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BACKGROUND: Achieving a larger berry size accompanied with even ripening are demanded by producers in growing muscadine cultivars. The current study aimed to evaluate the impact of fruit thinning on berry size and quality in two muscadine grape cultivars, 'Triumph' a bronze‐fruited cultivar bearing hermaphrodite flowers, and 'Supreme' a dark black‐fruited cultivar bearing female flowers. Thinning was performed before bunch closure and only one cluster per cane was retained. RESULTS: Results indicated a significant interaction of treatments and cultivars on berry weight and berry diameter. In 'Supreme,' berry weight and berry diameter were significantly increased where thinning was performed, and difference in plant yield between thinned and not thinned vines was not significant. For 'Triumph,' thinning had no significant impact on berry weight and diameter, but yield was ultimately reduced. Other physico‐chemical characters were not affected by fruit thinning. However, differences were observed between both cultivars for these characters. The values of antioxidant scavenging activity (ASA) and total phenolic content (TPC) were 62.7% and 21.7% higher in 'Supreme' as compared to 'Triumph,' irrespective of the thinning treatments. Being a colored cultivar, 'Supreme' berries have higher anthocyanins than 'Triumph,' which has a negligible amount of anthocyanins. The ASA exhibited a strong positive correlation with TPC and anthocyanin content of muscadine grapes. There was also a significant positive correlation between TPC and anthocyanins. CONCLUSION: Cluster thinning of some muscadine grape cultivars may improve individual berry size without affecting overall plant yield or the fruit color, firmness, biochemical attributes and bioactive compounds. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR] more...

BACKGROUND: 'Vegetative' and 'generative' tomato rootstock types have been proposed based on their different effects on tomato scion growth performance; however, their impacts on fruit quality have not been characterized. No study has been conducted in which the effects of rootstock on grape tomato quality attributes were assessed using sensory and instrumental methods of evaluation. Here, we conducted two experiments to examine the influence of 'DR0141TX', 'Estamino', and 'Multifort' rootstocks (vegetative, generative, and uncharacterized, respectively) on fruit quality properties of determinate and indeterminate grape tomato scions under organic production in high tunnels, including color, size, firmness, dry matter content, soluble solids content (SSC), titratable acidity (TA), pH, and consumer sensory attributes. RESULTS: In both experiments, grafting 'Sweet Hearts' indeterminate grape tomato onto 'DR0141TX', 'Estamino', or 'Multifort' increased fruit size and led to negligible effects on sensory attributes and instrumental measurements of fruit quality attributes. For 'BHN 1022' determinate grape tomato, rootstocks did not exhibit any major impact on fruit quality attributes in Experiment 1. However, fruit quality was compromised by grafting per se and rootstocks, especially 'Multifort', in Experiment 2, as reflected by reduced SSC, TA, and SSC/TA and lower scores for overall appearance, overall acceptability, tomato flavor, overall texture, and sweetness. CONCLUSION: In general, 'vegetative' and 'generative' rootstocks showed comparable effects on sensory evaluations and instrumental measurements of grape tomato quality attributes for both indeterminate and determinate scions. More research is needed to better characterize rootstock effects on fruit quality, including the flavor‐related compounds under different growing conditions. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR] more...

BACKGROUND: Tree‐ripe mangoes are of a better quality than the more commonly marketed mature‐green fruit. However, the postharvest life of tree‐ripe mangoes at the chilling threshold temperature for mature‐green fruit of 12 °C is insufficient to allow long distance transport for international marketing. Because the chilling sensitivity often decreases as fruit ripen, lower temperatures (5 and 8 °C) in combination with a controlled atmosphere of 5 kPa O2 plus 10 or 25 kPa CO2 were tested to determine whether the quality of tree‐ripe mangoes could be maintained longer without chilling injury (CI). RESULTS: Tree‐ripe 'Tommy Atkins' and 'Keitt' mangoes were stored for 14 or 21 days, respectively, in air or controlled atmosphere (CA) at 5 or 8 °C. Respiration rates were below 10 mL kg−1 h−1 during CA storage and increased three‐fold during a 3‐day shelf life period at 20 °C. Ethanol synthesis of fruit stored in 25 kPa CO2, but not 10 kPa CO2, increased during storage and remained high during shelf life, indicating physiological stress. Elevated electrolyte leakage and 1‐aminocyclopropane‐1‐carboxylic acid concentrations in both cultivars stored in 25 kPa CO2 also indicated that mesocarp tissues were injured by the higher CO2 level. No CI symptoms were observed in air or CA at either 5 or 8 °C. CONCLUSION: Storage of tree‐ripe mangoes in 5 kPa O2 plus 10 kPa CO2 at either 5 or 8 °C best maintained the quality of Tommy Atkins and Keitt fruit for 14 or 21 days, respectively, without evidence of either atmosphere injury or CI. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR] more...

BACKGROUND Reducing the negative effects of chilling injury (CI) in tomatoes after harvest is essential to ensure good quality and to minimize losses. CI is a postharvest disorder associated with the generation of reactive oxygen species (ROS) in the fruit. Therefore, antioxidant accumulation can counteract ROS, alleviating CI symptoms. In this sense, it has been confirmed that a brief hot‐water (HW) immersion promotes the synthesis of antioxidants. RESULTS: HW treatment at 52 °C for 5 min significantly reduced chilling‐associated decay, from 66.7% to 17.2% in breaker turning (BT) and from 55.8% to 9.8% in mature green (MG) 'BHN‐602' tomatoes stored at 5 °C for 2 weeks and from 26.7% to 6.7% in BT tomatoes stored at 5 °C for 1 week. Also, HW treatment significantly increased lycopene content by 17% in BT tomatoes stored at 5 °C for 2 weeks, as well as ascorbic acid by 11%, lipophilic phenolics by 18% and total phenolics by 6.5% in BT tomatoes stored at 12.5 °C for 1 week. Despite the increase of antioxidants, HW treatment did not enhance the sensory aromatic profile, color and antioxidant capacity. Interestingly, HW treatment reduced ripening time by 3 days in MG tomatoes stored at 5 °C for 2 weeks or at 12.5 °C for 1 week. CONCLUSION: HW treatment applied to MG or BT 'BHN‐602' tomatoes can alleviate the development of some CI symptoms, particularly decay, possibly by increasing antioxidants that scavenge ROS. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR] more...

BACKGROUND: Nitrogen is a key component of crop production and is commonly related to increases in yield and fruit size. The N fertilization rates used for low‐chill peach cultivars were adapted from other peach production regions, where environmental and soil conditions are different. The growth and production as well as the effect on fruit physical and compositional attributes of two low‐chill peach cultivars – 'TropicBeauty' (TB) and 'UFSharp' (UFS) – with five different N fertilization rates (0 (N0), 45 (N1), 90 (N2), 179 (N3) and 269 (N4) kg ha−1 applied each year from 2011 to 2017) were examined. RESULTS: Peach trees under higher N rates had higher pruning weights compared to the lower N0 or N1 rates. Yield was only affected in 2017 for the two cultivars tested. Physical attributes were inconsistently affected by N. Fruit from the higher N rates had lower a* value (more green) than fruit from the trees under low or zero N. While fruit firmness was not affected by N, fruit from trees under zero/low N had higher total soluble solids in some years. CONCLUSION: Considering that N is recycled in the trees, being retained and reused each season to resume growth, it is important to address peach orchard fertilization based on peach tree N status. The results of this experiment show that an increase in N beyond what is required for tree maintenance does not increase yield. In addition, reducing N does not strongly affect fruit quality, although the color and soluble solids results suggest that lower N rates may advance fruit maturation. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR] more...

BACKGROUND The market demand for seedless watermelon has been continuously increasing because of consumer preference. Grafting is a useful tool to manage soilborne diseases in watermelon production, but the use of squash rootstocks may negatively affect watermelon fruit quality. Currently, most research has focused on seeded cultivars, while grafting effects on seedless watermelons remain largely unknown. This multi-season study was conducted to assess the effects of squash rootstocks, including both Cucurbita maxima × C. moschata and C. moschata cultivars, with intact or excised and regenerated roots, on fruit quality of seedless watermelon 'Melody' using both instrumental and sensory measurements under different production scenarios. The grafted watermelon plants were also challenged by field inoculation with Fusarium oxysporum f.sp. niveum. RESULTS A combination of instrumental measurements and consumer sensory analyses suggested that fruit quality of the seedless watermelon 'Melody' was not impacted by the use of the squash rootstocks used in this study, which included soluble solids content, titratable acidity, pH and most fruit sensory properties. Watermelon flesh firmness was increased by grafting but the grafting effect on lycopene content was inconclusive. Root excision and regeneration did not influence the grafting effect, whereas the grafting effect on flesh firmness varied among the rootstocks under Fusarium inoculation. CONCLUSION Overall, grafting with squash rootstocks did not reduce fruit quality attributes of 'Melody' but improved texture. Our results support incorporating grafting into integrated management programs for seedless watermelon production. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR] more...