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Grafting high yielding tomato cultivars (Solanum lycopersicum L.) onto vigorous rootstocks can increase marketable yields, but questions remain regarding optimal cultural and growing conditions such as pinching and plant spacing. This study addressed some of the dynamics between grafted plants and cultural practices. Two scions, ‘Tasti-Lee’ (TL) and ‘Mountain Fresh Plus’ (MFP) were grafted onto each of three rootstocks, ‘Beaufort’, ‘Arnold’, and ‘Shield’. Plants were pinched (removal of main shoot to induce both axillary shoots to grow) or non-pinched, and spaced at 56 or 61 cm. All 32 grafted treatments were compared to the grower standard: non-grafted TL and MFP spaced at 46 cm, which were non-pinched. Fruit quality traits including soluble solids content, pH, lycopene concentration, and titratable acidity were recorded for fruit harvested from tomatoes grafted onto ‘Arnold’, ‘Beaufort’, ‘Shield’ and non-grafted TL. The overall effect of grafting TL and MFP onto vigorous rootstocks ‘Arnold’, ‘Beaufort’, and ‘Fortamino’ increased marketable yields per hectare by 24-35% compared to non-grafted grower standards. The rootstock ‘Shield’ did not significantly increase yields with either scion. TL had a more positive response to grafting than MFP. ‘Arnold’, ‘Beaufort’, and ‘Fortamino’ significantly increased TL fruit size, but the fruit size results were not as significantly impacted by graft treatments for MFP. Plants spaced at 56 compared to 61 cm generated similar yields. Pinched plants significantly increased yields over non-pinched plants by 15% in 2018 but did not impact yield in 2017. No consistent difference was observed between pinched and non-pinched plants with regard to fruit size, only plants grafted with ‘Shield’ benefited significantly from being pinched. Soluble solids content, pH, total lycopene concentration, and titratable acidity differed slightly between grafted and non-grafted plants but was unlikely to positively or negatively affect overall perception of fruit quality in tomatoes. A partial budget analysis revealed that grafting with ‘Arnold’ or ‘Beaufort’ consistently increased profits in this low-disease field.

In triploid (seedless) watermelon [Citrullus lanatus var. lanatus (Thunb. Matsum. and Nakai)], hollow heart (HH) is a disorder that is expressed as a crack in the center of the fruit that expands to an open cavity. Although HH incidence and severity is part of a screening process for marketable watermelon fruit during cultigen evaluations, HH incidence is highly variable with growing season, even when the best cultural practices are used. Placental tissue firmness is also measured because firmness is related to the marketability of watermelon and may be related to HH. Genetic and environmental factors can influence watermelon HH development, including plant genetics, pollen amount and viability, pollinator activity, and temperature and rainfall fluctuations. We used seedless watermelon cultigen evaluation data collected over 3 years (2012–14) to determine the relationship between germplasm HH and tissue firmness. Transplanted watermelon representing 30 to 44 cultigens per year were grown at the Central Crops Research Station, Clayton, NC, and interplanted with pollenizers ‘Ace’ and/or ‘SP-6’. Harvested fruit were cut length-wise and rated for HH incidence and severity. Flesh firmness was determined by a handheld penetrometer at five locations in the flesh (stem end, top side, ground spot, blossom end, and heart). A common cultigen subset, consisting of 13 cultigens that were grown in all three experiments, was used for analysis of HH severity and incidence, and placental firmness. The presence of HH was negatively correlated with tissue firmness in both the large multiyear cultigen set (R2 = −0.32; P = 0.0001) and the common cultigen set (R2 = −0.78; P = 0.0001). Cultigens with lower watermelon tissue firmness values had higher HH incidence and severity. By using multiyear cultigen studies and logistic regression, we were able to detect trends for cultigen susceptibility to this highly variable disorder. Using logistic regression, the probability of HH development was highest for ‘Bold Ruler’, ‘Liberty’, and ‘Affirmed’, and lowest for ‘Maxima’ and ‘Captivation’. The identification of cultigens with a tendency for higher or lower rates of HH will be useful for further research of the causes of HH. Measurements of placental flesh firmness may be useful indicators of susceptible cultigens.

U.S. black raspberry (BR) production is currently limited by narrowly adapted, elite germplasm. Improved understanding of genetic control and genotype-by-environment interactions (GEI) of pomological traits will inform the development of improved BR germplasm and cultivars. To this end, analysis of a multi-environment trial of two BR mapping populations derived from crosses of commercial cultivars with wild accessions is providing insights into genetic variation, quantitative trait loci (QTL), and GEI related to traits of horticultural value. Twenty-six horticultural and fruit quality traits were evaluated in two mapping populations over three years at four distinct locations representative of current U.S. BR production. One fruit quality trait, drupelet count, has been analyzed, and nine additional fruit quality traits are being analyzed. Random factor analysis of genetic effect was used to account for missing data. GEI analysis was performed using a Bayesian approach to Finlay-Wilkinson regression and genotyping-by-sequencing (GBS)-derived genomic relationship matrices, with the purpose of verifying relatedness and identifying genotypes with stable performance over environments. Genetic maps were reconstructed using GBS-derived markers and the latest genome assembly for BR. Among relevant results, pedigree verification led to construction of reliable linkage maps, and a QTL spanning a one to five megabase region containing several hundred genes was identified on chromosome 1. This region has a stable influence over drupelet count over environments (location by year). These and related findings are expected to guide further genetic characterization of BR fruit quality, management of breeding germplasm, and development of improved BR cultivars for U.S. production.

Postmenopausal status is associated with an increase in total and abdominal body fat as well as increased incidence of insulin resistance and cardiovascular disease. The purpose of this study was to determine if watermelon supplementation affects select systemic markers of atherosclerosis and measures of insulin resistance in overweight and obese postmenopausal women. We hypothesized that overweight and obese postmenopausal women consuming 100% watermelon puree daily for 6 weeks would have improved levels of select systemic markers connected with cardiovascular disease without changing markers of insulin resistance. To test this hypothesis, overweight and obese postmenopausal women were recruited to participate in this study. Participants were randomly assigned to either the control group (no intervention) or the watermelon puree group (WM) for 6 weeks. Plasma concentration of markers connected with atherosclerosis and glycemic control were measured pre- and poststudy. A significant 6% decrease in soluble vascular cell adhesion molecule-1 occurred pre- to poststudy in WM, P = .003. The pattern of change in fasting blood glucose (P = .633), insulin (P = .158), and homeostatic model assessment–estimated insulin resistance (P = .174) did not differ between groups. Pre- to poststudy increases were measured in the fasting plasma concentration of l -arginine (8%, P = .005), cis-lycopene (32%, P = .003), and trans-lycopene (42%, P = .003) in WM. We conclude that 6 weeks of watermelon supplementation improved soluble vascular cell adhesion molecule-1 levels, a marker connected to atherogenesis, independent of changes in body composition or glycemic control.

This study investigated the effects of two doses of freeze-dried watermelon (WM) on bone and lipid parameters in ovariectomized (OVX) mice, a model of post-menopausal osteoporosis. Three-month-old C57BL/6 female mice (n=46) were sham-operated (SHAM) or OVX and randomly assigned to the control or WM diets for 12 weeks: SHAM-control, OVX-control, OVX+1%, or 10% (wt/wt) freeze-dried WM. All diets were isocaloric and isonitrogenous, and had the same calcium and phosphorus concentrations. Freeze-dried WM supplementation was not able to prevent the decrease in whole body, tibial, and lumbar bone mineral density due to estrogen deficiency. Micro-computed tomography analyses showed that WM was also not able to modulate changes in tibial trabecular and cortical bone microarchitecture due to ovariectomy. However, the lumbar trabecular micro-architecture analyses revealed that the WM-10% group had a similar connectivity density, trabecular number, trabecular separation, and structure model index as the SHAM group. Supplementation with 10% WM reduced plasma cholesterol and total liver lipids to the level of the SHAM group but was still similar to that of the OVX-control group. Supplementation with 10% WM increased liver catalase (CAT) mRNA levels but had no effects on mRNA levels of glutathione peroxidase (GPX) and the pro-inflammatory cytokine interleukin-6. There were no differences in plasma activity of the antioxidant enzymes GPX and CAT between all treatment groups. Our findings demonstrate some positive effects of watermelon for modulating lipids and attenuating lumbar vertebral bone loss arising from ovarian hormone deficiency.

Grafting is used in watermelon [Citrullus lanatus (Thunb.) Matsum and Nakai] production as a means to combat soilborne diseases. To support the development of new rootstock cultivars in the United States, we screened cucurbit germplasm accessions for resistance to verticillium wilt (caused by Verticillium dahliae Kleb.) and for compatibility as watermelon rootstocks. Screening was done using a field naturally infested with V. dahliae [5 and 7.5 colony-forming units (cfu)·g−1 soil in 2017 and 2018, respectively], and plants were inoculated at transplanting (1.5 and 104 cfu of V. dahliae per plant in 2017 and 2018, respectively). In 2017, 56 germplasm accessions from three genera commonly used as rootstocks, Cucurbita, Lagenaria, and Benincasa, were sourced from the U.S. Department of Agriculture (USDA) National Plant Germplasm System and area under the verticillium wilt (disease) progress curve (AUDPC) values ranged from 16 to 397. The 14 accessions with the lowest AUDPC values and good germination (>40%) were used as rootstocks along with the commercial rootstock cv. Tetsukabuto (control), and all were grafted with watermelon cv. Secretariat as the scion in 2018. Grafted plant survival rate was greatest for ‘Tetsukabuto’ (90%) and the accession PI 381840 (L. siceraria) (89%), and ranged from 22% to 85% for all other accessions. All grafted treatments that produced mature fruit in 2018 tended to flower at the same time as nongrafted ‘Secretariat’, with first male and female flowers occurring in 45 to 50 days and 44 to 51 days after transplanting, respectively. There were no significant differences in AUDPC values due to grafting or when accessions were compared with ‘Tetsukabuto’. Only six accessions produced mature fruit when grafted with ‘Secretariat’, indicating they were compatible for watermelon grafting. Fruit weight and number as well as total soluble solids, pH, lycopene content, rind firmness and thickness, and dry matter content were similar for all accessions and ‘Tetsukabuto’ grafted on ‘Secretariat’. Only fruit flesh firmness differed and was highest for ‘Secretariat’ grafted on ‘PI 491316’ and lowest for ‘Secretariat’ grafted on ‘PI 49174’. The six verticillium wilt-tolerant accessions that were compatible with watermelon could potentially be used as rootstocks or as sources of genetic resistance in rootstock breeding programs.

U.S. black raspberry (BR) production is currently limited by narrowly adapted, elite germplasm. An improved understanding of genetic control and the stability of pomological traits will inform the development of improved BR germplasm and cultivars. To this end, the analysis of a multiple-environment trial of a BR mapping population derived from a cross that combines wild ancestors introgressed with commercial cultivars on both sides of its pedigree has provided insights into genetic variation, genotype-by-environment interactions, quantitative trait loci (QTL), and QTL-by-environment interactions (QEI) of fruit quality traits among diverse field environments. The genetic components and stability of four fruit size traits and six fruit biochemistry traits were characterized in this mapping population following their evaluation over three years at four distinct locations representative of current U.S. BR production. This revealed relatively stable genetic control of the four fruit size traits across the tested production environments and less stable genetic control of the fruit biochemistry traits. Of the fifteen total QTL, eleven exhibited significant QEI. Closely overlapping QTL revealed the linkage of several fruit size traits: fruit mass, drupelet count, and seed fraction. These and related findings are expected to guide further genetic characterization of BR fruit quality, management of breeding germplasm, and development of improved BR cultivars for U.S. production.

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Lycopene content in tomato fruit is largely under genetic control and varies greatly among genotypes. Continued improvement of lycopene content in elite varieties with conventional breeding has become challenging, in part because little is known about the underlying molecular mechanisms in high-lycopene tomatoes (HLYs). We collected 42 HLYs with different genetic backgrounds worldwide. High-performance liquid chromatography (HPLC) analysis revealed lycopene contents differed among the positive control wild tomato Solanum pimpinellifolium, HLYs, the normal lycopene cultivar “Moneymaker”, and the non-lycopene cultivar NC 1Y at the pink and red ripe stages. Real-time RT-PCR analysis of expression of the 25 carotenoid biosynthesis pathway genes of each genotype showed a significantly higher expression in nine upstream genes (GGPPS1, GGPPS2, GGPPS3, TPT1, SSU II, PSY2, ZDS, CrtISO and CrtISO-L1 but not the well-studied PSY1, PDS and Z-ISO) at the breaker and/or red ripe stages in HLYs compared to Moneymaker, indicating a higher metabolic flux flow into carotenoid biosynthesis pathway in HLYs. Further conversion of lycopene to carotenes may be prevented via the two downstream genes (β-LCY2 and ε-LCY), which had low-abundance transcripts at either or both stages. Additionally, the significantly higher expression of four downstream genes (BCH1, ZEP, VDE, and CYP97C11) at either or both ripeness stages leads to significantly lower fruit lycopene content in HLYs than in the wild tomato. This is the first systematic investigation of the role of the complete pathway genes in regulating fruit lycopene biosynthesis across many HLYs, and enables tomato breeding and gene editing for increased fruit lycopene content.

Sweet dessert watermelon (Citrullus lanatus) is one of the most important vegetable crops consumed throughout the world. The chemical composition of watermelon provides both high nutritional value and various health benefits. The present manuscript introduces a catalog of 1,679 small molecules occurring in the watermelon and their cheminformatics analysis for diverse features. In this catalog, the phytochemicals are associated with the literature describing their presence in the watermelon plant, and when possible, concentration values in various plant parts (flesh, seeds, leaves, roots, rind). Also cataloged are the chemical classes, molecular weight and formula, chemical structure, and certain physical and chemical properties for each phytochemical. In our view, knowing precisely what is in what we eat, as this catalog does for watermelon, supports both the rationale for certain controlled feeding studies in the field of precision nutrition, and plant breeding efforts for the development of new varieties with enhanced concentrations of specific phytochemicals. Additionally, improved and comprehensive collections of natural products accessible to the public will be especially useful to researchers in nutrition, cheminformatics, bioinformatics, and drug development, among other disciplines.

Phosphorus (P) deficiency commonly results in the development of red-to-purple coloration in plant foliage, typically attributed to anthocyanins. Betacyanins are a red pigment found in some plant species that do not produce anthocyanins, including Alternanthera sp. This study was conducted to investigate the effects of P nutrition on the betacyanin concentration and subsequent foliar coloration of ‘Purple Prince’, ‘Brazilian Red Hots’, and ‘Little Ruby’ alternanthera (Alternanthera brasiliana). The purpose of this study was to determine whether P fertilization management could enhance the coloration and aesthetic appeal of alternanthera. Custom fertilizers provided P concentrations of 0, 2.5, 5, 10, and 20 mg·L−1 P. One-half of the plants from each P concentration were restricted to 0 mg·L−1 P 1 month after transplant to determine whether adequate size could be attained before withholding P. Differences in P response were observed among cultivars for hue, betacyanin content, and plant size. Concentrations ≤5 mg·L−1 P resulted in plants that were more compact in terms of plant height and diameter, had deeper red foliage coloration, and greater foliar betacyanins compared with plants grown with greater P concentrations. Plants initially grown with 5 or 10 mg·L−1 P attained marketable size before P restriction and developed more red pigmentation compared with plants grown with P for the remaining duration of the study. Regression analysis demonstrated height was maximized with 3 to 8 mg·L−1 P, diameter with 4.1 to 8.4 mg·L−1 P, and branching with 10.0 mg·L−1 P. Foliar betacyanin concentrations were greatest in plants grown without P, reaching 269 mg/100 g fresh weight, whereas plants grown with 10 or 20 mg·L−1 P were 95% less (averaged ≈13 mg/100 g fresh weight). This study demonstrates that P restriction can benefit the aesthetic appeal of alternanthera and provides the first confirmation that P nutrition is associated with betacyanin accumulation.

Grafting watermelon scions to interspecific squash hybrids has been found to increase fruit firmness. Triploid (seedless) watermelon are prone to hollow heart (HH), an internal fruit disorder characterized by a crack in the placental tissue expanding to a cavity. Although watermelon with lower tissue firmness tend to have a higher HH incidence, associated differences in cell wall polysaccharide composition are unknown. Grafting “Liberty” watermelon to “Carnivor” (interspecific hybrid rootstock, C. moschata × C. maxima) reduced HH 39% and increased tissue firmness by 3 N. Fruit with and without severe HH from both grafted and non-grafted plants were analyzed to determine differences in cell wall polysaccharides associated with grafting and HH. Alcohol insoluble residues (AIR) were sequentially extracted from placental tissue to yield water soluble (WSF), carbonate soluble (CSF), alkali soluble (ASF), or unextractable (UNX) pectic fractions. The CSF was lower in fruit with HH (24.5%) compared to those without HH (27.1%). AIRs were also reduced, hydrolyzed, and acetylated for GC-MS analysis of monosaccharide composition, and a portion of each AIR was methylated prior to hydrolysis and acetylation to produce partially methylated alditol acetates for polysaccharide linkage assembly. No differences in degree of methylation or galacturonic and glucuronic acid concentrations were found. Glucose and galactose were in highest abundance at 75.9 and 82.4 μg⋅mg–1 AIR, respectively, followed by xylose and arabinose (29.3 and 22.0 μg⋅mg–1). Mannose was higher in fruit with HH (p < 0.05) and xylose was highest in fruit from grafted plants (p < 0.05). Mannose is primarily found in heteromannan and rhamnogalacturonan I side chains, while xylose is found in xylogalacturonan or heteroxylan. In watermelon, 34 carbohydrate linkages were identified with galactose, glucose, and arabinose linkages in highest abundance. This represents the most comprehensive polysaccharide linkage analysis to date for watermelon, including the identification of several new linkages. However, total pectin and cell wall composition data could not explain the increased tissue firmness observed in fruit from grafted plants. Nonetheless, grafting onto the interspecific hybrid rootstock decreased the incidence of HH and can be a useful method for growers using HH susceptible cultivars.

‘Liz’ and ‘Rocco’ are new short-day (June-bearing) strawberry (Fragaria ×ananassa Duch. ex Rozier) cultivars from the North Carolina State University strawberry breeding program in Raleigh, NC. The most outstanding characteristic of ‘Liz’ is its consistently high yields. Total and marketable yields of ‘Liz’ were higher than those of other cultivars tested most years in our trials in North Carolina. Firmness of ‘Liz’ is comparable to ‘Camarosa’. Because of its consistent high yields and moderate firmness, ‘Liz’ can be considered an alternative to ‘Camarosa’. The most outstanding characteristics of ‘Rocco’ are its early season ripening and high soluble solids content. Total yield of ‘Rocco’ is higher than that of ‘Sweet Charlie’ and comparable to cultivars that ripen later in the season. ‘Rocco’ should be considered an alternative to ‘Sweet Charlie’ for early production. U.S. Plant Patents have been submitted for ‘Liz’ and ‘Rocco’. North Carolina Strawberry Association; North American Strawberry Growers Association; Southern Region Small Fruit Consortium; Golden Leaf Foundation; Virginia Strawberry Growers Association This research was partially funded by the North Carolina Strawberry Association, North American Strawberry Growers Association, Southern Region Small Fruit Consortium, and the Golden Leaf Foundation. On-farm trials in Virginia were funded in part by the Virginia Strawberry Growers Association. We gratefully acknowledge the North Carolina Department of Agriculture and Consumer Services for their assistance with conducting trials at research stations in the state of North Carolina. Extension personnel from North Carolina State University, the University of Georgia, and Clemson University facilitated on-farm trials in NC, GA, and SC, respectively. We also thank Norton Creek Farm in Cashiers, NC, and Nathan Moss for their help with propagation of this cultivar during the last years of trialing. The North Carolina Micropropagation and Research Unit produced virus-tested plant material that was distributed to test sites and nurseries and tested 'Liz' and 'Rocco' for 22 known strawberry viruses.

Fruit texture and firmness are important cues of blueberry quality for the fresh market. These attributes contribute to consumer acceptance, resistance to bruising during harvesting and transportation, and shelf-life. Thus, fruit firmness and texture are major priorities for blueberry breeders, producers and distributors. In this study, the discriminative power of texture analysis was examined using penetration tests with different probes and double compression for texture profile analysis (TPA). Mechanical parameters taken from the force deformation curves used to dissect texture subcomponents in blueberries that are associated with specific tissue layers. Principal component analysis (PCA) allows to filter and identify mechanical parameters that significantly discern the most variation amongst 24 blueberry genotypes and showed that texture in this crop is multi-trait and cultivar-dependent. Texture analysis was used also on blueberries stored over six weeks to identify mechanical parameters that could be used as predictors for long shelf life. Additionally, the mechanical parameters were correlated with dynamometer data to determine the utility and accuracy of a simple handheld device to measure fruit firmness in blueberries. This study provides a framework for the identification and characterization of the subcomponents of texture in highbush blueberry.

The development of more cold-tolerant short-cycle banana cultivars has made subtropical production possible, but fruiting may be unreliable in colder margins, such as the coastal region of Alabama, as a result of cold winter temperatures and other suboptimal growing conditions. Thus, the objectives of this study were to determine plant growth parameters that predict flowering, and to evaluate vegetative and reproductive growth of Cavendish and non-Cavendish banana cultivars. Pseudostem circumference and the height-to-circumference ratio (HCR) for tall cultivars and HCR for medium cultivars exhibited linear or quadratic relationships when regressed to the number of days from planting to inflorescence emergence (DPE), and hence were the best predictors of inflorescence emergence. The banana cultivars Double, Grand Nain, Cardaba, Ice Cream, and Goldfinger demonstrated cropping potential by producing mature bunches in the cooler environment of the subtropics and currently offer the best possibilities for banana production in Alabama.

Tomato (Solanum lycopersicum L.) is a warm-season, cold-sensitive crop that shows slower growth and development at temperatures below 18 °C. Improving suboptimal temperature tolerance would allow earlier planting of field-grown tomato and a reduction in energy inputs for heating greenhouses. Grafting tomato onto high-altitude Solanum habrochaites (S. Knapp and D.M. Spooner) accessions has proven effective at improving scion suboptimal temperature tolerance in limited experiments. This study was conducted to determine whether commercially available tomato rootstocks with differing parental backgrounds and root system morphologies can improve the tolerance of scion plants to suboptimal temperature. Two controlled environment growth chambers were used and maintained at either optimal (25 °C day/20 °C night) or suboptimal (15 °C day/15 °C night) temperatures. The cold-sensitive tomato cultivar Moneymaker was used as the nongrafted and self-grafted control as well as scion grafted on ‘Multifort’ (S. lycopersicum × S. habrochaites), ‘Shield’ (S. lycopersicum), and S. habrochaites LA1777 rootstocks. Plants were grown for 10 days in 3.8 L plastic containers filled with a mixture of calcined clay and sand. ‘Multifort’ rootstock significantly reduced the amount of cold-induced stress as observed by larger leaf area and higher levels of CO2 assimilation and photosystem II quantum efficiency. ‘Multifort’ had significantly longer roots, having 42% to 56% more fine root (diameter less than 0.5 mm) length compared with the other nongrafted and grafted treatments. Leaf starch concentration was significantly lower in ‘Multifort’-grafted plants at suboptimal temperatures compared with the self-grafted and nongrafted controls and the ‘Shield’-grafted plants at the same temperature. The ability for ‘Multifort’ to maintain root growth at suboptimal temperatures may improve root system sink strength, thereby promoting movement of photosynthate from leaf to root even under cold conditions. This work demonstrates that a commercially available rootstock can be used to improve suboptimal temperature tolerance in cold-sensitive ‘Moneymaker’ scions.

Vitamin A deficiency (VAD) is one of the most prevalent micronutrient deficiencies that disproportionately affects low income populations in developing countries. Traditional breeding and modern biotechnology have significant potential to enhance micronutrient bioavailability in crops through biofortification. Bananas (Musa spp.) are economically important fruit crops grown throughout tropical and sub-tropical regions of the world where VAD is most prevalent. Some banana genotypes are rich in provitamin A carotenoids (pVACs), providing an opportunity to use bananas as a readily available vehicle for provitamin A delivery. This review summarizes the progress made in carotenoid research in bananas relative to banana diversity and the use of conventional breeding and transgenic approaches aimed at banana biofortification to address vitamin A deficiency. Existing reports on sampling strategies, pVAC retention and bioavailability are also evaluated as essential components for a successful banana biofortification effort. The wide variability of pVACs reported in banana cultivars coupled with recent advances in unraveling the diversity and genetic improvement of this globally important but often-neglected staple fruit crop underscores their importance in biofortification schemes. ispartof: Critical Reviews In Food Science And Nutrition vol:59 issue:21 pages:3498-3510 ispartof: location:United States status: published

Grafting watermelon (Citrullus lanatus) is a common practice in many parts of the world and has recently received increased interest in the United States. The present study was designed to evaluate early season growth, yield, and fruit quality of watermelon in response to grafting and in the absence of known disease pressure in a fumigated system. Field experiments were conducted using standard and mini watermelons (cv. Exclamation and Extazy, respectively) grafted onto 20 commercially available cucurbit rootstocks representing four species: giant pumpkin (Cucurbita maxima), summer squash (Cucurbita pepo), bottle gourd (Lagenaria siceraria), and interspecific hybrid squash [ISH (C. maxima × Cucurbita moschata)]. Nongrafted ‘Exclamation’ and ‘Extazy’ were included as controls. To determine early season growth, leaf area was measured at 1, 2, and 3 weeks after transplant (WAT). At 1 WAT, nongrafted ‘Exclamation’ produced the smallest leaf area; however, at 3 WAT, nongrafted ‘Exclamation’ produced the largest leaf area in 2015, and no differences were observed in 2016. Leaf area was very similar among rootstocks in the ‘Extazy’ study, with minimal differences observed. Marketable yield included fruit weighing ≥9 and ≥3 lb for ‘Exclamation’ and ‘Extazy’, respectively. In the ‘Exclamation’ study, highest marketable yields were observed in nongrafted ‘Exclamation’, and ‘Exclamation’ grafted to ‘Pelops’, ‘TZ148’, and ‘Coloso’, and lowest marketable yields were observed when using ‘Marvel’ and ‘Kazako’ rootstocks, which produced 47% and 32% of nongrafted ‘Exclamation’ yield, respectively. In the ‘Extazy’ study, the highest marketable yield was observed in nongrafted ‘Extazy’, and ‘Kazako’ produced the lowest yields (48% of nongrafted ‘Extazy’). Fruit quality was determined by measuring fruit acidity (pH), soluble solids concentration (SSC), lycopene content, and flesh firmness from a sample of two fruit from each plot from the initial two harvests of each year. Across both studies, rootstock had no effect on SSC or lycopene content. As reported in previous studies, flesh firmness was increased as a result of grafting, and nongrafted ‘Exclamation’ and ‘Extazy’ had the lowest flesh firmness among standard and mini watermelons, respectively. The present study evaluated two scions with a selection of 20 cucurbit rootstocks and observed no benefits in early season growth, yield, or phytonutrient content. Only three of 20 rootstocks in each study produced marketable yields similar to the nongrafted treatments, and no grafted treatment produced higher yields than nongrafted ‘Exclamation’ or ‘Extazy’. Because grafted seedlings have an associated increase in cost and do not produce increased yields, grafting in these optimized farming systems and using fumigated soils does not offer an advantage in the absence of soilborne pathogens or other stressors that interfere with watermelon production.

Blueberry (Vaccinium corymbosum L.) fruit, rich in anthocyanins, polyphenolics and antioxidant activity, has not been exploited fully for processing into juice. The objective of this study was to investigate the effect of commercial juice extraction enzymes (Cellubrix, Pectinex Ultra SPL, and Crystalzyme) on juice yield, total soluble solids (TSS), juice clarity, HPLC sugars profile, total anthocyanins (ACY), total phenolics (TPH), and antioxidant activity (assayed as FRAP). Enzyme treatments resulted in significantly (p ≤ 0.05) higher juice yield (86.91–87.29 mL/100 g with Pectinex and Crystalzyme as compared to 79.45 mL/100 g from control), higher juice clarity, and titratable acidity, and lower extraction loss. However, enzymes treatment had no effect on total soluble solids (°Brix), fructose, glucose, and total sugars. Generally, juice Hunter color values (L, a, and b), Hue angle (h°) and Chroma (C*) were affected positively by the enzymes treatment. As compared to the control (9.69 mg/100 mL), total ACY were significantly higher (11.49–12.90 mg/100 mL) in juice from enzyme-treated macerates; whereas there was no effect on TPH, determined as gallic acid equivalent (96-89‒101.30 mg GAE/100 mL) and FRAP antioxidant activity (3.87–3.97 μmol TE/100 mL). Total ACY, TPH, and FRAP were several-fold higher in the pomace than the juice.

A field study was conducted in 2014 and 2015 in an established 5-yr old commercial blackberry planting to determine the effect of vegetation-free strip width (VFSW) on ‘Navaho’ blackberry vegetative growth, yield and fruit quality parameters, identify the optimum VFSW for blackberry plantings in the southeastern USA, and provide practical groundcover management recommendations that can increase the productivity of blackberry plantings. In Fall 2013, tall fescue was seeded in-row and allowed to establish. In Spring 2014, VFSW treatments (0, 0.6, 0.9, 1.2, and 1.8 m) were established in a randomized complete block statistical design with four replications. Blackberry growth measurements included primocane and floricane number, cane diam, individual fruit weight and yield. Fruit quality measurements included, soluble solids concentration (SSC), titratable acidity (TA) and pH. Primocane number increased with increasing VFSW in both years. Floricane number increased with increasing VFSW in 2014. Primocane diam decreased with increasing VFSW in 2014 but had a quadratic response in 2015. Berry weight and cumulative yield increased with increasing VFSW in both years. The only berry quality component affected by VFSW was pH, which decreased as VFSW increased. Results indicate that widening the VFSW in blackberry from the current recommendation of 1.2 m to 1.8 m could provide growers a means to increase plant growth, berry weight, and cumulative yield blackberry of a planting.

The consumption of fresh muskmelons (Cucumis melo reticulatus L.) has been linked to severe illness outbreaks due to contamination with bacterial pathogens. Antimicrobial essential oils (EOs) were incorporated into wash water sprays and evaluated as potential agents for postharvest disinfection of ‘Athena’ muskmelons. Freshly harvested fruits were sprayed with 0.5% EOs from cinnamon leaf, thyme, or clove bud emulsified in a whey protein emulsion (WP) as potential washing disinfectants, together with deionized water, water with 200 µL·L−1 free chlorine (pH 7, free turbidity), or oil-free WP as controls. Melons were treated, stored at 4 °C and then evaluated weekly for weight loss, rind color, mesocarp firmness and the compositional quality traits soluble solids content (SSC), pH, β-carotene content, and total ascorbic acid (AsA) for up to 21 days. Essential oil–treated melons were not different from controls in fruit quality and composition with the exception of fruits treated with thyme oil, which were statistically lower in SSC (0.8 °Brix) than those treated with water or cinnamon oil treatment. Internal carbon dioxide was statistically higher (≈0.1% higher in value, equal to a 25% increase) in muskmelons receiving whey protein–based treatments after storage for at least 7 days. Overall, our results suggest that EOs as disinfectants have little effect on quality or composition of muskmelon fruit.

Objective: Postprandial fluxes in oxidative stress, inflammation, glucose, and lipids, particularly after a high-fat meal (HFM), have been implicated in the development of cardiovascular disease (CVD). The aim of this study is to determine whether acute freeze-dried mango consumption modulates the postprandial response to an HFM. We hypothesized that the addition of mango, which is a rich source of many bioactive components, to an HFM would lower postprandial triglycerides, glucose, and inflammation, and increase antioxidant enzymes, compared to a standard HFM alone. Methods: In a randomized cross-over study, 24 healthy adult males (18-25 years old) consumed a typical American breakfast (670 kcal; 58% fat) with or without the freeze-dried mango pulp (50 g). Lipids, glucose, antioxidant enzymes, and inflammatory markers were assessed at baseline/fasting and 1, 2, and 4 hours after the HFM. Results: Addition of mango resulted in lower glucose (95.8 ± 4.4 mg/dL; P = .002) and higher high-density lipoprotein cholesterol (HDL-C; 58.4 ± 2.7 mg/dL; P = .01) 1 hour post-HFM compared to control (glucose: 104.8 ± 5.4 mg/dL; HDL-C: 55.2 ± 2.3 mg/dL), although no differences were observed in triglycerides ( P = .88 for interaction). No significant meal × time interactions were detected in markers of inflammation (C-reactive protein, P = .17; interleukin-6, P = .30) or antioxidant enzymes (superoxide dismutase, P = .77; glutathione peroxidase, P = .36; catalase, P = .32) in the postprandial period. Conclusions: When added to an HFM, acute mango consumption had modest beneficial effects on postprandial glucose and HDL-C responses, but did not alter triglyceride, inflammatory, or antioxidant enzymes.

Consumers prefer watermelon with sweet, red flesh, and the presence of lycopene, citrulline and arginine phytochemicals helpful for human health is an additional bonus. Breeders often select fruit with desirable flesh characteristics based on soluble solids content (Brix) and visual flesh color. Although marker assisted selection (MAS) of flesh traits would advance germplasm selection efficiency, the low heritability of Brix and lycopene content in red fleshed watermelon has hampered marker development. Here we describe the identification of QTLs associated with lycopene content, the amino acids citrulline and arginine, and the content of individual sugar (sucrose, glucose, fructose) in an elite × elite recombinant inbred line (RIL) population. Brix was most highly correlated with total sugars and glucose content, lycopene content was correlated with sucrose content, and citrulline and arginine content showed no correlation. A region on chromosome 5 was associated with sucrose, glucose, and fructose accumulation, while stable arginine content QTLs were identified on chromosomes 2 and 5.

The advanced selections, NCS 10-038 and NCS 10-156, from the North Carolina breeding program were compared to the traditionally used cultivars, Camarosa and Chandler, for storage life and fruit com...

Demand for fresh berry products continues to grow in the United States; however, commercial raspberry production in the southeastern US is difficult because cultivars are not well adapted to the warm climate and fluctuating winter temperatures, where heat degrades plant vigor and fruit quality, and warm spells in mid to late winter can cause low chilling plants to break bud too early. Recent research about the health benefits of a polyphenolic-rich diet has led to a resurgence of interest and breeding efforts in black raspberry, and is the driving factor for this particular research. Two half-sib populations, ORUS 4304 and ORUS 4305 (307 progeny total) were planted in Jackson Springs, North Carolina in 2012. From fall 2012-spring 2015, a number of traits were measured on each plant, among them vigor, winter hardiness, and heat damage, analyzed in several different ways. Plant vigor increased or decreased over harvest seasons based on individual differences in the segregating plant population, but also showed correlations with temperature, i.e., less vigorous plants were more susceptible to damage by heat or cold. Overall, ORUS 4305 was less vigorous than ORSU 4304. As is the case with most raspberries grown in the southeast, vigor in general is expected to decrease over time; however, certain individuals show transgressive segregation for the trait. Linkage mapping for both populations is underway to identify and validate QTL for vigor, winter hardiness, heat tolerance, and other traits within black raspberry. Ultimately, we hope to gain a more complete understanding of black raspberry physiology and genetics to make breeding commercial quality cultivars a possibility in the southeast.

Fruit of organically grown fresh market blackberry cultivars ‘Natchez’, ‘Ouachita’, and ‘Navaho’ harvested at shiny black and dull black ripeness stages were stored at 1 °C for 15 d or at 1 °C for 13 d plus 20 °C for 2 d. Berries were subjectively rated and anthocyanins and phenolic compounds were analyzed by high performance liquid chromatography (HPLC) to determine storage effects on berry postharvest quality and phenolic compounds. Berries harvested at the shiny black ripeness stage or those stored constantly at 1 °C had lower leakage, decay, and softness and a higher overall rating. ‘Navaho’ fruit had generally better storability compared to the other cultivars. Total anthocyanin content was generally higher in ‘Natchez’ and ‘Navaho’ than in ‘Ouachita’, and increased with storage at 20 °C for 2 d, while shiny black and dull black fruit were similar in anthocyanin content. Cyanidin 3-glucoside was found to represent 87–96% of the total anthocyanin content, and cyanidin 3-rutinoside, cyanidin 3-xyloside, and pelargonidin 3-glucoside were also detected. Total phenolic content increased during storage for all cultivars, especially when berries were stored at 20 °C for 2 d. Hydroxybenzoic acids were the primary phenolic compounds identified in fruit tissues of the three cultivars. Content and proportion of cyanidin 3-xyloside and vanillic acid in ‘Natchez’ were significantly lower than in ‘Ouachita’ or ‘Navaho’ fruit. Results indicate that the fruit of blackberry fruit of these cultivars, when grown organically, could be held with acceptable results when harvested at the shiny black stage of ripeness and stored at 1 °C. Transferring fruit to room temperature for as little as 2 d, even after cold storage, decreased marketability. In contrast, phenolic composition differed among cultivars and generally increased with storage.