system, with a complete nutrient solution (NS) recirculation, may be an effective system to counteract the negative effects of raising NaCl concentrations in the NS on crops. A landrace of unripe melon (Cucumis melo L.) called 'Scopatizzo' was grown in a spring-summer cycle, in the greenhouse, in an NFT system with a closed management of NS and three levels of NaCl (0, 2.5 and 5 mM). 'Scopatizzo' plants absorbed an average of 145 L of NS per plant, with daily uptake increasing from 0.5-0.8 L·plant-1 to over 2 L·plant-1, linearly related to total light integral (TLI). Higher NaCl levels raised NS electrical conductivity, with significant differences over time. Water use efficiency (WUE) and average production were 27.6 L·kg-1 and 5.31 kg·plant-1 respectively and fruits with NaCl had higher titratable acidity but lower glucose. NaCl enhanced gas exchange, increasing photosynthetic rate, stomatal conductance, and transpiration, while altering electron transport properties. NFT as a cultivation system has proven to allow the use of moderately saline water without compromising the yield and fruit quality of 'Scopatizzo' which represents a valid alternative to the cultivation of cucumber. Further study will be necessary in order to verify up to which concentration of NaCl no significant stress symptoms are identified on the production and growth of the plant. [ABSTRACT FROM AUTHOR]

• Comparing coupled and decoupled aquaponics with hydroponics under the same climate. • DCAP systems consistently produced higher yields compared to CAP and HP. • Compared to DCAP and HP, CAP presents higher crop water use efficiency. • DCAP achieves significant fertiliser savings. • DCAP presents a promising "plant-centric" approach for sustainable agriculture. Aquaponics, a sustainable agricultural method, is gaining attention for its closed-loop system's potential to address diverse environmental and economic challenges in traditional agriculture. The aim of this study was to fill knowledge gaps in scaling up lab-scale systems to larger-scale decoupled aquaponics, offering a comprehensive understanding of the system's productivity and water and fertiliser use efficiency. In coupled aquaponics (CAP), the aquaculture, and the hydroponic units are arranged in a single loop, and water flows continuously from the fish tanks to the plant unit and vice-versa. In decoupled aquaponics (DCAP), the aquaculture and hydroponics units are arranged in a multi-loop setup as separate functional units that can be controlled independently. This work compared coupled aquaponics, decoupled aquaponics and hydroponics (HP, in perlite slabs) under the same climatic conditions with a substrate grown crop in a pilot scale greenhouse. The evaluation of growth parameters, yield, water, and fertiliser use for basil, cucumber, parsley, and tomato cultivations co-cultivated with the tilapia recirculating aquaculture system (RAS) are presented. The highest yields were achieved by DCAP plants in all experiments (15% higher than HP and 19% than CAP for basil, 38% than CAP in cucumber, 17% and 72% than HP and CAP in parsley, and 8% and 55% for HP and CAP in tomato experiments). The CAP treatment that did not receive any fertilisers presented the highest water use efficiency compared to both HP and DCAP treatments. Also, compared to HP, the DCAP treatment presented higher water and fertilisers use efficiency. Consequently, the adoption of decoupled aquaponic systems is the key to aquaponic evolution in the future. [ABSTRACT FROM AUTHOR]

• The changes in the sugar, fatty acid, and aroma in cucumber fruits under shading treatment. • Transcriptomic revealed differences in flavor of cucumber under shading and unshading treatment. • The role of photosynthesis in regulating the formation of aldehydes and alcohols aroma of cucumber. The distinctive aroma of cucumber fruit is highly appreciated by consumers. The aroma of cucumber fruit is primarily influenced by the concentration of six- and nine-carbon aldehydes and their related alcohols, which are produced by metabolites of the lipoxygenase pathway. The formation of volatile aroma compounds in cucumber fruits is inseparable from plant photosynthesis, but the mechanism of light regulation of volatile compound synthesis is unclear. In this study, the effects of shading on aroma, undesirable flavours, sugars and fatty acids metabolisms in cucumber fruit were investigated. The results showed that (E)-2-Nonenal, (E, Z)-2,6-Nonadienal, and other aldehydes were significantly increased, while 1-Nonanol, 1-Hexanol, and other alcohols were significantly decreased, undesirable flavours dominated by (E)-2-Nonenal were strongly promoted to accumulate 1.56-fold in commercially ripe fruit under shading. Furthermore, the contents of sugars and fatty acids were decreased by 28 % and 12 % respectively. Transcriptomic analysis showed 35 differentially expressed genes in the biosynthesis and metabolism of fatty acids and lipoxygenase pathway in photosynthesis under shading were significantly down-regulated. Based on the comprehensive analysis of multi-omic data, it was shown light regulates the formation of volatile aroma substances in fruits by regulating the substrate level of the fatty acid metabolic pathway and the expression of related genes. [ABSTRACT FROM AUTHOR]

• Low light stress induced hypocotyl elongation in cucumber. • The candidate region of hypocotyl elongation under low light was mapped on Chr 2 by BSA-seq. • Low light regulate the expression of auxin related genes. Cucumber (Cucumis sativus L.) is cultivated worldwide and is known to be photophilic and thermophilic. Low light stress (LLS) in winter and spring in Northern and early spring in Southern China has a severe impact on the growth and development of greenhouse cucumbers. However, the molecular regulatory mechanisms of LLS in cucumbers remain unclear, which seriously limits the development of cucumber breeding under LLS. In this study, we investigated hypocotyl differences in two cucumber lines grown under LLS and normal (CK) condition. Under LLS, the activities of ascorbate peroxidase (APX), superoxide dismutase (SOD), peroxidase (POD), and malondialdehyde (MDA) declined tovarying degrees compared with CK, and Y8 showed a relatively small decline. The hypocotyl length of the F 2 population is a quantitative trait controlled by multiple genes under LLS conditions. The candidate region for hypocotyl elongation under LLS was mapped to chromosome 2 using bulk segregant analysis sequencing (BSA-seq). In addition, transcriptome analysis revealed 2786 differentially expressed genes (DEGs), of which 871 DEGs were specifically identified between Y5 and Y8 under LLS. Among these DEGs, 12 DEGs were involved in plant hormone signal transduction. Association analysis of the BSA-Seq and RNA-Seq results suggested that 36 DEGs were as candidate genes. Furthermore, three TFs (NAC, MYB and C2H2) may be considered the most likely candidate genes of hypocotyl elongation under LLS. Our results provide comprehensive understandings of the mechanism of hypocotyl elongation under LLS, and contribute to foundation for cloning the genes involved in hypocotyl elongation under LLS. [ABSTRACT FROM AUTHOR]

Highly crystalline Zn 1-x Ni x O [x = 0, 0.5 & 1.0 wt%] nanoparticles were successfully synthesized by chemical and green synthesis routes at different doping concentrations. XRD, FE-SEM, EDS, UV, FTIR and VSM characterized the obtained nanoparticles from both routes for micro-structural, morphological, compositional, optical and magnetic properties respectively. X-ray diffraction confirms the formation of hexagonal wurtzite structure with an average crystallite size lies in the range 14–35 nm. FESEM analysis reported well-distinguished small bricks like grains were observed for green synthesized samples, whereas, chemically synthesized samples possess spherical grains.The EDS study confirms the presence of Ni, O and Zn elements closely to the stoichiometric amount. The optical Eg was found to be reduced with Ni doping and minimum bandgap of 2.4 eV for green synthesized and 2.2 eV for chemically synthesized samples has been observed. The photocatalytic performance of methylene blue dye was studied and resulted in the highest degradation efficiency of 88.8 % is achieved at 150 min of sunlight exposure. The obtained magnetic results revealed that the presence of Ni doping introduced ferromagnetism behaviour in ZnO nanoparticles and makes them suitable material for spintronic device application. [ABSTRACT FROM AUTHOR]

Cold stress detrimentally influences fruit development, leading to a substantial yield reduction in many fruit-bearing vegetables. Cucumber, a vegetable of subtropical origin, is especially sensitive to cold. Cold-inducible parthenocarpy (CIP) promises fruit yield under cold conditions. Previously, we identified a CIP line EC5 in cucumber, which showed strong parthenocarpy and sustained fruit growth under cold conditions (16°C day/10°C night). However, the candidate gene and genetic mechanism underlying CIP in cucumber remain unknown. In this study, both BSA-seq and conventional QTL mapping strategies were employed on F 2 populations to delve into the genetic control of CIP. A single QTL, CIP5.1 , was consistently mapped across two winter seasons in 2021 and 2022. Fine mapping delimited the CIP locus into a 38.3 kb region on chromosome 5, harboring 8 candidate genes. Among these candidates, CsAGL11 (CsaV3_5G040370) was identified, exhibiting multiple deletions/insertions in the promoter and 5′UTR region. The CsAGL11 gene encodes a MADS-box transcription factor protein, which is homologous to the genes previously recognized as negative regulators in ovule and fruit development of Arabidopsis and tomato. Correspondingly, cold treatment resulted in decreased expression of CsAGL11 during the early developmental stage of the fruit in EC5. A promoter activity assay confirmed promoter polymorphisms leading to weak transcriptional activation of CsAGL11 under cold conditions. This study deepens our understanding of the genetic characteristics of CIP and elucidates the potential role of the CsAGL11 gene in developing cucumber cultivars with enhanced fruiting under cold conditions. • CIP promises stable fruiting under cold conditions. • The CIP5.1 locus was fine mapped to a region of 38.3 kb on chromosome 5. • A putative candidate gene CsAGL11 was cloned. [ABSTRACT FROM AUTHOR]

Radical-induced polymerization in persulfate (PS)-based advanced oxidation process (AOP) is attracting attention in water decontamination. Herein, we revealed its new role in rapid recycling of perishable food wastes using KOH activated PS. A glucose (Glu) solution of 250 g C/L was applied to mimic the carbohydrate-rich raw material with 50–60% moisture in conventional composting, wherein boosted humification occurred after addition of solid KOH/PS. Intense heat release (from 25 to 79.4 °C), mainly generated from KOH dissolving and exothermic radical chain polymerization, was observed within 2 min. Solid KOH addition contributed to synergistic PS activation by base and self-heating, realizing complete PS decomposition and fulvic like acid (FLA, 210.8 g C/L) formation within 10 min. Extracted FLA promoted cucumber seed germination and fresh weight of chickweeds by 40.0% and 128.3%, respectively. Identified •OH and SO 4 •- played primary roles in FLA formation through aromatization, carboxylation, and polymerization, wherein several key reactive intermediates such as 5-hydroxymethylfurfural and aromatic radicals (i.e. 1,2,4-benzenetriol radical) were formed. Moreover, the humification process simultaneously produced K 2 SO 4 (i.e. the end product of PS decomposition) which could be used as a typical K/S fertilizer. Scaling-up humification of waste cooked rice and fertilization results further supported the potential of solid KOH/PS in efficiently converting food wastes into FLA and K+-rich compound fertilizer. • Persulfate/KOH realized glucose's fast humification by radical-induced polymerization. • Temperature rose from 25 to 79 °C in 2 min due to KOH dissolving and polymerization. • Base and self-heating synergistically activated persulfate (PS). • Product containing fulvic-like acid and K+ could be used as a compound fertilizer. • Waste cooked rice as a model food waste verified KOH/PS-induced humification. [ABSTRACT FROM AUTHOR]

Consumer preference in produce, defined by shape and size, heavily influences this market. Understanding the environmental and management factors that impact these features can improve a farmer's economic margins. Since sweetpotatoes are hand-harvested and tend to have varying shapes and sizes, this can result in unpredictable profit margins. Methods for predicting the aesthetic characteristics of sweetpotatoes using environmental and agronomic factors with machine learning have not been developed. Moreover, predicting crop shape and size using agricultural data analysis is challenging due to the need for integrating diverse and complex datasets, including genotypes, weather, field management, and spatial information, into predictive models. This study employed an iterative process involving data preparation, feature engineering, variable selection, and model selection to develop machine learning models that predict sweetpotato aesthetic traits from agronomic inputs. We collected and organized data from various sources with different formats, spatial, and temporal resolutions. After comparing the performance of different machine learning methods using cross validation, Bagging regression had the least predictive error in terms of RMSE and MAE for sweetpotato's length-to-width ratio (RMSE = 0.185, MAE = 0.147) and curvature (RMSE = 0.013, MAE = 0.010) predictions. Bagging regression outperformed a naive baseline by 29%–38% when predicting sweetpotato features Our study also determined that the Covington cultivar and GPS locations were the most important factors that influenced the shape and size of sweetpotatoes. Fertilizer prior to planting, rose as an important feature when predicting sweetpotato curvature. Precipitation had a greater impact on the prediction of length-to-width ratio when compared to predicting curvature. The methodology presented herein could be applied to other crops like cucumbers, eggplants, peppers, and potatoes, where the size and shape are important factors for determining their value. [Display omitted] • Collected, integrated, & processed data with varying temporal and spatial resolutions. • ML to infer impact of weather, genotype & agronomy on sweetpotato shape/size/grade. • Global positioning systems (GPS) were effectively used to assess spatial variability. • Covington cultivar and GPS were the most important predicting features. • Bagging regression had the least predictive error (RMSE & MAE). [ABSTRACT FROM AUTHOR]

[Display omitted] • Dynamic probing for micro-environment changes is an approach to get optimum model. • Micro-environment and AI-model are an approach to predict quality of produce. • Slight differences in cucumber and strawberry quality predicted by CNN and BP-ANN. • BP-ANN proposed as a non-destructive and accurate scheme to predict food quality. An AI model was proposed to combine micro-environment to predict fruit and vegetables quality. The quality indicators (firmness, weight loss and decay incidence) of cucumber and strawberry changes were detected and evaluated during transportation and supply chain. Temperature, RH and respiration were the essential indicators in cucumber and strawberry during supply chain, which was used to predict the quality of cucumber and strawberry by AI model. The training (80 %) and validation (20 %) of the three models were performed using a dataset composed of 170 cucumbers or 110 strawberries. Compared with CNN model (>91 % in terms of R c 2, >82 % in terms of R p 2), the BP-ANN model yielded higher prediction precision for both the firmness and weight loss of cucumbers (>95 % in terms of R c 2, >94 % in terms of R p 2 and >4 in terms of RPD) and decay incidence and weight loss of strawberry data sets (>97 % in terms of R c 2, >98 % in terms of R p 2 and >6 in terms of RPD). CNN model for cucumber exhibited high predictive performance (RPD > 3), whereas RPD of CNN model for strawberry was below 3, indicating CNN model was not suitable to predict the decay incidence and weight loss of strawberry. PLSR was not suitable for modeling methods with nonlinear regression. This would provide a non-destructive and reliable quality evaluation and supply chain management. [ABSTRACT FROM AUTHOR]

Chlorpyrifos, a prime insecticide encountered in numerous agricultural products, is associated with an array of adverse health implications, notably endocrine disturbances and carcinogenic tendencies. Monitoring the environment and controlling quality requires a rapid and simple method for determining the organophosphate insecticide. Overcome the universal challenge postured by this contaminant, this study presents a novel strategy to fabricate an electrochemical sensor based on Iron MOFs, synthesized using 3,5-pyrazoledicarboxylic acid (PyDA) using one-pot solvothermal method with carbon nanofiber matrix for sensing the chlorpyrifos. Notably, this MOF anchored electrode owns important fundamental features such as an expansive surface area, abundant active sites, a vast operational spectrum linear range (1.0–150 μM), a minimal detection threshold (15.1 nM), and an amplified sensitivity towards chlorpyrifos. This Fe-PyDA/CNF/GCE electrode not only showcased more extraordinary electrochemical attributes, but its broad linear detection range and low detection threshold emphasize its ability for real-world applications with reasonable recoveries. [Display omitted] • Flexible porous Fe-PyDA/CNF anchored mat was prepared via one-pot in-situ solvothermal process. • Evaluation of electrochemical properties of hybrid mat modified GCE towards chlorpyrifos in neutral electrolyte. • Phosphate buffer solution (pH = 7.0) have used for electrochemical sensing. • The Fe-PyDA/CNF/GCE electrode demonstrated a broad linear range from 1 to 150 μM along with an ultralow LOD and LOQ of 15.1 and 50.3 nM, respectively. • Practical applicability has been tested in real tomato juice and cucumber samples. [ABSTRACT FROM AUTHOR]

Low temperature (LT) is an important environmental factor affecting the growth and yield of plants. Melatonin (MT) can effectively enhance the LT tolerance of cucumber. This study found that LT stress induced the expression of Comt1 (caffeic acid O-methyltransferase 1), with the highest expression being about 2-times that of the control. Meanwhile, the content of MT was found to be roughly 63.16% of that in the control samples. Compared with LT treatment alone, exogenous MT pretreatment upregulated the expression levels of TOR (Target of rapamycin), PIN1 (Pin-formed 1), and YUC4 (YUCCA 4) , with maximum upregulations reaching approximately 66.67%, 79.32%, and 42.86%, respectively. These results suggest that MT may modulate the tolerance of cucumber seedlings to LT stress by regulating the expression of TOR , PIN1 , and YUC4. In addition, co-treatment with AZD-8055 (a TOR inhibitor) or NPA (N-1-naphthylphthalamic acid, an auxin polar transport inhibitor) and MT attenuated MT-induced resistance to LT stress, leading to higher levels of reactive oxygen species (ROS), reduced antioxidant defense capacity, and increased damage to the membrane system in cucumber seedlings. Concurrently, the content of osmoregulatory substances and the photosynthesis decreased. These results demonstrate that both TOR and auxin were required for MT to alleviate LT-induced damage in cucumber. In summary, the present study demonstrates that TOR and auxin signaling synergistically contribute to alleviating LT damage in cucumber seedlings by exogenous MT. These findings help us understand the function of MT and provide insights into the regulatory network of MT that regulates the LT tolerance of plants. • Melatonin (MT) responds positively to low temperature (LT) stress and enhances LT tolerance in cucumber seedlings. • Under LT stress, MT induces the expression of target of rapamycin (TOR) and auxin signaling related genes. • MT pretreatment enhances LT stress tolerance through interaction with TOR and auxin signaling. [ABSTRACT FROM AUTHOR]

[Display omitted] • CsPGIP2 was induced by Botrytis Cinerea. • A possible interaction between BcPG3 and CsPGIP2 was supported by protein interaction prediction and BiFC analysis. • The transgenic Arabidopsis exhibited higher antioxidant enzyme activities, lignin content, Pn , and photochemical activity. • CsPGIP2 can enhance resistance against gray mold disease. Polygalacturonase inhibitor protein (PGIP) restricts fungal growth and colonization and functions in plant immunity. Gray mold in cucumber is a common fungal disease caused by Botrytis cinerea , and is widespread and difficult to control in cucumber (Cucumis sativus L.) production. In this study, Cucumis sativus polygalacturonase-inhibiting protein 2 (CsPGIP2) was found to be upregulated in response to gray mold in cucumber. CsPGIP2 was detected in the endoplasmic reticulum, cell membrane, and cell wall after transient transformation of protoplasts and tobacco. A possible interaction between Botrytis cinerea polygalacturonase 3 (BcPG3) and CsPGIP2 was supported by protein interaction prediction and BiFC analysis. Transgenic Arabidopsis plants expressing CsPGIP2 were constructed and exhibited smaller areas of gray mold infection compared to wild type (WT) plants after simultaneous inoculation. Evans blue dye (EBD) confirmed greater damage for WT plants, with more intense dyeing than for the transgenic Arabidopsis. Interestingly, compared to WT, transgenic Arabidopsis exhibited higher superoxide dismutase (AtSOD1) expression, antioxidant enzyme activities, lignin content, net photosynthetic rate (Pn), and photochemical activity. Our results suggest that CsPGIP2 stimulates a variety of plant defense mechanisms to enhance transgenic Arabidopsis resistance against gray mold disease. [ABSTRACT FROM AUTHOR]

The fruit shape of cucumber is an important agronomic trait, and mining regulatory genes, especially dominant ones, is vital for cucumber breeding. In this study, we identified a short and fat fruit mutant, named sff , from an EMS mutagenized population. Compared to the CCMC (WT), sff (MT) exhibited reduced fruit length and increased dimeter. Segregation analysis revealed that the sff phenotype is controlled by a semi-dominant single gene with dosage effects. Through map-based cloning, the SFF locus was narrowed down to a 52.6 kb interval with two SNPs (G651A and C1072T) in the second and third exons of CsaV3_1G039870 , which encodes an IQD family protein, CsSUN. The G651A within the IQ domain of CsSUN was identified as the unique SNP among 114 cucumber accessions, and it was the primary cause of the functional alteration in CsSUN. By generating CsSUN knockout lines in cucumber, we confirmed that CsSUN was responsible for sff mutant phenotype. The CsSUN is localized to the plasma membrane. CsSUN exhibited the highest expression in the fruit with lower expression in sff compared to WT. Histological observations suggest that the sff mutant phenotype is due to increased transverse cell division and inhibited longitudinal cell division. Transcriptome analysis revealed that CsSUN significantly affected the expression of genes related to cell division, expansion, and auxin signal transduction. This study unveils CsSUN's crucial role in shaping cucumber fruit and offers novel insights for cucumber breeding. • Identification of a mutant with short and fat fruit (sff) in cucumber. • Cucumber transformation revealed that CsSUN is the causal gene for short and fat fruit. • Two SNPs are present inside CsSUN , which encodes an IQD family protein. • The SNP (G651A) inside the IQ domain of CsSUN is the primary cause of the functional alteration in CsSUN. [ABSTRACT FROM AUTHOR]

Melatonin (Mel) is recognized as a prominent plant growth regulator. This study investigated the alleviating effect of Mel pretreatment on growth inhibition caused by low-temperature (LT) stress (10 °C/6 °C) in cucumber seedlings and explored the role of the Ca2+/Calcium-dependent protein kinases (CPKs) signaling pathway in Mel-regulated LT tolerance. The main results are as follows: compared to LT treatment alone, 100 μM Mel increased both the content of Ca2+ (highest about 42.01%) and the expression levels of Ca2+ transporter and cyclic nucleotide-gated channel (CNGC) genes under LT. Similarly, Mel enhanced the content of CPKs (highest about 27.49%) and the expression levels of CPKs family genes in cucumber leaves under LT. Additionally, pretreatment with 100 μM Mel for three days strengthened the antioxidant defense and photosynthesis of seedlings under LT. Genes in the ICE-CBF-COR pathway and the MAPK cascade were upregulated by Mel, with maximum upregulations reaching approximately 2.5-fold and 1.9-fold, respectively, thus conferring LT tolerance to cucumber seedlings. However, the above beneficial effects of Mel were weakened by co-treatment with calcium signaling blockers (LaCl 3 or EGTA) or CPKs inhibitors (TFP or W-7), suggesting that the Ca2+/CPKs pathway is involved in the Mel-mediated regulation of LT tolerance. In conclusion, this study revealed that Mel can alleviate growth inhibition in cucumber seedlings under LT stress and demonstrated that the Ca2+/CPKs signaling pathway is crucial for the Mel-mediated enhancement of LT tolerance. The findings hold promise for providing theoretical insights into the application of Mel in agricultural production and for investigating its underlying mechanisms of action. • Melatonin alleviated low-temperature stress in cucumber by enhancing antioxidant defense and photosynthetic performance. • Melatonin upregulated key genes in the ICE-CBF-COR and MAPK pathways. • Melatonin raised Ca2+ and CPKs, enabling cucumber's low-temperature tolerance through the Ca2+/CPKs pathway. [ABSTRACT FROM AUTHOR]

Copper (Cu) toxicity in crops is a result of excessive release of Cu into environment. Little is known about mitigation of Cu toxicity through the application of carbon-based nanomaterials including water-soluble fullerene C 60 derivatives. Two derivatives of fullerene were examined: polyhydroxylated C 60 (fullerenol) and arginine C 60 derivative. In order to study the response of Cu-stressed plants (Cucumis sativus L.) to these nanomaterials, metabolomics analysis by gas chromatography-mass spectrometry (GC-MS) was performed. Excess Cu (15 μM) caused substantial increase in xylem sap Cu, retarded dry biomass and leaf chlorosis of hydroponically grown cucumber. In Cu-stressed leaves, metabolomes was disturbed towards suppression metabolism of nitrogen (N) compounds and activation metabolism of hexoses. Also, upregulation of some metabolites involving in antioxidant defense system, such as ascorbic acid, tocopherol and ferulic acid, was occurred in Cu-stressed leaves. Hydroponically added fullerene adducts decreased the xylem sap Cu and alleviated Cu toxicity with effectiveness has been most pronounced for arginine C 60 derivative. Metabolic responses of plants subjected to high Cu with fullerene derivatives were opposite to that observed under Cu alone. Fatty acids up-regulation (linolenic acid) and antioxidant molecules (tocopherol) down-regulation might indicate that arginine C 60 adduct can alleviate Cu induced oxidative stress. Although fullerenol slightly improved cucumber growth, its effect on metabolic state of Cu-stressed plants was not statistically significant. We suggest that tested fullerene C 60 adducts have a potential to prevent Cu toxicity in plants through a mechanism associated with their capability to restrict xylem transport of Cu from roots to shoot, and to maintain antioxidative properties of plants. • Excess copper decreased dry biomass and induced chlorosis of cucumber plants. • Leaf metabolism of nitrogen compounds and hexoses was disturbed by high copper. • Arginine C 60 derivative alleviated copper toxicity more effective than fullerenol. • Cucumber metabolic responses induced by arginine C 60 and copper were opposite. • Most restricted xylem transport of copper was observed in arginine C 60 treatment. [ABSTRACT FROM AUTHOR]