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Honeydew melon has grown in popularity because of its nice odour and sweet flavours. This advocated using enzyme to hydrolyse the honeydew melon and then spray drying it into powder. Two parameters were manipulated: maltodextrin concentrations (10–50% w/w) and inlet temperatures (140–180 °C). The spray-dried honeydew melon powders were examined for process yield, water activity, moisture content, hygroscopicity, bulk density, solubility and colour. The reconstituted powders were assessed by determining TSS, pH, viscosity and colour. The results indicated that the greater maltodextrin concentration employed resulted in a significantly (p ≤ 0.05) lower moisture content and hygroscopicity, as well as a significantly (p ≤ 0.05) higher powder solubility. The 20% maltodextrin concentration was optimum due to the optimal process yield (64.09 ± 5.26%) was obtained. Water activity and moisture content had decreased due to the rise in inlet temperature. The inlet temperature, 170 °C was selected as optimum inlet temperature due to higher process yield (69.83 ± 10.63%) and highest solubility (107.67 ± 6.11 s/g) of spray-dried honeydew melon powder. Overall, there were no significant difference (p > 0.05) in the properties of optimised reconstituted honeydew melon powder with the initial juice, except L* and b* values. In short, the production of enzyme-hydrolysed honeydew melon powder was feasible, which could widen its applicability in food industry.

This study aimed to investigate the effect of replacing corn starch in the standard diet of diabetic hypercholesterolemic rats with 3, 6 and 9% levels of honeydew melon fruit powder, peeled honeydew melon fruit powder and honeydew melon peels powder (melon fractions) on the body weight gain, insulin, organs weight, blood glucose, total cholesterol, LDL, triglyceride, kidney functions, liver functions, catalase enzyme, glutathione S-transferase enzyme and malondialdehyde. Data showed diabetes and hypercholesterolemia caused a significant increase in body weight gain, organs weight, blood glucose, total cholesterol, LDL, triglyceride, kidney functions, liver functions and malondialdehyde as well as a significant decrease in insulin, catalase enzyme and glutathione S-transferase enzyme of rats. The feeding with any level of melon fractions restored the normal liver weight and AST level in diabetic hypercholesterolemic rats to the normal values in negative control rats. Also, feeding with 9% melon fractions restored the normal body weight gain, insulin, kidney weight, heart weight, urea, creatinine, ALT, catalase enzyme, glutathione S-transferase enzyme and malondialdehyde in diabetic hypercholesterolemic rats to the normal values in negative control rats. Although glucose, total cholesterol, LDL, triglyceride, and ALP in diabetic hypercholesterolemic rats were decreased by increasing the melon fraction levels but did not return to normal values in negative control rats. [ABSTRACT FROM AUTHOR]

To reduce freezing-induced damage, a novel freezing method based on pressurized CO 2 pre-injection combined with ultrasound-assistance was developed for quick freezing of pieces of honeydew melon. The samples were first exposed to CO 2 at different pressures (0.2 MPa, 0.5 MPa and 0.8 MPa) and then placed in an ultrasound-assisted freezing device. The ultrasonic intensity was 0.15 W/cm2 at 20 kHz. The results indicate that pre-injection of CO 2 enhanced ultrasonic cavitation and significantly (p < 0.05) increased the nucleation temperature, thus shortening the freezing time. CO 2 combined with ultrasonic assisted freezing can reduce the variation in the state of water in the sample after freezing and thawing. The results of SEM, cryo-microscopy and inverted fluorescence microscopic observations show that the cellular structure of the sample was better protected and the tissue was less damaged by ice crystals. This suggests that CO 2 pre-injection combined with ultrasound assist during freezing can effectively control ice nucleation, ice crystal growth and reduce freezing-induced damage. [ABSTRACT FROM AUTHOR]

Honeydew is a sugar-rich food source produced by sap-feeding insects, notably by major pests such as aphids and whiteflies. It is an important alternative food source for the adult stage of various key natural enemies (e.g., parasitoids), but it may be used also as food by agricultural pests. Necremnus tutae is an idiobiont parasitoid, and it is the most abundant larval parasitoid associated with the South American tomato pinworm, Tuta absoluta, in recently invaded European areas. The impact of N. tutae on T. absoluta populations was evaluated under greenhouse conditions with and without the presence of a honeydew producer, the aphid Macrosiphum euphorbiae. In addition, laboratory experiments were performed to evaluate the longevity of N. tutae and T. absoluta adults when fed with water, honey or honeydew produced by the aphid. In the greenhouse, N. tutae effectively reduced T. absoluta population by the end of the experiment, and this independently of the presence of the aphid; still the presence of M. euphorbiae led to delayed and reduced T. absoluta population peak when controlled by the parasitoid (there was a fourfold increase in parasitoid density in presence of aphid). The longevity of both N. tutae and T. absoluta females increased in the presence of honeydew (when compared to water only) under laboratory conditions; it hinted that honeydew could be used by an herbivore as T. absoluta. The interactions between the two phytophagous species showed contrasting effects, and this mostly independently of parasitoid presence. Tuta absoluta had no impact on aphid population dynamics. By contrast, the production of T. absoluta larvae was higher in the first part of the experiment as the adults lived longer (feeding on aphid honeydew) and produced more larvae. In the second part of the experiment, there were fewer T. absoluta larvae in the presence of the aphid, likely owing to resource competition and/or negative plant-mediated indirect interactions. We demonstrated that honeydew producers could impact parasitoid-host population dynamics both through direct and indirect interactions and that potential positive effects of a sugar food source toward a pest can be nullified in the long term by other negative effects occurring simultaneously. [ABSTRACT FROM AUTHOR]

An oscillating magnetic field (OMF) was used to extend the supercooled state in honeydew melon samples. The internal temperature of the samples under OMF treatment was kept at -5.5°C during a 21-day storage period without freezing. To inhibit ice crystal nucleation, the OMF treatment was controlled using a repeated sequence of on/off cycles with durations of 120/420 s. Quality factors of the supercooled samples were measured and compared with fresh, refrigerated, and frozen samples. Factors such as microbiological analysis, drip loss, pH, titratable acidity, and soluble solids contents indicated that the overall quality of the supercooled samples after 21 days was not significantly different (p > 0.05) from that of fresh samples. Although a few cells in the supercooled samples had undulated walls compared to fresh samples under microscopic analysis, the cells were closely bonded to each other, and distorted cells were not found. [ABSTRACT FROM AUTHOR]

Challenges in cultivar selection and availability has inhibited the expansion of the organic melon market. This study evaluated the sensory and physicochemical properties of four organically grown melon cultivars over a two-year period at three growing locations; two honeydew cultivars: ‘Dulce Nectar’ and ‘Jaune’, and two cantaloupe cultivars: ‘Athena’ and ‘Sivan’. Trained and consumer panels evaluated 17 sensory attributes, including appearance, texture, flavor, and overall acceptance. Physicochemical measurements included flesh color, texture, pH, soluble solids content (SSC), and titratable acidity (TA). Results showed that ‘Sivan’ and ‘Athena’ were preferred by panelists for their flavor and overall eating quality; these cultivars also had relatively high SSC, high pH, and low TA. Conversely, ‘Jaune’ was the least preferred, with higher intensities of ‘veggie’ and ‘green’ flavors; this cultivar also had relatively low pH and high TA. Overall, ‘Sivan’ performed consistently better than all other cultivars both years, scoring highest in positive attributes, such as ‘sweetness’ and ‘juiciness’. This research can be used to support the organic melon industry in cultivar selection. [ABSTRACT FROM AUTHOR]

• Liquid CO 2 spray freezing technology was applied to freeze honeydew melon. • Static magnetic fields were used to improve the freezing process of liquid CO 2. • The nucleation process and quality of frozen melon was significantly improved. • The static magnetic field of 15 mT strength suggested the best results. The effectiveness of static magnetic fields with different intensities (5, 10, 15 mT) combined with liquid carbon dioxide spray freezing (LCSF) technique in improving the quality of frozen honeydew melon was investigated. The results showed that LCSF with magnetic fields above 10 mT significantly improved ice nucleation and quality of frozen melons compared to conventional −20 °C freezing, −80 °C freezing and LCSF method without magnetic field assistance (P < 0.05). 15 mT strength static magnetic field assistance suggested the best results, with a 15.0% reduction in total freezing time, 17.7% increase in average freezing rate, 26.6% reduction in drip loss, and better maintenance of sample quality compared to LCSF. These findings demonstrate that LCSF with static magnetic field assistance is promising in improving the quality of frozen foods. [ABSTRACT FROM AUTHOR]

An experiment was conducted to determine the possibility of using organic materials for the honeydew melon seedling production. Honeydew melon was grown in nine media with different rates of spent mushroom substrate (SMS), vermicompost (VC), cattle manure compost (CaMC), and coconut fiber (CF). Element sulfur was also added to mixtures at a rate of 1.0 g kg−1substrate. The experiment was arranged in a randomized complete block design with three replications. The results determined that all media had desirable physical properties. At the same rates of SMS and VC, CF supported better growth of seedling than CaMC. Seedlings treated with CF had higher morphological growth parameters. It is suggested that CF should be used as an additive for media of SMS and VC. The study clearly indicated that the growing medium with 50% SMS, 30% VC, and 20% CF gave the best condition for honeydew melon seedlings. [ABSTRACT FROM PUBLISHER]

Cucurbit yellow stunting disorder virus (CYSDV), emerged in the Sonoran Desert region of the southwestern USA in 2006 and has become well established. Symptoms induced by CYSDV infection include a striking interveinal chlorosis or yellowing and reduced yield and quality. The virus is transmitted by Bemisia tabaci, and the cryptic species MEAM1 has been present in the region since the early 1990s. CYSDV has now become the most economically important of the viruses affecting cucurbit production in the southwestern US. Here, we present a review of recent studies on CYSDV in the southwestern US, with implications for management of this virus throughout the world. Field surveys have established that CYSDV results in late-season infection of spring melon crops with limited economic impact; however, all summer and fall cucurbits become infected shortly after emergence due to high B. tabaci populations and abundant sources of inoculum. Studies have also demonstrated that CYSDV has an extensive host range among crops and weeds prevalent in the region. Recent studies demonstrated considerable variation in virus accumulation and transmission rates among the host plants evaluated as potential reservoirs. Cucurbit hosts had the highest CYSDV titers, were efficient sources for virus acquisition, and showed a positive correlation between titer in source plants and transmission to cucurbit plants. Non-cucurbit hosts had significantly lower CYSDV titers and varied in their capacity to serve as sources for transmission. Experiments demonstrated that multiple factors influence the efficiency with which a host plant species will be a reservoir for vector transmission of CYSDV to crops. Melon PI 313970 was identified as a new source of host plant resistance to CYSDV, in addition to the previously identified TGR 1551 (=PI 482420) and TGR 1937 (=PI 482431). Potential new sources of CYSDV resistance were identified by field screening of ca. 500 melon accessions with naturally occurring inoculum from 2007 through 2012. Host plant resistance to B. tabaci has also been identified in melon germplasm resistant to CYSDV and could be an important factor in reducing losses to CYSDV. Resistance to CYSDV is being transferred to US western shipping type cantaloupe and honeydew. [ABSTRACT FROM AUTHOR]

Background Honey is classified in blossom honey (nectar of plants) or honeydew honey (secretions of living parts of plants or excretions of plant-sucking insects on plants). The antioxidant and antibacterial properties of honeydew honey are higher than those of most blossom honeys. Scope and approach Therefore it is important to determine the kind of honey to avoid adulterations. In this work, studies carried out to differentiate honeys according their botanical origin (blossom or honeydew) have been reviewed. Key findings and conclusions Honeydew honey is generally characterized by higher values of electric conductivity, pH, acidity and ash content, darker colour, higher oligosaccharides content and lower content of monosaccharides than blossom honey. FT-NIR and FT-MIR spectroscopy have been proposed for the honey authentication. These techniques also allowed the simultaneous determination of sugars and physicochemical parameters used in routine quality control of honey. The trisaccharide melezitose was regarded as a characteristic feature of honeydew honey. A diacylglycerilether was identified as a biochemical marker for honeydew honey. As conclusion, nowadays frauds can be avoid because honeydew and blossom honeys can be classified correctly. [ABSTRACT FROM AUTHOR]

In the present work, 6 honeydew samples of known geographical and botanical origins and 11 honeybee samples were analyzed to detect possible contamination by the thermoelectric power plants in Mugla, Turkey. The contents of trace elements were determined by atomic absorption spectrometry after application of microwave digestion. The samples from the thermal power plants, which were 10–22 km away from the hives, that did not cause pollution in honeydew honeys were also analyzed. The levels of copper, cadmium (Cd), lead (Pb), zinc, manganese, iron, chromium, nickel, and aluminum were similar to the values found in other recent studies in literature. However, it was found that the contamination levels of the toxic elements such as Pb and Cd in honeybee samples measured relatively higher than that of honey samples. The study concludes that honeybees may be better bioindicators of heavy metal pollution than honey. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate effects of spent mushroom substrate (SMS) and chicken manure compost (ChMC) on growth, yield, and fruit quality of honeydew melon and to determine the most suitable rate of SMS for honeydew melon production. Honeydew melon seedlings grown in four different rates of SMS were planted in the net house with two different organic material rates (M1, M2). The experiment was arranged in a split-plot design. The results showed that increasing of organic materials in the net house increased growth, yield, and quality of honeydew melon, due to enhancing of pH, organic matter (OM,) and the nutrient concentrations in the soil. However, growing media with 40 % SMS + 60 % ChMC in the nursery period and the rate of 10 tons SMS + 10 tons ChMC ha−1in the net house period gave the best yield and fruit quality of honeydew melon. [ABSTRACT FROM PUBLISHER]

Effects of chitosan, calcium chloride, and their combination on preventing quality and safety deterioration of postharvest fresh-cut honeydew melon at 7 °C were investigated. Treatments of all these three delayed weight loss, improved firmness, delayed colour changes and moderately inhibited microbial growth. Interestingly, combined treatment of chitosan and calcium chloride was the most effective, leading to 40% less weight loss, 45% (3.70 N) increase in firmness, less overall colour difference, and more than 0.5 log CFU/g inhibition on mesophilic and psychrotropic growths on day 13 of storage as compared to control group. In addition, these treatments also inhibited degradation of pectin chains. Nanostructural analysis of fruit pectin via atomic force microscopy (AFM) indicated that firmness was closely related to the nanostructure of sodium carbonate-soluble pectin (SSP). Short and narrow SSP chains were observed more in samples with less firmness. We conclude that edible coating of chitosan combined with calcium chloride treatment synergistically extends the shelf-life of fresh-cut honeydew melon by maintaining the integrity of SSP via interactions between SSP and calcium ions or protonated chitosan groups. [ABSTRACT FROM AUTHOR]

This experiment was conducted to investigate the possibility of mixing spent mushroom substrate (SMS) with manure composts for honeydew melon ( Cucumis melo L. inodorus) seedling production in organic agriculture. The treatments evaluated were 100 % SMS, mixtures of SMS, and chicken manure compost, mixtures of SMS and cattle manure compost in different ratios: 80, 60, 40, and 20 %. The experiment was arranged in a randomized complete block design with three replications under greenhouse conditions. Some physical and chemical characteristics of growing media were determined. Germination rate, morphological growth, survival rate, and nutrient uptake of seedlings were also measured. The results indicated that the addition of manure composts to SMS-based growing media produced a decrease in pH values, air capacity, an increase in electrical conductivity, total water holding capacity, and a difference in nutrient concentrations. Eighty percent SMS can be used in mixtures with manure composts for honeydew melon seedling production. However, SMS at the rate of 40 % gave the most suitable condition for honeydew melon seedling performance. [ABSTRACT FROM AUTHOR]

Several techniques have been developed to preserve the quality of horticultural products throughout the supply chain. Edible coatings represent a promising technology as they can improve quality and extend shelf life of fruit and vegetables by changing gases and moisture permeabilties, enhancing fruit appearance, and reducing microbial contamination. The aim of this work was to assess the effectiveness of two kinds of novel coatings on the shelf life extension of Honeydew winter melons during retail. Sixty melons were used: 24 were uncoated as control; 18 were treated with a cellulose polymer coating (F1) and 18 with a synthetic polymer (F2) coating. Upon arrival, and after 6, 9 and 13 days at 13°C, six melons/ treatment were individually analyzed for internal O2, ethylene and ethane concentrations, fermentative metabolites, quality parameters, and aroma pattern. Already after six days, internal O2 levels in coated fruit fell to ~1% in F1 and ~3% in F2 melons, triggering fermentative pathways as shown by the increased productions, mainly in F1 fruit, of acetaldehyde, ethanol, ethyl acetate, and ethane. This pattern caused changes in the responses of electronic nose sensors which were able to distinguish the three treatments. Coating did not influence fruit firmness and internal ethylene concentration. F1 coating reduced soluble solids content, strongly enhanced skin glossiness, and delayed yellowing, but it was not able to prevent moisture losses. In contrast, F2 coating significantly reduced weight loss and showed a slight positive effect on fruit appearance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The water state and freezable water were improved by CO 2 pressurization. • The combined strategy significantly reduced the ice crystal size. • The drip loss of thawed melon samples was better controlled. • Physicochemical indexes of CO 2 USIF samples were better maintained. The effects of CO 2 pressurization combined with ultrasound-assisted immersion freezing (CO 2 USIF) on improving the freezing quality of honeydew melon were studied. The cut melon samples were first subjected to 0.2, 0.5 and 0.8 MPa CO 2 pressure for 2 h respectively, and then frozen by an ultrasound-assisted freezing device. The results indicated that the CO 2 pressurization affected the water state and reduced the freezable water content. Cryo-observed results showed the ice crystal area of the 0.5CO 2 USIF sample was 66.6% smaller than that of the SF, and 60.8% smaller than that of the IF. The drip loss of 0.5CO 2 USIF sample was 58.2% lower than that of SF. The indexes of vitamin C, flavor, texture and color of CO 2 USIF samples were kept better. The SEM results showed that the cell structures of CO 2 USIF samples were better maintained. These demonstrated that CO 2 USIF technology has application potential in improving the quality of frozen food. [ABSTRACT FROM AUTHOR]

Phenolic composition of different extracts of honeydew melon seeds and their antioxidant activity was determined for the first time. Phenolic compounds were identified using a reversed phase high performance liquid chromatography with diode array detection (HPLC-DAD) method. Results showed the identification of five phenolic compounds in water extract namely gallic acid and its derivative, hydroxybenzoic acid and catechin derivatives and caffeic acid.There were nine phenolic compounds identified in methanol–water extract, which are caffeic acid, two vanillic acid derivatives, ellagitanins, quercetin-3-rutinoside, derivatives of syringic acid and ellagic acid. The amounts of gallic acid, caffeic acid and catechin were higher among all phenolic compounds. Total phenolic compounds and radical scavenging activity were higher in water and methanol–water extract than their corresponding methanol extracts. In conclusion, melon seeds are a good source of natural antioxidants with significant biological functions and may serve as food ingredients and as fortifying material for maintaining shelf life.

Interest in specialty melons (Cucumis melo) with distinctive fruit characteristics has grown in the United States in recent years. However, disease management remains a major challenge in specialty melon production. In this study, grafting experiments were conducted to determine the effectiveness of using Cucumis metulifer, a species known for its genetic resistance to root-knot nematodes (RKNs; Meloidogyne spp.), as a potential rootstock for managing RKNs in susceptible specialty melon cultivars. In the greenhouse experiment, honeydew melon 'Honey Yellow' was grafted onto C. metulifer and inoculated with M. incognita race 1. The grafted plants exhibited significantly lower gall and egg mass indices and fewer eggs compared with non- and self-grafted 'Honey Yellow'. Cucumis metulifer was further tested as a rootstock in conventional and organic field trials using honeydew melon 'Honey Yellow' and galia melon 'Arava' as scions. 'Honey Yellow' and 'Arava' grafted onto C. metulifer exhibited significantly lower galling and reduced RKN population densities in the organic field; however, total and marketable fruit yields were not significantly different from non- and self-grafted plants. Although the improvement of RKN resistance did not translate into yield enhancements, incorporating grafted specialty melons with C. metulifer rootstock into double-cropping systems with RKN-susceptible vegetables may benefit the overall crop production by reducing RKN population densities in the soil. At the conventional field site, which was not infested with RKNs, 'Honey Yellow' grafted onto C. metulifer rootstock had a significantly lower total fruit yield than non-grafted 'Honey Yellow' plants; however, fruit yields were similar for 'Arava' grafted onto C. metulifer rootstock and non-grafted 'Arava' plants. Although no significant impacts on the fruit quality attributes of 'Honey Yellow' were observed, grafting onto C. metulifer decreased the flesh firmness of 'Arava' in both field trials and resulted in a reduction in total soluble solids content under conventional production. In summary, grafting RKN-susceptible melons onto C. metulifer rootstock offers promise for growing these specialty melons; however, more studies are needed to elucidate the scion-rootstock interaction effect on fruit yield and quality. [ABSTRACT FROM AUTHOR]

Highlights: [•] The influence of selected rootstocks were tested for inodorus melon. [•] Physical properties, chemical data, volatiles, sensory descriptors were determined. [•] The data, statistically elaborated, allowed selecting the most appropriate rootstock. [•] RS841 and Polifemo can be successfully used as rootstocks for the inodorus melon. [•] They improved disease resistance and productivity maintaining the fruit quality. [ABSTRACT FROM AUTHOR]

Highlights: [•] Deficit irrigation increased root growth in cv. Mission (cantaloupe; reticulatus). [•] Deficit irrigation had no adverse impact on melon fruit quality. [•] Significant water savings were obtained with deficit irrigation in cvs. Mission and Da Vinci (tuscan; reticulatus). [•] Due to high yield reduction, deficit irrigation may not be applicable for cv. Super Nectar(honeydew;inodorus). [Copyright &y& Elsevier]

Theory indicates that landscape composition affects transmission of vector-borne crop diseases, but few empirical studies have investigated how landscape composition affects plant disease epidemiology. Since 2006, Bemisia tabad (Gennadius) has vectored the cucurbit yellow stunting disorder virus (CYSDV) to cantaloupe and honeydew melons (Cucumis me/o L.) in the southwestern United States and northern Mexico, causing significant reductions in yield of fall melons and increased use of insecticides. Here, we show that a landscape-based approach allowing simultaneous assessment of impacts of local (i.e., planting date) and regional (i.e., landscape composition) factors provides valuable insights on how to reduce crop disease risks. Specifically, we found that planting fall melon fields early in the growing season, eliminating plants germinating from seeds produced by spring melons after harvest, and planting fall melon fields away from cotton and spring melon fields may significantly reduce the incidence of CYSDV infection in fall melons. Because the largest scale of significance of the positive association between abundance of cotton and spring melon fields and CYSDV incidence was 1,750 and 3,000 m, respectively, reducing areas of cotton and spring melon fields within these distances from fall melon fields may decrease CYSDV incidence. Our results indicate that landscape-based studies will be fruitful to alleviate limitations imposed on crop production by vector-borne diseases. [ABSTRACT FROM AUTHOR]

This study evaluated the potential of modified atmospheres (MAs) combining high oxygen (O2) and high carbon dioxide (CO2) levels to extend the shelf-life of fresh-cut honeydew melon. Firstly, the effect of MA on the growth and volatile organic metabolite production of Candida sake, Leuconostoc mesenteroides and Leuconostoc gelidum, which had all been previously isolated from spoiled commercial fresh-cut honeydew melon, was evaluated separately on honeydew melon agar at 7°C. Additionally, the effect of selected MAs on the microbial, physico-chemical and sensory quality of commercial fresh-cut honeydew melon cubes was evaluated at 7°C. The results showed that MAs with high O2 and high CO2 levels greatly retarded the growth, CO2 and volatile metabolite production (i.e. ethanol, 2-methyl-1-butanol, ethyl acetate, phenylacetic acid, nonanal) of C. sake on honeydew melon agar; especially MAs consisting of 50% O2 +50% CO2 and 70% O2 +30% CO2. In contrast, the MAs evaluated only had a minor effect on the growth and volatile metabolite production of L. mesenteroides and L. gelidum. Overall, the effect of MAs on colour, juice leakage, juiciness, and firmness of fresh-cut honeydew melon was small during storage. Sensory preference was generally for fresh-cut honeydew melon cubes packaged in MA of 50% O2 +50% CO2. These were still acceptable on day five of storage and had appreciably lower populations of yeasts and lactic acid bacteria, lower quantities of volatile organic compounds, but slightly stronger colour oxidation compared to honeydew melon that was packaged in air. Additionally, most of the samples packed in air had blown by day five due to the large quantity of CO2 production during storage. Therefore, 50% O2 +50% CO2 is a potential MA solution for extending the shelf-life of fresh-cut honeydew melon. [ABSTRACT FROM AUTHOR]

The Cucumis melo L. inodorus honeydew melon variant is one of the most consumed melons in the USA, and has important commercial and nutritional value. There is a need for improvement of several genetic traits in the US honeydew melon, such as nutrition, drought tolerance, and disease resistance. We investigated the existing regeneration media and optimized the medium composition for an elite honeydew diploid breeding line, '150', using cotyledonary explants. Four combinations of three different plant growth regulators, 6-benzyladenine, abscisic acid, and indole-3-acetic acid (IAA), were tested in the shoot regeneration media. The presence of IAA in the medium caused the cotyledon explants to curl away from the medium, which made antibiotic selection problematic in our previous study. Omission of IAA from the culture media eliminated this problem and did not impact the shoot regeneration capacity of the cotyledonary explants. We also estimated the ploidy of regenerated plants using flow cytometry, and 50-60% were found to be polyploid (tetraploid or mixoploid). However, contrary to other studies, these polyploid plants did not show major morphological differences compared to the diploid plants. [ABSTRACT FROM AUTHOR]

The survival and growth of Salmonella salford, Escherichia coli and Listeria innocua on the surface of fruit with inedible skins was investigated. Passionfruit, banana, cantaloupe (rock melon) and honeydew melon were inoculated by immersion in solutions containing two inoculum levels and then stored under normal storage and distribution temperature regimes. A low (ca. 103 cfu ml−1) and high (105–106 cfu ml−1) inoculum concentration was used for each organism. Bananas were stored for 13 days at 18 °C, passionfruit for 6 days at 10 °C, cantaloupes for 7 days at 8 °C and honeydew melons for 1 day at 12 °C then 5 days at 8 °C. Generally, the fruit did not support growth under the conditions employed, although test organisms could usually be recovered either directly or after an enrichment step. The exception was the growth of L. innocua on the skin of cantaloupe. Significant growth was observed for both the low and high inoculum levels during storage at 8 °C. Cantaloupes inoculated with 2.4×106 cfu ml−1 had an initial level of 3.4×103 cfu cm−2 and this increased to 2.9×105 cfu cm−2 during 7 days storage. For the low inoculum (1.3×103 cfu ml−1), levels that could only be detected by enrichment initially increased to 1.4×102 cfu cm−2. [Copyright &y& Elsevier]

The objectives of this study were to assess the degree of restriction fragment length polymorphism (RFLP) in Cucumis melo and to determine interrelationships among cultivated varieties. Initial screening of a genomic PstI library revealed that approximately 40% of the clones were repetitive. A total of 162 unique and low-copy sequence clones were hybridized to seven diverse accesions of C. melo and a C. sativus cultivar 'Pacer' to evaluate RFLP variation. Of these, 130 probes (80%) detected a polymorphism between C. melo accessions and C. sativus, and the majority were polymorphic with more than one enzyme digest. In contrast, only 53 probes (33%) were useful in differentiating at least one of the seven accessions. Of those, only 9% were informative with more than one enzyme digest. This indicates that within C. melo, the differences among accessions are due to infrequent base substitutions, whereas between the two species, differences are mainly due to genome rearrangements such as insertions and deletions or numerous base substitutions. Of the informative probes, 34 were used in analyzing 44 C. melo lines to establish a data base of RFLP hybridization patterns. Percent similarity based on RFLP profiles was computed among lines and analyzed by principal component analysis, to visualize relationships among lines. There were clear demarcations among, but not within, muskmelon and honeydew groups. [ABSTRACT FROM AUTHOR]