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Abstract Background BAK1 (Brassinosteroid insensitive 1-associated receptor kinase 1) plays an important role in disease resistance in plants. However, the function of BAK1 family in cucumber and the decisive genes for disease-resistance remain elusive. Results Here, we identified 27 CsBAK1s in cucumber, and classified them into five subgroups based on phylogenetic analysis and gene structure. CsBAK1s in the same subgroup shared the similar motifs, but different gene structures. Cis-elements analysis revealed that CsBAK1s might respond to various stress and growth regulation. Three segmentally duplicated pairwise genes were identified in cucumber. In addition, Ka/Ks analysis indicated that CsBAK1s were under positive selection during evolution. Tissue expression profile showed that most CsBAK1s in Subgroup II and IV showed constitutive expression, members in other subgroups showed tissue-specific expression. To further explore whether CsBAK1s were involved in the resistance to pathogens, the expression patterns of CsBAK1s to five pathogens (gummy stem blight, powdery mildew, downy mildew, grey mildew, and fusarium wilt) reveled that different CsBAK1s had specific roles in different pathogen infections. The expression of CsBAK1-14 was induced/repressed significantly by five pathogens, CsBAK1-14 might play an important role in disease resistance in cucumber. Conclusions 27 BAK1 genes were identified in cucumber from a full perspective, which have important functions in pathogen infection. Our study provided a theoretical basis to further clarify the function of BAK1s to disease resistance in cucumber.

Smart horticulture aims to use the emerging technologies to modernise industrial applications and address issues such as productivity, environmental sustainability, and food security. In recent years, scientists have made significant efforts to design the novel methods for horticultural applications with using nanoparticles (NPs) and their composites. The use of silver nanoparticles (Ag-NPs) as growth-modulating and antipathogen agents in horticulture is a promising area of research. However, the current state of knowledge in these fields is still insufficient.The study aimed to assess the impact of alginate gels containing Ag-NPs on the germination of cucumber (Cucumis sativus L.) seeds and the initial growth stage of seedlings. Composites with Ag-NPs were prepared using chemical synthesis, with maltose as the reducing substance and biodegradable polymer, sodium alginate, as the stabilizer. Blotting paper was used to place cucumber seeds on dishes. The seeds were then soaked with diluted test solutions containing Ag-NPs (10 ppm and 20 ppm), as well as treatments with deionized water (negative control) and aqueous sodium alginate solutions (1:5 and 1:10) without silver nanoparticles (positive control). After 8 days, the germination, morphological and biochemical parameters were determined. Seed germination percentage was not affected by alginate gels and 10 ppm Ag-NPs. At a concentration of 20 ppm, Ag-NPs reduced the germination index,as well as length and weight of the root, stem, seedling, when compared to the positive and negative control. The inhibition coefficients for root, stem, and seedling were significantly higher in the treatment group. The application of Ag-NPs at concentrations of 10 and 20 ppm resulted in a decrease in the total antioxidant capacity (TAC), total phenolics (TP), and malondialdehyde (MDA) content in seedling roots compared to the negative control. However, there was an increase in TAC and TP in shoots, but not in MDA. In the roots of the seedlings, the application of Ag-NPs resulted in an increase in catalase (CAT) activity, while ascorbate peroxidase (APX), guaiacol peroxidase (GPX), and superoxide dismutase (SOD) activity was decreased compared to the negative control. In the shoots of the seedlings, CAT, GPX, and SOD activity was higher than in the plant material from the positive control. The application of Ag-NPs had a significant, dose-dependent effect on the investigated parameters of cucumber seedlings. However, it was also observed that sodium alginate without NPs had an impact. Ag-NPs elicit a stronger response in shoot tissues, as reflected by higher TAC and content of TP and MDA, although CAT, GPX, and SOD activity was lower than in roots Composites of sodium alginate with Ag-NPs can be used to shape of cucumber seedling germination performance.

Objectives: Cucumis sativus L. (C. sativus) is vegetable commonly used for managing blood pressure and often consumed in combination with standard antihypertensive therapy, despite lack of scientific evidence supporting their use. Combination of herbs and standard medication could have positive or negative effects. Therefore, this study aimed to evaluate the antihypertensive activity of C. sativus and the combined effect with losartan in the hypertensive rat model induced by angiotensin II. Angiotensin II is a component of the renin-angiotensin-aldosterone system that, upon binding to its receptor, constricts blood vessels leading to elevation of blood pressure. Methods: In an antihypertensive study, rats received C. sativus orally at doses of 9, 18, 27, and 36 mg/kg (full dose); while in a combination study, animals received losartan 2.25 mg/kg combined by either with C. sativus 9 or 18 mg/kg. The standards group received losartan 2.25 mg/kg or 4.5 mg/kg (full dose). Results: Blood pressure was measured using the tail-cuff method. C. sativus significantly attenuated angiotensin II-induced hypertension as observed in groups receiving C. sativus at 9, 18, 27, and 36 mg/kg at 30 minutes after induction showed the average change (Δ) of systolic blood pressure (SBP) and diastolic blood pressure (DBP) with respect to time zero were 28.8/18.3, 24.8/15.8, 22.8/15.5, and 11.5/9.0 mmHg, respectively. Whereas the average change (Δ) of SBP and DBP in the rats receiving the combination of half doses of C. sativus and losartan were 8.8/9.0 mmHg, respectively. These diminished effects were better than a full dose of C. sativus and comparable with a full dose of losartan (6.5/7.8 mmHg). Conclusion: The present findings indicate that C. sativus dose-dependently blocks blood pressure elevation induced by angiotensin II. The combination of half dose of C. sativus and losartan has an additive effect in lowering blood pressure.

Nitrogen-fixing cyanobacterial consortia are an alternative to the indiscriminate use of chemical fertilizers that affect the environment, fix atmospheric nitrogen, and can therefore be used as plant growth promoters, synthesize various substances such as auxins, vitamins, and total proteins, and fix atmospheric biofertilizers and soil conditioners. The present study aimed to obtain and develop, by biotechnological means, two consortia of cyanobacteria isolated from the root and rhizosphere of Carica papaya grown in sandy loam soil. The culture was carried out in Blue Green Medium without modified nitrogen (BG110), with aeration of 0.32 L min−1, at a light intensity of 48.83 μEm−2s−1, and a temperature of 22 ± 2 °C. Two consortia consisting of Nostoc commune, Aphanothece minutissima, Planktothrix sp. (C1), Nostoc commune, Calothrix sp., and Aphanothece minutissima (C2) were isolated and morphologically identified. The effective development of these consortia was verified at the laboratory level by obtaining biomass in dry weight as well as photosynthetic pigments, proteins, carbohydrates, and lipids. Germination parameters were determined in seeds of Cucumis sativus L. var. Market plus treated with the nitrogen-fixing cyanobacteria consortia, obtaining a higher germination percentage (>90%), greater root length (>6 cm), and higher vigour index I (513), II (13.02) for the C2 consortium. This broadens the spectrum of rhizosphere-derived microorganisms with potential as growth biostimulators.

Due to the widespread use of intensive cropping patterns, the problem of continuous cropping obstacle, which is dominated by autotoxicity, has been becoming more and more prominent. Although many methods have been proposed to overcome the continuous cropping obstacle of cucumber, no study has reported the screening and evaluation of cucumber germplasm resistant to autotoxicity. In this study, 28 physiological indices related to the cucumber bud stage under cinnamic acid (CA) treatment were determined. In total, 45 cucumber cultivars were classified into three groups using principal component analysis and cluster analysis, and a model for evaluating cucumber resistance to autotoxicity was developed. The evaluation model was validated using autotoxicity-tolerant and non-autotoxicity-tolerant cultivars. The results showed that the growth of non-autotoxicity-tolerant cultivars was significantly inhibited compared to autotoxicity-tolerant cultivars. This indicated that the evaluation model of cucumber autotoxicity tolerance is reliable. The results of this study provide a valuable reference for the application of cucumber autotoxicity-tolerant germplasm resources and the development of autotoxicity-tolerant genes.

Background: Calcium nitrate is a widely used fertilizer in the preparation of nutrient solutions. However, there is still a need to determine the effects of different levels of calcium nitrate on the Persian cucumber crop to optimize fertilization practices and improve crop yield. Objective: To determine the effects of two levels of calcium nitrate in the nutrient solution on the growth, yield, and nutrient content of two Persian cucumber hybrids (Bereket and Cruz). Methodology: The experiment was carried out in a completely randomized design in a factorial arrangement (two hybrids and two nutrient solutions) under greenhouse conditions. Results: The nutrient solution with 11 meq L-1 of calcium nitrate increased the concentration of nitrate and calcium in the petiole sap of the Cruz hybrid in the flowering stage; however, the yield of both hybrids decreased. On the other hand, the nutrient solution with 9 meq L-1 of calcium nitrate increased the number of fruits of both hybrids and the yield per plant of the Cruz hybrid. Implications: The Cruz hybrid showed to be more efficient in calcium uptake than the Bereket hybrid, which is interesting since it could require less calcium application without affecting yield. However, other studies are necessary to expand this information. Conclusion: The nutrient solution containing 9 meq L-1 of calcium nitrate showed a significant increase in the number of fruits per plant for both the Cruz and Bereket hybrids. This highlights the importance of appropriate calcium nitrate supplementation in the nutrient solution, as it enhances the production of hydroponically grown Persian cucumbers.

Soluciones nutritivas con balance en las relaciones, proporciones y concentraciones de los iones optimizan la eficiencia en el uso de nutrimentos y el rendimiento de los cultivos. El objetivo de este trabajo fue evaluar, en invernadero, tres relaciones porcentuales Mg2+/cationes (20, 40 y 60/100) y tres de NO3-/aniones (40, 60 y 80/100) y su combinación sobre la composición mineral, la eficiencia de uso de nutrimentos (EUN) y el rendimiento de pepino (Cucumis sativus cv. Poinsett 76) desarrollado en hidroponía en circuito cerrado. El diseño experimental fue completamente al azar con arreglo factorial de tratamientos 32 y seis repeticiones. Las variables evaluadas fueron la composición mineral de hojas, tallos y frutos, EUN, peso, diámetro, longitud, número, y rendimiento de fruto. Los resultados se analizaron con ANDEVA y los promedios se compararon con la prueba de Tukey (P ≤ 0.05). El rendimiento superior fue con la combinación 20/100 Mg2+ y 60/100 NO3-, relaciones mayores de Mg2+ (40 y 60/100) y de NO3- (80/100) redujeron el rendimiento 33.4%, 30.7% y 20.6%, respectivamente, y disminuyeron la eficiencia de Mg y N, respecto a 20/100 Mg2+ y 60/100 NO3-. La relación 60/100 Mg2+ aumentó la concentración nutrimental de Mg en los frutos, pero disminuyó el rendimiento.

The application of oligosaccharides can promote plant growth by increasing photosynthesis or inducing plant innate immunity. However, the mechanisms by which oligosaccharides affect bacterial community diversity and abundance remain unclear. In this study, a mixed oligosaccharide was applied to the growth of cucumbers. The findings of the present study suggest that the application of MixOS has significant effects on the bacterial communities in the phyllosphere, rhizosphere, and bulk soil of cucumber plants. The treatment with MixOS resulted in delayed senescence of leaves, well-developed roots, and higher fruit production. The bacterial diversity and composition varied among the different ecological niches, and MixOS application caused significant shifts in the bacterial microbiome composition, particularly in the phyllosphere. Moreover, mixed oligosaccharides increased the abundance of potential growth-promoting bacteria such as Methylorubrum spp. and Lechevalieria spp., and more zOTUs were shared between the WM and MixOS treatments. Furthermore, the bacterial co-occurrence network analysis suggested that the modularity of the phyllosphere networks was the highest among all samples. The bacterial co-occurrence networks were altered because of the application of MixOS, indicating a greater complexity of the bacterial interactions in the rhizosphere and bulk soil. These findings suggest that mixed oligosaccharides has the potential to improve plant growth and yield by modulating the bacterial communities within and outside the plants and could provide a theoretical basis for future agricultural production.

Countries in arid climates, such as Qatar, require efficient water-saving strategies and nitrogen treatment for vegetable production. Vegetable importation constituted approximately USD 352 million of Qatar’s 2019 GDP; hence, enhancing local production is essential. This study investigated the effect of varying nitrogen and water levels on cucumber (Cucumis sativus L.) fruit yield. Various water management strategies were also evaluated. A split plot design was employed with two water levels (W1: 50% deficit irrigation, W2: 100% full irrigation) and three nitrogen levels (N1: 50 kg N ha−1, N2: 70 kg N ha−1, N3: 100 kg N ha−1) to examine cucumber yield and physiological response. Our findings revealed that using minimal drip irrigation and reducing nitrogen levels significantly enhanced the growth, SPAD index, fruit characteristics, and yield components of cucumber. Drip irrigation had a greater influence on cucumber production than nitrogen levels. Shoot height increased by 4% from W2N1 (T1) to W1N3 (T6) and 4.93% from W2N2 (T2) to W1N2 (T5). Fruit length and width increased by 10.63% and 13.41% from T2 and T1 to T5, respectively. The highest total yield occurred at T5, followed by T6, T2, W2N3 (T3), W1N1 (T4), and T1 at 34.5, 29.1, 27.6, 25.8, 25.2, and 20.4 t/ha, respectively. The optimal combination comprised 50% deficit irrigation (W1) and 70 kg N ha−1 (N2) nitrogen. These results suggest the importance of optimizing drip irrigation for achieving maximum cucumber fruit yield in arid climates.

Plant endophytic fungi and rhizosphere soil fungi are often reported as biocontrol agents against plant pathogens or with plant growth promotion potential. Four treatments were performed in field and greenhouse experiments where cucumber plants were inoculated with Trichoderma harzianum and Fusarium oxysporum in 2022. The roots, stems and leaves of cucumber plants and their rhizosphere soil were collected twice individually from the field and greenhouse for isolation of cucumber endophytic and rhizosphere soil fungi. All fungal strains were identified through sequence similarity of the ITS1-5.8s-ITS2 rDNA region. The potato dextrose agar (PDA) media yielded the highest number of genera isolated from cucumber plants, rhizosphere soil and both compared to other media. There were no significant differences among the four media for the isolation of all cucumber endophytic fungi. However, in the roots, the number of endophytic fungi isolated by MRBA was significantly higher than that isolated on malt extract agar (MEA), while in the stems, the number of fungi isolated with PDA was significantly higher than that isolated with Martin’s rose bengal agar medium (MRBA). PDA had significantly higher isolation efficiency for the rhizosphere soil fungi than MRBA. The 28 fungal genera had high isolation efficiency, and the endophytic Trichoderma strains were significantly more isolated by MEA than those of MRBA. It is suggested that PDA can be used as a basic medium, and different cultural media can be considered for specific fungal genera.

This study aimed to evaluate the effects of the protein hydrolysate Naturamin WSP on the antioxidant defense system and oxidation-related damage of young cucumber plants exposed to chilling stress. Low positive temperatures have a negative effect on plant growth and performance, and besides visible alterations, such as inhibited growth, significant changes occur at the cellular level. Plants grown at low temperature typically suffer from oxidative damage, which leads to increased lipid peroxidation. Moreover, chilling-stressed plants accumulate more proline to protect their cell membranes. The application of biostimulants such as the protein hydrolysate Naturamin WSP can alleviate some of the adverse effects caused by low temperature. Our results indicated an increased activity of guaiacol peroxidase (GPOD) in all plants treated with the biostimulant regardless of the temperature of cultivation. The mitigation of damages caused by chilling stress might be explained by an enhanced anti-oxidative defense, as demonstrated by the activity of guaiacol peroxidases and increased proline concentrations in Naturamin WSP-treated plants.

Gummy stem blight (GSB), caused by Didymella bryoniae, is one of the most devastating diseases that severely reduces cucumber production. Developing resistant varieties would be an effective strategy to control GSB. Although several GSB-resistant QTLs have been reported, causal genes for GSB resistance have not yet been identified in cucumber. A novel loci gsb3.1 for seedling GSB resistance from the “PI 183967” genotype was previously identified in a 1.7-Mb interval on chromosome 3. In this study, we developed a residual heterozygous line-derived strategy from Recombinant Inbred Lines to perform fine mapping, and with this approach, the gsb3.1 locus was narrowed to a 38 kb interval. There were six predicted genes at the gsb3.1 locus, four of which differed in expression in the GSB-resistant compared to the susceptible lines after fungal inoculation. These candidate genes (Csa3G020050, Csa3G020060, Csa3G020090, and Csa3G020590) within the gsb3.1 locus could be helpful for the genetic study of GSB resistance and marker-assisted selection in cucumber. Phylogenetic analyses indicated that the resistant gsb3.1 allele may uniquely exist in the wild species present in the Indian group, and that nucleotide diversity was significantly reduced in cultivated accessions. Therefore, the gsb3.1 allele could be introgressed into existing commercial cultivars and combined with other resistance QTLs to provide broad-spectrum and robust GSB resistance in cucumber.

Salinity stress prominently limits cucumber growth and productivity. However, the mechanism underlying salinity response mediated by the C-TERMINALLY ENCODED PEPTIDE (CEP) peptide in cucumber primary root remains largely unclear. In this study, we show that salinity prominently inhibits cucumber primary root growth, and CsCEP gene expression is differentially induced by salinity. We further demonstrate that the exogenous application of synthetic CsCEP3 peptide partially suppresses salinity-triggered growth inhibition in cucumber primary root, although CsCEP3 peptide itself shows no obvious effect on cucumber primary root growth under normal conditions. Our transcriptomic and qRT-PCR data further reveal that CsCEP3 peptide may modulate gene expression related to abscisic acid (ABA) signaling pathway, reactive oxygen species (ROS) production, and slat-responsive transcription factors to attenuate the inhibitory effect of salinity on cucumber primary root growth. Taken together, our work provides a fundamental insight into CEP peptide-mediated cucumber salinity adaptation.

Background. One of the global problems presently faced by humanity is obesity and overweight. For treatment and prevention of this disease, doctors recommend consuming more vegetables, cucumbers in particular. Despite the fact that Russia is one of the major cucumber producers, its average yield is more than twice lower than in the EU countries. To meet the demand of the population, it is necessary to additionally import the missing products. In this regard, the urgent need for an increase of cucumber production is obvious, and first of all, by raising the yield.Materials and methods. The research was conducted at the experimental sites of Volgograd Experiment Station of VIR. Accessions from VIR’s cucumber collection served as the material for the study. Methods developed and accepted by VIR were used in the research.Results and conclusions. Such agronomic characteristics as yield, fruit weight and length, thorn color, dry matter and sugar content were studied. A noticeable direct correlation was found between fruit length and fruit weight, and moderate direct correlations were observed between yield and fruit length, yield and fruit weight, dry matter and sugars. The indicators showing suitability of accessions for salting and canning were analyzed. Accessions that can be used in breeding practice are recommended. A conclusion is made about the prospects of breeding for valuable agronomic traits using long-fruited forms of cucumber from the countries of South-East Asia and the Russian Far East.

En sistemas de fertirriego, el manejo adecuado de la nutrición potásica en el cultivo de pepino Persa incrementa la calidad de fruto. De igual manera, conocer los índices de extracción nutrimental son necesarios para establecer programas de nutrición mineral durante el ciclo del cultivo. La presente investigación tuvo como objetivo, evaluar el efecto de la nutrición potásica y cuantificar la extracción nutrimental en dos variedades de pepino Persa (Reehan y Khassib). El diseño experimental fue factorial 2 × 4, el primer factor fue las dos variedades de pepino y el segundo factor la concentración de potasio (K+) en la solución nutritiva, con concentraciones de 5, 7, 9 y 11 meq L-1. Las variables fueron: producción acumulada de fruto (PAF), número de frutos (NF), peso individual de fruto (PIF), diámetro de fruto y sólidos solubles totales (SST). El análisis de varianza indicó que hubo efecto de interacción de factores en las variables de PAF y NF (P ≤ 0.05). En ambas variedades, existieron diferencias significativas en todas las variables de respuesta cuantificadas y se encontró que Khassib tuvo los mayores valores (Tukey, P ≤ 0.05). Para el factor solución nutritiva, sólo hubo diferencias significativas en PAF y PIF. La mayor PAF (Tukey, P ≤ 0.05) se obtuvo con las soluciones nutritivas de K con 9 y 11 meq L-1; mientras que el mayor PIF ocurrió con 5, 7 y 9 meq L-1 de K. La concentración de K en la solución nutritiva tuvo una correlación positiva con el contenido de sólidos solubles totales en frutos de la variedad Reehan (r = 0.999), pero no en la variedad Khassib (r = -0.6829). El requerimiento nutrimental (kg) por tonelada de fruto fresco en Reehan fue N 3.93, P 0.46, K 3.11, Ca 0.79 y Mg 1.30; mientras que en Khassib fue N 5.87, P 0.49, K 3.11, Ca 0.85 y Mg 1.54.

Soil biofumigation is a widely used farming practice for soil-borne disease management in vegetable crops. Soil biofumigation is the practice of the incorporation of fresh plant materials from the members of the Brassicaceae family into the soil which release antimicrobial volatile organic compounds (VOCs), namely glucosinolates and their hydrolysis products. However, the VOCs may affect non-target beneficial soil biota including microbial biocontrol agents (MBAs) due to their broad-spectrum toxicity. In this study, native antagonistic rhizobacteria were isolated from cabbage plants grown in biofumigated fields and their potential in the management of Pythium aphanidermatum cucumber damping-off was evaluated with and also without biofumigation using cabbage leaf residue. A total of 20 morphologically distinct, culturable bacterial strains were recovered from the rhizosphere soil of cabbage cultivated in a biofumigated field, with the largest fraction of the isolates belonging to the genus Bacillus. The other bacterial genera isolated were Pseudomonas, Serratia, Stenotrophomonas, Microbacterium and Priestia. Of the 20 bacterial isolates, Pseudomonas aeruginosa B1-SQU, Pseudomonas indica B2-SQU, Serratia marcescens B3-SQU and Pseudomonas brenneri B4-SQU exhibited inhibitory activity against P. aphanidermatum in a co-culture assay. The deformation and shrinkage of P. aphanidermatum hyphae due to diffusible antimicrobial compounds from these bacterial strains were witnessed through scanning electron microscopy. A biofilm was formed by these bacterial strains in vitro and they exhibited compatibility with each other; however, they had no significant plant growth promotion effect on cucumber. These bacterial strains significantly reduced damping-off in cucumber under greenhouse conditions when applied to soil singly, but failed to show a significant effect when combined with biofumigation treatment, though the bacterial population in the soil was maintained at higher levels. Soil biofumigation alone was also not effective in suppressing the damping-off of cucumber. Gas chromatography–mass spectrometry analysis revealed that 1-butanol, n-butyl butyrate and butyl acetate were the predominant VOCs in the soil amended with cabbage leaf residue. The results suggest that soil biofumigation with cabbage leaf residue has no significant effect on P. aphanidermatum under high inoculum levels; furthermore, it affects the efficiency of the bacterial antagonists in controlling damping-off in cucumber.

Tuz stresi (100 mM NaCl) altındaki hıyar (Cucumis sativus L.) genotipinde (Beith Alpha F1) ekzojen salisilik asit uygulamasının fotosistem II aktivitesi üzerindeki etkileri klorofil a fluoresansı tekniği yardımıyla araştırılmıştır. 10 günlük hıyar fidelerine 100 mM tuza karşı 50 µM salisilik asit 5 gün süreyle uygulanmıştır. 5. günün sonunda yapılan klorofil a fluoresansı ölçümleri değerlendirilmiştir. Tuz stresi hıyar yapraklarında fotosistem II’nin hem donör hem de akseptör bölgesindeki elektron hareketlerini inhibe etmiştir. Ayrıca tuz stresinin hıyar bitkisinde aktif reaksiyon merkezi miktarını ve kinonA ile plastokinonun indirgenme yeteneğini azalttığı, indirgenmiş reaksiyon merkezlerinin birikimini ve ısı enerjisi kaybını artırdığı belirlenmiştir. Salisilik asit uygulaması ise hıyar bitkilerinde tuz stresinin fotosistem II’nin donör ve akseptör bölgesindeki elektron hareketleri üzerindeki olumsuz etkisini ortadan kaldırmıştır. Ek olarak salisilik asit uygulaması hıyar yapraklarındaki aktif reaksiyon merkezi miktarını ve kinonA ile plastokinonun indirgenme yeteneğini artırırken, indirgenmiş reaksiyon merkezi miktarını ve ısı enerjisi kaybını azaltmıştır. Sonuç olarak salisilik asidin hıyar yapraklarında tuz toleransını artırdığı ve bu yaklaşımın tarımsal amaçlarla kullanılabileceği söylenebilir.

Powdery mildew (PM) caused by Podosphaera xanthii poses a continuous threat to the performance and yield of the cucumber (Cucumis sativus L.). Control in the initial stages of infection is particularly important. Here, we studied the differential physiological and transcriptomic changes between PM-resistant strain B21-a-2-1-2 and PM-susceptible strain B21-a-2-2-2 at the early stage of P. xanthii attack. When challenged with P. xanthii, the tolerant line can postpone the formation of the pathogen primary germ. Comparative transcriptomic analysis suggested that DEGs related to the cell wall and to pathogen and hormone responses were similar enriched in both cucumber lines under P. xanthii infection. Notably, the number of DEGs triggered by P. xanthii in B21-a-2-1-2 was quintuple that in B21-a-2-2-2, revealing that the success of defense of resistant cucumber is due to rapidly mobilizing multiple responses. The unique responses detected were genes related to SA signaling, MAPK signaling, and Dof and WRKY transcription factors. Furthermore, 5 P. xanthii -inducible hub genes were identified, including GLPK, ILK1, EIN2, BCDHβ1, and RGGA, which are considered to be key candidate genes for disease control. This study combined multiple analytical approaches to capture potential molecular players and will provide key resources for developing cucumber cultivars resistant to pathogen stress.

Continuous monocropping can cause the buildup of autotoxins (e.g., phenolic compounds) in the soil, which can alter soil microbial community and inhibit plant growth. However, how different phenolic compounds affect certain soil microbiota is unclear. Here, we studied the response of cucumber rhizosphere Trichoderma spp. community to exogenously applied ferulic and p-coumaric acids by polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) and real-time PCR techniques. Results showed that ferulic acid, but not p-coumaric acid, increased the Trichoderma spp. abundance, and this increase were positively correlated with ferulic acid concentration. Moreover, ferulic acid changed the community structure, increased the number of DGGE bands, Shannon wiener, and evenness index values, while p-coumaric acid had no effect on all these parameters of Trichoderma spp. community. These results suggest that these two phenolic acids affected Trichoderma spp. differentially at the community level.

Abstract Background Fruit skin color play important role in commercial value of cucumber, which is mainly determined by the content and composition of chlorophyll and anthocyanins. Therefore, understanding the related genes and metabolomics involved in composition of fruit skin color is essential for cucumber quality and commodity value. Results The results showed that chlorophyll a, chlorophyll b and carotenoid content in fruit skin were higher in Lv (dark green skin) than Bai (light green skin) on fruit skin. Cytological observation showed more chloroplast existed in fruit skin cells of Lv. A total of 162 significantly different metabolites were found between the fruit skin of the two genotypes by metabolome analysis, including 40 flavones, 9 flavanones, 8 flavonols, 6 anthocyanins, and other compounds. Crucial anthocyanins and flavonols for fruit skin color, were detected significantly decreased in fruit skin of Bai compared with Lv. By RNA-seq assay, 4516 differentially expressed genes (DEGs) were identified between two cultivars. Further analyses suggested that low expression level of chlorophyll biosynthetic genes, such as chlM, por and NOL caused less chlorophylls or chloroplast in fruit skin of Bai. Meanwhile, a predicted regulatory network of anthocyanin biosynthesis was established to illustrate involving many DEGs, especially 4CL, CHS and UFGT. Conclusions This study uncovered significant differences between two cucumber genotypes with different fruit color using metabolome and RNA-seq analysis. We lay a foundation to understand molecular regulation mechanism on formation of cucumber skin color, by exploring valuable genes, which is helpful for cucumber breeding and improvement on fruit skin color.

Tonoplast sugar transporters (TSTs) play essential roles in regulating plant growth, development, and response to various biotic and abiotic stresses. In this study, a total of three TST genes were identified by a genome-wide analysis in cucumber. Phylogenetic analysis showed that TST proteins from cucumber and other plant species can be classified into five groups, and nearly all TST members in the same groups displayed similar motif distributions, transmembrane (TM) domains, and gene structures. All of the three CsTST genes possess a number of development-, stress-, and hormone-related cis-elements in the promoter sequences. Meanwhile, qRT-PCR assays revealed that the CsTST1 was expressed in fruits, flowers, leaves, and other tissues, and its expression varied significantly under various abiotic stresses such as cold, salt, drought (PEG), and abscisic acid (ABA). Finally, functional analysis of CsTST1 in yeast revealed that it was able to complement the deficiency in galactose, mannose and sucrose transport. These results revealed that CsTST1 can act as a functional sugar transporter to play important roles in cucumber growth and response to abiotic stress probably through affecting carbohydrate distribution.

The effect of exogenous methyl jasmonate (MJ) on cucumber plants (Cucumis sativus L.) exposed for 3 days to 4 °C was studied. It was shown that a temperature of 4 °C has a damaging effect on seedlings, causing a significant increase in electrolyte leakage and irreversible inhibition of growth processes. Along with this, an increase in lipid peroxidation was observed in the leaves of the seedlings, as indicated by the accumulation of malondialdehyde (MDA). MJ treatment (1 µM) of plants one day before the onset of cold exposure had a protective effect evidenced, in particular, by a decrease in the MDA levelin the leaves. In addition, the leakage of electrolytes from leaf tissues in this case was significantly lower throughout the entire period of exposure to cold, and leaf sizes in seedlings treated with MJ exceeded those in the variant with exposure to cold without MJ pretreatment. It is concluded that MJ can reduce the detrimental effect of low damaging temperature on plants, and the possible mechanisms of this protective effect are briefly discussed.

A daily short-term temperature drop in the end of the night or in the morning is commonly used in greenhouse production of transplants of a number of vegetable and bedding plants and ornamental plants for plant height control as an alternative to chemical growth retardants. The aim of this work was to quantify the effects of a temperature drop at different times of the day and night on growth, photosynthetic activity and chilling tolerance of cucumber (Cucumis sativus L.) and tomato (Solanum lycopersicum L.) plants. Plants were grown under air temperature of 23 °C, a photoperiod of 12 h under controlled environmental conditions in growth chambers with a photosynthetic photon flux density of 200 µmol m-2 s-1. Starting from the 7th (for cucumber) or 14th (for tomato) day from seed soaking, plants were on each of the following 6 days exposed to a temperature of 10 °C for 2 h at the beginning, in the middle and in the end of the night and at the beginning, in the middle and in the end of the day. The results show that temperature drop treatments retard the linear growth of the plants regardless of their timing in the daily cycle. The optimal time for temperature drop treatments in order to obtain compact plants may not coincide with the periods of the highest growth rate of the stem as a temperature drop itself is capable of modifying the course of plant growth in the daily cycle. Light conditions during the chilling treatment (light or darkness) rather than diurnal variation of plant sensitivity to chilling are responsible for plant response to temperature drop treatments. The resultant data confirm the presence of a well-pronounced species specificity in plant responses to a daily short-term temperature drop.

During anthesis, there is an increased demand for carbohydrates due to pollen maturation and nectary secretion that warrants a systematic phloem unloading strategy for sugar partitioning. Sugar transporters are key components of the apoplasmic phloem unloading strategy and control the sugar flux needed for plant development. Currently, the phloem unloading strategy during anthesis has not been explored in cucumber, and the question of which sugar transporters are active during flower anthesis is poorly understood. In this study, a study utilizing the phloem-mobile symplasmic tracer carboxyfluorescein (CF) suggested that the phloem unloading was symplasmically isolated in the receptacle and nectary of cucumber flowers at anthesis. We also identified a hexose transporter that is highly expressed in cucumber flower, Sugar Will Eventually be Exported Transporter 7a (SWEET7a). CsSWEET7a was mainly expressed in receptacle and nectary tissues in both male and female flowers, where its expression level increased rapidly right before anthesis. At anthesis, the CsSWEET7a protein was specifically localized to the phloem region of the receptacle and nectary, indicating that CsSWEET7a may function in the apoplasmic phloem unloading during flower anthesis. Although cucumber mainly transports raffinose family oligosaccharides (RFOs) in the phloem, sucrose, glucose, and fructose are the major sugars in the flower receptacle and the nectary as well as in nectar at anthesis. In addition, the transcript levels of genes encoding soluble sugar hydrolases (α-galactosidase, sucrose synthase, cytoplasmic invertase, and cell wall invertase) were correlated with that of CsSWEET7a. These results indicated that CsSWEET7a may be involved in sugar partitioning as an exporter in the phloem of the receptacle and nectary to supply carbohydrates for flower anthesis and nectar secretion in cucumber.

Salicylic acid (SA) is a phenolic compound capable of inducing physiological and metabolic changes that enhance the tolerance of plants to saline stress associated with using a hydroponic system and enable the use of saline water in semi-arid regions. In this context, this assay aimed to evaluate the impact of the foliar application of SA on mitigating salt stress effects on Japanese cucumber cultivated in a hydroponic system. The experiment was carried out in a protected ambient (greenhouse), using the Nutrient Film Technique—NFT hydroponic system. A completely randomized design was performed in a 4 × 4 split-plot scheme, with four levels of electrical conductivity of the nutrient solution—ECns (2.1, 3.6, 5.1, and 6.6 dS m−1)—considered as plots and four SA concentrations (0, 1.8, 3.6, and 5.4 mM), regarded as subplots, with four replicates and two plants per plot. An increase in the ECns negatively affected the physiology, production components, and post-harvest quality of cucumber. However, the application of SA to leaves at concentrations between 1.4 and 2.0 mM reduced the deleterious effects of saline stress and promoted an increase in the production of and improvement in the post-harvest quality of cucumber fruits.

Relevance. The development of F1 hybrids distinguishing it from cultivars by high productivity, plant uniformity in ripening date, fruit sizes and quality is the promising trend in breeding program in cucumber (Cucumis sativus L.).The aim of the study was to optimize the gynogenesis induction condition in culture of unpollinated ovules in vitro in order to broad the generation of new breeding forms and to accelerate homozygous line production.Materials and methods. Eight promising cucumber accessions from Laboratory of Cucurbit Breeding and Seed Production (FSBSI FSVC) were taken for the study. The protocol developed in Laboratory of Biotechnology (FSBSI FSVC) for production of doubled haploid in Cucurbitaceae family was used in the experiment. The medium IMC with 30 g/L sucrose and 7g/L agar supplemented with 200 mg/L ampicillin and 0.2 mg/L thidiazuron (TDZ) was applied to induce gynogenic development.Results. The half-open bud or flower was shown to be the most suitable to be taken as an explant for cultivation. Highest number of embryo-like structures in all accessions developed from ovaries 2.1-2.6 cm long. Exposure to sterilization solution of sodium hypochlorite for 15 min made ovary wall softer and ovules can be then easily extracted without traumatizing. The traumatized ovule resulted in inhibited gynogenic development. Embryoids and calli had developed in all studied cucumber accessions, but well-formed plants were only obtained in six accessions. In total 26 plants were produced. The maximum gynogenesis induction equal to 63.1% was achieved in accession 1810. Maximum number of plant produced was twelve in accession 1763, but the greatest plant outcome 7.7% of the ovules with induced gynogenesis was observed in accession 1807.

The downy mildew disease of cucurbits is considered the most economically damaging disease of Cucurbitaceae worldwide. The causal agent, Pseudoperonospora cubensis (Berkeley & Curtis), may cause complete crop losses of cucurbits. Few commercial cucurbit cultivars are resistant to this disease. Commercially, P. cubensis is controlled primarily with synthetic fungicides that inhibit or eliminate the pathogen. Several biological agents have also been identified that provide some level of control. In our study, foliar applications of three strains of Trichoderma harzianum and two native strains of Bacillus subtilis were evaluated for the control of the disease on cucumber plants grown under commercial greenhouse conditions. The study was conducted using a completely randomized design with six individual treatments during two production cycles: fall 2015 and spring 2016. The response variables included disease incidence and severity, plant height, total yield, fruit quality, and weight. B. subtilis provided the best control over the incidence and severity of the disease in both production cycles. Interestingly, while T. harzianum was less effective at controlling the disease, it enhanced plant growth and productivity, and produced a higher number of better-quality fruits per plot. This increased yield with higher quality fruits may result in higher profit for the growers.

This 8-week randomized double-blind placebo-controlled study aimed to assess the effectiveness of supplementation with an extract of Cucumis sativus L. (20 mg/day) on pain and other variables in patients with knee osteoarthritis (OA) over 40 years. The change in pain intensity using a 1–10 cm visual analog scale (VAS) was the primary endpoint. Fifty-five patients (mean age 50.6 ± 8.6 years) were included (experimental group, n = 29; placebo, n = 26). VAS scores for pain decreased significantly in both study groups, but decreases were higher in the experimental group (between-group p = 0.013). Improvements in pain, stiffness, and physical function according to the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were also significantly higher in the experimental group. The Timed Up and Go test result also decreased significantly in the experimental group. An improvement in muscle function was associated with significant increases in isokinetic and isometric dynamometry variables, particularly for isometric 60°·s−1 and 180°·s−1 knee flexion exercises in the experimental group. Plasma levels of interleukin-1-beta (IL-1β) and matrix metalloproteinase-3 (MMP-3) also decreased significantly in the experimental group. Based on the beneficial effects of cucumber on symptomatology and inflammatory and cartilage degradation biomarkers in knee OA, cucumber extract supplementation may a useful natural approach to maintain healthy joints.

Mediterranean greenhouses are usually covered by plastic materials (films); these films allow light to pass through them, modifying some of their characteristics. The properties of the plastic cover influence the development of greenhouse crops. In addition, it can influence the stresses that the plants endure and the development of fungal diseases in the crop. The aim of this study is to analyze the effect that an experimental film cover, with high transmittance and high light diffusivity, produces on the development of fungal diseases on a cucumber crop (Cucumis sativus L.). Two different film covers were compared: (i) commercial film (transmittance of 85%; diffusivity of 60%); and (ii) experimental film (transmittance of 90%; diffusivity of 55%). The study was carried out across two autumn–winter crop cycles in a multi-span greenhouse divided into two isolated sectors. Three fungal diseases caused the main damage to the cucumber crop: downy mildew (Pseudoperonospora cubensis), powdery mildew (Sphaerotheca fuliginia) and gummy stem blight (Didymella bryoniae). In the case of powdery mildew, a greater severity in the sector was observed with the commercial film in comparison with the sector with the experimental film, with significant statistical differences between the two sectors in both crop cycles. Downy mildew and gummy stem blight were fungal diseases with less presence than downy mildew, and a greater presence of these two fungal diseases in the sector with the commercial film was also observed in both crop cycles.

Using proper greenhouse covering materials can provide a suitable environment for plant growth in Saudi Arabia. The effects of three different greenhouse covering materials, clear glass, polycarbonate and diffuse tempered glass were used to evaluate its effect on cucumber productivity, water and energy use efficiency. Results show that either water or light use efficiency was higher in compartments covered with diffused or clear glass than polycarbonate compartment. Inconsequence, fruit yield of cucumber plants/m2 was significantly higher (58%) in clear and diffuse glass greenhouses as opposed to polycarbonate greenhouse. In term of the effect of cultivar or plant density, no significant differences on cucumber yield were found. Using of different covering materials did affect environmental data of greenhouses. Less light was transmitted through polycarbonate cover than clear or diffuse glass. The photosynthesis active radiation (P.A.R.) was 996, 1703, 1690 mol/m2/d, while the electricity consumption was 2.97, 3.44, and 2.88 kWh under polycarbonate, clear glass, and diffuse glass, respectively. Meanwhile, diffuse glass compartment revealed 16% lower of water consumption than other covering materials. In this respect, it could be concluded that using diffuse glass, as a greenhouse cover material, has a strong positive influence on crop productivity under Saudi Arabia climate.

Implementation of cell technologies has essentially improved the plant breeding process in agricultural crops in the world. The production of pure lines in cultivated crops, particularly among cross-pollinated species such as cucumber (Cucumis sativus L.) requires much time, labor and expense. Thus, the use of DH-plants for production of fully homozygous lines for one year becomes a very promising method for near cucumber breeding program. The major factor limiting the wide use of DH is a lack of effective protocol for large-scale plant production. In this review the historical facts with description of three main methods of DH-plant production were presented. By now these three methods have been such as parthenogenesis in situ induced by pollination with irradiated or chemically treated pollen; androgenesis in vitro including anther and isolated microspore cultivation in vitro; gynogenesis through ovule cultivation in vitro. Comparative analysis of published data with regard to the efficiency of the technology for DH-plant production was shown as well as advantages and limitations of each technology were described.

Relevance Traditional breeding methods are based on crossing and selection of genotypes among hybrid offspring. In recent decades, along with traditional methods, more and more attention is paid to alternative methods of selection, based on biotechnological manipulations with plants. One of the most important methods of biotechnology is the method of cell selection, which is based on the replacement of the whole plant, as a unit of selection, on its cell. Applying biotechnology techniques from a single plant can produce millions of cells, which increases the chances of finding, eliminating the need for areas for the cultivation of tested plants. As well as accelerating the selection process due to the possibility to carry out the study in the offseason. Methods The studies used the linear material of C. sativus hybrids of All-Russian Scientific Research Institute of Vegetable Growing – Branch of the FSBSI Federal Scientific Vegetable Center and Agroholding "Poisk". Plants were cultivated in laboratory room conditions. As explants used hypocotyl 0.5-1 cm segments isolated from young plants. Results To obtain Cucumis sativus plants with increased resistance to Fusarium by cell selection method, it is recommended to alternate culturing of callus on a non – selective medium containing sucrose in a concentration of 30 g/l, agar – 7 g/l, 0.1 mg/l, NUC – 0.5 mg/l and the filter of the cultural fluid of the fungus in a concentration of 10% within 3 passages.

This study was conducted to identify ideal irrigation and fertigation levels for maximum yields and profitability of cucumber grown in a substrate-bag cultivation system. The experiment was laid out in randomized complete-block design, with combinations of four drip irrigation rates (75, 100, 125, or 150% of crop evapotranspiration (ETc)) and three fertilization (F) levels (60, 100, or 125% of one dose of Yamazaki nutrient solution formula). The 'irrigation level × fertilization level' interaction significantly affected cucumber yield and nitrogen accumulation. The treatment combination of 125% ETc and 100% F promoted yield relatively best. Plants were grown in the 125% ETc and 125% F treatment combination accumulated the most nitrogen. The greatest nitrogen use efficiency (NUE) was observed in the 100% ETc plus 60% F treatment combination. Water use efficiency (WUE) decreased with increasing irrigation rate, and considering just one fertilization level. Through the multivariate regression analysis and the spatial analysis methods to evaluate yield, WUE, and NUE, we conclude that the combination of 13.54-23.78 g/plantand 37.71-52.59 L/plant were the best strategy of fertigation and irrigation for the production of drip-irrigated cultivated cucumber grown in substrate bags in spring.

Arbuscular mycorrhiza (AM) is known to enhance the rate of photosynthesis in plants, but there is little information on whether this effect is maintained at low temperature when the development of AM fungi is restrained. We therefore investigated the influence of AM on gas exchange, PSII fluorescence, and some photosynthesis-related biochemical parameters in cucumber seedlings under cold stress. Cold stress decreased, as expected, the chlorophyll content, net photosynthetic rate, and parameters related to photochemical quenching, while increasing nonphotochemical quenching and sugar contents in leaves. In contrast, AM had opposite effects on most of the determined parameters; it improved the efficiency of photosynthesis in the cucumber seedlings both at cold stress and at control ambient temperature. In addition, we recorded significant alleviation of the cold stress effect on sugar contents in leaves, which indicated that higher carbon-sink strength was an important factor maintaining higher efficiency of photosynthesis in mycorrhizal cucumber seedlings under cold stress.

Studying of plant growth stimulants is an important task for scientists. Triacontanol Н3С(СН2)28СН2ОН is a fatty alcohol, also known as melicylic alcohol or myricyl alcohol found in cuticular waxes of plants, and is a part of beeswax. Triacontanol was first discovered as a component of alfalfa cuticular wax Medicago sativa L. Study of the biological activity of this alcohol began in the last century and continues in different countries. Industrial produced triacontinol sample obtained from the beeswax contains impurities of other fatty alcohols that can neutralize the effect of the triacontanol. Study of the industrial produced triacontanol sample from Huzhou Sifeng Biochem Co.Ltd, China on growth and content of nitrates in sunflower and cucumber seedlings was conducted. In the industrial produced triakontanol used in our experiments, the composition of alcohols was as follows: triacontanol 95.6%, dotirancontanol 1.9 %, octacosanol 1.3 %, nonaccosanol 0.38 %, and the rest (less than 0.5 %) belong to heptacosanol and hexacosanol. Our studies have shown that the preparation at a concentration of 1 mg/L increases morphometric indices of sunflower seedlings and cucumbers, while the concentration of 25 mg/L reduces them, and the concentration of 10 mg/L is almost unaffected. With an increase of triacontanol concentration the content of nitrates decreased in both types of seedlings (however, within the statistical error), which may be explained by an increase in the intensity of the use of nitrates. Concomitant alcohols available in the industrial produced triacontanol sample, practically haven’t any effect. In our opi­nion, triacontanol can be applied in crop production to increase plant growth. Concentra­tion of 1 mg/L is the most effective, and therefore, available for use in agriculture, as well as for cultivation the of medicinal plants. Consequently, the use of triacontanol is an effective way to increase the size of plant seedlings, that may result in an increase in the yield of these plants.

A severe disease with leaf spots and necrotic symptoms was observed in cucumber (Cucumis sativus L.) seedlings in April 2018 at a nursery in Kimjae, Korea (35°47'09.8"N 127°2'24.3"E). The infected plants initially showed spots on water-soaked cotyledons which, at later stages, enlarged and spread to the leaves, which the lesions becoming dry and chlorotic. The symptomatic samples were collected from cucumber and the isolates were cultured on LB agar. The representative bacterial strain selected for identification showed fluorescent on King’s medium B, was potato rot-positive, levan and arginine dihydrolase-negative, oxidase-negative and tobacco hypersensitivity-positive in LOPAT group 2 as determined by LOPAT tests. A pathogenicity test was carried out on a 3-week-old cucumber. After 3 days of inoculation, leaf spots and necrotic symptoms appeared on the cucumber, similar to the originally infected plants. The infecting bacterial strain was identified as Pseudomonas viridiflava, by 16S rDNA sequence analysis. This is the first report of leaf spot diseases on cucumber caused by P. viridiflava.

Numerous factors lead to the use of water with saline levels above those suitable for plant development, resulting in negative consequences on crops. Studies have sought techniques that aim to mitigate such consequences and the use of vitamins is promising, since these compounds improve the conditions of vegetables. Thus, the study aimed to verify the ability of vitamins to mitigate the deleterious effects of using saline water, applied via irrigation during the formation of cucumber seedlings. Cucumber seeds were subjected to imbibition in three vitamin solutions (100 mg L-1 thiamine; 100 mg L-1 niacin; 50 mg L-1 thiamine + 50 mg L-1 niacin), in addition to two controls, both with water imbibition . After sowing, irrigation was carried out with saline water (100 mM NaCl), for all treatments, except for one of the controls. It was found that irrigation with saline water affected all variables studied, without, however, having a positive effect from the application of vitamins. Thus, it was concluded that the vitamins were not able to mitigate the deleterious effects caused by the application of saline water under the conditions in which the study was carried out and that future studies should be carried out to evaluate different concentrations and forms of application of the vitamins.

Leaf color mutants are the ideal materials to explore the pathways of chlorophyll metabolism, chloroplast development and photosynthesis system. In this study, a new virescent leaf mutant 104Y was identified by spontaneous mutation, whose cotyledon and upper five true leaves were yellow color. The yellow true leaves gradually turned green from top to bottom with increased chlorophyll contents. Genetic analysis indicated that the virescent leaf was controlled by one single recessive gene v-2, which was accurately mapped into 36.0–39.7 Mb interval on chromosome 3 by using BSA-seq and linkage analysis. Fine mapping analysis further narrowed v-2 into 73-kb genomic region including eight genes with BC1 and F2 populations. Through BSA-seq and cDNA sequencing analysis, only one nonsynonymous mutation existed in the Csa3G890020 gene encoding auxin F-box protein was identified, which was predicted as the candidate gene controlling virescent leaf. Comparative transcriptome analysis and quantitative real-time PCR analysis revealed that the expression level of Csa3G890020 was not changed between EC1 and 104Y. However, RNA-seq analysis identified that the key genes involved in chlorophyll biosynthesis and auxin signaling transduction network were mainly down-regulated in 104Y compared with EC1, which indicated that the regulatory functions of Csa3G890020 could be performed at post-transcriptional level rather than transcriptional level. This is the first report to map-based clone an auxin F-box protein gene related to virescent leaf in cucumber. The results will exhibit a new insight into the chlorophyll biosynthesis regulated by auxin signaling transduction network.

In a previous study, we found that H2S alleviates salinity stress in cucumber by maintaining the Na+/K+ balance and by regulating H2S metabolism and the oxidative stress response. However, little is known about the molecular mechanisms behind H2S-regulated salt-stress tolerance in cucumber. Here, an integrated transcriptomic and proteomic analysis based on RNA-seq and 2-DE was used to investigate the global mechanism underlying H2S-regulated salt-stress tolerance. In total, 11,761 differentially expressed genes (DEGs) and 61 differentially expressed proteins (DEPs) were identified. Analysis of the pathways associated with the DEGs showed that salt stress enriched expression of genes in primary and energy metabolism, such as photosynthesis, carbon metabolism and biosynthesis of amino acids. Application of H2S significantly decreased these DEGs but enriched DEGs related to plant-pathogen interaction, sulfur-containing metabolism, cell defense, and signal transduction pathways. Notably, changes related to sulfur-containing metabolism and cell defense were also observed through proteome analysis, such as Cysteine synthase 1, Glutathione S-transferase U25-like, Protein disulfide-isomerase, and Peroxidase 2. We present the first global analysis of the mechanism underlying H2S regulation of salt-stress tolerance in cucumber through tracking changes in the expression of specific proteins and genes.

ABSTRACT: Enhancing the plant rhizosphere microbial community function by increasing plant diversity in the field is a promising strategy for enhancing agricultural sustainability. This study evaluated the effectiveness of the intercropping of wheat in controlling cucumber Fusarium wilt disease. Bacterial community diversity and abundance in cucumber rhizosphere were estimated by high-throughput amplicon sequencing and quantitative polymerase chain reaction (PCR). Results showed that the intercropping of wheat inhibited the severity of cucumber seedling Fusarium wilt disease, increased the alpha diversity and altered the composition of the bacterial community in cucumber rhizosphere. Compared with monocropped cucumber, intercropped cucumber had higher relative abundances of Anaerolineae, Deltaproteobacteria, Phycisphaerae and Planctomycetacia, and lower Alphaproteobacteria and Cyanobacteria. Moreover, the intercropping of wheat promoted bacterial genera with plant-beneficial potential (e.g. Pseudomonas, Haliangium and Archangium spp.) in cucumber rhizosphere. Quantitative PCR confirmed that Pseudomonas spp. abundance was higher in intercropped cucumber rhizosphere than in monocropped cucumber rhizosphere. Overall, the intercropping of wheat decreased the severity of Fusarium wilt of cucumber and promoted potential plant-beneficial microbes in cucumber rhizosphere.

Abstract Background It is widely accepted the key role of endothelium in the onset of many chronic and acute vascular and cardiovascular diseases. In the last decade, traditional compounds utilized in “folk medicine” were considered with increasing interest to discover new bioactive molecules potentially effective in a wide range of diseases including cardiovascular ones. Since ancient times different parts of the Cucumis sativus L. plant were utilized in Ayurvedic medicine, among these, fruits were traditionally used to alleviate skin problem such as sunburn irritation and inflammation. The main purpose of the present research was, in a well-defined in vitro model of endothelial cells, to investigate whether a water/ethanol extract of Cucumis sativus L. (CSE) fruit can attenuate the damaging effect of pro-inflammatory lipopolysaccharide (LPS). Methods Cell viability, gene expression of endothelial cell markers, cytokines secretion and in vitro angiogenesis assay were performed on porcine Aortic Endothelial Cells exposed to increasing doses (0.02; 02; 2 mg/ml) of CSE in the presence of pro-inflammatory lipopolysaccharide (LPS 10 μg/ml). Results CSE reduced LPS-induced cytotoxicity and decreased the cellular detachment, restoring the expression of tight junction ZO-1. The increase of TLR4 expression induced by LPS was counterbalanced by the presence of CSE, while the protective gene Hemeoxygenase (HO)-1 was increased. Cucumis sativus L. inhibited the early robust secretion of inflammatory IL-8 and GM-CSFs, furthermore inhibition of inflammatory IL-6 and IL-1α occurred late at 7 and 24 h respectively. On the contrary, the secretion of anti-inflammatory IL-10, together with IL-18 and IFN-γ was increased. Moreover, the in vitro angiogenesis induced by inflammatory LPS was prevented by the presence of Cucunis sativus L. extract, at any doses tested. Conclusions Our results have clearly demonstrated that Cucumis sativus L. extract has attenuated lipopolysaccharide-induced inflammatory response in endothelial cells.

Мета. Визначити кращі партенокарпічні гібриди корнішонного типу за рівнем прояву господарсько-цінних ознак в умовах захищеного грунту весняно-літньої культурозміни. Методи. Протягом 2015–2017 рр. в умовах захищеного ґрунту плівкових теплиць проведено комплексне оцінювання 18 генотипів огірка селекції Інституту овочівництва та баштанництва НААН України, отриманих шляхом штучної гібридизації селекційного матеріалу в попередні роки. Стандартом слугував вітчизняний гібрид ‘Надія F1’. Результати. За результатами оцінювання за комплексом господарсько-цінних ознак серед перспективних генотипів було відібрано сім гібридів F1. Виділені зразки партенокарпічного типу (58,7–79,5%), скоростиглі (від масових сходів до початку плодоношення – 51–53 доби) з жіночим типом цвітіння (80–100%) та букетним розташуванням жіночих квіток (по 3–5). Період плодоношення – 40–45 діб. Загальна врожайність цих гібридів становить від 16,2 до 21,2 кг/м2 (перевищення стандарту на 5–37%) з товарністю плодів 82–90%. Середня маса товарного плоду – 91–100 г (стандарт – 88 г). Гібриди F1 стійкі проти кореневих гнилей та відносно стійкі проти несправжньої борошнистої роси. Дегустаційна оцінка свіжих плодів – 4,6–4,9 бала, консервованих – 4,4–4,5 бала. За даними дослідження рівня гетерозису генотипів за ознакою ‘партенокарпія’ чотири гібриди виявили позитивне наддомінування. За ознакою ‘врожайність’ три гібриди мали позитивне наддомінування з ефектом гетерозису 126–142%. За ознакою ‘скоростиглість’ п’ять гібридів виявили негативне домінування та наддомінування. Позитивне домінування та наддомінування з ефектом гетерозису 101–113% отримано в п’яти гібридів за ознакою ‘товарність’. Висновки. У результаті селекційної роботи створено нові конкурентноздатні партенокарпічні генотипи огірка корнішонного типу для вирощування в захищеному грунті плівкових теплиць весняно-літньої культурозміни. Нові гібриди огірка ще пройдуть перевірку в попередньому та конкурсному сортовипробуванні, за результатами яких кращі з них будуть передані на кваліфікаційну експертизу.

The objectives of this study were to evaluate the yield of different types of cucumbers from the perspective of yield components. The yield and yield components of nine cucumber cultivars (Beit Alpha, Greenhouse, and Japanese) grown hydroponically in a greenhouse were investigated. Fruit yield fresh weight in the Beit Alpha type was higher than that of the Japanese type, and the fruit yield fresh weight was significantly correlated with fruit yield dry weight, total dry matter (TDM), fraction of fruits, and number of fruits. However, the fruit yield fresh weight was not significantly correlated with intercepted light, light use efficiency (LUE), leaf area index, light extinction coefficient, and fruit dry matter content. High fruit yield dry weight was associated with a high TDM and the fraction of fruits. Moreover, the high TDM and fraction of fruits were associated with LUE and the number of fruits, respectively.

Two genes, CsLRR-RPK2 (CsGy5G015660) and CsaMLO8 (Csa5G623470), have been considered as powdery mildew (PM) resistance genes in cucumbers. In this study, we evaluated the involvement of the alleles of these two genes in PM resistance in 100 commercial Korean cucumber inbred lines. To achieve this, we developed cleaved amplified polymorphic sequences (CAPS) and InDel markers from CsLRR-RPK2 and CsaMLO8. Genotyping analysis indicated that the CsLRR-RPK2-CAPS marker showed a stronger correlation with the PM-resistant phenotype, with an 84% consistency compared to the CsaMLO8-InDel marker. The use of the CsaMLO8-InDel marker showed a 70% consistency between phenotype and genotype results. It was proposed that the CsLRR-RPK2-CAPS marker successfully eliminated PM-susceptible inbred lines, since both genotype and phenotype results were 100% identical. Furthermore, the present study revealed that the introduction of one of these alleles is probably enough to confer PM resistance in cucumbers. However, seven PM-resistant inbred lines harbored either CsaMLO8 or CsLRR-RPK2 alleles, indicating that there is another PM-resistant resource(s) besides CsaMLO8- and CsLRR-RPK2–originated resistance in the commercial Korean inbred lines. Our results provide reliable evidence confirming two PM-resistant candidate genes for the detection of PM resistance resources in cucumber inbred lines.

Protected vegetable cultivation is a fast-growing sector in which grafting plays a crucial role for success. Cucumber is predominantly grown under protected conditions. The popular slicing (mini) cucumber comprises two segments, single- and cluster-fruit-bearing. In the present study, the performance of select fruit-bearing hybrids grafted as scions onto commercial Cucurbita hybrid rootstock ‘NS-55’ was evaluated under three different low-cost protected structures in arid regions. With respect to type of protected structure, cucumber performance was superior under a naturally ventilated polyhouse (NVP) than an insect net house (INH) or a shade net house (SNH). Micro-climate parameters inside NVP (air temperature, RH and PAR) were more congenial for cucumber than those in net houses, thereby facilitating improved physiology (chlorophyll fluorescence, chlorophyll and plant water potential) and leaf mineral status. Grafting invariably improved growth and yield parameters under all protected structures. Overall plant performance was better in the grafted cluster-fruit-bearing hybrid ‘Terminator’ than the single-fruit-bearing hybrid ‘Nefer’ or their non-grafted counterparts. Furthermore, NVP was found to be superior to net houses for water productivity, and grafted plants were more water use efficient than their counterpart non-grafted plants. Thus, NVP can be considered a suitable low-cost protected structure in conjunction with grafting to boost cucumber crop and water productivity in arid regions.

The objective of this study was to evaluate peat and zeolite mixtures substrates performance on cucumber seedling quality and crop yield. The research was carried out in a greenhouse covered with double polymeric film at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry. Cucumber seedlings were grown in different substrates: peat, peat + zeolite 1 : 1, peat + zeolite 2 : 1, peat + zeolite 3 : 1 and peat + zeolite 4 : 1. Cucumber seedlings grown in peat and zeolite substrates are shorter; the leaf area is smaller than that of the seedlings grown in peat alone. The dry mass of the aboveground part of these seedlings is lower (difference insignificant), however, the root mass is higher than those grown in peat alone. The addition of zeolite to peat substrate does not have any positive effect on the photosynthesis pigment content in cucumber seedling leaves. The physiological growth indices of the seedlings grown in peat-zeolite substrates were lower compared to those grown in peat. When zeolite is added to peat substrate, net assimilation rate is higher compared to those grown in peat. Higher yields (significant difference) were demonstrated by cucumbers, the seedlings of which had been grown in peat-zeolite substrates.

For its specific physical and physicochemical properties, the water treated with low-frequency low-pressure glow plasma (GPTW) affects the growth of plants and enhances the phytoavalibility of selenium (Se) ions from the nutrient solution. The basic biometric and physiological parameters of cucumber and the uptake of Se ions applied as selenate (Na2SeO4) from the nutrient solution prepared using GPTW or distilled water (DW) were compared. In the presence of Se, the fresh weight (f.w.) of shoots of plants growing in water-differentiated nutrient solutions did not differ, whilst their dry weight (d.w.) and leaf area (LA) were higher in plants grown in the GPTW- than in DW-containing medium. The use of GPTW for preparation of the nutrient solution was associated with a substantial improvement of Se ions phytoavailability, compared to the regular growth medium based on DW. Despite the higher Se bioaccumulation in the GPTW- than in DW-based medium, the phytotoxicity of this element was not enhanced. GPTW-induced Se accumulation was remarkable and hence recommended for further study to understand the detailed mechanism GPTW action.

ABSTRACT: Persistence of an herbicide is defined as the ability to maintain the integrity of its molecule and chemical, physical, and phytotoxic properties in the environment where it was applied. Knowledge of persistence has implications both for the toxicity generated on species grown in succession and for the period in which the herbicide controls weeds. This study aimed to assess the persistence of the herbicide saflufenacil in an Oxisol by means of bioassays. Two experiments with the application of 29.4 g ha-1 of saflufenacil were carried out under field conditions: the first in the 2011/2012 season and the second in the 2012/2013 season. Soil samples were collected at depths of up to 10 cm at different times after application. Subsequently, two bioassays were carried out in a greenhouse by using beet (Beta vulgaris L.) and cucumber (Cucumis sativus L.) as bioindicators. The studies were carried out in a completely randomized design with four replications. Treatments consisted of periods after saflufenacil application (0, 5, 10, 15, 25, 35, 50, and 100 days). The crop was also considered as a factor. Stand, height, and phytotoxicity of plants were assessed in both agricultural seasons at 14, 21, and 28 days after sowing (DAS), as well as shoot fresh (SFM) and dry matter (SDM) at 28 DAS. In general, saflufenacil persistence was between 25 and 35 days. Beet was more sensitive to the presence of saflufenacil in the soil when compared to cucumber. Herbicide effects were higher in the 2012/2013 season when compared to the 2011/2012 season.

Salinity stress from soil or irrigation water can significantly limit the growth and development of plants. Emerging evidence suggests that hydrogen sulfide (H2S), as a versatile signal molecule, can ameliorate salt stress-induced adverse effects. However, the possible physiological mechanism underlying H2S-alleviated salt stress in cucumber remains unclear. Here, a pot experiment was conducted with an aim to examine the possible mechanism of H2S in enhancement of cucumber salt stress tolerance. The results showed that H2S ameliorated salt-induced growth inhibition and alleviated the reduction in photosynthetic attributes, chlorophyll fluorescence and stomatal parameters. Meanwhile H2S increased the endogenous H2S level concomitant with increased activities of D/L-cysteine desulfhydrase and β-cyanoalanine synthase and decreased activities of O-acetyl-L-serine(thiol)lyase under excess NaCl. Notably, H2S maintained Na+ and K+ homeostasis via regulation of the expression of PM H+-ATPase, SOS1 and SKOR at the transcriptional level under excess NaCl. Moreover, H2S alleviated salt-induced oxidative stress as indicated by lowered lipid peroxidation and reactive oxygen species accumulation through an enhanced antioxidant system. Altogether, these results demonstrated that application of H2S could protect cucumber seedlings against salinity stress, likely by keeping the Na+/K+ balance, controlling the endogenous H2S level by regulating the H2S synthetic and decomposition enzymes, and preventing oxidative stress by enhancing the antioxidant system under salinity stress.

Se sembraron tres genotipos comerciales de pepino (Cucumis sativus L.), Modan RZ, Tropicuke y Monalisa, en ambiente protegido con sistema hidropónico abierto en San Carlos, Costa Rica. Las plantas se trasplantaron en contenedores plásticos con sustrato de fibra de coco provisto de un sistema de fertirriego y tutorado, se realizaron mediciones de crecimiento, producción, y absorción de nutrientes. Los niveles de absorción de nutrientes, crecimiento y producción fueron diferentes entre genotipos. El orden de absorción de macronutrientes en todos los cultivares fue K>N>Ca>Mg>P, y de micronutrientes fue Fe>Zn>Mn>Cu. Los rangos de crecimiento de los genotipos fueron de 270.03 a 287.92 y 221.72 a 278.28 cm de altura máxima, 61.86 a 82.83 y 18.27 a 20.75 hojas por planta, 432.98 a 562.83 y 148.88 a 202.47 cm2 en área foliar, 6.41 a 8.34 y 2.21 a 4.16 de índice de área foliar, 294.86 a 349.70 y 174.94 a 206.50 g de peso fresco vegetativo (parte aérea + raíz), 342.60 a 361.97 y 203.67 a 274.40 g de peso fresco de fruto, 21.38 a 27.76 y 13.55 a 15.38 g de peso seco vegetativo, 5.53 a 11.06 y 4.43 a 7.92 g de peso seco de fruto respectivamente. El rendimiento en el cv Modán RZ fue superior con un total de 2895.31 g/planta, y el menor fue de 2001 g/planta.