Search Results (29)

Grafting is a promising approach to control melon fusarium wilt disease. However, there is a potential risk of deterioration in the quality of melon fruit due to scion–rootstock interactions. Using two primary muskmelon cultivars, ‘ZheTian 105’ (ZT105) and ‘ZheTian 401’ (ZT401) in Zhejiang Province as scion, and taking one squash (interspecific hybrids between Cucurbita maxima and Cucurbita moschata) ‘Sizhuang No.12’ (SZ12) and four melon, ‘YongZhen No 9’ (YZ9), ‘XiaTe’ (XT), ‘ZhenTian No 1’ (ZT1), and ‘T1-151’ (T1) as rootstock, the yield and fruit quality including total soluble solid content (SSC), flesh texture, and flavor of grafted melon were measured, compared with non-grafted melon. The results indicated there was no significant difference in single fruit weight among the grafted melon and non-grafted melon plants, while the yield of most grafted melon plants was significantly higher than that of the non-grafted ones. No significant differences were observed in SSC and flesh texture among the grafted and non-grafted melon plants. The fruit of the “ZT401/SZ12” combination exhibited peculiar odors reminiscent of pumpkin flavor, negatively affecting edibility, whereas the fruit of the “ZT105/SZ12” combination did not. Considering both yield and fruit quality, the results indicated that the squash rootstock “SZ12” and the melon rootstocks “ZT1” are suitable for grafting with the muskmelon cultivar “ZT105”, while the melon rootstocks “ZT1” and “T1” are appropriate for grafting with the muskmelon cultivar “ZT401”. The results of this research are of considerable significance for the sustainable cultivation of the cultivars “ZT105” and “ZT401”, particularly under continuous cropping conditions. Full article

The oxidative stability of nutritive and bioactive lipids is essential for their functionality. This study evaluated the potential of lipid fractions from pumpkin seeds obtained from eleven high-performing cultivars of Cucurbita maxima Duchesne, C. pepo L., and C. moschata Duchesne cultivated in Poland, aiming to evaluate their stability for nutraceutical applications. This study investigated the intrinsic relationship between chemical composition and oxidative stability to identify cultivars with promising functional potential and commercial value. The fatty acid, sterol, and lipid antioxidant profiles were characterized using gas chromatography (GC), GC–mass spectrometry (GC-MS), and ultra-high-performance liquid chromatography (UPLC), respectively. Antiradical activity was assessed via the DPPH assay, and oxidative stability was evaluated using differential scanning calorimetry (DSC). The oils exhibited high levels of polyunsaturated fatty acids (PUFAs) (59.5–68.6%), with n-6/n-3 fatty acid ratios ranging from 66.5 to 211.6. The lipid extracts contained up to 97.1% Δ⁷-sterols, while key antioxidants included squalene (616.6–3092.0 mg/kg) and γ-tocopherol (54.1–423.6 mg/kg). Notably, the C. pepo cultivar ‘Moonshine’ was the least abundant in these bioactive compounds. The carotenoid content ranged from 5.7 to 19.4 mg/kg across the extracts. Among the studied cultivars, ‘Show Winner’ and ‘Pink Jumbo Banana’ (C. maxima) stood out as promising candidates for nutraceutical applications due to their elevated levels of tocopherols, carotenoids, and squalene. A moderate n-6/n-3 fatty acid ratio (100–170), coupled with balanced levels of γ-tocopherol and squalene, was found to significantly enhance the oxidative stability of pumpkin seed lipids. These lipid fractions also show potential as stabilizing additives for oils rich in α-linolenic acid but deficient in natural antioxidants. Full article

Grafting is widely used to improve the resistance to abiotic stresses in cucurbit plants, but the effect and molecular mechanism of grafting on cold stress are still unknown in melon. In this study, phenotypic characteristics, physiological indexes, small-RNA sequencing and expression analyses were performed on grafted plants with pumpkin rootstock (PG) and self-grafted plants (SG) to explore the mechanism of changed cold tolerance by grafting in melon. Compared with SG plants, the cold tolerance was obviously enhanced, the malondialdehyde (MDA) content was significantly decreased and the activities of antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD) were significantly increased in PG plants. Depend on differentially expressed miRNA (DEM) identification and expression pattern analyses, cme-miR156b, cme-miR156f and chr07_30026 were thought to play a key role in enhancing low-temperature resistance resulting from grafting. Subsequently, 24, 37 and 17 target genes of cme-miR156b, cme-miR156f and chr07_30026 were respectively predicted, and 21 target genes were co-regulated by cme-miR156b and cme-miR156f. Among these 57 unique target genes, the putative promoter of 13 target genes contained the low-temperature responsive (LTR) cis-acting element. The results of qRT-PCR indicated that six target genes (MELO3C002370, MELO3C009217, MELO3C018972, MELO3C016713, MELO3C012858 and MELO3C000732) displayed the opposite expression pattern to their corresponding miRNAs. Furthermore, MELO3C002370, MELO3C016713 and MELO3C012858 were significantly downregulated in cold-resistant cultivars and upregulated in cold-sensitive varieties after cold stimulus, and they acted as the key negative regulators of low-temperature response in melon. This study revealed three key miRNAs and three putative target genes involved in the cold tolerance of melon and provided a molecular basis underlying how grafting improved the low-temperature resistance of melon plants. Full article

Pumpkin (Cucurbita maxima) is an important vegetable crop of the Cucurbitaceae plant family. The fruits of pumpkin are often used as directly edible food or raw material for a number of processed foods. In nature, mature pumpkin fruits differ in size, shape, and color. The Atlantic Giant (AG) cultivar has the world’s largest fruits and is described as the giant pumpkin. AG is well-known for its large and bright-colored fruits with high ornamental and economic value. At present, there are insufficient studies that have focused on the formation factors of the AG cultivar. To address these knowledge gaps, we performed comparative transcriptome, proteome, and metabolome analysis of fruits from the AG cultivar and a pumpkin with relatively small fruit (Hubbard). The results indicate that up-regulation of gene-encoded expansins contributed to fruit cell expansion, and the increased presence of photoassimilates (stachyose and D-glucose) and jasmonic acid (JA) accumulation worked together in terms of the formation of large fruit in the AG cultivar. Notably, perhaps due to the rapid transport of photoassimilates, abundant stachyose that was not converted into glucose in time was detected in giant pumpkin fruits, implying that a unique mode of assimilate unloading is in existence in the AG cultivar. The potential molecular regulatory network of photoassimilate metabolism closely related to pumpkin fruit expansion was also investigated, finding that three MYB transcription factors, namely CmaCh02G015900, CmaCh01G018100, and CmaCh06G011110, may be involved in metabolic regulation. In addition, neoxanthin (a type of carotenoid) exhibited decreased accumulation that was attributed to the down-regulation of carotenoid biosynthesis genes in AG fruits, which may lead to pigmentation differences between the two pumpkin cultivars. Our current work will provide new insights into the potential formation factors of giant pumpkins for further systematic elucidation. Full article

The aim of this study was to evaluate the chemical profile of the flesh and yield parameters of Greek pumpkin genotypes, including nine local landraces and two commercially available cultivars, focusing on valorizing the genetic pool of Cucurbita sp. with high added value products. Yield parameters (mean fruit weight and total fruit yield) recorded high variability with genotypes V8 and V2 showing the highest fruit yield. Moreover, genotype V11 was the most abundant in glucose and total sugars and scored the highest sweetness index suggesting good taste and promising marketing attributes. The highest antioxidant activity (OxHLIA assay) was assessed in the V8 genotype, while the V2 genotype showed the highest α-, β- and total tocopherols content. Oxalic acid was the main organic acid, followed by malic and citric acids, while organic acid composition varied among the tested genotypes. Moreover, the flesh extracts showed varied antimicrobial activity against several bacteria and fungi, while no toxicity against non-tumor cells was recorded. In conclusion, our results make evident the presence of high innate variability in terms of crop performance, chemical composition and bioactive properties not only between the different genotypes but also at the intra-populational level. This finding is of high importance for the valorization of the local genetic pool of Cucurbita species through the selection of elite genotypes with high yield and quality of fruit, contributing to the conservation of valuable genetic material and limitation of the risk of genetic erosion due to neglect of local landraces. Full article

Pumpkin (Cucurbita moschata) undergoes several cooking processes before consumption, leading to alterations in both its physical attributes and chemical composition. Therefore, the objective of this work is to evaluate the effect of different cooking treatments (convection oven, steaming, microwaving, and boiling) on bioactive compounds and antioxidant activity in different pumpkin cultivars: Cuyano INTA, Dorado INTA, Paquito INTA, and Cokena INTA. The results showed high variability in the concentration of bioactive compounds and antioxidant activity between the cultivars (p < 0.001). The stability of bioactive compounds and antioxidant activity after cooking was found to be genotype × cooking treatment interaction dependent (p < 0.001). Nevertheless, the free radical scavenging activity exhibited by cooked pumpkins was found to be high, in the range of 69.93 to 256.44 µM Trolox g⁻¹ fw. Full article

Chile peppers (Capsicum annuum L.) are good sources of vitamins and minerals that can be included in the diet to mitigate nutritional deficiencies. Metabolomics examines the metabolites involved in biological pathways to understand the genes related to complex phenotypes such as the nutritional quality traits. The current study surveys the different metabolites present in jalapeño (‘NuMex Pumpkin Spice’) and serrano (‘NuMex LotaLutein’) type chile peppers grown in New Mexico using a widely targeted metabolomics approach, with the ‘NuMex LotaLutein’ as control. A total of 1088 different metabolites were detected, where 345 metabolites were differentially expressed; 203 (59%) were downregulated and 142 (41%) were upregulated (i.e., relative metabolite content is higher in ‘NuMex Pumpkin Spice’). The upregulated metabolites comprised mostly of phenolic acids (42), flavonoids (22), and organic acids (13). Analyses of principal component (PC) and orthogonal partial least squares demonstrated clustering based on cultivars, where at least 60% of variation was attributed to the first two PCs. Pathway annotation identified 89 metabolites which are involved in metabolic pathways and the biosynthesis of secondary metabolites. Altogether, metabolomics provided insights into the different metabolites present which can be targeted for breeding and selection towards the improvement of nutritional quality traits in Capsicum. Full article

The goal of this review is to provide an overview of the current findings on the major carotenoids and their content in pumpkin products and by-products. The content of total carotenoids and the composition of carotenoids in pumpkins depend mainly on the species and cultivar, pedoclimatic conditions, the part of the plant (pulp, peel or seed), extraction procedures and the type of solvent used for extraction. The major carotenoids identified in pumpkins were β-carotene, α-carotene, lutein and zeaxanthin. β-Carotene is the major carotenoid in most pumpkin species. The number and content of total carotenoids are higher when minor carotenoids and ester forms are considered. The use of carotenoids in the development of functional foods has been the topic of many versatile studies in recent years, as they add significant value to foods associated with numerous health benefits. In view of this, pumpkin and pumpkin by-products can serve as a valuable source of carotenoids. Full article

Cucurbits are important economic crops worldwide. However, the cucurbit leaf curl disease (CuLCD), caused by whitefly-transmitted begomoviruses constrains their production. In Southeast Asia, three major begomoviruses, Tomato leaf curl New Delhi virus (ToLCNDV), Squash leaf curl China virus (SLCCNV) and Squash leaf curl Philippines virus (SLCuPV) are associated with CuLCD. SLCuPV and SLCCNV were identified in Luzon, the Philippines. Here, the genetic diversity and geographic distribution of CuLCD-associated begomoviruses in the Philippines were studied based on 103 begomovirus detected out of 249 cucurbit samples collected from 60 locations throughout the country in 2018 and 2019. The presence of SLCCNV and SLCuPV throughout the Philippines were confirmed by begomovirus PCR detection and viral DNA sequence analysis. SLCuPV was determined as a predominant CuLCD-associated begomovirus and grouped into two strains. Interestingly, SLCCNV was detected in pumpkin and bottle gourd without associated viral DNA-B and mixed-infected with SLCuPV. Furthermore, the pathogenicity of selected isolates of SLCCNV and SLCuPV was confirmed. The results provide virus genetic diversity associated with CuLCD for further disease management, especially in developing the disease-resistant cultivars in the Philippines as well as Southeast Asia. Full article

Two different qualities of pumpkin, cultivars G1519 and G1511, were grown in the same environment under identical management. However, their qualities, such as the contents of total soluble solids, starch, protein, and vitamin C, were significantly different. Do rhizospheric microbes contribute to pumpkin quality? To answer this question, this study investigated the soil microbial compositions in the rhizospheres of different quality pumpkin cultivars to determine the differences in these soil microbial compositions and thus determine how soil microbes may affect pumpkin quality. Firstly, a randomized complete block design with two pumpkin cultivars and three replications was performed in this study. The soil microbial compositions and structures in the rhizospheres of the two pumpkin cultivars were analyzed using a high-throughput sequencing technique. In comparison with the low-quality pumpkin cultivar (G1519), higher microbial diversity and richness could be found in the rhizospheres of the high-quality pumpkin cultivar (G1511). The results showed that there were significant differences in the soil bacterial and fungal community compositions in the rhizospheres of the high- and low-quality pumpkin cultivars. Although the compositions and proportions of microorganisms were similar in the rhizospheres of the two pumpkin cultivars, the proportions of Basidiomycota and Micropsalliota in the G1519 rhizosphere were much higher than those in the G1511 rhizosphere. Furthermore, the fungal phylum and genus Rozellomycota and Unclassified_p__Rozellomycota were unique in the rhizosphere of the high-quality pumpkin cultivar (G1511). All the above results indicate that soil microbes were enriched differentially in the rhizospheres of the low- and high-quality pumpkin cultivars. In other words, more abundant soil microbes were recruited in the rhizosphere of the high-quality pumpkin cultivar as compared to that of the low-quality cultivar. Rozellomycota and Unclassified_p__Rozellomycota may be functional microorganisms relating to pumpkin quality. Full article

This study was conducted to investigate the influence of pumpkin cultivar as a fermented semi-product on the selected quality parameters of functional non-dairy frozen desserts, which were prepared using the potentially probiotic strain cultures L. rhamnosus Lock 0900 and L. casei O14. Microbiological status, pH, sugar and carotenoids content, antioxidant activity, color and sensory quality have been checked. Regardless of the pumpkin cultivar used, the lactic acid fermentation of pulps with selected bacterial strains decreased reducing sugar and total sugars content. Improvement in the antioxidant activity was also observed. The impact of the individual sensory attributes on the overall quality was determined. The overall quality of the investigated pumpkin sorbets was positively driven by the sweet taste, pumpkin flavor, smoothness of texture, and negatively driven by acidic flavor, pungent taste, and bitter taste, verified by PCA method. All of the final products achieved high survival of probiotics (higher than 8.4 log CFU/g) and revealed a good sensory quality (overall quality higher than 8 c.u). The treatments with the cultivar “Melon Yellow” of the Cucurbita maxima species, were characterized by significantly higher (p < 0.05) carotenoids content, total sugars and reducing sugars content and antioxidant activity, measured by two methods. It can be concluded that the pumpkin cultivar and strain culture used for the fermentation affect the count of potentially probiotic bacteria in the final products, the composition of bioactive compounds, antioxidant activity and sensory quality of the functional pumpkin frozen desserts. Full article

Pumpkin (Cucurbita moschata Duchesne ex Poir.) is a multipurpose cash crop rich in antioxidants, minerals, and vitamins; the seeds are also a good source of quality oils. However, pumpkin is susceptible to the fungus Podosphaera xanthii, an obligate biotrophic pathogen, which usually causes powdery mildew (PM) on both sides of the leaves and reduces photosynthesis. The fruits of infected plants are often smaller than usual and unpalatable. This study identified a novel gene that involves PM resistance in pumpkins through a genome-wide association study (GWAS). The allelic variation identified in the CmoCh3G009850 gene encoding for AP2-like ethylene-responsive transcription factor (CmoAP2/ERF) was proven to be involved in PM resistance. Validation of the GWAS data revealed six single nucleotide polymorphism (SNP) variations in the CmoAP2/ERF coding sequence between the resistant (IT 274039 [PMR]) and the susceptible (IT 278592 [PMS]). A polymorphic marker (dCAPS) was developed based on the allelic diversity to differentiate these two haplotypes. Genetic analysis in the segregating population derived from PMS and PMR parents provided evidence for an incomplete dominant gene-mediated PM resistance. Further, the qRT-PCR assay validated the elevated expression of CmoAP2/ERF during PM infection in the PMR compared with PMS. These results highlighted the pivotal role of CmoAP2/ERF in conferring resistance to PM and identifies it as a valuable molecular entity for breeding resistant pumpkin cultivars. Full article

Pumpkin (Cucurbita pepo) seeds are nutritious and valued as a source of vegetable oil, protein, healthy fatty acids, and minerals. Pumpkin seeds that are naturally devoid of the seedcoat (hull-less) are preferred by the industry as they eliminate the need for de-hulling prior to use. A single recessive gene, designated as n or h, controls the hull-less seed trait in pumpkin. Visual selection for the trait is easy, however, it is resource intensive when applied to large breeding populations. High throughput genotyping assays can aid in the identification of suitable individuals in segregating populations through marker-assisted selection. In the current study, the QTL-seq approach was used to identify genetic loci, SNP markers and candidate genes associated with the hull-less trait in a segregating F₂ population (n = 143) derived from a cross between Kakai (hull-less) × Table Gold Acorn (hulled). The segregation of the hull-less trait in the F₂ population fit a 3:1 ratio (p < 0.05). QTL-seq analysis detected a single QTL on chromosome 12 (Qtlhull-less-C12) which was significantly associated with the hull-less trait in C. pepo. Twenty-eight SNPs were genotyped in the population, two among which (Ch12_3412046 and Ch12_3417142) were significantly associated (p < 0.05) with the hull-less trait in cultivars and accessions of diverse genetic background. Several candidate genes fall within the Qtlhull-less-C12 interval, among them is the No Apical meristem (NAC) domain-containing protein and a Fiber Protein fb11 gene involved in lignin accumulation and cell wall deposition across plant species, respectively. The findings of this study will facilitate the marker-assisted selection for the hull-less seed trait in pumpkin and further our understanding of the functional mechanisms underlying the trait across cucurbit crops. Full article

Powdery mildew is one of the severe diseases on common bean in Southwestern China, but the identity of the pathogen inciting this disease is unclear. The objective of this study was to identify the causal agent of common bean powdery mildew and to screen resistant cultivars. The pathogen was identified through morphological identification, molecular phylogenetic analysis, and pathogenicity tests. Resistance of common bean cultivars was evaluated by artificial inoculation at the seedling stage. The common bean powdery mildew isolate CBPM1 was obtained after pathogen isolation and purification. Morphological identification confirmed that the isolate CBPM1 belonged to the Oidium subgenus Pseudoidium and germinated Pseudoidium-type germ tubes. Molecular phylogenetic analysis showed that the isolate CBPM1 and Erysiphe vignae isolates from different hosts were clustered into a distinct group. The pathogenicity and host range tests revealed that the isolate CBPM1 was strongly pathogenic to common bean, multiflora bean, lablab bean, cowpea, and mung bean, but not to soybean, adzuki bean, pea, faba bean, chickpea, lentil, pumpkin, and cucumber. In addition, 54 common bean cultivars were identified for resistance to powdery mildew, and 15 were resistant or segregant. Based on the morphological, molecular and pathogenic characteristics, the causal agent of common bean powdery mildew was identified as E. vignae. This is the first time E. vignae has been confirmed on common bean. Cultivars with different resistance levels were screened, and these cultivars could be used for disease control or the breeding of new resistant cultivars. Full article

Sweet potatoes have multiple uses as food, feed, and in industrial production. They are characterized by their need for high temperatures for optimal development. This study aimed to analyze the quantitative and qualitative aspects of growing sweet potato cultivars in southwest Romania using mulching and non-mulching systems. The effects of mulching on the production of tuberous roots and the contents of total soluble substance, vitamin C, starch, total polyphenols, and antioxidant activity (DPPH) were evaluated in three cultivars with white pulp (the ‘Pumpkin’ and ‘Chestnut’ cultivars) and with orange pulp (the ‘Italian’ cultivar). It was found that mulching with polyethylene film improved the production of sweet potatoes, amounting to 41.42 t/ha in the case of the ‘Italian’ cultivar. Moreover, the effect of mulch induced increases in total soluble substance (16.40%) and starch (16.01%) in the ‘Chestnut’ cultivar, in vitamin C (9.23 mg/100 g d.w.) in the ‘Pumpkin’ cultivar, and in antioxidant activity in the ‘Pumpkin’ (2716.55 µmol AsA/g d.w.) and ‘Chestnut’ cultivars (1131.31 µmol AsA/g d.w.), while the polyphenols in the ‘Italian’ cultivar decreased. Full article