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Simple Summary: The sweetpotato whitefly, Bemisia tabaci Gennadius Middle East–Asia Minor 1 (MEAM1), is an economically important vegetable worldwide. This study evaluated the susceptibilities of yellow squash and zucchini cultivars to MEAM1 across three growing seasons in the southeastern United States: summer 2021, fall 2021, and fall 2022. Commercially available cultivars squash and zucchini were examined for resistance to MEAM1 infestations and yield performance. Weekly MEAM1 adult, egg, and nymph counts were conducted over 5 (fall 2022) or 6 (summer and fall 2021) weeks beginning after the third week of planting in each season. In general, MEAM1 adult populations were high at the first week of sampling but decreased in the subsequent weeks. The Zucchini cultivar 'Black Beauty' had the highest number of MEAM1 adults, and 'Green Eclipse Zucchini' had the lowest adult counts in summer 2021. For yellow squash, 'Early Summer' and 'Amberpic 8455' were identified as the cultivars that harbored the highest populations of adults in 2021, whereas 'Golden Goose Hybrid' harbored the least number of adult infestations in fall 2022. Generally, MEAM1 egg counts trailed adult peak populations. For yield performance, 'Gourmet Gold Hybrid', 'Lioness', 'Fortune', and 'Golden Glory' achieved the highest yields. These results provide valuable information for whitefly management in yellow squash and zucchini based on host plant resistance and yield. The sweetpotato whitefly, Bemisia tabaci (Gennadius) Middle East–Asia Minor 1 (MEAM1), causes significant losses to vegetable crops directly by sap-feeding, inducing plant physiological disorders, and elevating the build-up of sooty mold, and indirectly by transmitting plant viruses. In this study, we evaluated the susceptibility of 20 yellow squash and zucchini (Cucurbita pepo) cultivars to MEAM1, across three growing seasons in the southeastern United States. Weekly sampling of the numbers of MEAM1 adults, nymphs, and eggs were conducted from the fourth week after seed sowing and across 6 weeks during the summer and fall of 2021 and five weeks during the fall of 2022. In general, adult whitefly populations were high during the first week of sampling but decreased as the seasons progressed. The zucchini cultivar 'Black Beauty' harbored the most adults, while 'Green Eclipse Zucchini' was the least attractive zucchini cultivar to the adults in fall 2022. For yellow squash, 'Early Summer' (summer 2021) and 'Amberpic 8455' (summer 2021 and fall 2022) were the cultivars with the highest adult populations, while 'Lioness' (summer 2021) and 'Gourmet Gold Hybrid' (fall 2022) harbored the lowest adult counts. The whitefly egg counts across both vegetables trailed those of adults and peaked in the second week of sampling. The counts of nymphs increased as the seasons progressed, but there was a decline after the second week during fall 2021. For the yellow squash cultivars, 'Gourmet Gold Hybrid', (summer 2021 and fall 2022), 'Lioness', and 'Fortune' (summer 2021) recorded the highest yields. For zucchini, 'Golden Glory' (summer 2021) was the top performer. These results provide valuable information for whitefly management in yellow squash and zucchini based on host plant susceptibility and yield. [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.)

Acorn squash (Cucurbita pepo) have been a familiar item at produce stands for decades in the United States and Canada, but little known or appreciated elsewhere. Following the breeding and development of sweet-fleshed acorn squash in Israel and its commercial introduction in 2007, acorn squash became a high-priced, popular produce item there. Scarcity of supply in winter has led to attempts to fill the consumer demand by using available protected cultivation infrastructure in the relatively mild area of southwestern Israel for production. Such production has proven feasible but it was not determined whether it would be preferable to allow the plants to simply grow sprawling on the ground or vertically, using trellises to train the plants to grow erect. Two sweet acorn squash hybrid cultivars differing in fruit size were compared, growing on the ground or on trellises, for yield, quality, and storability of the fruits. The hybrids bore fully ripe fruits from December through February, producing 56% higher yields when trellised rather than when allowed to grow on the ground. The fruits of trellised plants of both hybrids were more uniformly black-green and firmer than those of ground-grown plants. Their dry matter content at harvest and after 78 days of storage was very high, averaging 28% and 25%, respectively. Total soluble solids content of the fruit flesh from trellised plants was 19% at harvest and an extraordinary 20% after storage at 10°C, 70% RH. The fruit flesh of trellised plants was also more highly colored and had higher carotenoid, ascorbate, and anti-oxidant contents. Overall, trellising of sweet acorn squash during the winter under protected cultivation resulted in significantly higher yields and the finest fruit quality. [ABSTRACT FROM AUTHOR]

A new disease syndrome of zucchini squash was observed in Southern Italy, in 2018 and again in 2020. Affected plants were severely stunted and leaves were bent downwards, small, stiff, thick, leathery, and had interveinal chloroses. In addition, flowers were virescent and fruits were deformed and often cracked. Disease incidence was 20 and 30% in two different zucchini cultivations in Campania region (Southern Italy). Tomato yellow leaf curl New Delhi virus (ToLCNDV) was detected in eight samples, by loop-mediated isothermal amplification-based (LAMP) kit and by PCR and Sanger sequencing of the AV1 gene. Phytoplasmas were detected in the same samples using nested PCR assays with primer pairs P1/P7 and R16F2n/R16R2. Phytoplasma associations in plant samples were confirmed using specific primers for the multilocus genes SecY, tuf and rp. Sequence comparison of multilocus genes and phylogenetic analyses of the 16S rDNA gene confirmed the association of a phytoplasma strain closely related to 'Candidiatus Phytoplamsa asteris'. This is the first report of mixed infections of ToLCNDV and a putative 'Ca. Phytoplamsa asteris' strain in zucchini, associated with a new Squash-Phytoplasma-Begomovirus (SqPB) disease syndrome. [ABSTRACT FROM AUTHOR]

In this Experiment, the impact of "Dielectric Barrier Discharge (DBD) Plasma jet" (5.47 watt) on activation and germination of Squash seeds (Cucurbita pepo L.) is studied at various periods. The seeds are divided into (soaked seeds and dry seeds). After exposing the seeds, measurements are taken for three germination characteristics (root length, shoot length, and number of leaves). The results show that exposing the plasma jet on the seeds soaked with water is better than dry seeds. Results of plasma exposure on soaked plant seeds at root length at exposure time (5 minutes) show superiority to control by 15.80% while there is no effect at (0.5 minutes) on dry seeds is shown during different exposure times (0.5, 1, 3, 5 min), and a clear increase is shown in shoot length and number of leaves compared to the control group. This indicates that the discharge of the plasma dielectric barrier contributes to stimulating the seeds and increasing their germination rate. [ABSTRACT FROM AUTHOR]

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]

This study was aimed to investigate combining ability and genetic parameters in summer squash (cucurbita pepo L.). Eight inbred lines of summer squash were crossed in line x tester method in summer season 2020. The parental lines (3 tester and 5 lines) and their off springs (15 hybrids) were planted out in the summer season 2021 at vegetable field, Horticulture Department, College of Agricultural Engineering Science, Duhok University. The experiment lay out using randomized complete block design with three replications. The results indicated that the mean square for genotypes were highly significant effect for tester, line and line x tester in all studied traits. The Tester LBL2 and line PEP1670 were the best combiner for days to 50% female flowering, number of fruit plant-1 and yield kg plant-1 . The crosses (LBL2 X N33133) and (LES3 X CNS2881) exhibited significant positive effect of specific combining ability for fruit length cm, number of fruit plant-1 and yield plant-1 . The heritability in broad sense were higher than narrow sense heritability for all studied traits ranged between 93% for days to 50% female flowering to 40% for fruit weight. The average degree of dominance less than one in all traits except days to 50% female flowering and fruit length. [ABSTRACT FROM AUTHOR]

Summer squash cultivation is becoming more and more popular among farmers due to its increased nutritional content, short growing season, and quicker economic payoff. Although there is a respectable amount of production, India’s productivity is extremely poor which is big worry for the commercial cultivation of summer squash and the environmental factors causes low productivity. In order to boost production and productivity, raise the number of female flowers, increase profitability for small and marginal farmers, and combat environmental conditions, plant growth regulators play a significant role in this crop. Therefore, by introducing the use of plant growth regulators, summer squash cultivation farmers’ income and yield can be raised. The investigation was carried out at the farmer’s field at Sorakalnatham, Natrampalli taluk, Tirupattur district, Tamil Nadu during February- April 2023 to study the plant growth regulators on the performance of summer squash. The experiment was laid out in randomized block design with thirteen treatments replicated thrice. The treatments were included different concentrations of Naphthalene acetic acid (50, 100, 150 ppm), Gibberellic acid (50, 100, 150ppm), Ethrel (150, 200, 250ppm), Malichydrazide (150, 200, 250ppm), and Control (water spray). The results indicated that the maximum values for growth attributes viz., plant height (78.32 cm), number of branches/plant (3.86) and leaf area (375.29 cm2 ), flowering and yield attributes viz., number of female flower/plant (11.85), number of fruits /plant (8.67), fruit set % (73.16), fruit length (44.06 cm), single fruit weight (1.37 kg), fruit yield /plant (11.37 kg) and lowest number of male flower/plant (20.69), sex ratio (1.75) were recorded in the foliar application of plant growth regulator NAA @ 100 ppm. This was followed by the foliar application of plant growth regulators ethrel @ 150 ppm. Significant differences were observed with the use of growth regulators on growth, flowering and yield traits of summer squash. [ABSTRACT FROM AUTHOR]

This study evaluated the quantitative and qualitative traits of 13 local summer squash populations. The experiment was carried out in a randomized block design with 3 replications for two years (2019 to 2020). The following traits were considered in this study: number, weight, length, width, and length/width ratio of fruits, seed yield, seed yield/fruit yield ratio, 1000 seeds weight, percentage of empty seeds, seed length, seed width, seed kernel/whole seed ratio, and seed oil percent. Also, quality tests were conducted including ease of separation of skin from the kernel, taste quality, and desirability of seed shape and size from the consumer's point of view. The analysis of variance showed significant differences in most of the studied traits. Based on the results of the mean comparison of traits, the highest seed yield was observed in Ghalami- Kalaleh#1 and Mashhady-Azadshahr and then Mashhady-Khoy populations. The highest taste quality from the consumer point of view belonged to the Goushti-Kalaleh population. The results represent a positive and highly significant correlation between seed yield and fruit number. No significant correlation was observed between seed yield and other related traits. It is recommended that fruit number trait be considered in selecting programs and modifying high-yielding populations. [ABSTRACT FROM AUTHOR]

The expansion of agriculture is responsible for the mass conversion of biologically diverse natural environments into managed agroecosystems dominated by a handful of genetically homogeneous crop species. Agricultural ecosystems typically have very different abiotic and ecological conditions from those they replaced and create potential niches for those species that are able to exploit the abundant resources offered by crop plants. While there are well-studied examples of crop pests that have adapted into novel agricultural niches, the impact of agricultural intensification on the evolution of crop mutualists such as pollinators is poorly understood. We combined genealogical inference from genomic data with archaeological records to demonstrate that the Holocene demographic history of a wild specialist pollinator of Cucurbita (pumpkins, squashes, and gourds) has been profoundly impacted by the history of agricultural expansion in North America. Populations of the squash bee Eucera pruinosa experienced rapid growth in areas where agriculture intensified within the past 1,000 y, suggesting that the cultivation of Cucurbita in North America has increased the amount of floral resources available to these bees. In addition, we found that roughly 20% of this bee species' genome shows signatures of recent selective sweeps. These signatures are overwhelmingly concentrated in populations from eastern North America where squash bees were historically able to colonize novel environments due to human cultivation of Cucurbita pepo and now exclusively inhabit agricultural niches. These results suggest that the widespread cultivation of crops can prompt adaptation in wild pollinators through the distinct ecological conditions imposed by agricultural environments. [ABSTRACT FROM AUTHOR]

RNA silencing is a crucial mechanism of the antiviral immunity system in plants. Small RNAs guide Argonaut proteins to target viral RNA or DNA, preventing virus accumulation. Small RNA profiles in Cucurbita pepo line PI 420328 with tolerance to cucurbit yellow stunting disorder virus (CYSDV) were compared with those in Gold Star, a susceptible cultivar. The lower CYSDV symptom severity in PI 420328 correlated with lower virus titers and fewer sRNAs derived from CYSDV (vsRNA) compared to Gold Star. Elevated levels of 21- and 22-nucleotide (nt) size class vsRNAs were observed in PI 420328, indicating more robust and efficient RNA silencing in PI 420328. The distribution of vsRNA hotspots along the CYSDV genome was similar in both PI 420328 and Gold Star. However, the 3' UTRs, CPm, and p26 were targeted at a higher frequency in PI 420328. [ABSTRACT FROM AUTHOR]

Potassium is an essential nutrient for the physiological and biochemical activities of a plant. Therefore, an adequate dose and source of this nutrient can increase zucchini squash production. This study aimed to evaluate the yield response of the zucchini squash cultivar 'Caserta' to different doses and sources of potassium. The experiment was conducted under field conditions in a completely randomized block experimental design in a 6 × 2 factorial scheme, with six K2O doses (0, 50, 100, 150, 200, and 250 kg ha-1) and two sources (potassium chloride and potassium sulfate), with four replicates. Fruit mass, fruit length, number of fruits per plant, and total and marketable fruit yields were evaluated. Fertilization with potassium sulfate and chloride sources increased fruit length and the number of fruits per plant. Potassium (K2O) fertilization using potassium sulfate resulted in higher mass and total fruit yield. K2O doses of 108.41 and 130.78 kg ha-1 in the potassium chloride and sulfate sources, respectively, provided the maximum marketable yield of fruits, at 22.84 and 27.0 t ha-1, respectively. Doses of 108.41 kg ha-1 of potassium chloride and 130.78 kg ha-1 of potassium sulfate are recommended for a better commercial yield, with potassium sulfate being the best recommendation. [ABSTRACT FROM AUTHOR]

Moisture and potassium deficiency are two of the main limiting variables for squash crop performance in many water-stressed places worldwide. If major output decreases are to be avoided, it is critical to detect signs of crop stress as early as possible in the growth cycle. Proximal remote sensing can be a reliable technique for offering a rapid and precise instrument and localized management tool. This study tested the ability of proximal hyperspectral remotely sensed data to predict squash traits in two successive seasons (spring and fall) with varying moisture and potassium rates. Spectral data were collected from drip-irrigated squash that had been treated to varied rates of irrigation and potassium fertilization over both investigated seasons. To forecast potassium-use efficiency (KUE), chlorophyll meter (Chlm), water-use efficiency (WUE), and seed yield (SY) of squash, different commonly used and newly-introduced spectral index values for three bands (3D-SRIs), as well as a Decision Tree (DT) model, were evaluated. The results revealed that the newly constructed three-band SRIs based on the wavelengths of the visible (VIS), near-infrared (NIR), and red-edge regions were sensitive enough to measure the four tested parameters of squash in this study. For instance, NDI558,646,708 presented the highest R2 of 0.75 for KUE, NDI744,746,738 presented the highest R2 of 0.65 for Chlm, and NDI670,628,392 presented the highest R2 of 0.64 for SY of squash. The results further demonstrated that the principal component analysis (PCA) demonstrated the ability to distinguish moisture stress from potassium deficiency stress at the flowering stage onwards. Combining 3D-SRIs, DT-based bands (DT-b), and the aggregate of all spectral characteristics (ASF) with DT models would be an effective strategy for estimating four observed parameters with appropriate accuracy. For example, the model's approximately 30 spectral characteristics were extremely important for predicting KUE. Its outputs with R2 were, for the training and validation datasets, 0.967 (RMSE = 0.175) and 0.818 (RMSE = 0.284), respectively. For measuring Chlm, the DT-DT-b-20 model demonstrated the best. In the training and validation datasets, the R2 value was 0.993 (RMSE = 0.522) and 0.692 (RMSE = 2.321), respectively. The overall outcomes showed that proximal-reflectance-sensing-based 3D-SRIs and DT models based on 3D-SRIs, DT-b, and ASF could be used to evaluate the four tested parameters of squash under different levels of irrigation regimes and potassium fertilizer. [ABSTRACT FROM AUTHOR]

Squash (Cucurbita pepo L.) is a globally important vegetable, the production of which is severely constrained by powdery mildew caused by Podosphaera xanthii. In this study, we examined the effects of Trichoderma asperellum (MW965676), Streptomyces rochei (MN700192), and a mixture of the two foliar sprays with or without shikimic acid seed priming treatment on powdery mildew severity, plant growth, and total yield during the 2020–2021 and 2021–2022 growing seasons. We also studied their immune eliciting properties by examining their enzymatic, phenolic, and hormonal functions. The combination of Trichoderma asperellum, Streptomyces rochei, and shikimic acid triggered plant defense responses, which elicited enzyme activities such as peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), phenolic compound accumulation, and increased salicylic acid (SA) and jasmonic acid (JA) content. This approach yielded high-quality results in the control of powdery mildew during the two growing seasons under greenhouse conditions. Additionally, relatively large statistical differences in plant growth, total yield, mineral components, and physiological traits were observed. A GC–MS analysis of Trichoderma asperellum (MW965676) showed hemin cation as a major component, while Streptomyces rochei (MN700192) contained 2,4-di-tert-butyl phenol and the hexadecenoic acid methyl ester. With respect to the morphological changes induced by powdery mildew and the treatments, plants treated with a mixture of Trichoderma asperellum, Streptomyces rochei and shikimic acid showed an improvement in the thickness of the midvein, increased dimensions of the main midvein bundle, a larger number of xylem rows in the main midvein bundle, greater mean diameters of vessels and of parenchyma cells in the ground tissues, as well as increased thickness of the upper and lower epidermis, lamina, palisade tissue and spongy tissue. This extensive, new study is the first step toward a more profound understanding of the use of Trichoderma asperellum and Streptomyces rochei with shikimic acid-primed seeds as a potential alternative technique for attenuating powdery mildew infection in squash. [ABSTRACT FROM AUTHOR]

Copyright of Menoufia 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.)

Zinc (Zn) and copper (Cu) are essential micronutrients for the plant's growth, development, and metabolism, but in high concentrations, the elements disrupt normal metabolic processes. The present study investigated the effects of different concentrations (added to a Hogland-based solution) of zinc (control, 5, 10 mg L−1 ZnSO4) and copper (control, 0.1, 0.2 mg L−1 CuSO4) on the growth characteristics and biochemical indices of summer squash (Cucurbita pepo L.). Compared with control, a single application of Cu or Zn at both concentrations significantly declined fruit yield, growth traits, pigments content, and high content of these minerals and values of stress-related indices. Increased Cu concentration in the nutritional solutions reduced the activity of ascorbate peroxidase (APX) and guaiacol peroxidase (GPX). Copper at high concentrations intensified ROS production, aggravated oxidative stresses, and decreased the plant yield and productivity. Nonetheless, combining Cu and Zn could alleviate stress intensity by boosting antioxidant enzymes, redox regulation, and a resultant diminishment in the content of H2O2, proline, malondialdehyde, and minerals. The obtained results corroborate that the co-application of zinc in Cu-contaminated areas can improve the plant's economic yield and physiological parameters by hindering copper toxicity and enhancing the photosynthetic capacity. [ABSTRACT FROM AUTHOR]

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]

The squash bug, Anasa tristis (De Geer), is a serious pest of cucurbit crops across the United States, especially within summer squash (Cucurbita pepo L.) systems. Using their piercing sucking mouthparts, squash bugs feed on both leaf tissue and fruits, often leading to leaf necrosis, marketable fruit loss, and even plant death. To date, the relationship between squash bug presence and plasticulture has not been adequately investigated. This 2-yr study evaluated the effects of white, black, and reflective plastic mulch colors on the occurrence of all squash bug life stages and marketable zucchini yield in Virginia. In both years, A. tristis adults and egg masses were more numerous on zucchini plants grown in white and reflective plastic mulch compared to bare ground plants. Greater nymphal densities and marketable fruit yield were observed in certain plastic mulch treatments versus the bare ground treatment, yet these differences were not consistent in both years. Contrary to the repellency effects reflective mulches have on other cucurbit insect pests, our research suggests that reflective and other plastic mulch colors can negatively impact squash bug management, especially in regions with high A. tristis pressure. Our study offers new insights for cucurbit growers to use when considering whether they should implement plasticulture in their growing systems. [ABSTRACT FROM AUTHOR]

Florida (USA) is a major producer of squash, Cucurbita pepo L. (Cucurbitaceae), with approximated 16% of the US production in 2019, valued at about 35 million USD. Major insect pests, including the sweetpotato whitefly MEAM1, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), and the melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), jeopardize plant development and transmit viruses of economic importance that can cause up to 50% yield loss in squash crops. Pesticides are generally used for insect management in squash, but the development of insecticide resistance and their non‐target effects are major concerns. A combination of non‐pesticidal approaches was evaluated, including intercropping flowering plants, augmentation, and conservation biological control to manage key pests in organic squash. Refugia increased natural enemies around the squash; however, only a few beneficial arthropods moved from the companion plants towards the squash plants. Whitefly densities and squash silverleaf ratings were reduced, whereas natural enemies were more abundant when the predatory mite Amblyseius swirskii Athias‐Henriot (Acari: Phytoseiidae) was released alone or together with sweet alyssum, Lobularia maritima (L.) Desv. (Brassicaceae). All companion plants used in this study increased natural enemies, but only African marigolds and sweet alyssum ultimately increased biological control activities. [ABSTRACT FROM AUTHOR]

The plants of summer squash, Cucurbita pepo, are monoecious, bearing their flowers in leaf axils. Plants of C. pepo subsp. pepo, which includes Cocozelle and Zucchini squash, bear one flower per leaf axil whilst plants of C. pepo subsp. texana, which includes Crookneck squash, differentiate two or more flower buds at nearly all leaf axils. This multiple-flowering trait, conferred by the single recessive gene mf, was introgressed from a Crookneck squash (subsp. texana) into several inbreds of Cocozelle and Zucchini squash (subsp. pepo) through six backcross generations. The nearly isogenic hybrids derived from crossing these inbreds, single- and multiple-flowered, were compared with one another in replicated field trials with the purpose of determining whether or not the multiple-flowering trait can significantly increase yields of Cocozelle and Zucchini under field conditions. The results showed that the multiple-flowering trait can increase yield in Cocozelle squash by as much as 60% and in Zucchini squash by 24%. The differences in yield between the respective multiple- and single-flowered hybrids were based on number of fruits produced. The yield differences were most greatly expressed from the end of the first week through the third week of harvest in the Cocozelle and during the third week of harvest in the Zucchini. [ABSTRACT FROM AUTHOR]

Squash (Cucurbita pepo L.) is one of the most commonly cultivated crops in Turkey. In recent years, with the decrease in rainfall and the increase in irrigation costs, there has been an increased interest in edible seed squash cultivation in Turkey, since it can be grown well in arid environments. Virus diseases are the most common problem limiting edible seed squash cultivation in Turkey. During 2017–2019, 625 symptomatic edible seed squash leaves were collected from the fields for detection of pathogenic viruses, including watermelon mosaic potyvirus (WMV), Zucchini yellow mosaic potyvirus (ZYMV), cucurbit aphid-borne yellows polerovirus (CABYV), squash mosaic comovirus (SqMV), cucumber mosaic cucumovirus (CMV), and papaya ringspot potyvirus watermelon strain (PRSV-W) using DAS-ELISA and RT-PCR methods. The calculated relative incidence of viruses infecting plant samples was found to be 88.32%. WMV, ZYMV, and CABYV were identified as the most prevalent viruses with the relative incidences of 56.96, 56, and 20.16%, respectively. CMV (1.12%), PRSV-W (0.48%), and SqMV (0.32%) were the least commonly detected viruses in samples. The 24 selected isolates of CMV (2), WMV (12), ZYMV (6), and CABYV (4) were sequenced and deposited in the GenBank database. The phylogenetic analysis revealed that Turkish isolates of these viruses belong to the same clusters in phylogenetic trees and generally showed high similarities to the isolates of neighboring countries. Moreover, except for the CABYV isolates, the sequence diversity among the isolates was generally very low. It is thought that the knowledge gained from observations of this study will be useful to beneficiaries as it provides a basis for further research into the breeding programs of squash varieties resistant to virus diseases. [ABSTRACT FROM AUTHOR]

Background: Summer squash (Cucurbita pepo: Cucurbitaceae) are a popular horticultural crop for which there is insufficient genomic and transcriptomic information. Gene expression atlases are crucial for the identification of genes expressed in different tissues at various plant developmental stages. Here, we present the first comprehensive gene expression atlas for a summer squash cultivar, including transcripts obtained from seeds, shoots, leaf stem, young and developed leaves, male and female flowers, fruits of seven developmental stages, as well as primary and lateral roots. Results: In total, 27,868 genes and 2352 novel transcripts were annotated from these 16 tissues, with over 18,000 genes common to all tissue groups. Of these, 3812 were identified as housekeeping genes, half of which assigned to known gene ontologies. Flowers, seeds, and young fruits had the largest number of specific genes, whilst intermediate-age fruits the fewest. There also were genes that were differentially expressed in the various tissues, the male flower being the tissue with the most differentially expressed genes in pair-wise comparisons with the remaining tissues, and the leaf stem the least. The largest expression change during fruit development was early on, from female flower to fruit two days after pollination. A weighted correlation network analysis performed on the global gene expression dataset assigned 25,413 genes to 24 coexpression groups, and some of these groups exhibited strong tissue specificity. Conclusions: These findings enrich our understanding about the transcriptomic events associated with summer squash development and ripening. This comprehensive gene expression atlas is expected not only to provide a global view of gene expression patterns in all major tissues in C. pepo but to also serve as a valuable resource for functional genomics and gene discovery in Cucurbitaceae. [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]

Summer squash is a vegetable of significant acceptance in the market due to its economic and nutritional importance, with the potential for expansion in the food industry. In this context, this study aimed to evaluate the gas exchange and growth of summer squash plants subjected to a saline nutrient solution and exogenous application of hydrogen peroxide. The study was conducted in a greenhouse in Pombal - PB. The cultivation system used was the Nutrient Film Technique (NFT) hydroponic system. The experimental design was completely randomized, in a 4 x 4 factorial arrangement, whose treatments consisted of four levels of electrical conductivity of the nutrient solution - ECns (2.1, 3.1, 4.1, and 5.1 dS m-1) and four concentrations of hydrogen peroxide - H2O2 (0, 20, 40, and 60 µM), with three replications. The increase in the nutrient solution salinity from 2.1 dS m-1 reduced the leaf area and transpiration of the summer squash plants. Hydrogen peroxide at a concentration of 40 µM increased the root length, the instantaneous carboxylation efficiency, and the CO2 assimilation rate when the plants were subjected to the saline solution of 2.1 dS m-1. Also, the application of 60 µM H2O2 mitigated the effect of salt stress on the internal CO2 concentration and stomatal conductance of the summer squash plants. [ABSTRACT FROM AUTHOR]

In this study, the effects of 1-methylcyclopropene (1-MCP) treatment on the antioxidant enzymes and fruit quality parameters of baby squash (Cucurbita pepo L., cv. Soleil F1 and İskender F1) during cold storage was investigated. After being freshly harvested, the İskender F1 (green-skinned) and Soleil F1 (yellow-skinned) baby squash were treated with 250 and 500 ppb concentrations of 1-MCP and stored at 10 °C for 14 days. The 250 ppb 1-MCP treatment suppressed the loss of total soluble solid, ascorbic acid, total phenolic, and total flavonoid contents during storage in the Soleil F1 squash. Similarly, the 250 ppb 1-MCP treatment delayed the loss of ascorbic acids and titratable acidity of İskender F1 squash. The highest ascorbic acid content and antioxidant activity were determined with the 250 ppb 1-MCP treatment, while the highest total chlorophyll content was detected in the 500 ppb 1-MCP-treated İskender F1 squash. The initiation of fruit softening and chlorophyll degradation was delayed in the 1-MCP-treated squash. Ethylene emission was also inhibited by the 1-MCP treatments in both types of squash. 1-MCP treatment effectively reduced the weight loss and decay incidence in both squash cultivars. The results indicated that the 250 ppb 1-MCP treatment retained antioxidant enzymes for a longer period and it was found to be more effective for maintaining the fruit quality parameters of the cold-stored baby Soleil F1 and İskender F1 squash. [ABSTRACT FROM AUTHOR]

Copyright of Yuzuncu Yil Universitesi Journal of Agricultural Sciences (YYU J Agr Sci) is the property of Yuzuncu Yil 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.)

Cucurbita pepo contains a wealth of genetic variability in fruit size, shape, and color. A common fruit color pattern in C. pepo is striping of the fruits. Stripes occur on the fruit exterior in accordance with the positions of the 10 main subepidermal vein tracts, and can be normal, with darker stripes occurring between and lighter stripes over and adjacent to the vein tracts, or reversed, with lighter stripes occurring between and darker stripes over and adjacent to the vein tracts. Reverse striping has been reported as being independent and at other times dependent on the presence of the dominant allele for dark stem color, D. The objective of this investigation was to determine the relationship, if any, between the two types of reverse striping, dark-stem-dependent and independent. For this purpose, two accessions, which when crossed produced progeny having dark-stem-dependent reverse striping, were crossed with seven near-isogenic tester accessions of known genotype. The results indicated that the two types of reverse striping are conferred by different alleles at the same locus, which is also the same locus at which other alleles confer normal striping. The results of crossing among the nine accessions suggest that two genes reported as having major effects on fruit color, l-2 and W, are actually the same locus (or two tightly linked loci). To minimize possible confusion, it is suggested that this multiple-allelic locus be hereafter referred to as l-2. This locus has seven alleles, of which the two top dominants, L-2WS and L-2W, and the bottom recessive, l-2, confer the exact same fruit phenotype, weak coloration. Two intermediate alleles, L-2 and L-2i, result in intense fruit coloration and normal striping, and two other intermediate alleles, L-2Wr and l-2R, respectively, confer dark-stem-dependent and independent reverse striping. The order of dominance of the seven alleles is L-2WS > L-2W > L-2Wr > L-2 > L-2i > l-2R > l-2. [ABSTRACT FROM AUTHOR]

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.)

Two experiments were carried out in the autumn season of 2018 and spring season of 2019 respectively. The aim of the current study was to investigate the effect of spraying individual and combination of amino acids and nano-boron on the viability and vigor of the seed of summer squash (Cucurbita pepo L.). The treatments were sprayed with different concentrations of amino acids (0, 1.5 and 3 mL. L-1) symbolized as (A0, A1 and A2), respectively and different concentrations of the nano-boron (0, 4 and 8 mg. L-1) as named (B0, B1 and B2) respectively. The results demonstrated that, the treatment (A2) was significantly superior in all studied experimental indicators compared to the control treatment. Also, the B2 treatment was outperformed in the indicators of the viability and vigor of the seed for both autumn and spring seasons. The bilateral interaction between amino acids and Nano-boron (A2 and B2) was significantly superior in all experimental indicators which represent qualitative characteristics of the seed as compared with the control treatment for both autumn and spring seasons. In conclusion, spraying summer squash with combination of amino acids and nano-boron improved the viability and vigor of the seed in both autumn and spring seasons. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate efficiency sticky traps on attraction Bemisia tabaci (Gennadius) on squash plants Cucurbita pepo L. (three squash varieties i.e. Arkan, Sama 740 and Andro 174) under greenhouse conditions at Perkash (Giza governorate) during 2017, 2018 seasons. This study contains three experiments, The first experiment aimed to evaluate the efficiency color of the sticky trap on attraction B. tabaci through comparison between four colors (yellow, blue, red and white). This experiment was carried out on squash plants during the period (February - March). Results showed that the traps which have yellow color more efficiency than others which have (blue, red, and white) color, respectively. The second experiment aimed to evaluate the efficiency height of the yellow sticky trap on attraction B. tabaci through comparison between four heights (2m, 1.5m, 1m and 0.5m) above the ground. And this experiment was carried out on squash plants during the period (April - May). Results showed that the trap which has 2m height above the ground more efficiency than others which have (1.5m, 1m and 0.5m) heights, respectively. The third experiment aimed to evaluation efficiency orientation of the yellow sticky trap on attraction B. tabaci through comparison between four orientations (North, South, East and West). And this experiment was carried out on squash plants during the period (June - July). Results showed that had no clear effect of the trap orientation on attraction B. tabaci. [ABSTRACT FROM AUTHOR]

A field experiment was conducted during the autumn season 2017 at one of the fields in Al-Hamdaniya area of the Abu-Ghraib district 15 km west of Baghdad, in a salty clay loam texture soil. To study the effect interaction of three levels of additionpotassium0, 75 and 150 kg.h-1 (K1, K2 and K3) respectively and mixture of ( humic and fulvic) acids, 0, 250 and 500 mg l -1 (H0, H1 and H2) respectively, on some growth and yield characteristics of squash zucchini Cucurbita pepo L. A randomized complete block design (RCBD) with Split Plot distribution with three replications was used. The levels of addition potassium occupied the main plots. The mixture of acids levels were occupied sub plots, the most important results that have been obtained, Increasing of additionpotassium as K2, K3 resulted in a significant increasing in some traits under study (dry weight of shoot, total soluble sugars concentration, proline concentration, fertilizer use efficiency, Concentration N, P, K comparison with K1. Also the high addition potassium (K1, K2) caused a significant increasing in fertilizer use efficiency (43.00, 52.07%) respectively comparison with K0 (3.94%), increasing of addition potassium as K2 resulted in a significant increasing in some traits under study (Plant length, leaf area, number of fruits comparison with K0, K1. Also the high addition potassium (K2) caused a significant increasing in total yield 22.83 ton.ha-1 comparison with K0, K1 (15.70, 20.43ton.ha-1). Also the high addition potassium (K2) caused a significant increasing in respectively N, P, K. Increasing of humic and fulvic acids as levels H2, H3 resulted in a significant increasing in some traits under study (Plant length, leaf area, number of fruits, comparison with H0. Also the high level (H2) caused a significant increasing in total yield 20.02 ton.ha-1 respectively comparison with H0 (19.26 ton.ha-1). Also, the high (H2) caused a significant increasing in respectively N, P, K. The interaction between of the study factors were significant at most of measurement characteristics. The treatment K2XH2 gave the highest value in total yield (23.50 ton.ha-1) comparison with K0XH0 (14.84 ton.ha-1). [ABSTRACT FROM AUTHOR]

This study was aimed to investigate,growth,yield and phytosterol of squash (Cucurbita pepo L. , medical pumpkin (Cucurbita pepo subsp.) and thier hybrids.The study included crossing among 15 pure lines of squash and medical pumpkin . pepo var. styriaca during fall season 2013 at greenhouse during spring 2014 the genotypes of the Department of Horticulture and Landscape Gardening, College of Agriculture, University of Baghdad. The genotypes (medical pumpkin ST + 9 parents of squash, crosses with medical pumpkin + 11 specific hybrid) were planted at the open field. The layout of the experiment was completely randomized block design. The results showed significant differences among genotypes in the studied traits. The parents ST, E1, E3, E6, K3 and K7 showed superiority when compared to other parents in vegetative and flowering growth, earliness of maturity, yield and phytosterol. Hybrids ST1 × E, H × ST1, K × ST3, K7 × ST, E6 × ST and MR × ST were significantly superiored to other hybrids in the studied characters and had highest positive and significant hybrid vigor. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Horticultura is the property of Universidad Autonoma Chapingo 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.)

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]

Cucurbits (Cucurbitaceae family) consist of 119 genera and 825 species and are cultivated worldwide, especially in tropical and subtropical regions. In the world, squash (Cucurbita pepo L.), watermelon (Citrullus lanatus (Thunb) Matsum&Nakai), cucumber (Cucumis sativus L.), and melon (C. melo L.) are the most cultivated cucurbit species as vegetable crops. Squash is grown for fresh consuming, as well as its seeds are used like a snack in Turkey. Viruses are one of the most destructive pathogen groups on squash which is grown for seeds in Yozgat province. In this study, it was aimed to determine the virus infections in economically important squash planting fields in the province. Totally 140 plant samples which show widespread virus symptoms such as mottling, shoe-string, mosaic, stunting, curling, vine decline, distortion, and blistering were collected from plants in 2017. In this study, DAS-ELISA method is used for identifying the virus infections on the plant samples. According to the results of the DAS-ELISA 84.28 % of plant samples were infected with Cucumber mosaic cucumovirus (CMV), Watermelon mosaic potyvirus (WMV), Papaya ring spot potyvirus-watermelon strain (PRSV-W), Zucchini yellow mosaic potyvirus (ZYMV), and Squash mosaic comovirus (SqMV). The prevalent virus was WMV with the ratio of 57.85 %. It was followed by ZYMV which was detected on the samples at the ratio of 53.57 %. Besides, double and multiple virus infections were determined commonly in the samples. Especially, ZYMV+WMV mixed infections were common. The infection of Cucumber green mottle mosaic tobamovirus (CGMMV) wasn't determined in the survey area. [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]

During 2016-2017, growers at San Juan de Los Planes, El Carrizal, and El Pescadero at Baja California Sur, Mexico experienced serious outbreaks of phytoplasma squash yellowing disease, causing significant economic loss, mostly from low yield and quality of squash, Cucurbita pepo L., for export. In addition, abundant beet leafhoppers, Circulifer tenellus (Baker), presumed to transmit the disease, were observed in each field. Using nested-polymerase chain reaction (PCR) amplification of the 16S rRNA gene and comparing in silico patterns, positive Western X-disease phytoplasma of the 16SrIII group was detected. Scanning electron microscopy showed phytoplasmatic particles in sieve tubes of infected plants and insects. Phytoplasma risk based on combined data of insect abundance, disease incidence, and economic threshold was analyzed to evaluate the impact of the disease over time. Only at Los Planes with 128 adult insects per trap and 75.5% incidence of disease was risk of phytoplasma high, while at El Carrizal and El Pescadero, risk was moderate. This is the first evidence of beet leafhoppers transmitting phytoplasma to squash at Baja California Sur. The information will be useful for managing disease in the region and where squash is grown worldwide. [ABSTRACT FROM AUTHOR]

Copyright of Yuzuncu Yil Universitesi Journal of Agricultural Sciences (YYU J Agr Sci) is the property of Yuzuncu Yil 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.)

Copyright of Menoufia 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.)

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.)

Two field experiments study during 2015 and 2016 summer seasons on sandy loam soil under drip irrigation system by Nile river water, at the Agricultural Research and Production Station National Research Centre, El-Nubaria region, ELBeheira Governorate, Egypt. This study focused on the applications of different water deficiency levels (100%, 80% and 60% of F.C. i.e. field capacity) and ascorbic acid (AsA) spraying foliar application with different concentrations (0, 50 and 100 ppm) as antioxidant on growth parameters and yield as well as photosynthetic pigments content of summer squash plants (Cucurbitapepo L.cv. Eskandrani). Results indicated that, decreasing water levels caused a significant reduction in the all tested growth and yield parameters, i.e., canopy weight, root weight, number of leaves, leaves fresh weight and leaf area as well as photosynthetic pigments content (total chl., and carotenoids), total yield, fruit weight and length. While increasing ascorbic acid spraying foliar application levels as antioxidant significantly increased the aforementioned parameters in the two seasons as compared with control. On the other hand, decreasing water levels caused a significant increasing in leaf proline content, leaf cell sap osmotic pressure, dry matter % and fruit TSS in the two growing seasons as compared with control. [ABSTRACT FROM AUTHOR]

Root and crown rot incited by Phytophthora capsici causes considerable annual losses in squash-producing regions in the United States. 'Spineless Perfection' zucchini and 'Cougar' straightneck squash (Cucurbita pepo L.), partially resistant and susceptible to root and crown rot, respectively, were investigated for differences in root and crown physical factors and the histology of crown infection by P. capsici. The pH and titratable acidity of healthy root and crown tissue from tissue extracts were not significantly different between cultivars (P = 0.05). Crude fiber content (%) of blended and oven-dried root and crown tissue from healthy plants was similar between cultivars. However, dry matter (%) was highest for Cougar (P = 0.05). Colonies of P. capsici grown from mycelial plugs in root exudates collected from each cultivar were similar in diameter. Whole mounts and histological sections of healthy and infected crown tissue revealed that vascular bundles and metaxylem vessels were more abundant in crowns of Spineless Perfection than Cougar. Twelve to 48 h post inoculation (hpi), mycelia in the crown of each cultivar was limited to the cortex and hypodermal tissue. By 72 hpi, hyphae were observed in the cortex and endodermal tissue of Cougar and were concentrated in the phloem and parenchyma cells surrounding vascular bundles. Mycelia were limited to the outer cortex in Spineless Perfection. Mycelia and occluding material were present in the majority of metaxylem vessels of Cougar but not Spineless Perfection at 92 hpi; dissolution of parenchyma cells surrounding vascular bundles was apparent in Cougar. The vascular occlusions observed in Cougar may be responsible for plant wilting, a common disease symptom. Additional straightneck, crookneck, scallop, and acorn squash (C. pepo ssp. ovifera), and zucchini, marrow, and pumpkin (C. pepo ssp. pepo) cultivars were evaluated in a greenhouse study for resistance to root and crown rot. Cucurbita pepo ssp. ovifera cultivars were significantly more susceptible than C. pepo ssp. pepo to root and crown rot (P < 0.0001). Growing C. pepo ssp. pepo cultivars may be beneficial in an integrated Phytophthora management program. [ABSTRACT FROM AUTHOR]

• Nano-K maximized salt-stressed squash plant productivity and yield quality. • Nano-K catalyzed more antioxidant activities, attenuating damage of oxidative stress markers. • Nano-K efficiently improved photosynthesis and plant integrity under salt stress. • Nano-K efficiently restored the nutrients of salt-stressed squash plants. • Nano-K efficiently improved antioxidant enzymes and their gene expression in salt - stressed squash plants. To explore the reinforcing effects of nano-potassium fertilizer (nano-K) on growth, yield and quality, physio-biochemical responses, antioxidant defense systems, antioxidant gene expressions, and nutrients of salt-stressed squash plants, field experiments were performed using normal (EC = 2.34 dS m−1) and saline (EC = 9.38 dS m−1) soils during the 2021 and 2022 seasons. The traditional recommended K at full dose (TRK 100) or half dose (TRK 50) was used in both soils. Salinity and/or TRK 50 significantly decreased photosynthetic pigment contents (by 8.7−22.5%), photosynthetic efficiency (by 6.0−10.9%), relative water content (RWC by 5.0−5.1%), membrane stability index (MSI by 7.2−7.4%), nutrient contents (by 28.4−48.2%), K+/Na+ ratio (by 66.4−67.1%), which contributed to the decrease in growth (by 12.2−25.8%) and yield traits (by 4.2−28.5%), and fruit quality (by 8.5−19.7%) due to an increment of oxidative stress biomarker (O 2 •‒ by 32.4−52.9% and H 2 O 2 30.4−57.1%) levels, electrolyte leakage (EL by 23.3−24.5%), malondialdehyde (MDA by 71.4−77.6%), and Na+ (by 55.5−56.9%). Under stress in both soils, foliar-applied 0.50 g nano-K L−1 suppressed the levels of O 2 •‒, H 2 O 2 , MDA, EL, and Na+, while noticeably increased photosynthetic pigment contents, photosynthetic efficiency, RWC, MSI, nutrient contents, K+/Na+ ratio, which were positively reflected in growth and yield traits, and fruit quality due to increased osmoprotectant and low-molecular-weight antioxidant contents, antioxidant enzyme activities and enzymatic gene expressions. Therefore, our findings recommend using nano-K as an effective strategy to promote antioxidant and photosynthetic machineries, minimize oxidative stress biomarkers and Na+ levels, boost tolerance to salt stress, and improve squash yield and yield quality under salt stress. Shows the reinforcing effect of nano-K on the antioxidant defense system reflecting the increased yield and quality of salt-stressed squash plants [Display omitted] [ABSTRACT FROM AUTHOR]

The current study describes the effect of coloured plastic mulch, clear and black polyethylene (PE), on growth and productivity of different summer squash varieties grown on February “off-season”. A field experiment was carried out during 2012 and 2013 seasons at the Experimental Farm of Faculty of Agriculture, Assiut University, Assiut, Egypt. The performance of different parameters studied for plant received different mulch treatments was superior to the control (bare soil) treatment. The genotypic differences among squash varieties investigated were found significant for all the studied parameters. Clear PE mulch was significantly more effective than the black PE mulch in this respect. Plants of cvs sown on clear PE flowered earlier than those sown on black PE or bare soil.Total fruit yield (ton/fed) was significantly increased by using clear PE (total fruit yield was 12.61 and 12.94 ton/fed in the 1 st and 2 nd seasons, respectively; corresponding values for the bare soil were 7.61 and 7.74 ton/fed). Plants of ‘Eskandrany' produced using clear PE were significantly the earliest to flower and gave the highest early and total fruit yield. It is concluded that mulching, especially clear PE, can be usefully utilized to enhance the summer squash production when grown off-season. [ABSTRACT FROM AUTHOR]

• Background and Aims Summer squash, the young fruits of Cucurbita pepo, are a common, high-value fruit vegetable. Of the summer squash, the zucchini, C. pepo subsp. pepo Zucchini Group, is by far the most cosmopolitan. The zucchini is easily distinguished from other summer squash by its uniformly cylindrical shape and intense colour. The zucchini is a relatively new cultivar-group of C. pepo, the earliest known evidence for its existence having been a description in a book on horticulture published in Milan in 1901. For this study, Italian-language books on agriculture and cookery dating from the 16th to 19th centuries have been collected and searched in an effort to follow the horticultural development and culinary use of young Cucurbita fruits in Italy. • Findings The results indicate that Cucurbita fruits, both young and mature, entered Italian kitchens by the mid-16th century. A half-century later, round and elongate young fruits of C. pepo were addressed as separate cookery items and the latter had largely replaced the centuries-old culinary use of young, elongate bottle gourds, Lagenaria siceraria. Allusion to a particular, extant cultivar of the longest fruited C. pepo, the Cocozelle Group, dates to 1811 and derives from the environs of Naples. The Italian diminutive word zucchini arose by the beginning of the 19th century in Tuscany and referred to small, mature, desiccated bottle gourds used as containers to store tobacco. By the 1840s, the Tuscan word zucchini was appropriated to young, primarily elongate fruits of C. pepo. The Zucchini Group traces its origins to the environs of Milan, perhaps as early as 1850. The word zucchini and the horticultural product zucchini arose contemporaneously but independently. The results confirm that the Zucchini Group is the youngest of the four cultivar-groups of C. pepo subsp. pepo but it emerged approximately a half-century earlier than previously known. [ABSTRACT FROM AUTHOR]

Rehydration typically composes of three simultaneous processes: the imbibition of water into dried material, the swelling of the rehydrated products and the leaching of soluble solids to rehydration medium. In this research, squash (Cucurbita pepo) fruits were cut into 0.4 cm thick and 4 cm diameter slices. Then, squash slices were blanched in a steam chamber for 4 min. After cooling to room temperature, squash slices were dehydrated up to moisture content of 0.1065 kg H2O per kg d.m. Dehydrated samples were stored at 4°C. Squash slices with specified weight were rehydrated by immersion in distilled water at different temperatures (25, 50, and 75°C), various dry matter-water ratios (1:25, 1:50, and 1:100), which was agitated at 100 rpm. At specified time intervals, up to 300 min, the squash samples were removed from the water, and the weight, moisture content and rehydration indices of the sample were determined. The texture characteristics were examined over a 180 min period. The results showed that moisture content, water absorption capacity (WAC) and rehydration ability (RA) of squash slices increased, whereas dry matter holding capacity (DHC) and texture firmness (maximum force and stress) decreased with rehydration time. The maximum WAC was achieved in squash slices rehydrated into 75°C water at 1:100 dry matter-water ratio. The lowest force and stress were observed in squash slices which were rehydrated into 75°C water after 180 minute. These squash slices had the maximum moisture content and RA and the minimum DHC. The lowest moisture content and RA and the highest DHC, force and stress, were observed in squash slices immersed in water at 1:100 dry matter-water ratio. In general, for all rehydration conditions of squash slices, the highest water absorption rate occurred during the first minuts of process. Then, this rate decreased. The highest rehydration rate and amount of water absorption occurred in 75°C. [ABSTRACT FROM AUTHOR]