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AbstractPeat and perlite are considered traditional growing substrates in soilless culture. The high cost of both and the urgent need for agricultural waste recycling prompted scientists and soilless culture growers to find alternative growing substrates provide optimal growth conditions and help dispose waste safely. In this study, corn cobs (CB) were tested as growing media and compared with peat moss (PM) and perlite (P). The organic wastes tested: CB, PM, and P were examined with washed sand (WS) at five treatments (WS, CB, CB + peat, CB + P and CB + sand). Cucumber (Cucumis sativus L.) plants were cultivated using 5 kg pots that contained the investigated substrates. Vegetative growth parameters, early fruiting stage, photosynthetic pigments, and cucumber yield had the highest values with CB and CB + P substrates, while the lowest ones were found in WS and CB + WS. CB resulted in greater flowering with the number of fruits per plant and yield being 39.70%, 37.33%, and 33.67%, 29.88 in both seasons, higher than the lowest substrate (WS). Although adding P to CB showed the highest values of measured growth characteristics, its high cost decreased net profit. Furthermore, CB characteristics as a growing media qualify it for use in cucumber soilless culture production. The use of this replacement media, which contains crushed CB, could reduce (but not eliminate) the need for PM and P in soilless culture. Also, using pyrolyzed biomass in growing media provides another way to convert biomass residues into valuable products. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Cucumber is an important member of Cucurbitaceae family which is grown and consumed globally. It is consumed in the form of salads or pickles and has abundant supply of minerals and vitamins. It has been a focus of extensive research due to its publically available genome sequences. Marker assisted breeding has been employed to generate improved varieties of cucumber with resistance to various diseases besides desirable horticultural traits. One such trait is the production of parthenocarpic fruits i.e. seedless fruits developed in the absence of pollination. Naturally, parthenocarpy occurs under unfavourable environmental conditions. However, it is possible to artificially induce parthenocarpy by applying plant growth regulators. At molecular level, parthenocarpy is a result of complex role-play of genes and hormones with tight regulation. Many researchers aim at developing parthenocarpic varieties by either transferring the trait into existing varieties with resistance to specific diseases or by knocking off genes controlling parthenocarpy. A comprehensive knowledge of background and genetics of parthenocarpy is required in both cases. This review includes an-inclusive study of the molecular basis of parthenocarpy. The genes and hormones involved and their functions, inheritance of parthenocarpy and markers associated with it have been given in detail. [ABSTRACT FROM AUTHOR]

SUMMARY: The target of rapamycin (TOR) kinase serves as a central regulator that integrates nutrient and energy signals to orchestrate cellular and organismal physiology in both animals and plants. Despite significant advancements having been made in understanding the molecular and cellular functions of plant TOR kinases, the upstream regulators that modulate TOR activity are not yet fully elucidated. In animals, the translationally controlled tumor protein (TCTP) is recognized as a key player in TOR signaling. This study reveals that two TCTP isoforms from Cucumis sativus, when introduced into Arabidopsis, are instrumental in balancing growth and defense mechanisms against the fungal pathogen Golovinomyces cichoracearum. We hypothesize that plant TCTPs act as upstream regulators of TOR in response to powdery mildew caused by Podosphaera xanthii in Cucumis. Our research further uncovers a stable interaction between CsTCTP and a small GTPase, CsRab11A. Transient transformation assays indicate that CsRab11A is involved in the defense against P. xanthii and promotes the activation of TOR signaling through CsTCTP. Moreover, our findings demonstrate that the critical role of TOR in plant disease resistance is contingent upon its regulated activity; pretreatment with a TOR inhibitor (AZD‐8055) enhances cucumber plant resistance to P. xanthii, while pretreatment with a TOR activator (MHY‐1485) increases susceptibility. These results suggest a sophisticated adaptive response mechanism in which upstream regulators, CsTCTP and CsRab11A, coordinate to modulate TOR function in response to P. xanthii, highlighting a novel aspect of plant–pathogen interactions. Significance Statement: Target of rapamycin (TOR) signaling pathway serves as a central integrator of diverse nutrient, energy, hormone, and environmental signals, playing a pivotal role in the precise regulation of cellular and organismal physiology. In this study, we reveal a novel mechanism involving the TCTP‐Rab11A module, which significantly contributes to plant stress responses by positively regulating the TOR signaling pathway. This discovery not only enhances our understanding of the complex regulatory networks in plants but also provides potential targets for improving plant resistance to biotic and abiotic stresses. [ABSTRACT FROM AUTHOR]

【Objective】In order to provide favorable genes for the analysis of the grafting healing mechanism of Cucumis sativus L. or Cucurbita moschata Duch. grafted seedlings and the molecular breeding of resistance of the cucumber and pumpkin vegetables, we conducted the analysis of the expression patterns of Bcl-2 associated athanogene（BAG）family proteins in the cucumber and pumpkin in response to abiotic stress and in response to light during cucumber or pumpkin grafting healing.【Method】Based on the genome information of the cucumber and pumpkin, the BAG gene family in the cucumber and pumpkin was identified through bioinformatics methods, and its physicochemical characteristics, chromosome mapping, gene structure, phylogeny and collinearity were analyzed. The expression patterns of BAG family proteins in the cucumber and pumpkin in response to abiotic stress and in response to light during cucumber or pumpkin grafting healing were analyzed. These data were based on the public database and the transcriptome sequencing data of the cucumber or pumpkin grafted seedlings in the process of grafting and healing.【Result】A total of 12 and 18 members of the BAG family were identified in the cucumber and pumpkin, respectively and they were all divided into two subfamilies and the gene members were highly conserved. The BAG of subfamily I was mainly involved in gene regulation and stress response, while the BAG of subfamily II was mainly involved in plant development. The BAG genes of cucumber and pumpkin had multiple linear relationships with Arabidopsis, Oryza sativa L. and Solanum lycopersicum L., respectively, but the CsaV3_1G017210 was relatively conservative and there was no collinearity with the BAG genes in Arabidopsis, rice, tomato and pumpkin. Different BAG genes possessed tissue-specific expression patterns. CsaV3_6G000970 and CmoCh08G008520 belonged to the BAG family molecular chaperone regulator 6. In both cucumber and pumpkin, they were upregulated during the grafting healing process and in response to abiotic stress.【Conclusion】BAG family genes respond differently to abiotic stress and light during the grafting healing process of the cucumber or pumpkin. These genes synergistically regulate the growth, development and grafting healing of the cucumber and pumpkin. BAGs play an important role in the process of the cucumber and pumpkin abiotic stress and cucumber or pumpkin grafting healing. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Haploidization technique is the modern and advanced breeding technique used to enhance economically essential crops, including cucumber, to meet consumers' preferences and needs worldwide. This study aimed to evaluate the effects of factors such as genotype, thermal pre-treatments, and nutrient medium combinations that are considered in haploid production via ovary culture in four commercial cucumber varieties. Four different induction media with four distinct maturation medium combinations and three F1 and one open-pollinated (Beith Alpha) cucumber varieties were used. All explants (cucumber ovaries' slices) were inoculated in induction media and remained at 35 °C/3 d in the dark, then were transferred at 25 ± 1 °C 16-/8-h light/dark photoperiod for a further 9 d. The results of the study demonstrated that the embryo-like structure (ELS) formation rate was high in induction medium 2 which was successful in all varieties of Ptk40 (20%), Botanik (20%), Beith Alpha (16%), and Sardes (13.3%), respectively, compared to other induction medium combinations used in this study. Callus formation rates obtained from regeneration of medium 2 supplemented with 2.0 mg L−1 6-benzylaminopurine (BAP) and 0.5 mg L−1 1-naphthaleneacetic acid (NAA) were Ptk40 (65%), Sardes (60%), and Botanik (40%), and no callus was formed in Beith Alpha. Due to the findings of this study, the nutrient medium containing KIN and 2,4-D seems to be successful during induction of haploid embryo formation in cucumbers. One plantlet germinated but perished at early stage. The plantlet regeneration was observed to be low. Further studies are required to optimize the embryo regeneration medium composition due to the cucumber growing seasons, genotypes, and nutrient medium. [ABSTRACT FROM AUTHOR]

Cytochrome P450s are a large family of protein-encoding genes in plant genomes, many of which have not yet been comprehensively characterized. Here, a novel P450 gene, CYP82D47, was isolated and functionally characterized from cucumber (Cucumis sativus L.). Quantitative real-time reverse-transcription polymerase chain reaction analysis revealed that CYP82D47 expression was triggered by salicylic acid (SA) and ethephon (ETH). Expression analysis revealed a correlation between CYP82D47 transcript levels and plant defense responses against powdery mildew (PM) and Fusarium oxysporum f. sp. cucumerinum (Foc). Although no significant differences were observed in disease resistance between CYP82D47-RNAi and wild-type cucumber, overexpression (OE) of CYP82D47 enhanced PM and Foc resistance in cucumber. Furthermore, the expression levels of SA-related genes (PR1, PR2, PR4, and PR5) increased in CYP82D47-overexpressing plants 7 days post fungal inoculation. The levels of ETH-related genes (EIN3 and EBF2) were similarly upregulated. The observed enhanced resistance was associated with the upregulation of SA/ETH-signaling-dependent defense genes. These findings indicate the crucial role of CYP82D47 in pathogen defense in cucumber. CYP82D47-overexpressing cucumber plants exhibited heightened susceptibility to both diseases. The study results offer important insights that could aid in the development of disease-resistant cucumber cultivars and elucidate the molecular mechanisms associated with the functions of CYP82D47. [ABSTRACT FROM AUTHOR]

Compost has a broad application in terms of the improvement of the soil properties. This research work was conducted to present the molecular implications of using compost obtained from different substrates to improve soil parameters for cucumber seedlings cultivation. In the experiment, the following compost mixtures were used: sewage sludge (80%) + sawdust (20%); sewage sludge (40%) + sawdust (10%) + biodegradable garden and park waste (50%); biodegradable garden and park waste (90%) + sawdust (10%); sewage sludge (80%) + sawdust (20%) + Eisenia fetida; sewage sludge (40%) + sawdust (10%) + biodegradable garden and park waste (50%) + Eisenia fetida; biodegradable garden and park waste (90%) + sawdust (10%) + Eisenia fetida. The final substrate compositions consisted of compost mixtures and deacidified peat(O) (pH 6.97; Corg content—55%, N content—2.3%), serving as a structural additive, in different mass ratios (mass %). The produced plants underwent biometric and physiological measurements as well as enzymatic analyses of stress markers. Based on the conducted studies, it has been found that the substrate productivity depends not only on the content of nutrient components but also on their structure, which is moderated by the proportion of peat in the substrate. The most effective and promising substrate for cucumber seedling production was variant 2 (I), which consisted of 25% compost from sewage sludge (40%) + sawdust (10%) + biodegradable garden and park waste (50%) and 75% deacidified peat. Despite the richness of the other substrates, inferior parameters of the produced seedlings were observed. The analysis of the enzymatic activity of stress markers showed that these substrates caused stress in the plants produced. The study's results showed that this stress was caused by the presence of Eisenia fetida, which damaged the developing root system of plants in the limited volume of substrate (production containers). The adverse influence of Eisenia fetida on the plants produced could possibly be eliminated by thermal treatment of the compost, although this could lead to significant changes in composition. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Cucumber is an important vegetable crop, and grafts often affect the quality and wax loss in cucumber fruit and affect its value. However, their metabolites and molecular mechanisms of action remain unclear. Metabolome and transcriptome analyses were conducted on the fruit peels of self-rooted plants (SR) grafted with white seed pumpkin (WG). The results showed that there were 352 differential metabolites in the fruit peels of the SR and WG. The transcriptome analysis showed 1371 differentially expressed genes (DEGs) between the WG and SR. These differentially expressed genes were significantly enriched in plant hormone signal transduction, cutin, suberin, wax biosynthesis, phenylpropanoid biosynthesis, and zeatin biosynthesis. By analyzing the correlation between differential metabolites and differentially expressed genes, six candidate genes related to the synthesis of glycitein, kaempferol, and homoeriodictyol were identified as being potentially important. Key transcription factors belonging to the TCP and WRKY families may be the main drivers of transcriptional changes in the peel between the SR and WG. The results of this study have provided a basis for the biosynthesis and regulation of wax loss and quality in grafted cucumbers and represents an important step toward identifying the molecular mechanisms of grafting onto cucumber fruit. [ABSTRACT FROM AUTHOR]

[Objective] The paper aims to explore whether calmodulin-like CMLs participate in the sexual differentiation process in Cucumis sativus L., so as to provide reference for improving the regulatory network of sexual differentiation furtherly. [Method] In the study, CMLS, ACSIG, ACS2 and ACS11 genes of cucumber were cloned, qPCR was used to detect the expressions of CMLS gene in different types of the flowers, and the interactions between CMLS and proteins encoded by major genes of cucumber sex differentiation were detected by the method of yeast two-hybrid. [Result】 CML8 was cloned from cucumber which contained a complete ORF of 441 bp, encoding 146 aa without signal peptide. It was an extracellular protein without transmembrane domain and introns, and contained 4 EF-hand domains with Ca2+ binding ca- pacity, and subcellular was located in cell membrane and cytoplasm. ACSIG, ACS2 and ACSII, three key genes of cucumber sexual differ- entiation were cloned, and sequence alignment showed that the nucleotide sequences and encoded protein sequences of the three genes were consistent with those in the cucumber database. There were significant differences in the expression levels of three genes in the female flow- ers, male flowers and bisexual flowers, and extremely significant differences in male flowers. The yeast two-hybrid experiment showed that CMLS could interact with ACSIG and ACS2, but not with ACS11. [Conclusion] Calmodulin-like 8 (CMLS) was cloned, and CMLS could interact with ACSIG and ACS2, which might participate in the sexual differentiation of cucumber, and the study was the first time to explore the involvement of calmodulin in the process of plant sexual differentiation, and expect to provide reference for calcium signaling system to participate in the process of plant sexual differentiation. [ABSTRACT FROM AUTHOR]

Horticulture is now revolutionized by advancements in light-emitting diode (LED) lighting. New technologies enable knowledge expansion on how plants require different spectral illumination for optimal growth and development. The aim of this study was to evaluate the quality of cucumber (Cucumis sativus L. ‘Parys F1’) and tomato (Solanum lycopersicum L. ‘Poranek’) seedlings produced in indoor controlled conditions, using three different types of LED tubes emitting warm light (AP67, AP673L, and G2). The photosynthetic photon flux density was set at 50–65 μmol m−2 s −1 and a 16-hour light regime was used. The results were compared to the cool daylight-emitting fluorescent (FL) control (tube lamp TLD 36W/54). A detailed analysis of the biometrical parameters of the aboveground and underground parts of seedlings was performed. Moreover, the content of chlorophyll in the leaves was measured. No effect of light spectra on the underground part of cucumber was found. On the other hand, the type of lamp affected the number of leaves and chlorophyll content in this species. Lamps AP673L and FL can be recommended in the production of cucumber seedlings. The obtained seedling had characteristics desired for horticultural production, i.e., compact habit with a fair number of leaves and chlorophyll content. As for tomato, the FL lamp had the best effect on the development of seedlings. Due to the high share of far red light, the tested LEDs stimulated the elongated growth of flaccid plants, unsuitable for commercial producers. Our findings not only described the effect of various light spectra on plant development but can also be useful for producers of popular vegetable crops. [ABSTRACT FROM AUTHOR]

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

The use of high-quality seedlings is a key factor for the success of the vegetable production system, and the use of plant growth-promoting bacteria (PGPB) can be decisive for the production of quality cucumber seedlings. Seeds from two cucumber cultivars (Aodai Melhorado and Marketmore76) were used to investigate the effectiveness of applying inoculant rates containing Azospirillum brasilense to improve germination rate and initial seedling growth. Seeds previously inoculated with inoculant containing the strains AbV5 and AbV6 of A. brasilense [0 (control), 4, 8, and 16 mL kg-1 of seed] were placed to germinate in a germination chamber at 25°C for 8 days. The experimental design used was completely randomized in a 2 x 4 factorial scheme, with four replications of 50 seeds. The results reported that the inoculant application containing the strains AbV5 and AbV6 of A. brasilense reduced germination percentage and germination rate index, whereas the inoculation of A. brasilense resulted in an increase in the mean germination time, especially for the Marketmore76 cultivar. The inoculation of seeds with A. brasilense has little effect on the shoot and root growth of cucumber seedlings. The negative and positive effects of the application of A. brasilense on the growth of cucumber seedlings are dependent on the genotype used. These results indicate that further studies should be conducted to investigate other application methods and use of other strains of A. brasilense to prove the beneficial effects of using these PGPB in improving the quality of cucumber seedlings. [ABSTRACT FROM AUTHOR]

Population-specific, positive selection promotes the diversity of populations and drives local adaptations in the population. However, little is known about population-specific, recent positive selection in the populations of cultivated cucumber (Cucumis sativus L.). Based on a genomic variation map of individuals worldwide, we implemented a Fisher's combination method by combining 4 haplotype-based approaches: integrated haplotype score (iHS), number of segregating sites by length (nSL), cross-population extended haplotype homozygosity (XP-EHH), and Rsb. Overall, we detected 331, 2,147, and 3,772 population-specific, recent positive selective sites in the East Asian, Eurasian, and Xishuangbanna populations, respectively. Moreover, we found that these sites were related to processes for reproduction, response to abiotic and biotic stress, and regulation of developmental processes, indicating adaptations to their microenvironments. Meanwhile, the selective genes associated with traits of fruits were also observed, such as the gene related to the shorter fruit length in the Eurasian population and the gene controlling flesh thickness in the Xishuangbanna population. In addition, we noticed that soft sweeps were common in the East Asian and Xishuangbanna populations. Genes involved in hard or soft sweeps were related to developmental regulation and abiotic and biotic stress resistance. Our study offers a comprehensive candidate dataset of population-specific, selective signatures in cultivated cucumber populations. Our methods provide guidance for the analysis of population-specific, positive selection. These findings will help explore the biological mechanisms of adaptation and domestication of cucumber. [ABSTRACT FROM AUTHOR]

The plant lipoxygenase cascade is a source of various regulatory oxylipins that play a role in cell signalling, stress adaptation, and immune response. Recently, we detected an unprecedented 16(S)-lipoxygenase, CsLOX3, in the leaves and fruit pericarp of cucumber (Cucumis sativus L.). In the present work, an array of products biosynthesized through the conversions of α-linolenic acid 16-hydroperoxide (16-HPOT) was detected. Firstly, a prominent 15-hydroxy-9,12-pentadecadienoic acid (Me/TMS) was detected, the product of hydroperoxide lyase (HPL) chain cleavage of 16-HPOT and further reduction of aldehyde 15-oxo-9,12-pentadecadienoic acid to alcohol. Besides, the presence of dicarboxylic acid, 3,6-pentadecadiene-1,15-dioic acid, was deduced from the detection of its catalytic hydrogenation product, pentadecane-1,15-dioic acid. Finally, 12,15-dihydroxypentadecanoic acid (Me/TMS) was detected amongst the hydrogenated products, thus indicating the presence of the parent 12,15-dihydroxy-9,13-pentadecadienoic acid. To confirm the proposed HPL chain cleavage, the 16(S)-HPOT was prepared and incubated with the recombinant cucumber HPL CYP74B6 enzyme. The CYP74B6 possessed high activity towards 16-HPOT. Chain cleavage yields the (9 Z ,12 Z)-15-oxo-9,12-pentadecadienoic acid, undergoing a spontaneous isomerization into (9 Z ,13 E)-15-oxo-9,13-pentadecadienoic acid. Thus, the cucumber plants as well as the recombinant cucumber HPL CYP74B6 possessed unprecedented 16-HPL activity, cleaving 16-HPOT into a C 15 fragment, 15-oxo-9,12-pentadecadienoic acid, and a complementary volatile C 3 fragment, propionic aldehyde. The 16-LOX/16-HPL route of oxylipin biosynthesis presents a novel facet of the plant LOX pathway. The products of 16-hydroperoxide lyase were detected in cucumber leaves and fruit pericarp. Cucumber CYP74B6 and CYP74C1_CS enzymes catalyze the conversion of 16-hydroperoxide of α-linolenic acid resulted in the formation of a C15 and a complementary C3 fragments. [Display omitted] • Novel 16-lipoxygenase/hydroperoxide lyase route was detected in cucumber plants. • Recombinant CYP74B6 and CYP74C1_CS possessed 16-hydroperoxide lyase activity. • Both enzymes cleaved α-linolenate 16-hydroperoxide into C 15 and C 3 fragments. • Detected 16-hydroperoxide lyases produced 15-oxo-9,12-pentadecadienoic acid. [ABSTRACT FROM AUTHOR]

This research hypothesized that tolerance of cucumber seedlings to salinity stress could be increased by hydrogen sulfide (H2S) treatments. In pot experiments, the cucumber seedlings were exposed to three levels of salt stress (0, 50 and 100 mM NaCl), and NaHS as H2S donor was foliar applied to the cucumber seedlings at five different doses (0, 25, 50, 75 and 100 µM). The effects of the treatments on cucumber seedlings were tested with plant growth properties as well as physiological and biochemical analyses. As the salinity level increased, plant growth properties and chlorophyll reading value (SPAD) decreased. However, H2S treatments significantly mitigated the impact of salinity. Salt stress elevated the membrane permeability (MP) and decreased the leaf relative water content (LRWC). H2S applied leaves had lower MP and higher LRWC than non-H2S applied leaves. On the other hand, photosynthetic properties (net photosynthetic rate, stomatal conductance, transpiration rate and intercellular CO2 concentration) of the seedlings under salt stress conditions were decreased but this decrease was considerably relieved by H2S treatment. The K/Na and Ca/Na ratios under salt stress conditions were higher in H2S-applied plants than in non-applied plants. Furthermore, antioxidant enzyme activity [(catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD)] and hydrogen peroxide (H2O2), malondialdehyde (MDA), proline, and sucrose concentration in the leaves increased with salinity stress whereas they were reduced with H2S treatments under salt stress. Mitigation of salt stress damage in cucumber using H2S treatment can be expounded via modulation of enzyme activity, nutrient content, reactive oxygen species (ROS) formation, and osmolytes accumulation. [ABSTRACT FROM AUTHOR]

Cucumber is a species appreciated in cooking, in addition to providing various nutrients for health. In view of this, it is important that research on its growth is carried out, prioritizing statistical analyzes that effectively demonstrate the results. The objective was to verify the differences by analyzing of the variance and nonlinear models, in addition to characterizing the production, early production and production rate of cultivars of cucumber using of nonlinear models. An experiment was carried out in a randomized block design (RBD), with three cultivars ('Atlantico', 'Caipira' and 'Fuyu') in six replications. Two types of analysis of variance were performed for the variable mass of cucumber fruits. In the first the RBD design was considered with three cultivars and six replications and in the second the RBD design was considered in a split subdivided over time (cultivars x harvests). Afterwards, the Logistic growth model was adjusted for the fruit mass variable as a function of accumulated thermal sum, and determination of the critical points of the model. The use of nonlinear models to evaluate experiments with cultures of multiple harvests has advantages in relation to anova and complementary tests. The cultivar 'Fuyu', has higher productivity compared to the cultivars 'Atlantico' and 'Caipira', in addition to presenting greater precocity and production rate. The adjustment of the logistic model and its critical points allowed to identify the production, precocity and production rate of the evaluated cultivars of the cucumber. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The purpose of this study was to verify the effect of growing season and nitrogen doses on the pickling cucumber. This work was carried out in a greenhouse at the Federal Institute of Goiás (IF Goiano) - Campus Urutaí. A randomized block design in a 2 x 5 factorial scheme with four replications was used. Two growing seasons (the first sown in January and second in April) and five nitrogen doses (0, 50, 100, 150, and 200 kg ha-1 of N) were evaluated. The seed of pickling cucumber used was the Kybria F1 hybrid. Nitrogen doses were applied at 15, 30, and 45 days after plant emergence. Each plot was composed of 10 plants, and the four central plants of each plot with a spacing of 0.2 m between plants and 0.8 m between rows were evaluated. Leaf nitrogen content, relative chlorophyll index, stem diameter, length and diameter of fruits, fresh and dry matter of fruits, the fresh matter of shoot, number of fruits, and yield per plant were evaluated. The growing seasons and nitrogen doses influenced the productive traits of the cucumber crop. The first growing season of the cucumber crop shows satisfactory results in terms of yield components at a dose of 100 kg ha-1 of nitrogen. [ABSTRACT FROM AUTHOR]

This study aimed to assess the growth, nutrition and visual deficiency symptoms of cucumber plants as a function of macronutrient omission. The experiment was conducted in a completely randomized design, with seven treatments and four replicates, corresponding to nutrient solution without nutrient omission (CS) of Hoagland and Arnon, nitrogen (−N), phosphorus (−P), potassium (−K), calcium (−Ca), magnesium (−Mg) and sulfur (−S) omission. Omissions decreased the accumulation of macronutrients with detrimental effects in physiological variables and in the efficiency of absorption, transport and use of macronutrients, causing losses in growth and on dry mass production. Since the losses in dry mass in the shoot were up to 85%, 85%, 83%, 47%, 40% and 40% to the omission of Ca, Mg, N, P, K and S, respectively. The accumulation of macronutrients in the aerial part of cucumber plants that received the complete solution (CS) in relation to each omission (−) was 1058/75, 157/20, 958/152, 578/9, 147/5 and 142/12 for CSN/−NN, SCP/−PP, SCK/−KK, SCCa/−CaCa, SCMg/−MgMg and SCS/−SS, respectively. Therefore, the lowest macronutrients accumulation, the green color index, plant growth and dry matter production were reduced in cucumber plants. The order of limitation of macronutrients in the shoot dry matter production in cucumber plants was N = Ca = Mg > P > K = S. [ABSTRACT FROM AUTHOR]

Aluminum (Al) is an ubiquitously present element in soil; it is considered as a major problem in crop production that affects plant growth and development on acid soils. The aim of this work was to determine the germination parameters, to quantify the water status and growth, to assess the Al accumulation, and antioxidant enzyme activities in plants to evaluate the stress exerted by aluminum in Cucumis sativus L. For germination test, increasing doses of Al were used (0, 200, 500, 1,000, and 2,000 μM). Results showed that germination was stimulated with 500 of Al. Aluminum effects on development were studied by treating the plants with different concentrations of Al (100, 200, 300, and 500 µM, Al) during 45 days. As regards to the plant's growth, water content, and dry biomass production there was a slight increase. On the other hand, the activities of the antioxidant enzymes were disturbed by aluminum stress. Data indicate that the catalase (CAT) activity showed a decrease in the different parts of the plant. However, guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) activities were significantly stimulated. Studying the effects of Al‐induced stress allowed us to conclude that cucumber has a high ability to accumulate this element in the roots. [ABSTRACT FROM AUTHOR]

• Extended shelf-life is a complex trait and retention of green colour (RGC) is a major contributing trait. • RGC is controlled by single recessive gene and other contributing traits are polygenically controlled. • One major QTL in chromosome 4 spanning in region of 5.01 Mb was identified for RGC. • Csa_4G000860 and Csa_4G016490 are two possible candidate genes associated with RGC. Cucumber is a perishable vegetable crop with limited storability, and development of genotypes with extended shelf-life will help in reducing post-harvest loss. One natural variant, DC-48 with extended shelf-life, was used to understand the genetics of the associated traits and identify the genomic regions and associated candidate genes. Scanning electron microscopy revealed differences in the structure of the epicarp in the genotypes. Programmed cell death (PCD) and appearance of senescence-related dark spots (SRDS) in the epicarp of the cucumber fruit with low shelf-life were also detected. Retention of green colour, absence of any shrinkage, retention of fruit firmness and slow change in the pH of the endocarp were essential traits associated with extended shelf-life. Single recessive gene govern retention of green colour while the remaining traits were polygenic. One QTL detected through QTL-seq on chromosome 4 was associated with retention of green colour spanning over a region of 5.01 Mb. Conventional mapping in F 2 progenies with PCR-based markers also identified one QTL within the same region. RNA-seq and RT-PCR analysis at two different developmental stages revealed two genes in the QTL region namely, Csa_4G000860 with unknown function and Csa_4G016490 with acyl-transferase activity in the early and late developmental stages of the fruit, respectively associated with retention of green colour. Two PCR-based markers, InDel 861 and InDel 016, closely linked with retention of green colour can be used in marker-assisted back-cross introgression. This study provides greater insight into the molecular network associated with extended shelf-life in cucumber. [ABSTRACT FROM AUTHOR]

Summary: The fruit trichomes of Cucurbitaceae are widely desired in many Asian countries and have been a key determinant of cucumber (Cucumis sativus L.) cultivar selection for commercial production and breeding. However, our understanding of the initiation and development of cucumber trichomes is still limited. Here, we found that the cucumber TINY BRANCHED HAIR (TBH) gene is preferentially expressed in multicellular trichomes. Overexpression of CsTBH in tbh mutants restored the trichome phenotype and increased the percentage of female flowers, whereas silencing of CsTBH in wild‐type plants resulted in stunted trichomes with a lower rate of female flowers. Furthermore, we provide evidence that CsTBH can directly bind to the promoters of cucumber 1‐Aminocyclopropane‐1‐Carboxylate Synthase (CsACS) genes and regulate their expression, which affects multicellular trichome development, ethylene accumulation, and sex expression. Two cucumber acs mutants with different trichome morphology and sex morphs compared with their near‐isogenic line further support our findings. Collectively, our study provides new information on the molecular mechanism of CsTBH in regulating multicellular trichome development and sex expression through an ethylene pathway. Significance Statement: We explored the role of CsTBH in cucumber (Cucumis sativus L.) trichome development by directly activating CsACS genes, providing new information on the molecular mechanism of CsTBH functioning in multicellular trichome development and sex expression through an ethylene pathway. [ABSTRACT FROM AUTHOR]

Barium (Ba) is a nonessential element that can cause several deleterious effects in most organisms. Elevated Ba concentrations can be toxic for plants and may affect growth and disturbances in homeostasis. This study aimed to evaluate the Ba stress, the plant‐tolerance limits, and the detoxification strategy adopted by Cucumis sativus L. The effect of Ba on seed's germination and vegetative development of this species was evaluated. For germination test, different Ba concentrations were used (0, 200, 500, 1,000, and 2,000 μM). Results showed that germination was stimulated with 500 and 2,000 µM of Ba. The toxicity effect on plant development was studied by treating the plants with increasing doses of Ba (100, 200, 300, and 500 μM) during 45 days. Shoot and root dry biomass production decreased significantly with elevated Ba concentrations, although water content enhanced in the roots. The concentration of Ba, 500 µM, induced high Ba accumulation in shoots and roots (9 times higher than in the control plants). Moreover, results showed that catalase, guaiacol peroxidase, and ascorbate peroxidase activities were stimulated in the different tissues of cucumber plants which highlight the occurring of an oxidative damage through Ba treatments and the involvement of the plant enzymatic antioxidant defense system. [ABSTRACT FROM AUTHOR]

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 development 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. [ABSTRACT FROM AUTHOR]

In order to produce organic products, we conducted research on the properties of herbal extracts based on Rheum officinale Baill. (Polygonaceae) and Azadirachta indica Juss. (Meleaceae). The purpose of the work was to determine the possibility of using bioactive substances of plant extracts as a means of protecting the seedlings of Cucumis sativus L. from powdery mildew. We studied microscopically, powdery mildew pathogens Golovinomyces cichoracearum (de Candolle) Heluta, (Ascomycetes) identified on cucumbers and created a suspension for artificial infection. Extracts of R. officinale roots and leaves exhibited immunostimulating, fungicidal and phytostimulating types of activity. We found that the biological effectiveness of rhubarb root extract (73,3-86,7%) and neem extract (93,3-100%) does not depend on the time between treatment and infection, but increases in direct proportion to the concentration. It was found that, under greenhouse conditions, the biological effectiveness of the neem extract (100%) and the composition of rhubarb root and leaf extracts (86,7-100%) when treated 4 hours before the seedlings were infected, was maximum. Rhubarb leaf extract is antiseptic and has no immunostimulating properties. Bioactive substances of plant extracts had an active phytostimulating effect on plants of Cucumis sativus seedlings. The composition V6 (1% R + 0,5% L) showed the maximum phytostimulating effect, which significantly increased plant growth by 34,5% and increased the number of flowers by 89,6% in comparison with the control variant. Extracts represent a worthy alternative for synthetic plant growth regulators due to their environmental friendliness, ease of use, effectiveness and safety. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to isolate soilborne AHL degrading actinobacteria that can be used as biocontrol agents against the quorum sensing mediated virulence of Pectobacterium carotovorum subsp. carotovorum BR1 in in vitro and in planta studies. Methods: Actinobacterial strains capable of N-acyl homoserine lactone (AHL) degradation, Glutamicibacter nicotianae AI5a and Rhodococcus pyridinivorans AI4 were isolated and screened using Chromobacterium violaceum CV026 as a biosensor in an AHL degradation bioassay. The effect of AHL degradation by the potential biocontrol strains was studied by a co-culture assay. Reduction in plant cell wall degrading enzymes produced by PccBR1 due to the quorum quenching activity of the potential biocontrol strains was studied using colorimetric assays. The ability of the isolates to reduce soft rot symptoms was studied in in vitro cucumber and potato maceration assays. A cucumber plant infection model was developed to study blackleg in greenhouse experiments. Results: G. nicotianae AI5a, R. pyridinivorans AI4 and R. erythropolis CRD13.3C were able to reduce 3-oxo-C6- N-acyl homoserine lactone and production of plant cell wall degrading enzymes by PccBR1. The isolates were also able to prevent and attenuate soft rot caused by PccBR1 in vitro in potato and cucumber maceration assays. The isolates were also able to prevent blackleg in an in planta cucumber infection model. Conclusions: Among the three actinobacterial isolates, G. nicotianae AI5a showed best results and has immense potential as a biocontrol agent against the virulence of the quorum sensing phytopathogen PccBR1. [ABSTRACT FROM AUTHOR]

Resistance to disease in plants requires the coordinated action of multiple functionally related genes, as it is difficult to improve disease resistance with a single functional gene. Therefore, the use of transcription factors to regulate the expression of multiple resistance genes to improve disease resistance has become a recent focus in the field of gene research. The basic leucine zipper (bZIP) transcription factor family plays vital regulatory roles in processes, such as plant growth and development and the stress response. In our previous study, CsbZIP90 (Cucsa.134370) was involved in the defense response of cucumber to Podosphaera xanthii , but the relationship between cucumber and resistance to powdery mildew remained unclear. Herein, we detected the function of CsbZIP90 in response to P. xanthii. CsbZIP90 was localized to the cytoplasm and nucleus, and its expression was significantly induced during P. xanthii attack. Transient overexpression of CsbZIP90 in cucumber cotyledons resulted in decreased resistance to P. xanthii , while silencing CsbZIP90 increased resistance to P. xanthii. CsbZIP90 negatively regulated the expression of reactive oxygen species (ROS)-related genes and activities of ROS-related kinases. Taken together, our results show that CsbZIP90 suppresses P. xanthi resistance by modulating ROS. This study will provide target genes for breeding cucumbers resistant to P. xanthii. • CsbZIP90 is involved in the immune defense of cucumber against Podosphaera xanthii. • CsbZIP90 transgenic plants modulate the expression levels of CsPR1-a, CsPR2 and CsPR3. • CsbZIP90 negativity regulated reactive oxygen species to enhanced the resistance of cucumber to Podosphaera xanthii. [ABSTRACT FROM AUTHOR]

Seed production depends on many factors. In this study, two independent experiments were carried out to investigate the effects of pollination time, crossed node spacing, male flower age, number of crossings on each plant and deletion/non-deletion of other fruits in the crossed nodes on the cross-ability and seed production in greenhouse cucumber. In every experiment, three mentioned factors were assayed based on factorial experiment as a randomized complete block design. Crosses were done on 10 plants in every replication of treatments. The results showed that pollination at 8:00-9:45 AM, led to higher amount of full seed weight in contrast to other times of pollination. Increasing crossed node spacing from 2-3 to 4-5 nodes led to an increase in the number of empty seeds, which was ascribed to the reduced seed production. The highest amount of number of seeds per fruit, seed weigh and number of full seeds were obtained when young male flowers were used. Moreover, higher seed production was obtained from five, instead three crossings on each plant, and the non-deletion of fruits on the crossed nodes. Overall, higher percentage of seed production per fruit was obtained when crossing was done with young male flower in early morning and high number of crossing in every plant. [ABSTRACT FROM AUTHOR]

Abstract This paper investigates the physiological mechanism of the effect of delaying cucumber senescence on protein levels under the experimental model of monoculture and wheat intercropping. We analyzed cucumber roots for differential protein expression, and protein types were identified by core technology of proteomics. 45 differential proteins were identified as being differentially expressed between monoculture and intercropping of wheat, which were involved in carbohydrate metabolism, antioxidant and stress response, growth and development regulation, biological information transfer, and nucleic acid biosynthesis. The results showed the rate of photosynthesis of cucumber was increased under wheat intercropping pattern due to three enzymes being up-regulated. The respiration of cucumber was reduced when five enzymes were down-regulated. The antioxidant and resistant capacity of cucumber was enhanced significantly under wheat intercropping pattern because two enzymes were down-regulated while the activity of four other antioxidant enzymes was up-regulated. Intercropping wheat could delay the senescence of cucumber leaves by increasing the expression of IPT gene, reducing the expression of PAO and ETR2 gene, and inhibiting the expression of Cu/Zn-SOD and GS1 gene in later stages. Two proteins related to growth and development in cucumber were up-regulated, and one was down-regulated, while two proteins related to nucleic acid biosynthesis and chaperonin showed obvious down-regulation under wheat intercropping. Therefore, the growth and development was improved and senescence of cucumber could be delayed. Under intercropping pattern, the fresh weight, chlorophyll content, photosynthetic rate, and peroxidase activity of cucumber plants were higher than those of cucumber monoculture groups. Thus, the senescence of cucumber could be delayed under wheat intercropping by regulating its physiological mechanisms, such as by improving photosynthesis, reducing respiratory consumption, slowing the cell apoptosis rate, and enhancing the antioxidant and resistant capacity significantly, etc. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Tropical fruit crops often respond differently to limiting growth conditions under varying extremes of environmental conditions. • Repeated-Measure and Principal Component Analysis showed that the juvenile pawpaw responses had no influence on the mature pawpaw plants. • The influence of excessive moisture and low temperature were not conducive for the vegetative and reproductive growth of the cucumber intercrop. • Low temperature and high moisture significantly improved the flowering response of pawpaw, but caused retardation effect to the fruit production. • Strategic manipulation of the micro-environment could augment the crops moisture and temperature needs for improved crop performance. Abstract Tropical fruit crops often respond differently to limiting growth conditions under varying extremes of environmental conditions. Field experiments conducted in Abeokuta, Nigeria evaluated the influence of seasonal variations on two pawpaw (Carica papaya L.) varieties ('Sunrise solo' and 'Homestead selection') in cropping mixture with cucumber (Cucumis sativus L.) var. 'Market-more' (pawpaw-cucumber mixed or planted sole) across three seasons. Repeated-measures analysis (RM), Principal Component Analysis (PCA) and Two-Way analysis of variance were used for the evaluation of the 3 × 2 × 2 factorial experiment arranged in randomized complete block design replicated thrice. The results showed that juvenile pawpaw in year-two environmental conditions of moderate precipitation and higher temperature, and mature pawpaw in year-three of higher precipitation and moderate temperature had improved vegetative growth performances, yet in reproductive growth pawpaw in year-two through interplay of precipitation and lower temperature obtained more flowers, higher fruit setting rate and heavier fruit yield than those in years-one or –three. Taller plant with thicker girth and wider canopy was observed for juvenile homestead compared to sunrise; but no difference at mature pawpaw stage. Both RM and PCA analysis showed that most times performances of juvenile pawpaw had no influence on mature pawpaw. In reproductive growth, sunrise had more flowers, higher fruit setting rate and heavier fruit yield compared to homestead. Except in leaf area responses at juvenile stage, sole pawpaw had taller plants, thicker girth and wider canopy compared to mixed pawpaw, but no significant difference among crop mixtures at mature pawpaw stage. Cucumber intercrop significantly improved flowering responses but caused retardation to fruit yield. Although >1.0 LER indicated improved productivity of the mixtures compared to sole, there was no significant difference among the seasonal LERs (1.41, 1.44 and 1.47), and the pawpaw varieties (1.36 and 1.51). [ABSTRACT FROM AUTHOR]

In this study cucumber (Cucumis sativus L.) plants grown in greenhouse conditions were treated with different concentrations (Recommended dose = 0.4 ml L-1 water, twice the recommended dose (x2) = 0.8 ml L-1 water and three times (x3) = 1.2 ml L-1 water) Cypermethrin active insecticide. In addition to morphological measurements, germination percentages, total protein and proline quantities, photosynthetic pigment substances and endogen hormone content were also examined. The insecticide applied did not seem to be effective on germination of seeds. However, it was determined that it inhibited root elongation, one of the growth parameters. Chlorophyll a, b and total chlorophyll values decreased in x3 treatment group and increase in carotenoid values compared to the control group. Protein, proline, abscisic acid (ABA) and Indol-3 Acetic acid (IAA) values were found to increase in the x3 treatment group relative to control. According to these results; it has been determined that applied insecticide causes abiotic stress in cucumber plants especially with high concentrations. It has been shown that plant metabolism, growth and development are affected negatively by stress. [ABSTRACT FROM AUTHOR]

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 carbonsink strength was an important factor maintaining higher efficiency of photosynthesis in mycorrhizal cucumber seedlings under cold stress. [ABSTRACT FROM AUTHOR]

• Effect of cultivar on petiole sap [NO 3 −] and leaf N content examined in cucumber, melon and pepper. • Appreciable and consistent differences in sap [NO 3 −] between cultivars in cucumber and melon. • Smaller consistent differences in leaf N between cultivars in cucumber and melon. • Consistent differences between cultivars not observed in pepper. • Strong relationship between leaf N and on petiole sap [NO 3 −] in the three species. Excessive N fertilizer applications in intensive vegetable production in soil is commonly associated with appreciable N losses causing negative environmental impact. Measuring petiole sap [NO 3 −‒N] and leaf N content (%) are simple and practical monitoring methods to assess crop N status for improving N fertilizer management. The effect of cultivar on petiole sap [NO 3 −‒N] and leaf N content was evaluated. One cucumber, two melon, and two sweet pepper crops were grown in different cropping periods, with three cultivars in each crop. Three N treatments, deficient (N1), sufficient (N2) and excessive (N3) N supply, were applied by combined fertigation with drip irrigation. For a given N supply, there were often significant differences between cultivars in petiole sap [NO 3 −‒N] and leaf N content in cucumber, the two melon crops and one pepper crop. This was, particularly so with the sufficient (N2) and excessive (N3) N supply. In the cucumber and two melon crops, there were consistent differences in petiole sap [NO 3 −‒N] between cultivars in two or three of the different N treatments. In some crops, very little petiole sap [NO 3 −‒N] was measured with deficient (N1) N supply. In the two pepper crops, the differences between cultivars were less clear than with cucumber and melon. In general, for the three species examined, petiole sap [NO 3 − ‒ N] was subject to more consistent and larger effects between cultivars, than was leaf N. Average differences between cultivars in petiole sap [NO 3 − ‒ N] of 200‒450 mg NO 3 − ‒ N L−1 were observed during periods of 4‒6 weeks in cucumber and melon. The differences between different cultivars of the same species in petiole sap [NO 3 −‒N] and leaf N content, when receiving the same N supply, has implications for the practical applications of these methods for monitoring crop N status. [ABSTRACT FROM AUTHOR]

Black shading nets are widely used in the protected cultivation of vegetables as a technique for controlling light and temperature, while the colored shading nets, with special optical properties to improve the use of solar radiation, appeared recently in the agricultural plastics market. Light quality transmitted by gray, aluminized, pearl, blue, red and black (control) nets with 30% shade was evaluated, as well as its effects on photosynthetic properties and fruits production of cucumber plants. Treatments (shade nets) were established under a randomized complete block design with four repetitions. The red net transmitted 23.7 and 40.3% more photosynthetic photon flux density (400 to 700nm) and red light (600 to 700nm) and the blue net transmitted 36% more blue light (400 to 500nm) in comparison with the respective transmissions of black net. All nets increased the photosynthetic responses: transpiration, stomatal conductance and CO2 assimilation, observed in plants grown under black net. Leaf greenness (41.6 SPAD units) and foliar area (90dm²) increased 22.8 and 38.9% with the red net, while the dry weight of leaf (52.5g) increased 21.9% with pearl net. Pearl, red, aluminized and blue nets showed to be viable alternatives because the production of fruit increased in 71, 48, 46 and 46%, respectively, in comparison with the conventional black net (52t ha-1). [ABSTRACT FROM AUTHOR]

Microcystins (MCs) are released into the lake during the outbreak of cyanobacteria and could enter the farmland ecosystem by irrigating. This study investigated the effect of MCs on growth, yield and fruit quality of cucumber and evaluated the potential risk of MCs. Cucumber plants were irrigated daily for 7 days with MCs extraction contaminated water (0, 1, 10, 100, 1000 μg/l), and then, cultivated with uncontaminated water to final harvest. Results show that 10 μg/l MCs exposure inhibited the growth of cucumber at different growth stages, and the order of decreased degree in the growth of cucumber was seedling stage > early flowering stage > fruiting stage. Contents of vitamin C, soluble sugar and organic acid in fruits of cucumber exposed to10 μg/l MCs at seedling stage were decreased. MCs at concentrations of 100 μg/l and 1000 μg/l significantly decreased the growth of cucumber at different growth stages, and reduced cucumber yield at fruiting stage. There were even no fruits at seedling stage and early flowering stage. The estimated daily intake of MCs in fruits exposed to 100 μg/l and 1000 μg/l MCs at fruiting stage were 0.103 μg/kg and 0.198 μg/kg, exceeding WHO limit. It indicates that human should exercise care when ingesting cucumber fruit as a part of their diet and strengthen agricultural irrigation management to prevent cucumbers from irrigating with MCs contaminated water. [ABSTRACT FROM AUTHOR]

This experiment was carried out during two seasons; the first season 2016 included the planting of cucumber seeds from different global origins, which symbolized P1 and P2-P10 in a plastic house with (506 m2) area, at Yusufiya – Baghdad to produce hybrids. During Spring season 2017 the genotypes seeds were planted (10 parents and 27 single cross hybrids with codes F1 and F2-F27 and three common commercial control hybrids with codes C1, C2 and C3) according RCBD design with three replicates, The genotype P5 was superior in the branches number per plant (9.67) and number of leaves per plant (220.33) as well as in total yield of experimental unit 18.03 kg, The hybrid F17 (P5×P9) took lowest number of days number until first female flower appearance (34.00 days) and number of days until first harvest (37.67 days), as well as it produce the highest fruit weight 178.747 gm, the most of hybrids had significant heterosis, the hybrid F23 had the highest positive hybrid vigor in number of leaves per plant (73.03%), the hybrids F4, F17 and F19 had negative heterosis in number of days until first female flower appearance, eight hybrids had positive hybrid vigor in weight of fruit but 16 hybrids had heterosis in experimental unit yield and the highest value obtained from F27 67.77%, while in control hybrid vigor, 15 hybrids had the superiority in numbers of branches so the highest value obtained from F3 53.96%, also it had the highest value of control hybrid vigor in number of leaves per plant 93.21%, the hybrid F27 had significant control hybrid vigor in experimental unit yield 66.79%. [ABSTRACT FROM AUTHOR]

One of the available tools used to increase the productivity of crops is the mathematical modeling. This allows us to design management strategies without the need for expensive experiments; however, this technology has been applied mainly to tomato under greenhouse conditions. For other crops, there is not enough information available. As to generate the necessary information for the calibration and validation of a dynamic growth and mineral absorption model –originally implemented in tomato cultivation– two cycles of cucumber (Vitaly and Luxell varieties) were carried out mainly because cucumber stands out as one of the crops that is mostly grown under greenhouse conditions. Mineral analyzes (N, P and K) were performed to determine their behavior in the different cucumber organs during the development of the crop. The percentages of minerals contained in each organ and in the whole plant were obtained. These percentages were included in the mathematical model in order to dynamically simulate their behavior. The results show that the growth model output adequately simulates leaf and fruit weight ( EF  > 0.95 and Index  > 0.95), as well as indices above 0.95 for harvested fruit and leaves. Regarding minerals, indices above 0.90 were obtained, where N was the element that showed the lowest indices during the validation process of the model (0.90). This model can be useful to define adequate nutrition strategies for Vitaly and Luxell cucumber varieties. [ABSTRACT FROM AUTHOR]

Strobilurins are fungicides with beneficial physiological effects on crop yield due to promotion of net carbon assimilation, nitrate reductase enzyme activity, stress tolerance and hormonal balance. The carboxamides complement the action of the strobilurins when applied alternately or together. This study aimed to evaluate the effect of application of pyraclostrobin, azoxystrobin and boscalid on grafted and ungrafted Japanese cucumber ( Cucumis sativus L.) in order to analyze the effects of these fungicides on plant physiology and increased fruit production. The experimental design was completely randomized in a 2 × 5 factorial scheme, with grafted and ungrafted cucumber plants and 5 fungicide treatments: control; azoxystrobin 60 g a.i ha −1 ; boscalid 50 g a.i ha −1 ; pyraclostrobin 50 g a.i ha −1 ; and boscalid 100 g a.i ha −1 + pyraclostrobin 50 g a.i ha −1 , applied 18 days after transplanting and then at intervals of seven days. The effect of the treatments was evaluated based on the average yield and fruit mass, in addition to observations of gas exchange, lipid peroxidation, and the activities of peroxidase, superoxide dismutase, catalase and nitrate reductase. Based on the results obtained, it was concluded that the fungicide treatments resulted in different responses between the grafted and ungrafted plants. The physiological benefits were more evident in the grafted plants treated with pyraclostrobin or boscalid alone, and these benefits manifested in terms of fruit production and increased the activity of the antioxidative system, thereby reducing stress. The higher productivity probably occurred due to the better physiological performance of these plants, mainly at the beginning of development, presenting greater activity of the enzyme nitrate reductase, in addition to the higher net CO 2 assimilation and carboxylation efficiency. [ABSTRACT FROM AUTHOR]

The control of micronutrient application in cucumber cultivation has great importance as they participate in many functions of metabolism. In addition, micronutrient application efficiency is fundamental to avoid periods of overconsumption or deficits in the crop. To determine micronutrient accumulation using a dynamic model, two cycles of Vitaly and Luxell cucumber crops were grown. During the development of the crop, micronutrient content (Fe, B, Mn, Cu, and Zn) in the different organs of the cucumber plant was quantified. The model dynamically simulated the accumulation of biomass and micronutrients using climatic variables recorded inside the greenhouse as inputs. It was found that a decrease in photosynthetically active radiation and temperature significantly diminished the accumulation of biomass by the cucumber plants. On the other hand, the results demonstrated that the model efficiently simulated both the accumulation of biomass and micronutrients in a cucumber crop. The efficiency evaluation showed values higher than R² > 0.95. This dynamic model can be useful to define adequate strategies for the management of cucumber cultivation in greenhouses as well as the application of micronutrients. [ABSTRACT FROM AUTHOR]

To sense, respond and adapt to the constantly changing environmental conditions, plants have developed sophisticated signaling mechanisms. In this study, plant signaling under heterogeneous salt conditions was investigated. A split root system was established in which one half of the root apparatus (HR1) was treated with salt. The impact of the salt on the electrical signals as the initial response of the plant to exterior stimulus was measured in the other half of the root system (HR2) with a Multi Electrode Array (MEA) system. Duration and amplitude of the recorded electrical signals increased compared to the control. In order to identify the nature of the signal traveling from HR1 to HR2, H + and K + fluxes were measured in HR2 by using ion-selective microelectrodes (vibrating probe technique). A net potassium influx was observed after the treatment while no change in proton flux was detected. By corona sodium green and confocal microscopy we confirmed that changes in electrical signals and fluxes are not simply associated with apoplastic diffusion of sodium from HR1 to HR2. The activation of salt stress marker genes was also examined: the modulation of CsGOL-like expression seems to have systemic response, while ERF109 and aspartate oxidase showed localized responses. [ABSTRACT FROM AUTHOR]

Firmness of skin is an important quality of processing cucumbers, which is a feature of the palisade epidermis in these types compared to flat epidermis in fresh cucumbers. This study was conducted to map the Pe (palisade epidermis) and analyse the candidate gene. Populations derived from the cross of two inbred lines, NCG122 with fruit flat epidermis and NCG121 with fruit palisade epidermis, were used to identify the inheritance of palisade epidermis and to map the gene involved in its development. The results showed that the palisade epidermis trait is controlled by a single gene, Pe, that is dominant over flat epidermis. Seven simple sequence repeat ( SSR) and five insertion deletion (Indel) markers were identified to be linked to the Pe gene. It was mapped to cucumber chromosome 5 (Chr.5) between SSR14611 and Indelpe12 with genetic distances of 0.3 cM and 0.2 cM, respectively. The physical distance of the genomic region harbouring the gene was 227.5 kb with 26 predicted candidate genes. The accuracy of marker-assisted selection using the molecular markers, Indelpe12 and SSR14611, was 68% and 88%, respectively. [ABSTRACT FROM AUTHOR]

The genetic variation, marker attributes and population structure was assessed in 104 genotypes of cucumber using 23 SSR primer pairs. The total number of alleles produced was 67 with an average of 2.91 per locus. Allele frequency was in the range of 0.215 to 0.561 with mean value of 0.403, polymorphic information content ranged from 0.158 to 0.495 with the mean of 0.333, marker index ranged from 0.316 to 1.54 with an average value of 0.954 and resolving power ranged from 0.346 to 2.692 with mean of 1.392. The maximum allele frequency was reported with primer SSR65, whereas the maximum value of polymorphic information content and resolving power was found with SSR61 and the maximum value of marker index was reported with SSR60. Jaccard's similarity coefficient ranged from 0.07 to 0.897 with maximum similarity between genotype G40 and G41 and minimum between G16 and G20, and G16 and G100. Clustering and PCA grouped the genotypes in two clusters, and majority of them were found in cluster B. The population structure analysis also showed two major populations, in which 47 genotypes were found in population 1, 39 genotypes in population 2, whereas remaining 18 genotypes were admixtures. The study provides researchers a valuable information for genotype identification, gene mapping, molecular breeding, and future exploration of cucumber germplasm in India and other major cucumber growing countries. [ABSTRACT FROM AUTHOR]

Salinity is one of the abiotic stresses that further limit the seed germination and growth of plants because of low water potential of the soil. In this study, seeds of cucumber (Cucumis sativus L., cv. Aodai Melhorado) were used to investigate the effects of potassium nitrate priming on germination and early seedling growth under different salinity levels. It was hypothesized that priming with potassium nitrate may improve seed germination and plant establishment by mitigating the negative effects of saline stress through its role in cell osmotic balance. The seeds were soaked in distilled water or in a 2 g L-1 KNO3 solution at 25 °C for 6 hours, and after drying, were distributed in plastic boxes with blotter paper containing different salt solutions prepared with concentrations of 0 (control), 25, 50, 75 and 100 mmol NaCl L-1. The plastic boxes were kept into a seed germinator, at 25 °C for 10 days. A completely randomized design in a 2 x 5 factorial scheme with four replications of 25 seeds each was used. The results showed that the priming of cucumber seeds with potassium nitrate had little effect to improve germination capacity and growth rate of seedlings under salt stress conditions. Low salt concentrations may induce osmotic adjustment activity in the cucumber plants and lead to increases in hypocotyl and radicle length of seedlings, whereas higher concentrations cause severe inhibition of plant growth. The "Aodai Melhorado" cucumber cultivar is a moderately tolerant genotype to salt stress during the germination and seedling establishment stage by presenting yield stability index greater than 0.50 until the level of 100 mmol NaCl L-1. [ABSTRACT FROM AUTHOR]

The genetic variation, marker attributes and population structure was assessed in 104 genotypes of cucumber using 23 SSR primer pairs. The total number of alleles produced was 67 with an average of 2.91 per locus. Allele frequency was in the range of 0.215 to 0.561 with mean value of 0.403, polymorphic information content ranged from 0.158 to 0.495 with the mean of 0.333, marker index ranged from 0.316 to 1.54 with an average value of 0.954 and resolving power ranged from 0.346 to 2.692 with mean of 1.392. The maximum allele frequency was reported with primer SSR65, whereas the maximum value of polymorphic information content and resolving power was found with SSR61 and the maximum value of marker index was reported with SSR60. Jaccard's similarity coefficient ranged from 0.07 to 0.897 with maximum similarity between genotype G40 and G41 and minimum between G16 and G20, and G16 and G100. Clustering and PCA grouped the genotypes in two clusters, and majority of them were found in cluster B. The population structure analysis also showed two major populations, in which 47 genotypes were found in population 1, 39 genotypes in population 2, whereas remaining 18 genotypes were admixtures. The study provides researchers a valuable information for genotype identification, gene mapping, molecular breeding, and future exploration of cucumber germplasm in India and other major cucumber growing countries. [ABSTRACT FROM AUTHOR]

The main aim of this research was to characterize some plants and to determine their similarities and differences, using spectroscopic methods. The interactions of soluble polyphenols of different plants with human serum albumin (HSA) were investigated by 3D-fluorescence. The obtained fluorescence results allow to classify the investigated plants according to their binding properties. The HSA-binding capacities of these plants were the highest for asparagus and correlated with their antioxidant properties. To our knowledge this is the first report showing differences and similarities in these plants, using spectroscopic techniques. The fluorescence spectral methods, which were applied as a powerful tool showing the quenching properties of intrinsic fluorophores in protein molecules in the presence of some plant polyphenols, can contribute in pharmaceutical and food applications. [ABSTRACT FROM AUTHOR]

According to the second part of NY/T761—2008, the vinclozolin residue in cucumber was determined by GC. The sources of uncertainty components coming from the measuring process was analyzed. The mathematical model for the evaluation of measurement uncertainty was built and the uncertainty components were synthesized and expanded. The results showed that the relative combined standard uncertainty and expanded uncertainty of measurement results were 2.78% and 5.56% (k=2), respectively. The sources of measurement uncertainty mainly derived from diffusion and constant volume process of standard solution, the recovery rate in the extraction and purification process, and the error caused by the measurement of chromatographic peak area. The results of this study provide a reference for objective evaluation of the pesticide residue detemanation results. [ABSTRACT FROM AUTHOR]

In Mexico, Sphagnum turbe (peat moss) is the main substrate used for the production of vegetable seedlings in polystyrene trays. It is imported and thus has an elevated price, therefore some lower cost alternatives need to be addressed. This work proposes a mixture of peat with local organic materials as poultry manure (PM) and biosolid (B) to produce cucumber (Cucumis sativus L.) and zucchini (Cucurbita pepo L.) seedlings. Eight mixtures of organic material-peat were evaluated for each species: 1) 4% PM + 96% peat; 2) 8% PM + 92% peat; 3) 12% PM + 88% peat; 4) 16% PM + 84% peat; 5) 4% B + 96% peat; 6) 8% B + 92% peat; 7) 12% B + 88% peat; 8) 16% B + 84% peat, and 100% peat as control. Compared with the control, the mixture with 16% of biosolid affected positively SPAD (Soil Plant Analysis Development) units, stem diameter and leaf area in cucumber seedlings, while the mixture with 12% of poultry manure increased aerial and total dry weight (P ⩽ 0.05). In zucchini, the mixture with 16% of poultry manure increased leaf area (P ⩽ 0.05). No significant differences were found in height, root dry weight and seedling balance in both species and mixtures. We concluded that use of peat moss mixed with poultry manure or biosolid represents an important technical and economic alternative for cucumber and zucchini seedling production. [ABSTRACT FROM AUTHOR]