Pumpkin Species Research Articles

Conservation genomics of the wild pumpkin Cucurbita radicans in Central Mexico: The influence of a changing environment on the genetic diversity and differentiation of a rare species

The genetic diversity found in natural populations is the result of the evolutionary forces in response to historical and contemporary factors. The environmental characteristics and geological history of Mexico promoted the evolution and diversification of plant species, including wild relatives of crops such as the wild pumpkins (Cucurbita). Wild pumpkin species are found in a variety of habitats, evidencing their capability to adapt to different environments. Despite the potential value of wild Cucurbita as a genetic reservoir for crops, there is a lack of studies on their genetic diversity. Cucurbita radicans is an endangered species threatened by habitat destruction leading to low densities in small and isolated populations. Here, we analyze Genotype by Sequencing genomic data of the wild pumpkin C. radicans to evaluate the influence of factors like isolation, demographic history, and the environment shaping the amount and distribution of its genetic variation. We analyzed 91 individuals from 14 localities along its reported distribution. We obtained 5,107 SNPs and found medium-high levels of genetic diversity and genetic structure distributed in four main geographic areas with different environmental conditions. Moreover, we found signals of demographic growth related to historical climatic shifts. Outlier loci analysis showed significant association with the environment, principally with precipitation variables. Also, the outlier loci displayed differential changes in their frequencies in response to future global climate change scenarios. Using the results of genetic structure, outlier loci and multivariate analyses of the environmental conditions, we propose priority localities for conservation that encompass most of the genetic diversity of C. radicans.

Comparing the differences in quality profiles and antioxidant activity in seven pumpkin cultivars (Cucurbita moschata and Cucurbita maxima) at harvest and during postharvest storage

Pumpkin, nutritious vegetable, is renowned for its extended shelf life. In this study, seven pumpkin cultivars from Cucurbita moschata and Cucurbita maxima were comparatively characterized for 25 physiochemical quality factors, starch granule structures, antioxidant activity, and correlations at 0–60 days of postharvest (dop). The findings revealed that sucrose and carotenoid contents increased in C. moschata, while they initially increased and then decreased in C. maxima. Additionally, acidity, primarily driven by malic acid, decreased in C. maxima but increased in C. maxima. The starch content of C. moschata and C. maxima reached its maximum value at 30 dop and 20 dop, respectively. The DPPH radical scavenging activity correlated with the carotenoid content in both pumpkin species. Conclusively, C. moschata demonstrated improved nutritional and quality at 20–30 dop, while C. maxima exhibited higher commercial suitability at 10–20 dop. The findings suggested that pumpkin storage was crucial for quality improvement.

Bioactivity profiling of native and hybrid varieties of pumpkin peel (Cucurbita maxima Linn.)

The peel part of the two varieties (native and hybrid) of pumpkin are nutritionally enrich, so to make it economically viable it could be an important component in food and pharmaceutical industries. For this purpose, this study focus on to assess the various biological activities of two varieties of pumpkin peel. To evaluate the phytochemical potentiality of the peel of two varieties of pumpkin as a wide-ranging bioactivity profiling, in vitro anti-hyperglycemic activity, anti-inflammatory activity, anti-hemolytic activity and in vitro antioxidant activity along with total phenolic and flavonoid contents were evaluated. The peel of the native variety showed more phenolic contents than that of hybrid one and the values of the phenolic contents of the native and hybrid varieties were 74.76 ± 1.7 and 68.76 ± 0.87 mg GAEs/g respectively. In contrast, the peel of the hybrid variety showed more flavonoid content compared to native one and the values of the flavonoid contents of the native and hybrid varieties were 34.11 ± 0.13 and3 6.66 ± 1.29 mg QEs/g respectively. The two varieties exhibited concentration-dependent moderate antioxidant activity along with intermediate inhibitory activity against two enzymes. These activities were in order: native peel > hybrid peel. In the case of in vitro anti-hemolytic activity, both extracts showed intermediate erythrocyte membrane stabilization activities in order: hybrid peel > native peel. This research presented some supporting evidence for analyzing the comparative biological activities, and the findings could be helpful in enhancing a better understanding of these varieties as well as other pumpkin species. Finally, in this study, the bioactive compounds in the pumpkin peel may validate their enormous potential as a source of bio-based preservatives, an emergent component of functional food in food industries and in pharmaceutical industries as therapeutic agents that may enhance consumers’ health and promote a circular economy.

Convective drying of pumpkin: Brief literature review and new data for organically produced indigenous pumpkin (Cucurbita pepo L.) over an expanded temperature range

Selected cultivars form part of the neglected and underutilized species (NUS), which can contribute to building sustainable and resilient food systems, particularly for food-insecure households. Advances in the drying of pumpkin cultivars are briefly reviewed. Background on drying, including pretreatment techniques, is discussed. It emerged that convective air drying remains the most used dehydration technique, while most pretreatment and drying approaches, although innovative and promising, have not yet been investigated for pumpkin species. Areas for future scientific investigations are also suggested. A closer look at the literature data revealed notable inconsistencies for pumpkin diffusivity data even for the same species. For this reason, independently of the review, new data are reported in this study for the Cucurbita Pepo cultivar in a quest for more accuracy and a wider temperature validity range. A convective dryer using hot air was used to determine the drying characteristics of pumpkin (Cucurbita pepo L.) slices at four different temperatures (40, 45, 50, 55 and 65) °C at a constant velocity of 1.5 m/s. The extended temperature range and the large number of experimental temperatures were meant to increase the newly reported properties’ accuracy and validity range. The Page model stood out as the most accurate approach to describe the investigated dehydration process. Pumpkin effective diffusivity was calculated as 3.74–7.30 × 10−9 m2/s while the activation energy was 21.07 kJ/mol based on experiments undertaken in the present study. The newly obtained data did not solve the problem associated with inconsistencies between the two data sets found in the literature for drying the same pumpkin cultivar. The reported data would be helpful in the accurate determination of diffusivity data instrumental for convective drying process modelling and optimization.

A simplex PCR-based approach to trace the pulp adulterant of sweet pumpkin in industrially processed mango juice items by targeting the chloroplast ycf1 gene fragment

The phenomenon of incorporating sweet pumpkin pulp into industrially processed mango juice has been observed in various reports from Bangladesh in recent years due to the remarkable resemblance in the matrix and color of both fruits at their matured stage. The increasing prevalence of such incidents has become a growing concern for consumers due to the several potential health implications of sweet pumpkin. However, there is no reliable method available so far for the surveillance of this fraudulent activity. Therefore, the present study highlights a prompt and precise approach for tracing the origin of mango and pumpkin species in commercial mango juices based on a polymerase chain reaction. This approach involves the use of newly designed primer sets that target the chloroplast ycf1 genes and can produce the specific detectable amplicons of 206 and 70 bp from ≥ 10−4 and ≥ 10−3 ng/µl of total DNA for mango and pumpkin, respectively. Analyzing six samples of industrially produced mango juice, only four were traceable to their respective origins, and neither mango nor sweet pumpkin were detected in the two remaining samples. However, the non-reactive samples also did not succeed during performance analysis with a plant-specific universal primer set, indicating that the non-reactive samples may contain target unamplifiable or amplifiable DNA along with PCR inhibitors or non-target DNA without PCR inhibitors. Therefore, based on these consistent findings with the plant-specific universal primer set, the newly designed primer sets can be applied to pumpkin adulterant detection in commercial mango juice items.

Overview of Cucurbita spp. (pumpkin) and development of value-added products emphasizing its nutritional and chemical composition

Pumpkin (Cucurbita spp.) is a commonly grown vegetable across the world however, due to its underutilization as a food source a significant imbalance between pumpkin production and consumption has been identified. Many researchers have reported morphological diversity and differences in the nutritional and chemical composition among the pumpkin species which resulted in a selective distribution of Cucurbita species in different parts of the world. As evidenced from literature, pumpkin has been identified as a remarkable source of nutrients and reported with high protein, carbohydrate, vitamins, and especially with high amounts of antioxidants. Despite their nutritional value, post-harvest loss associated with pumpkins is significantly high which highlights the importance of utilization of pumpkins through value addition. The value addition of pumpkin has drawn a huge research interest over the past years which has emphasized the nutritional and chemical composition of pumpkin, especially in the edible (flesh, seeds) and non-edible (peel and pulp) fruits parts and pumpkin flowers in several value additions. This review furnishes an overview of Cucurbita spp. production and the post-harvest loss associated with pumpkin along with the updated information about the reported value additions based on existing literature.

Assessment of Phenolic Acid Content and Antioxidant Properties of the Pulp of Five Pumpkin Species Cultivated in Southeastern Poland.

Antioxidant properties and phenolic acid content in the pulp of five pumpkin species were evaluated. The following species cultivated in Poland were included: Cucurbita maxima 'Bambino', Cucurbita pepo 'Kamo Kamo', Cucurbita moschata 'Butternut', Cucurbita ficifolia 'Chilacayote Squash', and Cucurbita argyrosperma 'Chinese Alphabet'. The content of polyphenolic compounds was determined by ultra-high performance liquid chromatography coupled with HPLC, while the total content of phenols and flavonoids and antioxidant properties were determined by spectrophotometric methods. Ten phenolic compounds (protocatechuic acid, p-hydroxybenzoic acid, catechin, chlorogenic acid, caffeic acid, p-coumaric acid, syringic acid, ferulic acid, salicylic acid, kaempferol) were identified. Phenolic acids were the most abundant compounds; the amount of syringic acid was found to be the highest, ranging from 0.44 (C. ficifolia) to 6.61 mg∙100 g-1 FW (C. moschata). Moreover, two flavonoids were detected: catechin and kaempferol. They were found at their highest level of content in C. moschata pulp (catechins: 0.31 mg∙100 g-1 FW; kaempferol: 0.06 mg∙100 g-1 FW), with the lowest amount detected in C. ficifolia (catechins: 0.15 mg∙100 g-1 FW; kaempferol below the limit of detection). Analysis of antioxidant potential showed significant differences depending on the species and the test used. The DPPH radical scavenging activity of C. maxima was 1.03 times higher than C. ficiofilia pulp and 11.60 times higher than C. pepo. In the case of the FRAP assay, the multiplicity of FRAP radical activity in C. maxima pulp was 4.65 times higher than C. Pepo pulp and only 1.08 times higher compared to C. ficifolia pulp. The study findings show the high health-promoting value of pumpkin pulp; however, the content of phenolic acids and antioxidant properties are species dependent.

Comparative assessment of pumpkin varieties in the Udmurt Republic

Relevance. Pumpkin is a food, medicinal and fodder crop of the Cucurbitaceae family. It is valued for its high content of vitamins, minerals, organic acids. At present, thanks to the huge variety of species and modern selection, it is possible to select pumpkin varieties for cultivation in almost any region, including areas with short and not too hot summers. Udmurtia belongs to the zone of risky farming, the end of spring frosts is observed on average in the first ten days of June, and autumn frosts on the soil are possible at the end of August. Due to the short frost-free period, it is necessary to choose earlier maturing varieties, grow the crop through seedlings and use temporary shelters. The pumpkin fruit is usually large in size, is a thick layer of pulp, covered with a dense peel. When cutting such a fruit, the pumpkin is not stored in the future, it requires urgent processing. In this connection, in recent years, portioned varieties of pumpkin, the size of the fruit of which does not exceed 1.5–3.0 kg, have become increasingly in demand.Materials and Methods. The purpose of the research: a comparative assessment of varietal characteristics of growth and productivity of pumpkin species. In 2020–2021 in the conditions of the Udmurt Republic, experiments were carried out to study the characteristics of growth and productivity of pumpkin varieties. We studied varieties of pumpkin: Pearl, Crumb, Honey Tale, Marble, Rossiyanka, Smile, Candied fruit.Results and its discussion. Within two years, pumpkin varieties of large-fruited and nutmeg were studied. On average, for two years, the pumpkin Medovaya skazka distinguished itself with the highest yield. In 2021, the yield for the Medovaya Skazka variety was 64.7 t/ha. The yield increase was obtained due to an increase in fruit weight, which in 2020 amounted to 2.9 kg, in 2021 - 6.5 kg. The studied varieties of pumpkin differed in quality indicators of fruits. On average, over two years, the varieties Rossiyanka and Mramornaya showed an increase in the content of water-soluble sugars in fruits. The fruits of the pumpkin Candied fruit and Kroshka were distinguished by a high content of dry matter.

Carotenoid Content and Profiles of Pumpkin Products and By-Products.

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.

Biological Activity of Pumpkin Byproducts: Antimicrobial and Antioxidant Properties

Pumpkin fruits are widely appreciated and consumed worldwide. In addition to their balanced nutritional profile, pumpkin species also present valuable bioactive compounds that confer biological and pharmacological properties to them. However, the seeds, peels, and fibrous strands resulting from pumpkin processing are still poorly explored by the food industry. The current study used those fruit components from the genotypes of pumpkin that are economically significant in Portugal and Algeria to produce bioactive extracts. In order to support their usage as preservatives, their phenolic content (HPLC-DAD-ESI/MS) and antioxidant (OxHLIA and TBARS) and antimicrobial properties (against eight bacterial and two fungal strains) were assessed. In terms of phenolic profile, the peel of the Portuguese 'Common Pumpkin' showed the most diversified profile and also the highest concentration of total phenolic compounds, with considerable concentrations of (-)-epicatechin. Regarding the antioxidant capacity, the seeds of 'Butternut Squash' from both countries stood out, while the fibrous strands of Portuguese 'Butternut Squash' and the seeds of Algerian 'Gold Nugget Pumpkin' revealed the strongest antimicrobial activity. The bioactive compounds identified in the pumpkin byproducts may validate their enormous potential as a source of bio-based preservatives that may enhance consumers' health and promote a circular economy.

Volatiles and Transcriptome Profiling Revealed the Formation of ‘Taro-like’ Aroma in the Leaf of Pumpkin (Cucurbita moschata)

‘Taro-like’ odor is an important economic trait of pumpkin species. The metabolic and molecular bases of this aromatic trait remain largely unexplored. Therefore, in this study, gas chromatography-mass spectrometry, GC-Olfactometry, and RNA-seq technology were used to illuminate the differential volatile compounds, the key volatile compounds, and differentially expressed genes (DEGs) in leaves from two pumpkin samples. Eight volatile compounds, including (E)-2-nonenal, 3-octanol, 2-ethyl-1-hexanol, 1-nonanol, α-terpineol, 2,3-pentanedione, caryophyllene, and 2-acetyl-1-pyrroline, were only detected in the sample with ‘taro-like’ aroma. Moreover, the variable importance in projection scores of all the above eight volatile compounds were >1.0 using PLS-DA analysis. The compounds 2-acetyl-1-pyrroline, 3-octanol, 1-nonanol, and (E)-3,7-dimethyl-2,6-octadienal were identified as the key contributors using GC-Olfactometry analysis. It was determined that 2-acetyl-1-pyrroline might play a significant role in ‘taro-like’ aroma. Furthermore, most of the differential volatile compounds were derived from fatty acids, and the DEGs were also involved in the pathways related to degradation, metabolism, and biosynthesis of fatty acids. Moreover, five genes involved in the accumulation of 2-acetyl-1-pyrroline showed differential expression, and their expression trends were consistent with 2-acetyl-1-pyrroline. This study offers the basis for further studies on the mechanism of ‘taro-like’ aroma in pumpkins.

Assessment of the 'taro-like' aroma of pumpkin fruit (Cucurbita moschata D.) via E-nose, GC-MS and GC-O analysis.

'Taro-like' aroma is a pleasant flavor and value-added trait in pumpkin species imparted by unknown key volatile compounds. In this study, we used the electronic nose (E-nose), gas chromatography-mass spectrometry (GC-MS), and GC-Olfactometry (GC-O) to study the aroma profile, volatile compounds, and keycontributors, respectively. By E-nose and GC-MS, we found significant differences in the aroma profiles and volatile compounds between fruits from five samples with/without 'taro-like' aroma. According to the analysis of differential volatile compounds obtained from GC-MS and the GC-O analysis of the sample with 'taro-like' aroma, we found that 2-acetyl-1-pyrroline representing the 'taro' odor was only identified in the sample with 'taro-like' aroma. Therefore, we conclude that 2-acetyl-1-pyrroline is the key contributor to the 'taro-like' aroma. Moreover, the relationship between 2-acetyl-1-pyrroline and 'taro-like' aroma was further verified via other pumpkin samples. Our results provide a theoretical basis for understanding the aroma characteristics of pumpkin fruit.

Contrasting Metabolic Fingerprints and Seed Protein Profiles of Cucurbita foetidissima and C. radicans Fruits from Feral Plants Sampled in Central Mexico.

Cucurbita foetidissima and C. radicans are scarcely studied wild pumpkin species that grow in arid and semi-arid areas of Mexico and the United States. This study describes the morphological, proximal composition, metabolic finger-prints and seed protein profiles of C. foetidissima and C. radicans fruits collected in the wild during a one-year period in different locations of central-western Mexico. The results obtained complement the limited information concerning the fruit composition of C. foetidissima and greatly expand information in this respect regarding C. radicans. Morphology and proximal composition of their fruits varied significantly. Different metabolic fingerprints and seed protein profiles were detected between them and also with the chemical composition of domesticated Cucurbita fruits. The neutral lipids in seed, pulp and peels were rich in wax content and in unsaturated compounds, probably carotenoids and tocopherols, in addition to tri-, di- and mono-acylglycerols. The tri- and diacylglycerol profiles of their seed oils were different from commercial seed oils and between each other. They also showed unusual fatty acid compositions. Evidence of a possible alkaloid in the pulp and peel of both species was obtained in addition to several putative cucurbitacins. An abundance of phenolic acids was found in all fruit parts, whereas flavonoids were only detected in the peels. Unlike most cucurbits, globulins were not the main protein fraction in the seeds of C. radicans, whereas the non-structural carbohydrate and raffinose oligosaccharide content in their fruit parts was lower than in other wild cucurbit species. These results emphasize the significantly different chemical composition of these two marginally studied Cucurbita species, which was more discrepant in C. radicans, despite the notion regarding C. foetidissima as an aberrant species with no affinity to any other Cucurbita species.

Targeted Sequencing Suggests Wild-Crop Gene Flow Is Central to Different Genetic Consequences of Two Independent Pumpkin Domestications

Studies of domestication genetics enrich our understanding of how domestication shapes genetic and morphological diversity. We characterized patterns of genetic variation in two independently domesticated pumpkins and their wild progenitors to assess and compare genetic consequences of domestication. To compare genetic diversity pre- and post-domestication and to identify genes targeted by selection during domestication, we analyzed ∼15,000 SNPs of 48 unrelated accessions, including wild, landrace, and improved lines for each of two pumpkin species, Cucurbita argyrosperma and Cucurbita maxima. Genetic diversity relative to its wild progenitor was reduced in only one domesticated subspecies, C. argyrosperma ssp. argyrosperma. The two species have different patterns of genetic structure across domestication status. Only 1.5% of the domestication features identified for both species were shared between species. These findings suggest that ancestral genetic diversity, wild-crop gene flow, and domestication practices shaped the genetic diversity of two similar Cucurbita crops in different ways, adding to our understanding of how genetic diversity changes during the processes of domestication and how trait improvement impacts the breeding potential of modern crops.

A practical chemometric approach using UPLC–QTOF/MS tool to investigate three varieties of pumpkin species and in vitro bioactivities

The OPLS-DA, the UPLC–QTOF/MS and chemometric approaches were adopted to discriminate the different varieties belonging to three pumpkin species. Furthermore, this study included a comparison of the phenolic metabolites, antioxidant (DPPH, FRAP and ABTS activity), in vitro α-glucosidase and α-amylase activities, and cell cytotoxicity of the leaves of three varieties of pumpkin species (Cucurbita moschata, C. maxima, and C. pepo).Leaves of all three varieties of pumpkin species contained 23 phenolic metabolites. The OPLS-DA, the UPLC–QTOF/MS and chemometric approach showed that genistin was the candidate biomarker responsible for the separation of butternut squash (C. maxima) from the other two species, while 7-methylquercetin-3-galactoside-6″-rhamnoside-3‴-rhamnoside separated the Caserta squash (C. pepo) from the other two pumpkin species. Leaves of Green Hubbard (C. maxima) showed the highest antioxidant capacity (FRAP and ABTS activities), while butternut squash (C. moschata) showed the highest DPPH scavenging activity. Leaf extracts of butternut squash (C. moschata) and Green Hubbard (C. maxima) showed higher inhibition of α-glucosidase activity (IC50 18.22 μg mL−1) and α-amylase (IC50 18.11 μg mL−1) activities respectively, with no cytotoxic effect detected.The phenolic metabolites identified herein for the leaves of each variety of pumpkin species can be potential control markers for further standardisation. Leaves of Green Hubbard (C. maxima) provides functional properties for health benefits.

Influence of Different Types of Drying Methods on Color Properties, Phenolic Metabolites and Bioactivities of Pumpkin Leaves of var. Butternut squash (Cucurbita moschata Duchesne ex Poir).

Leaves of pumpkin species var. Butternut squash (Cucurbita moschata Duchesne ex Poir) is a popularly consumed leafy vegetable in the Southern African region. Traditional vegetables are commonly sun-dried as a method of postharvest preservation during the off-season. However, different drying methods affect the superior quality, functional properties, and bioactivities of the final product. Therefore, in this study, var. Butternut squash (C. moschata) underwent different drying methods, such as freeze-, oven, sun-, solar, and microwave drying to evaluate the color properties, pigments, phenolic metabolites, in vitro antioxidants, and antidiabetic activities. Results indicate that freeze-drying retained the total chlorophyll content with green color by reducing the color difference (ΔE), improved the concentration of different phenolic metabolites and the content of ascorbic acid, and enhanced the FRAP, ABTS activities and the inhibitory effects of α-glucosidase, and α-amylase. Freeze-dried leaves contained the highest concentrations of quercetin 3-glucoside 7-rhamnoside (rutin), quercetin 3-galactoside, isorhamnetin-3-galactoside-6″-rhamnoside, isorhamnetin-3-O-rutinoside compared with the leaves that underwent four other drying treatments and raw leaves. The OPLS-DA and the UPLC–QTOF/MS and chemometric approach showed that the peak at m/z 609, 1441 (quercetin 3-galactoside 7-rhamnoside) separated the freeze-dried leaves of var. Butternut squash (C. moschata) from the other four drying treatments. Therefore, freeze-drying is highly recommended to obtain good quality leaf powders that are rich in functional compounds and bioactive properties for use as functional ingredients.

ЭФФЕКТИВНОСТЬ ПРИМЕНЕНИЯ ОТЕЧЕСТВЕННЫХ ПОДВОЕВ ТЫКВЫ ДЛЯ ПРИВИВКИ ОГУРЦА В ЗАЩИЩЕННОМ ГРУНТЕ

When growing herbaceous vegetable crops in the world practice, great importance is given to the use of grafting method. The development of environmentally safe methods to increase the yield and resistance of plants to adverse growing conditions is very relevant in vegetable production. One such method in pumpkin crops is grafting. The aim of our work was to study the effect of domestic pumpkin rootstock on growth, development and yield characteristics of cucumber hybrid using grafting method. Grafting on pumpkin species improved the growth and development of plants depending on the rootstock, compared with rootstock plants. The aim of our research was to study the influence of domestic pumpkin rootstock on the growth, development and yield characteristics of the cucumber hybrid (scion). As a scion, the variety (Asylum), recommended for cultivation in protected ground conditions, was used, which was grafted on five domestic rootstocks: 1 (Mozoleevskaya 10), 2 (Karina), 3 (Aphrodite), 4 (Mindalnaya) and Russian selection 5 (Stofuntovaya) pumpkins from vegetable and melon crops. According to the generally accepted method, the graft was grafted (cucumber Asylum) on the rootstocks of pumpkin. Using a sample of pumpkin 1 (Mozoleevskaya 10), flowering began on the fifth day earlier in comparison with non-grafted plants, and when grafting on a sample of pumpkin 4 (Aphrodite), the fruit ripened earlier by six days. To get the greatest increase in early productivity by 30%, it is possible to use both rootstocks. A significant increase in total yield was provided by samples of rootstocks 2 (Karina) – 3.9 kg/m2 and 3 (Stofuntovaya) - 8.0 kg/m2. The grafted cucumber plants with all the rootstocks used were superior to the root ones in height, in terms of the percentage of marketability of fruits and in terms of fruit weight. At the beginning of fruiting on grafted cucumber plants, the number of female flowers increased depending on the sample. In all grafted plants, the dry matter content in the fruit increased significantly. Because of our research, rootstocks 2 (Karina) and 3 (Stofuntovaya) were noted, which are recommended for use in further research breeding work and the production of grafted plants.

Pollination of Cucurbita spp. (squash and pumpkin) crops in Florida

Squash and pumpkin (Cucurbita spp.) are economically significant crops in Florida with over 7,900 acres in production and an estimated value of $35,412,000. Without insect pollination, however, crop yields for zucchini, crookneck, spaghetti, butternut and the rest of the large and delectable crew of squash and pumpkin species grown in Florida would be low to nonexistent. This 7-page fact sheet written by Rachel E. Mallinger and Oscar E. Liburd and published by the UF/IFAS Entomology and Nematology Department explains the pollination biology and requirements for squash and pumpkin, describes the signs and causes of poor pollination, and provides recommendations for improving pollination of these crops in Florida.<

Physicochemical properties and stability of pumpkin seed oil as affected by different extraction methods and species

The present work evaluated the influence of extraction method and species on the physicochemical properties, oxidative stability, fatty acid profiles, and rheological behaviour of pumpkin seed oils. The seeds of two pumpkin species (Cucurbita argyrosperma Huber [CA] and Cucurbita moschata Duchesne [CM]) were obtained from small-scale pumpkin processors in Yucatán, Mexico. The oils were extracted by two methods: mechanical pressing (MP) and organic solvent (OS). It was found that the oil extraction method, species, and their interaction significantly influenced the physicochemical properties and oxidative stability of the seed oils. The composition and fatty acid content of the oils were comparable to those of other pumpkin species. The oil yield from the MP method was lower than that from the OS method. Also, CA oil extracted by MP had an olive-green colour as compared to the reddish-yellow colour of CM oil, and also had a higher oxidative stability. The viscosity of CA oil extracted by MP was superior to that extracted by OS. Also, CA oil had a higher content of iron, monounsaturated fatty acids (MUFA), stearic acid, and oleic acid as well as viscosity in comparison to CM oil, although CM oil had a higher content of linoleic acid. This information can be used to obtain more stable pumpkin oils with enhanced properties that would benefit both producers and processors.

DISTRIBUCIÓN ACTUAL, POTENCIAL Y ECOFISIOGRÁFICA DE ESPECIES DE CALABAZA EN NAYARIT, MÉXICO

La calabaza (Cucurbita spp.) es un género originario de América, del cual algunas especies importantes son originarias de México, tiene arraigo cultural y es utilizada en la alimentación humana y animal, por lo que su aprovechamiento, mejoramiento y conservación son esenciales. El objetivo de esta investigación fue generar mapas de distribución actual y potencial de especies de calabaza cultivadas y silvestres, así como precisar su distribución ecofisiográfica en el estado de Nayarit, México. Se utilizaron 114 registros de sitios georreferenciados de especies domesticadas (Cucurbita moschata, C. pepo, C. argyrosperma y C. ficifolia) y silvestres (C. radicans, C. martinezii) provenientes de 66 accesiones y 48 registros de herbarios. Se emplearon 110 variables bioclimáticas, geofísicas y edáficas. Para su análisis se utilizaron herramientas de sistemas de información geográfica (SIG) y procedimientos multivariados de componentes principales (CP) y de conglomerados. La distribución actual mostró que las especies de calabazas se encuentran presentes en las cuatro regiones fisiográficas del estado de Nayarit, entre alturas de 7 a 2117 msnm. La distribución potencial permitió la ubicación de sitios no registrados con probable presencia de calabazas. En la distribución ecofisiográfica, tres CP representaron el 77 % de la variabilidad total, las variables que mostraron mayor correlación con el CP1 fueron altitud (m) y temperatura (°C), con el CP2 precipitación (mm), características de suelo (textura, profundidad y pH) y velocidad del viento (km h-1) y con el CP3 precipitación de los tres meses más fríos del año. En especies de calabaza esta información permitirá ubicar áreas de probable presencia para exploraciones más dirigidas, conocer las condiciones ambientales de sus hábitats y utilizarla en futuros programas de conservación.