Search Results (307)

Cucumbers (Cucumis sativus L.) are highly sensitive to cold, but grafting onto cold-tolerant rootstocks can enhance their low-temperature resilience. This study investigates the physiological and molecular mechanisms by which exogenous vitamin C (Vc) mitigates cold stress in grafted cucumber seedlings. Using cucumber ‘Chiyu 505’ as the scion and pumpkin ‘Chuangfan No.1’ as the rootstock, seedlings were grafted using the whip grafting method. In the third true leaf expansion stage, seedlings were foliar sprayed with Vc at concentrations of 50, 100, 150, and 200 mg L⁻¹. Three days after initial spraying, seedlings were subjected to cold stress (8 °C) for 3 days, with continued spraying. After that, morphological and physiological parameters were assessed. Results showed that 150 mg L⁻¹ Vc treatment was most impactive, significantly reducing the cold damage index while increasing the root-to-shoot ratio, root vitality, chlorophyll content, and activities of antioxidant enzymes (SOD, POD, CAT). Moreover, this treatment enhanced levels of soluble sugars, soluble proteins, and proline compared to control. However, 200 mg L⁻¹ treatment elevated malondialdehyde (MDA) content, indicating potential oxidative stress. For transcriptomic analysis, leaves from the 150 mg L⁻¹ Vc and CK treatments were sampled at 0, 1, 2, and 3 days of cold stress. Differential gene expression revealed that genes associated with photosynthesis (LHCA1), stress signal transduction (MYC2-1, MYC2-2, WRKY22, WRKY2), and antioxidant defense (SOD-1, SOD-2) were initially up-regulated and subsequently down-regulated, as validated by qRT-PCR. Overall, we found that the application of 150 mg L⁻¹ Vc enhanced cold tolerance in grafted cucumber seedlings by modulating gene expression networks related to photosynthesis, stress response, and the antioxidant defense system. This study provides a way for developing Vc biostimulants to enhance cold tolerance in grafted cucumbers, improving sustainable cultivation in low-temperature regions. Full article

The combined effect of non-thermal plasma (NTP) and hydropriming on the germination performance and seedling characteristics of specific varieties of cucumber (Cucumis sativus L.) and broccoli (Brassica oleracea var. italica Plenck.) seeds after short-term storage is reported. Seeds were treated with NTP for 10 and 15 min, followed by hydropriming in distilled water for 24 h, and then stored for six months in the dark before evaluation. The treated cucumber seeds demonstrated a statistically significant enhancement in seed germination and seedling vitality indices. In contrast, broccoli seeds showed no significant improvement. The stimulatory effects observed in cucumber may be attributed to reactive oxygen and nitrogen species, which act as signaling molecules to promote stress tolerance and early growth. This study also highlights the potential of combined NTP treatment and hydropriming as a pre-sowing treatment for select crops, underscoring the need for species-specific optimization. The used, portable, and relatively inexpensive NTP device offers practical advantages for agricultural applications. Full article

Background: The short strand-related sequence (SRS) gene family is a class of plant-specific transcription factors related to a group of genes known as the short internode (SHI) or SRS/STY gene family, which plays important roles in regulating plant growth and development and stress responses. Although the SRS genes have been studied in many plants, in cucurbit crops, they have thus far only been identified in cucumber. Methods: In the Cucurbitaceae database from melon (Cucumis melo), cucumber (Cucumis sativus), watermelon (Citrullus lanatus), bottle gourd (Lagenaria siceraria), wax gourd (Benincasa hispida), moschata pumpkin (Cucurbita moschata), and pumpkin (Cucurbita maxima), a total of 60 SRS genes were identified in seven Cucurbitaceae crops, which were classified into three subfamilies. Results: The same subfamily showed conserved motifs and gene structures. The differences in the number of SRS genes in different Cucurbitaceae crops implied likely gene loss or duplication events during evolution. Analysis of promoter cis-regulatory elements indicated that these SRS genes may be involved in hormone response, growth and development, and biotic and abiotic stress responses in plants. Most of the CmSRS genes in melons were expressed in the roots, with a few expressed in the leaves and ovaries. In addition, CmSRS expression was induced by biotic (wilt and powdery mildew) and abiotic (drought and salt) stresses. Subcellular localization of CmSRS proteins showed predominant expression in the nucleus. Conclusions: A total of 60 Cucurbitaceae SRS genes are present in the genomes of seven Cucurbitaceae crops. These cucurbit SRS genes seem to have maintained similar characteristics and functions during the evolutionary process. These results lay the foundation for the study of biological functions of SRS genes in Cucurbitaceae crops. Full article

Powdery mildew caused by Sphaerotheca fusca poses a significant threat to cucumber (Cucumis sativus L.) production worldwide, underscoring the need for sustainable disease management strategies. This study investigates the potential of L-lysine, abundantly produced by Bacillus subtilis M 320 (BSM320), to prime systemic acquired resistance (SAR) pathways in cucumber plants. Liquid chromatography–mass spectrometry analysis identified L-lysine as the primary bioactive metabolite in the BSM320 culture filtrate. Foliar application of purified L-lysine significantly reduced powdery mildew symptoms, lowering disease severity by up to 92% at concentrations ≥ 2500 mg/L. However, in vitro spore germination assays indicated that L-lysine did not exhibit direct antifungal activity, indicating that its protective effect is likely mediated through the activation of plant immune responses. Quantitative reverse transcription PCR revealed marked upregulation of key defense-related genes encoding pathogenesis-related proteins 1 and 3, lipoxygenase 1 and 23, WRKY transcription factor 20, and L-type lectin receptor kinase 6.1 within 24 h of treatment. Concurrently, salicylic acid (SA) levels increased threefold in lysine-treated plants, confirming the induction of an SA-dependent SAR pathway. These findings highlight L-lysine as a sustainable, residue-free priming agent capable of enhancing broad-spectrum plant immunity, offering a promising approach for amino acid-based crop protection. Full article

Light-harvesting chlorophyll a/b-binding (Lhc) proteins are integral membrane proteins that bind to pigment molecules, playing a critical role in photosynthetic processes, including light energy harvesting and transfer. To investigate the role of the Lhc gene family in cucumber (Cucumis sativus L), genome-wide identification of CsLhc gene family members and analysis of their regulatory networks were carried out using bioinformation and molecular biology research methods at Anhui Science and Technology University. The results indicated that the Lhc family consisted of 21 members, being categorized into five subfamilies: Lhca, Lhcb, CP24, CP26, and CP29. The gene structure and motifs within each subfamily are generally conserved. CsLhcs are distributed on seven chromosomes, including one pair of tandem duplicates and two pairs of segmental duplicates. Six CsLhcs exhibit eight linear relationships with seven AtLhcs, and one CsLhc shows a syntenic relationship with one OsLhc. Analysis of the cis-acting elements in CsLhc promoters revealed their potential involvement in stress responses. Transcriptome data indicated that CsLhcs are minimally expressed in male flowers and roots, but highly expressed in other organs. Analysis of stress response processes revealed that all Lhc genes participate in at least one stress response. Five Lhc genes were confirmed to appear to have expression change using qPCR analysis under high temperature and salt stress. Particularly, under downy mildew, root-knot nematode stresses, and blight stress, up-regulated Lhc genes were the most abundant ones, indicating that the Lhc family acts as a significant role in the growth and development of cucumber. These results provide valuable insights for further understanding the characteristics of the CsLhc family and analyzing the function of the Lhc family in cucumber resistance to biotic/abiotic stresses and in molecular breeding. Full article

Beneficial interactions between plants and bacteria are crucial in agricultural practices, as bacteria can improve soil fertility, promote plant growth, and protect plants from pathogens. This study aimed to molecularly identify and characterize soil bacterial isolates and evaluate their effect on the growth of maize (Zea mays L.), tomato (Solanum lycopersici L.), cucumber (Cucumis sativus L.), and pepper (Capsicum annuum L.) under greenhouse conditions. Plant growth parameters, including plant height, root length, and fresh (FW) and dry (DW) weights, were measured. Additionally, pigment extraction and element content analysis using leaves were performed. Among the isolates, the most effective strain in the greenhouse experiment was Bacillus safensis SCF6, which significantly enhanced plant height and fresh weight across all tested plants, with the greatest influence observed in maize plant height (439.42 ± 6.42 mm), fresh weight (14.07 ± 0.87 g plant⁻¹ FW), and dry weight (1.43 ± 0.17 g plant⁻¹ DW) compared to the control (364.67 ± 10.33 mm, 9.20 ± 1.16 g plant⁻¹ FW, and 0.92 ± 0.15 g plant⁻¹ DW, respectively). Other strains also demonstrated notable results, with Microbacterium testaceum SCF4, Bacillus mojavensis SCF8, and Pseudomonas putida SCF9 showing the highest plant growth-promoting effects on pepper, tomato, and cucumber, respectively. Pseudomonas putida SCF9 demonstrated strong antifungal activity against Monilinia laxa, with a percentage of mycelial growth inhibition (PGI) of 72.62 ± 2.06%, while Bacillus subtilis SCF1 exhibited effects against Botrytis cinerea (PGI = 69.57 ± 4.35%) and Cercospora sp. (PGI = 63.11 ± 1.12%). The development and application of beneficial bacterial inoculants or their formulated products can contribute to environmentally friendly farming practices and global food security. Full article

Invasive alien species are one of the main threats to global biodiversity, and pose significant management challenges in several areas outside their natural range. In southern Mediterranean Europe, the invasion of Acacia species is particularly severe and its control requires costly and often ineffective actions. The use of vermicompost derived from these species to replace peat-based substrates in horticulture offers a promising alternative to mitigate their economic and environmental impacts while enhancing the sustainability of their control. This study explored the potential of vermicompost produced from the fresh aboveground waste biomass (leaves + stems + flowers) of Acacia dealbata and Acacia melanoxylon (75:25 w/w), two of the most aggressive Acacia species in the Mediterranean, using Eisenia fetida over twelve weeks. In essence, this study aimed to evaluate the quality of the produced vermicompost and its suitability as a partial substitute for potting substrate in the production of cucumber (Cucumis sativus) seedlings for transplant. Four substrate mixtures containing 0%, 10%, 30%, and 50% of Acacia vermicompost (w/w), combined with commercial peat-based potting substrate and perlite (20%) were tested in polystyrene seedling trays. Seedling emergence, growth, and leaf biochemical parameters (photosynthetic pigments, phenolics, soluble sugars and starch, and total thiobarbituric acid-reactive substances—TBARSs) were evaluated. The results showed that the addition of Acacia vermicompost to the commercial substrate did not affect its germination but significantly enhanced seedling growth, particularly in mixtures containing 30% and 50% Acacia vermicompost. In addition, the absence of accumulation of TBARSs also reflected the superiority of these two treatments. These findings suggest that vermicompost derived from A. dealbata and A. melanoxylon biomass can be a viable peat-based substrate alternative for horticultural production, with the dual benefit of promoting sustainable agricultural practices and contributing to invasive species management. Full article

Plant U-box (PUB) E3 ubiquitin ligases have undergone significant expansion compared to their fungal and animal counterparts. These E3 ligases play critical roles in diverse biological processes, including responses to biotic and abiotic stresses. However, systematic identification of PUB genes in cucumber (Cucumis sativus L.) has been lacking, and their expression and functional characterization remain largely unexplored. Leveraging the recently released near-complete cucumber genome, we identified 53 putative PUB proteins classified into eight distinct groups based on domain architecture. The molecular weights of CsPUBs range from 26 to 166 kilodaltons (kDa). Exon numbers in CsPUB genes vary substantially, with CsPUB48 containing a maximum of 17 exons, while 18 CsPUB genes harbor only a single exon. Chromosomal distribution of CsPUBs is uneven, with Chr 3 harboring the highest density (12 genes) and Chr 7 the lowest (1 gene). Notably, tandem duplications (e.g., CsPUB29-CsPUB36 and CsPUB18-CsPUB49) and seven collinear gene pairs were identified, suggesting evolutionary diversification. Promoter regions of CsPUBs are enriched with cis-regulatory elements linked to plant growth and development, phytohormone, stress responses, light, and so on, implying their regulatory roles in various biological processes. Expression profiling revealed tissue-specific patterns and differential regulation of multiple CsPUBs under stress conditions. Subcellular localization studies demonstrated that CsPUBs target diverse organelles, with some localizing to punctate structures potentially representing uncharacterized compartments. Collectively, this systematic analysis establishes a comprehensive framework for understanding particular CsPUB functions. Full article

SABATH methyltransferase can methylate small-molecule metabolites of plants to generate different products, and it plays a crucial role in plant growth and development as well as stress response. In this study, 13 SABATH genes distributed on five chromosomes of cucumbers were identified, and the synergistic effects among their domains, gene structures, conserved motifs, phylogenetic relationships, collinearity analysis, cis-acting elements, expression patterns, and plant growth-promoting rhizosphere bacteria (PGPR) were analyzed. The gene structure and conserved motifs of the same group of CsSABATH have similar intron numbers and conserved motifs. We detected 10 cis-elements in the promoter of the CsSABATH gene, indicating that they may be involved in different signaling pathways. qRT-PCR revealed the tissue-specific, drought and salt stress-responsive expression of the SABATH gene in cucumbers. Furthermore, we also verified that the expression level of CsaV3_6G046510 after inoculation with PGPR-GD17 bacteria under drought and salt stress was significantly lower than normal drought and salt dress, indicating that this gene may respond to PGPR and in abiotic stress play an important role. This study provides valuable insights into the molecular characteristics and evolutionary history of the SABATH gene family in cucumbers, laying a foundation for further analysis of the function of the CsSABATH gene in cucumbers. Full article

Root-knot nematodes (RKNs), specifically Meloidogyne incognita, are notoriously difficult to eliminate as endophytic nematodes, and cause severe damage to various plants. Cucumber (Cucumis sativus), which is a cash crop widely grown across the world, is often infected by RKNs. ELONGATED HYPOCOTYL5 (HY5), a member of the bZIP transcription factor family, plays a vital role in hormone, nutrient, abiotic stress, biotic stress, and oxygen species (ROS) signaling pathways. However, the involvement of HY5 in the defense against RKNs has rarely been reported. The present study initially explored the response of CsHY5 to RKNs. The results indicated that the hy5 mutant had a higher number of nematodes and galls in the root system and exhibited a higher susceptibility to RKNs compared with the wild type (WT). Particularly, the root-knot nematodes in hy5 plants completed their life cycle more quickly and produced more eggs. The activities of defense-related hormones and antioxidant enzymes were measured, and the results indicated that JA, jasmonoyl-isoleucine (JA-Ile), abscisic acid (ABA), peroxidase (POD), and ascorbate peroxidase (APX) were significantly elevated in the wild type, but were not induced or decreased in the mutant. Through transcriptome sequencing analysis and quantitative real-time PCR (qRT-PCR), it was found that when RKNs infect plants, the key genes of jasmonic acid (JA) synthesis, CsAOC and CsAOS, as well as the key gene of the antioxidant system, CsPOD, were all significantly induced. Nevertheless, this induction effect disappeared in the hy5 mutant. Generally, CsHY5 plays a role in the response of cucumber to RKNs, and its deletion increases the sensitivity of cucumber to RKNs. These results suggest that CsHY5 may affect the resistance of cucumber to RKNs by affecting antioxidant enzyme activities and hormone content. Full article

Cucumber (Cucumis sativus) is an economically important vegetable but powdery mildew (caused by Podosphaera xanthii) limits cucumber production. The WALLS ARE THIN1 (WAT1) gene is crucial for regulating secondary cell wall thickness and is pivotal in plant immune responses. However, the role of WAT1 in cucumber defense against P. xanthii remains poorly characterized. In this study, we identified 47 CsWAT1 genes in the C. sativus genome and classified them into five clusters. Comprehensive analyses of the chromosome location, gene structure, and protein motifs revealed both conserved evolutionary and functional characteristics across plant species, as well as novel features specific to cucumber. Promoter analysis suggested that nine CsWAT1 genes may participate in the cucumber response to P. xanthii stress. Further expression profiling and functional analysis indicated that CsWAT1-20 positively regulates cucumber defense against P. xanthii stress. Our results provide fundamental insights into the characterization of CsWAT1 genes and the function of CsWAT1-20 in P. xanthii defense, laying the groundwork for further studies on the roles of the CsWAT1 gene family in cucumber plants. Full article

Cucumber (Cucumis sativus) greenhouse cultivation offers higher yields and quality compared to open-field systems, but success depends on balanced fertilization. This study compared chemical and biol (liquid organic fertilizer) treatments on cucumber yield, fruit number, and size (Centauro 1 variety). Four treatments—Biol30 (3% biol), Biol70 (7% biol), Nitro (urea), and Comp (complete chemical fertilization)—were applied in a randomized design. Results indicated no statistically significant differences in yield among treatments (p = 0.094), yet Biol70 outperformed Nitro and Comp by 1.44× and 1.18×, respectively. Notably, Nitro produced the largest and heaviest fruits but the lowest fruit count, while organic treatments (Biol30 and Biol70) demonstrated comparable fruit quality and higher yields. The Biol70 treatment, in particular, highlighted the potential of biol as a sustainable alternative, achieving yields of 272.59 kg total production and 34.07 kg per bed, with fruit weights averaging 0.4309 kg and lengths of 26.511 cm. These findings underscore the viability of biol, especially at higher concentrations, as an eco-friendly substitute for chemical fertilizers, aligning with global efforts to promote sustainable agricultural practices. Full article

The auxin efflux transporter PIN protein plays a crucial role in the asymmetric distribution of auxin on the plasma membrane, influencing the growth and development of plant organs. In this study, we identified nine members of the PIN gene family in the cucumber genome, which could be classified into five phylogenetic groups. These genes have diverse structures but conserved transmembrane domains. Analysis of cis-acting elements in the promoters revealed that CsPINs contain 48 types of cis-acting elements, predominantly light-responsive elements and plant hormone response elements. In addition, PIN proteins may interact with a variety of auxin-related proteins (including auxin response factor, auxin binding protein, mitogen-activated protein kinase PINOID, etc.) to jointly regulate the auxin synthesis and metabolic pathways. We analyzed the expression profiles of PIN genes in 23 tissues of cucumber using the CuGenDB database, and further investigated the expression levels of PIN genes in leaves and roots in response to different abiotic stresses and hormone treatments by qRT-PCR. This study provides a theoretical basis for clarifying the regulatory mechanism of the cucumber PIN gene family during environmental stress processes. Full article

Xishuangbanna cucumber (Cucumis sativus L. var. xishuangbannanesis), as a rare and endangered cucumber germplasm resource, possesses certain irreplaceable characteristics that make it difficult to reacquire once lost. To ensure long-term preservation of this germplasm, immediate propagation and regeneration are required after successful collection. Current germplasm management relying on conventional viability testing methods often leads to seed loss. Therefore, there is an urgent need to develop a rapid and non-destructive testing technology for assessing the seed viability of Xishuangbanna cucumber. This study integrated hyperspectral imaging technology with various data preprocessing methods, feature wavelength selection algorithms, and classification models to achieve rapid and non-destructive detection of Xishuangbanna cucumber seed viability. Hyperspectral imaging was employed to acquire spectral data from the seeds. Preprocessing methods including MSC (Multivariate Scattering Correction), SNV (Standard Normal Variety), FD (First Derivative), SD (Second Derivative), and L2NN (L2 Norm Normalization) were applied to enhance spectral data quality. Feature selection algorithms such as UVE (Uninformative Variables Elimination), SPA (Successive Projections Algorithm), and CARS (Competitive Adaptive Reweighted Sampling) were utilized to identify optimal spectral bands. Combined with KNN (K-Nearest Neighbor) and LogitBoost algorithms, predictive models for seed viability were established. The results demonstrated that the L2NN-KNN model outperformed other models, achieving an accuracy of 83.33%, precision of 86.99%, and an F1-score of 0.83. This study confirms that hyperspectral imaging combined with machine learning can effectively predict the viability of Xishuangbanna cucumber seeds, providing a novel technical approach for the conservation of rare and endangered cucumber germplasm resources. The findings hold significant implications for promoting long-term preservation and sustainable utilization of this valuable genetic material. Full article

Squash leaf curl China virus (SLCCNV) belongs to the species Begomovirus cucurbitachinaense in the genus Begomovirus and can infect some Cucurbitaceae crops except for watermelon (Citrullus lanatus). In this study, watermelon plants showing symptoms typical to begomovirus infection in field were observed in Zhejiang Province of China, and SLCCNV presence was identified through PCR and next-generation sequencing (NGS). The pairwise sequence identity of the DNA-A genome shows that SLCCNV watermelon isolate belongs to the SLCCNV/CN strain and shares 96% nucleotide identity with the previously sequenced SLCCNV/CN. An infectious clone of SLCCNV watermelon isolate was constructed using the tandem repeat fragment method. Through agrobacterium-mediated inoculation, the clone could induce systemic infection with typical symptoms in watermelon, melon (Cucumis melo), squash (Cucurbita pepo), pumpkin (Cucurbita maxima), wax gourd (Benicasa hispida), cucumber (Cucumis sativus), and N. benthamiana. It was further demonstrated that the progeny virions derived from the cloned watermelon isolate could be transmitted by whitefly rather than the sap. To the best of our knowledge, this is the first report of a natural infection of SLCCNV on watermelon in China, and the first complete report on the molecular characteristics and pathogenicity of watermelon-infecting SLCCNV in the world. Full article