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Copyright of International Journal of New Chemistry is the property of International Journal of New Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cucurbits are a diverse group of plant species grown worldwide for both immature and mature fruits. The fruit is the finest source of betacarotene, vitamins, and minerals. The crop originated in South America, with Mexico having the most diversity, but it is now scattered worldwide, with Asia Minor serving as a secondary center of diversity. Cucurbita pepo and C. moschata are the two most extensively cultivated species, demonstrating tolerance to a wide range of environments. The systematic breeding process has resulted in the production of numerous significant cultivars appropriate for a variety of applications. The spontaneous mutation resulted in hull-less seeded cultivars, which allowed for the use of seeds for culinary purposes. Bush growth habit, hull-less seeded, higher beta-carotene, biotic stresses such as fungal (powdery mildew, downy mildew, root or crown rot) and viral (begomovirus and potyviruses) diseases were the primary focus of the breeding. C. okeechobeensis and C. lundelliana are wild species with the capacity to withstand a variety of diseases. The genomic sequences for the species C. moschata, C. maxima, C. pepo subsp. pepo, C. argyrosperma subsp. argyrosperma, and C. argyrosperma subsp. sororia is available for use in precision breeding. Saturated genetic maps and the identification of QTLs related to horticulturally important traits will aid in the use of genomic resources for quick improvement and cultivar development with biotic and abiotic stress tolerance. [ABSTRACT FROM AUTHOR]

Copyright of Scientific Journal of Agricultural Sciences (SJAS) is the property of Beni Suef University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study was carried out to determine stage progression and specific plant and fruit characteristics in purposefully created summer squash genotypes. In this study, which was carried out in 2019, 59 squash genotypes were assessed with 24 morphological measurements and observations involving plant and fruit characteristics, and one-generation advancement was achieved. Cluster and PCA were implemented to determine the relationship between genotypes determined at the end of single plant selection. A dendrogram was constructed to assess the morphological similarities between the genotypes. In this respect, four main groups and 12 subgroups were determined in the cluster analysis performed among squash genotypes based on 24 morphological variables, while the 10 PC axis explained 94.3% of the total variation in the PCA. When the variance values of the principal component axis were examined, it was seen that the first principal component axis explained 28.8% of the total variation, the second principal component axis explained 26% of the variation, and the third principal component axis explained 11.2% of the total variation. Principal component analyses revealed that (i) 66% of the qualitative (neck in unripe fruit, curving of the neck in unripe fruit, mottling in unripe fruit, and type of mottling in unripe fruit) variation was explained by the first three components. At the end of the study, the phenotypic diversity that exists in this core collection provides valuable information to improve agronomic traits in the summer squash breeding program. [ABSTRACT FROM AUTHOR]

Drought is an increasingly important consequence of climate change. Drought often causes plants to alter patterns of resource allocation, which in turn can affect how plants interact with other species. How these altered interactions subsequently influence plant reproductive success remains incompletely understood and may depend on the degree of specialization exhibited by antagonists and mutualists. Specialist pollinators, for example, are dependent on floral resources from their obligate hosts and under drought conditions may thus indiscriminately visit these hosts (at least in certain circumstances). Generalist pollinators, in contrast, may only forage on host plants in good condition, given that they can forage on other plant species. We tested this hypothesis and its consequences for plant reproduction in squash (Cucurbita pepo) grown along an experimental moisture gradient ranging from dry (growth and flowering compromised) to wet conditions. Floral visitation increased with plant soil moisture for generalist honey bees but was independent of plant soil moisture for specialist squash bees. Pollen production increased with plant soil moisture, and fluorescent pigments placed on flowers revealed that pollinators primarily moved pollen from male flowers on well‐watered plants to the stigmas of female flowers on well‐watered plants. Seed set increased with increasing plant soil moisture but, notably, was higher in bee‐pollinated plants compared to plants pollinated by hand with an even mix of pollen from plants grown at either end of the experimental moisture gradient. These results suggest that superior pollen rewards, perhaps combined with selective foraging by generalists, enhanced reproductive success in C. pepo when plant soil moisture was high and more generally illustrate that pollinator behavior may contribute to how drought conditions affect plant reproduction. [ABSTRACT FROM AUTHOR]

The use of bio-stimulants (BSs) has become an important policy in managing many stressed crop plants through the regulation of the balance of phytohormones, osmo-protectors (OPs), antioxidant systems, and gene expression, all of which reflect plant growth and productivity. Garlic + onion extract (GOE) at a concentration of 2.0–3.0% and diluted bee honey solution (BHs) at a concentration of 1.0–1.5% were applied exogenously to squash (Cucurbita pepo) plants subjected to cadmium (Cd) + lead (Pb) stress (0.3 mM CdCl2 + 0.3 mM PbCl2). The objective was to determine the effects of these treatments on growth characteristics, organic metabolites/biomolecules, and mineral nutrients. Cd + Pb stress significantly increased electrolyte leakage (EL, 103%) and malondialdehyde (MDA, 90%) because of an increase in hydrogen peroxide (H2O2, 145%) and superoxide (O2•−, 152%) levels, and contents of abscisic acid (ABA, 164%), Cd (674–711%), and Pb (754–805%). Consequently, marked increases in the contents of OPs and non-enzymatic antioxidants (28–133%), activities of antioxidant enzymes (48–80%), and expressions of enzyme genes (60–84%) were observed. The administration of Cd + Pb treatment reduced plant growth and development parameters (25–59%), yield components (61–86%), photosynthetic components (27–67%), leaf proportional water content (26%), indole-3-acetic acid (IAA, 44%), gibberellic acid (GA3, 56%), and cyto-kinin (CKs, 49%) contents. Nonetheless, the administration of GOE, BHs, and GOE + BHs attenuated the adverse impacts of Cd + Pb stress. The best treatment was GOE + BHs which significantly decreased EL (52%) and MDA (49%) because of a reduction of O2•– (61%), H2O2 (60%), ABA (63%), Cd (89–91%), and Pb (89–91%) levels. This positive outcome was linked to an increase in the OPs' (22–46%) and non-enzymatic antioxidant (27–46%) levels, activities of enzymes (26–44%), and enzyme gene expressions (35–40%), all of which contributed to the promoted relative water content (RWC, 37%), pigment contents (47–194%), hormonal levels (82–132%), growth traits (31–149%), yield components (154–626%), and fruit quality traits (31–92%). From these results, it can be concluded that treatment of GOE + BHs is recommended as a foliar application to reduce the adverse effects of Cd + Pb stress treatment in squash. [ABSTRACT FROM AUTHOR]

Pumpkin, a member of the Cucurbitaceae plant family is an underutilized crop in Nigeria. This plant requires minimal agronomic input to produce optimal yield and it is drought tolerant. However, due to preservation, the fruit does not remain biochemically the same. What happens to squash stored for months after harvesting at room temperature needs to be examined from nutritional point of view. Therefore, this study was performed to evaluate the effects of storage at ambient temperature and relative humidity on selected vitamins (A, C, and E), and the proximate (crude protein, crude fiber, crude ash, and carbohydrate) in the green and orange morphotypes of pumpkin fruit. Pumpkins harvested in 2015 were stored for 4 months (January to April) and nutritional parameters evaluated monthly using standard assays. The results showed that the vitamin A content did not change significantly (P<0.05) over the storage period and morphotypes while the vitamin C and vitamin E contents decreased by 15% and 18%, respectively, when comparing the 1st and 4th months of storage. Crude protein and fat content decreased significantly over the storage period. However, crude fiber and ash increased in storage time. Except for crude fiber, the two morphotypes behaved similarly over the storage period. Remarkably, vitamin A concentrations in squash did not change after harvest, and some of the nutrients studied were not significantly affected during the first 4 months of storage. This information is especially important for people in rural areas limited in modern ways of storing fruit vegetable after harvest. [ABSTRACT FROM AUTHOR]

Copyright of Hortscience Journal of Suez Canal University is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The current study focuses on the effects of Cucumber mosaic virus (CMV) infection on phytochemical changes and pathogenesis- and phenylpropanoid pathway-associated gene activities in squash (Cucurbita pepo L.) plants during a time course of 2 to 12 days post inoculation (dpi). The identity of the CMV isolate was confirmed by DAS-ELISA, TEM, and coat protein gene sequence. The CMV infection initially boosts and then suppresses transcript levels of the defense-related genes PR-1, PR-2, PAL, HQT, and CHS during the investigated time course compared to controls. The expression profile during the time-course study indicated that early, transient induction of PR-1 occurs during CMV infection, while CMV induced the expression of PR-2 in systemically infected squash tissues at all time points and suppressed the expression of PAL and HQT at 8-12 dpi. CHS transcript levels fluctuated between up- and down-regulation, but by 12 dpi, CHS expression reached its peak. The HPLC and GC–MS analyses of CMV-infected squash extracts revealed that different phenolic, flavonoid, and fatty acid compounds could be induced or suppressed upon CMV infection. In particular, CMV could suppress the synthesis of most phenolic compounds, specifically chlorogenic acid, possibly leading to the virus's rapid spread. [ABSTRACT FROM AUTHOR]

Field research experiments were conducted during the two successive growing seasons of 2019/2020 and 2020 in the Experimental Farm, Faculty of Agriculture, Menoufia University to evaluate changes in growth, nutritional contents and yield of squash (Cucurbita pepo L.) under the foliar application of four biostimulant treatments i.e., aqueous moringa leaf extract at 1:30 v/v (MLE) and potent microorganisms at 20 mL L-1 (EM1) as natural growth regulators each alone or tougher or in combinations with N at rates of 0, 75 and 100% of the recommended nitrogen fertilization rate. This research was coordinated in a Split plot design in three replications. The results showed that the addition of nitrogen at 100% led to a maximum significant increase in the growth chrematistics, that is, the number of leaves and the fresh and dry weight of leaves compared to the unfertilized control. The chlorophyll contents increase significantly with increasing N supply up to 75% with moringa leaf extract foliar application. The highest N, P and K contents were found in squash leaves treated with N at 100% of the recommended rate. The yield and its components of squash plants increased significantly with the increased of nitrogen supply up to 100% of the recommended rate. Combined application of EM1 and MLE resulted in a significant increase in growth traits and fruit yield compared to the control treatment. [ABSTRACT FROM AUTHOR]

Introduction: The species and functional diversity of pollinators are important components for the reproduction of cultivated plants. More information is necessary about this diversity and its geographical variation in crops such as Cucurbita pepo, an important crop in global agriculture. Objective: To describe the taxonomic diversity, geographic variation and foraging patterns of the community of bees that visit C. pepo crops in Costa Rica. Methods: Squash fields were visited at 11 locations within three geographic regions of the country, where the groups of bees and their relative frequency were determined. Through video recordings, information was obtained on their behavior at two locations. Results: A minimum of 27 species belonging to 19 genera and 2 families of bees were found. Three species were dominant in 10 localities (Eucera limitaris, Apis mellifera and Trigona corvina). Altitude reduces bee diversity due to the dominance of Bombus ephipiatus in high regions. Two genera of halictids (Megalopta and Caenaugochlora) that are rarely reported in this crop were frequently observed. Trigona bees dominated among the flowers later in the morning, lacerating nectary holes to facilitate nectar collection. Conclusions: Squash fields in Costa Rica are visited by a highly diverse bee community, which may ensure pollination via complementarity in the face of spatial or seasonal changes in environmental conditions. [ABSTRACT FROM AUTHOR]

Key message: Two QTL mapping approaches were used to identify a total of six QTL associated with Phytophthora root and crown rot resistance in a biparental squash population. Phytophthora root and crown rot, caused by the soilborne oomycete pathogen Phytophthora capsici, leads to severe yield losses in squash (Cucurbita pepo). To identify quantitative trait loci (QTL) involved in resistance to this disease, we crossed a partially resistant squash breeding line with a susceptible zucchini cultivar and evaluated over 13,000 F2 seedlings in a greenhouse screen. Bulked segregant analysis with whole genome resequencing (BSA-Seq) resulted in the identification of five genomic regions—on chromosomes 4, 5, 8, 12, and 16—featuring significant allele frequency differentiation between susceptible and resistant bulks in each of two independent replicates. In addition, we conducted linkage mapping using a population of 176 F3 families derived from individually genotyped F2 individuals. Variation in disease severity among these families was best explained by a four-QTL model, comprising the same loci identified via BSA-Seq on chromosomes 4, 5, and 8 as well as an additional locus on chromosome 19, for a combined total of six QTL identified between both methods. Loci, whether those identified by BSA-Seq or linkage mapping, were of small-to-moderate effect, collectively accounting for 28–35% and individually for 2–10% of the phenotypic variance explained. However, a multiple linear regression model using one marker in each BSA-Seq QTL could predict F2:3 disease severity with only a slight drop in cross-validation accuracy compared to genomic prediction models using genome-wide markers. These results suggest that marker-assisted selection could be a suitable approach for improving Phytophthora crown and root rot resistance in squash. [ABSTRACT FROM AUTHOR]

This study aimed to get the most possible benefit of using deficit irrigation to maximize water productivity of squash, besides investigating the ability of drip irrigation uniformity to reduce the expected negative effect of deficit irrigation on squash crop yield production (Cucurbita pepo - Hybrid Revera). Three levels of irrigation uniformity (UL) based on the value of uniformity coefficient (UC) namely excellent (E), very good (VG), and unacceptable (UA) were examined with three irrigation levels (IL) based on crop evapotranspiration (ETc) which were full irrigation (FI) or 100% ETc; in addition to two deficit irrigation levels 90% ETc (DI90), and 80% ETc (DI80). Results showed that both ULs and ILs had significant effect on squash production. There was significant reduction in crop yield values due to the decrease in irrigation water at all uniformity levels. The greatest values of water productivity (WP) for all ULs were obtained at FI followed by DI80 and the least was DI90. The profits of water volume unit showed that the greatest values were for E level. FI recorded the greatest profits under all ULs. Increasing uniformity level led to increase crop production but it could not prevent the significant reduction in squash crop related to deficit irrigation. The study recommended to manage drip irrigation uniformity and irrigation water separately as the high levels of uniformity could not prevent the effect of water shortage regarding the decrease of crop yield, WP, and water unit profits. Keywords: Deficit irrigation, Drip irrigation, Production, Squash, Uniformity. [ABSTRACT FROM AUTHOR]

Crop domestication and improvement often concurrently affect plant resistance to pests and production of secondary metabolites, creating challenges for isolating the ecological implications of selection for specific metabolites. Cucurbitacins are bitter triterpenoids with extreme phenotypic differences between Cucurbitaceae lineages, yet we lack integrated models of herbivore preference, cucurbitacin accumulation, and underlying genetic mechanisms. In Cucurbita pepo, we dissected the effect of cotyledon cucurbitacins on preference of a specialist insect pest (Acalymma vittatum) for multiple tissues, assessed genetic loci underlying cucurbitacin accumulation in diverse germplasm and a biparental F2 population (from a cross between two independent domesticates), and characterized quantitative associations between gene expression and metabolites during seedling development. Acalymma vittatum affinity for cotyledons is mediated by cucurbitacins, but other traits contribute to whole‐plant resistance. Cotyledon cucurbitacin accumulation was associated with population structure, and our genetic mapping identified a single locus, Bi‐4, containing genes relevant to transport and regulation – not biosynthesis – that diverged between lineages. These candidate genes were expressed during seedling development, most prominently a putative secondary metabolite transporter. Taken together, these findings support the testable hypothesis that breeding for plant resistance to insects involves targeting genes for regulation and transport of defensive metabolites, in addition to core biosynthesis genes. In domesticated Cucurbita pepo we found a novel genetic locus underlying spatial and temporal variation in cucurbitacin production, defensive metabolites that confer susceptibility to a specialized, cucurbitacin‐sequestering insect pest, Acalymma vittatum (Coleoptera: Chrysomelidae) [ABSTRACT FROM AUTHOR]

Summary: Ethylene is the key regulator of sex determination in monoecious species of the family Cucurbitaceae. This hormone determines which individual floral meristems develop as female or male flowers and the female flowering transition. The sex determination genes discovered so far code for ethylene biosynthesis enzymes, but little is known about the importance of ethylene signaling components. In this paper we characterize two novel ethylene‐insensitive mutations (etr1a‐1 and etr1b) which block the female flowering transition of Cucurbita pepo; this makes plants produce male flowers indefinitely (androecy). Two missense mutations in the ethylene‐binding domain of the ethylene receptors CpETR1A or CpETR1B were identified as the causal mutations of these phenotypes by using whole‐genome resequencing. The distinctive phenotypes of single and double mutants for four etr mutations have demonstrated that the final level of ethylene insensitivity depends upon the strength and dosage of mutant alleles for at least three cooperating ETR genes, and that the level of ethylene insensitivity determines the final sex phenotype of the plant. The sex phenotype ranges from monoecy in ethylene‐sensitive wild‐type plants to androecy in the strongest ethylene‐insensitive ones, via andromonoecy in partially ethylene‐insensitive plants. The induction of female flowering transition was found to be associated with upregulation of CpACS11, CpACO2 and CpACS27, three ethylene biosynthesis genes required for female flower development. A model is proposed herein, integrating both ethylene biosynthesis and receptor genes into the genetic network which regulates sex determination in C. pepo. Significance Statement: Ethylene receptors not only regulate the fate of the floral meristem towards a female, hermaphrodite or male flower but are also involved in the female flowering transition. In fact, two mutations in ethylene receptors completely block this transition and result in plants that produce only male flowers (androecy). The interaction between different ethylene receptors, as well as other ethylene biosynthesis genes, has been studied to propose a model for sex determination in Cucurbita pepo. [ABSTRACT FROM AUTHOR]

Successful management of insect crop pests requires an understanding of the cues and spatial scales at which they function to affect rates of attack of preferred and non‐preferred host plants. A long‐standing conceptual framework in insect–plant ecology posits that there is hierarchical structure spanning host location, acceptance and attack that could be exploited for integrated pest management.We investigated how plant‐ and insect‐derived chemical cues affect successive decisions of host choice in aggregating insects, and tested predictions in the Cucurbita pepo–Acalymma vittatum system. Acalymma vittatum is an aggregating specialist beetle pest that strongly prefers zucchini (C. p. pepo) to summer squash (C. p. ovifera), two independent domesticates of C. pepo. We hypothesized that subspecies‐specific plant traits, especially volatile cues, interact with the male‐produced aggregation pheromone to amplify beetle preference for C. p. pepo.Differential beetle attack of C. pepo subspecies in the field is not determined by plant traits that affect host finding or differential aggregation due to pheromones: across two years, beetles had strong density‐dependent attraction to both subspecies when male beetles were feeding, and no interactions between plant volatiles and the male‐produced pheromone were detected. In the absence of male pheromone emission, beetles were equally unattracted to plants with or without beetle feeding.In contrast, plant traits that mediate insect acceptance appear to underlie differences in preference. At a local scale, beetles did not accept and emigrated from C. p. ovifera compared to C. p. pepo. Distinct volatile emissions were observed between subspecies, but further work is needed to identify if these volatiles promote emigration.Synthesis and applications. By dissecting pest preference during successive host choice decisions, we isolated a trait with implications for pest management. Beetles on cucurbits can be managed by employing cultivars with differential susceptibility (e.g. trap cropping), and the mechanistic knowledge presented here informs best practices and limitations for on‐farm applications. More broadly, pest management in diversified cropping systems can be enhanced through understanding how plant preference gradients affect herbivore movement and behaviour, and plant breeders can target traits to reduce herbivory in such systems. [ABSTRACT FROM AUTHOR]

Phytophtora capsici causes major diseases in cucurbit crops worldwide. In this study, we inoculated this pathogen into Cucurbita pepo subsp. pepo susceptible MUCU-16 and C. moschata tolerant M63. The gene expression of plant pathogenesis-related proteins chitinase (CpChiIV), lignin-forming peroxidase (CpLPOX), and defensin (CpDEF) and hormone-related enzymes salicylic acid (CpPAL) and ethylene (CpACO) was analyzed for two weeks post-inoculation in root and crown tissues. Differentially expressed genes were found between genotypes, tissues, days post-inoculation, and inoculated/non-inoculated samples. After inoculation, CpPAL and CpChiIV (crown) were downregulated in MUCU-16, while CpLPOX and CpDEF were upregulated in M63. In inoculated samples, higher expression changes were presented on days 10–14 than on day 3 for CpACO, CpLPOX, and CpDEF genes. Overexpression was higher for CpDEF compared to the other tested genes, indicating good suitability as a marker of biotic stress. The overexpression of CpDEF was higher in crown than in roots for both inoculated genotypes. The basal expression of CpPAL and CpDEF was higher in MUCU-16, but after inoculation, CpPAL and CpDEF gene expression were higher in M63. These changes suggest an association between CpDEF upregulation and tolerance, and between CpPAL downregulation and susceptibility.

Squash (Cucurbita pepo L.), is one of the most important vegetable crops for human nutriment in Egypt and the world. One of the most serious diseases that infect squash and cause yield losses was powdery mildew, caused by Podosphaera xanthisii. The aim of this study was to investigate the role of Bacillus subtilis, Paenibacillus polymyxa (109 cell ml/1), Trichoderma harzianum, T. album, T. viride and T. hamatum (107 spore ml/l) for controlling disease under greenhouse conditions. Results indicated that all treatments significantly inhibited the conidial germination of P. xanthii than control in vitro and decreased the incidence and disease severity after spraying with the bio-agents on squash plants under greenhouse conditions. The fungicide, Topas-100 (10.0% penconazole "w/v" [(R,S-1-(2-(2,4-dichlorophenyl)-Q pentyl)-1H-1,2,4-triazole]), followed by B. subtilis was highly significant for decreasing disease incidence (2.8 and 5.3%, respectively) and disease severity percentage (3.5 and 4.8%, respectively) than the control. The activities of biochemical changes, i.e., peroxidase, polyphenol oxidase, and total phenols, were significantly upregulated as results of most treatments. Also, bio-agent treatments caused significant increase in yield characteristics of squash plants such as fruit number/plant and fruit weight/plant than control. B. subtilis recorded the highest increase (110.9% and 98.7%) in fruit number and fruit weight/plant than control. [ABSTRACT FROM AUTHOR]

The present research was undertaken with the aim of justifying the effect of morphological, physiological, and nutritional properties in organically produced zucchini squash. The experiment consisted of two factors: three levels of pruning (P0 = no pruning, P1 = primary pruning at 20 days after transplanting (DAT), and P2 = secondary pruning at 30DAT) and four levels of vermicompost application (V0 = control, V1= 5t/ha, V2= 10t/ha, and V3 = 15 t/ha). The results demonstrated that morphological parameters, reproductive components, and yield and proximate compositions were significant differences among the treatments. Increased male and female flower production were recorded from primary pruning with 10 t/ha vermicompost treatment plots compared with control treatments. Finally, increased fruit number, individual fruit weight, fruit length, fruit diameter, total yield, carbohydrate, protein, crude fat, fiber, and ash were reported from the same treatment combination (P1V2). Taken together, 10 t/ha vermicompost with primary pruning appear to provide maximumoutput in terms of yield and nutrient value compared with other treatments. [ABSTRACT FROM AUTHOR]

Cucurbitaceae species depend on pollination by bees for fruit production. The objective of this present work was to identify the insect visitors of squash and to study the foraging behavior of the most abundant species in the field. Identification of foraging insects of Cucurbita pepo L. (Cucurbitaceae) were performed during 2016 and 2017 flowering periods in the region of Tizi- Ouzou (Algeria). Observations showed that the majority of the insects visiting squash flowers were Apoides Hymenoptera belonging to two families: Apidae and Halictidae. Six species of bees were recorded upon the plant, of which the honey bee Apis mellifera L. was the most frequent species. The study of the foraging activity of these insects showed that their visits to squash flowers were more intense at 8am and 9am and were essentially devoted to nectar harvesting. Bee visits proportions were higher on staminate flowers than on pistillate flowers. The duration of visits to flowers was significantly longer in staminate flowers. [ABSTRACT FROM AUTHOR]

Background: Clinically, diabetes is an important risk factor or a range of diseases including nephropathy,retinopathy, angiopathy and deficiency and it is increasing in prevalence according to some estimates. (Cucurbita pepo L.) from the cucurbitaceae family has a low calorie but high nutritional and medical value. The aim of this study was to observe the effect of cucurbita extract on serum factors of STZ induced diabetic rats including glucose level AGEs, lipid profile (cholesterol, HDL, LDL, and TG) and CRP. Material and methods: Diabetes type1 was induced to Male albino- wistar rats by STZ at a dosage of 50 mg kg-1. 17 rat were divided into three groups randomly including diabetic treated with extract, diabetic control and normal group. Diabetic group were force fed orally by cucurbita extract. The animals were anesthetized with ether at the end of 30 days and the blood was collected by syringe from their hearts for estimation of plasma glucose, TG, HDL, LDL, total cholesterol, CRP and AGEs Results: After measuring the serum factors and compares the result of the three groups to each other meaningful difference that shows the positive effect of cucurbita extract has been seen. Conclusion: According to the results we suggest that squash extract could have positive effect on regulating some of blood elements like glucose which are under the bad effect of diabetes type1 in rats. But more investigations are needed in this field to demonstrate the real benefits of cucurbita in curing diabetes and its related signs. [ABSTRACT FROM AUTHOR]

The species Cucurbita pepo includes several types of squashes; in Slovak Republic, well-known and oftenly grown squash types are patisson, zucchini, spaghetti squash, oil pumpkin etc. Several interesting squash types of Cucurbita pepo are grown abroad, including Acorn squash which is well-known mainly in USA. The aim of this study was to evaluate the important quantitative (yield per hectare, average fruit weight) and qualitative (total carotenoids, ascorbic acid, antioxidant activity, total soluble solids) yield parameters of Acorn squash fruits in comparison with patisson which is typical squash type of Cucurbita pepo in Slovak Republic. The field trial was realised in Košice-Šaca in 2016. Within experiment, four cultivars of Acorn type pumpkin were tested (Thelma Sanders; Jet Set; Table Gold; Cream of The Crop). The patisson 'Orfeus' was used as a comparative cultivar for evaluation of individual parameters of Acorn type pumpkin cultivars. Matured pumpkin fruits were harvested on the 7th September 2016. From aspect of yield quantity, Acorn cultivars are appeared as very interesting squash type with good yield potential for growing. The highest yield of squash fruits was found in the cultivar 'Cream of The Crop' (17.8 t.ha-1). In mentioned Acorn cultivar, the yield was higher about 87.4% compared to the tested patisson cultivar 'Orfeus' (9.5 t.ha-1). On the contrary, the average weight of squash fruits was reached in patisson cultivar 'Orfeus' (780.7 g). The qualitative parameters of fruits were expressively influenced by squash cultivar. The content of total carotenoids, ascorbic acid and total soluble solids was markedly higher in all Acorn cultivars, compared to the patisson cultivar 'Orfeus'. The highest content of total carotenoids (26.74 mg.kg-1 fresh weight) and ascorbic acid (238.79 mg.kg-1 f. w.) was found in the squash cultivar 'Table Gold'. The highest content of total soluble solids was determined in the cultivar 'Jet Set' (3.8 °Brix). On the contrary, the highest antioxidant activity (DPPH) was found in the patisson cultivar 'Orfeus' (10.80 %). On the basis of obtained results, it is possible to state that Acorn cultivars are very interesting squash type with promising yield potential for possible growing in conditions of Slovak Republic. In addition, Acorn squashes were expressed by higher content of several nutritional parameters compared to the typical squash type - patisson. Thus, these squashes could be an interesting vegetable for human nutrition. [ABSTRACT FROM AUTHOR]

Cucurbit crops are economically important worldwide. One of the most serious threats to cucurbit production is Zucchini yellow mosaic virus (ZYMV). Several resistant accessions were identified in Cucurbita moschata and their resistance was introgressed into Cucurbita pepo. However, the mode of inheritance of ZYMV resistance in C. pepo presents a great challenge to attempts at introgressing resistance into elite germplasm. The main goal of this work was to analyze the inheritance of ZYMV resistance and to identify markers associated with genes conferring resistance. An Illumina GoldenGate assay allowed us to assess polymorphism among nine squash genotypes and to discover six polymorphic single-nucleotide polymorphisms (SNPs) between two near-isogenic lines, 'True French' (susceptible to ZYMV) and Accession 381e (resistant to ZYMV). Two F and three BC populations obtained from crossing the ZYMV-resistant Accession 381e with two susceptible ones, the zucchini True French and the cocozelle 'San Pasquale,' were assayed for ZYMV resistance. Molecular analysis revealed an approximately 90% association between SNP1 and resistance, which was confirmed using High Resolution Melt (HRM) and a CAPS marker. Co-segregation up to 72% in populations segregating for resistance was observed for two other SNP markers that could be potentially linked to genes involved in resistance expression. A functional prediction of proteins involved in the resistance response was performed on genome scaffolds containing the three SNPs of interest. Indeed, 16 full-length pathogen recognition genes (PRGs) were identified around the three SNP markers. In particular, we discovered that two nucleotide-binding site leucine-rich repeat (NBS-LRR) protein-encoding genes were located near the SNP1 marker. The investigation of ZYMV resistance in squash populations and the genomic analysis performed in this work could be useful for better directing the introgression of disease resistance into elite C. pepo germplasm. [ABSTRACT FROM AUTHOR]

Zucchini squash ( Cucurbita pepo L.) plants were grown in a closed-loop hydroponic system and supplied with nutrient solution (NS) containing NaCl at different concentrations (0.7, 3, 5, and 7 mM). The primary aim of the study was to define the relationship between the concentration of Na+ and Cl− in the root zone solution and the respective Na+/water or Cl−/water uptake ratios (uptake concentrations, UC). A second objective was to determine the UC of macronutrients ( i.e., N, P, K, Ca, and Mg) and to test whether they are influenced by the gradual increase of the root zone salinity due to progressive NaCl accumulation. Two experiments were conducted, of which one (spring crop) was used to parameterize an existing empirical model, while the second one (autumn-winter crop) was commissioned to test the validity of the determined model parameters. Both Cl− and Na+ ions accumulated progressively in the root zone solution over time, showing a tendency to stabilize at final concentrations according to the corresponding NaCl treatment. The relationship between the Na+ and Cl− concentrations in the root zone and the Na+/water or Cl−/water uptake ratios was exponential and the model parameters successfully fitted to data from crops cultivated in different growth seasons. This model may be used to monitor Na+ and Cl− concentrations in the root environment of zucchini crops as relationships of the plant water consumption. The exposure of plants to NaCl affected the UC of N, K, Ca, and Mg, but the results for some nutrients were not consistent in both growth seasons. The measurements of plant growth characteristics ( i.e., biomass, yield, fruit quality, and photosynthesis) revealed that water resources containing up to 3 mM NaCl do not cause unacceptable yield losses in zucchini crops grown in completely closed hydroponic systems. [ABSTRACT FROM AUTHOR]

Pumpkin (Cucurbita pepo L.) is one of the popular seasonal vegetables cultivated in the world under different climatic conditions. This crop is important as a vegetable and medicinal plant used as a component in the diet. The aim of the experiment was to estimate the biodiversity of fungi colonizing pumpkin plants cultivated in the field and determine the strength of the interaction in communities of fungi, by using the biotic activity test. The experiment was set up in the organic farm in Zezulin (Lublin province, Poland) where the pumpkin plants 'Bambino' were cultivated in 2010 and 2012. The leaves, stems and roots of pumpkin were collected for mycological analysis at the beginning of fructification (71 BBCH). Laboratory test showed that predominating fungi colonizing plants were Alternaria alternata, Fusarium culmorum, Gibberella intricans, F. oxysporum and Tanatephorus cucumeris. The biotic interactions between the most important species fungi such as A. alternata, F. culmorum, F. oxysporum and other fungal species were studied using the biotic series method. Trichoderma spp. were found as the most effective and positive antagonists against Alternaria alternata, F. oxysporum and F. culmorum. It was show that A. alternata and F. oxysporum were weak competitors because their growth was limited by numerous fungi such as Trichoderma hamatum, Tanatephorus cucumeris and other fungi used in the test. F. culmorum was strong competitor because it limited the growth of other fungi from phyllosphere of pumpkin plants, however its growth can be inhibited by a great number of Trichoderma spp. colonies. [ABSTRACT FROM AUTHOR]