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Blueberries have a high commercial value on the international market but deteriorate rapidly after harvest, which is caused by high temperature and humidity. In the present work, the effects of high CO2 (25%) were evaluated at 0 °C for 35 days on the quality and Antioxidant capacity (AC) of blueberries (Vaccinium spp.). The results indicated that 25% CO2 treatment significantly delayed the respiration rate and preserved the aroma compounds. Meanwhile, the levels of aldehydes and limonene were enhanced, but esters and ethanol contents were decreased by 25% CO2-treated. In addition, the activity of the enzymes (Peroxidase (POD), Catalase (CAT) and Superoxide dismutase (SOD)) was promoted, while 25% CO2-treated inhibited Ascorbate peroxidase (APX) activity. Simutanously, 25% CO2 increased the accumulation of antioxidants (Total phenolic [TPC], flavonoid, Ascorbic acid [AsA] and Glutathione [GSH]), and the free radical-scavenging capacity (hydroxyl (·OH) and 1, 1-Diphenyl-2-picrylhydrazyl (DPPH)) was also enhanced. This study showed that high CO2 could maintain the quality of blueberries by inhibiting respiration as well as maintaining the aroma and AC. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Ciencias Hortícolas is the property of Revista Colombiana de Ciencias Horticolas 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.)

This paper describes an approach to estimate the photosynthetic capacity and derive the optimum fruit number for each individual tree, in order to achieve a defined fruit size, which is named as the fruit bearing capacity of the tree. The estimation of fruit bearing capacity was carried out considering the total leaf area per tree as measured with a 2-D LiDAR laser scanner, LALiDAR, and key carbon-related variables of the trees including leaf gas exchange, fruit growth and respiration, in two commercial apple orchards. The range between minLALiDAR and maxLALiDAR was found to be 2.4 m² on Pinova and 4.3 m² on RoHo 3615 at fully developed canopy. The daily C requirement of the growing fruit and the associated leaf area demand, necessary to meet the average daily fruit C requirements showed seasonal variation, with maximum values in the middle of the growing period. The estimated fruit bearing capacity ranged from 33-95 fruit tree-1 and 45-121 fruit tree-1 on the trees of Pinova and RoHo 3615, respectively. This finding demonstrates sub-optimal crop load at harvest time in both orchards, above or below the fruit bearing capacity for individual trees. In conclusion, the LiDAR measurements of the leaf area combined with a carbon balance model allows for the estimation of fruit bearing capacity for individual trees for precise crop load management. [ABSTRACT FROM AUTHOR]

In cherry production, the assimilate supply to the fruit is a crucial factor for growth and formation of quality parameters. The assimilate supply per fruit is limited by the relative growth capacity of trees, represented by the leaf area to fruit ratio (LA:F). In the present study, the required leaf area per fruit (LAdemand [cm2 fruit-1]) of two sweet cherry cultivars, 'Bellise' and 'Regina', was estimated in 2018 and 2019, based on measured and interpolated values of fruit growth and fruit respiration rates. LAdemand changed daily with an overall increase during fruit development, showing average values in stage III in 2018 and 2019 of 139 cm2 and 175 cm2 in 'Bellise', while 199 cm2 and 212 cm2 were found in 'Regina', respectively. Estimated LAdemand for both cultivars was compared with measurements in cherries grown on girdled branches. In both years, estimated values exceeded measured values. In both years, positive correlation between LA:F and fresh mass, soluble solids content, and coloration was observed. The data obtained can be applied to evaluate the tree’s crop load for precise management. [ABSTRACT FROM AUTHOR]

This study presents a mathematical model to describe respiration (O2 consumption and CO2 production) and transpiration rates of minimally processed pineapple (cut into slices) as a function of temperature, relative humidity (RH) and geometric configuration. To experimentally adjust suitable models for respiration and transpiration, minimally processed pineapple (Ananas comosus) was stored in slices of three types of configuration (a complete slice with 1 centimeter of thickness, a complete slice with 2 centimeter of thickness and a half slice with 1 centimeter of thickness) at different temperature and RH. To estimate respiration rates, two possible models were compared and the most suitable one was chosen: the O2 consumption and CO2 production were modeled by using a Michaelis-Menten enzyme kinetics and by using a first-order kinetics choosing the former. Throughout the different experiments, the respiration rates were higher by increasing the storage temperature. The transpiration data shows the weight loss is linear for all the samples during the entire storage time. Transpiration was represented by considering the mass transfer (of moisture) due the water activity gradient between the produce and the atmosphere surrounding it, and the water evaporated as a consequence of absorbing the respiratory heat generated in the cut fruits. Results shows a high goodness of fit between experimental data and estimated values with the respiration-transpiration models (R² adj > 0.88). [ABSTRACT FROM AUTHOR]

Mango is produced in tropical zone and consumed around the world. However, mango fruit has a short postharvest life resulting in severe loss during storage. In this study, the effects of heat treatment applied to ivory mangoes on physical, physiological and biochemical quality was studied. The results showed that mangoes subjected to all hot water treatment at 50C - 10 min, 60C - 1 min, 70C - 5 s could improve the quality, while the 60C - 1 min treatment was the optimal method. We found that 60C - 1 min treatment could inhibit the respiration rate, the relative electric conductivity and the malondialdehyde content, and increase the total phenols and flavonoids not reported earlier. Moreover, the activity of polyphenol oxidase, peroxidase and polygalacturonase was reduced, and the activity of catalase was increased, thus maintaining a better quality of ivory mangoes. The 60C - 1 min treatment is the alternative method for improving the quality of ivory mangoes during the storage. [ABSTRACT FROM AUTHOR]

Custard apple, a tropical fruit, is underutilized because of its poor storability. Researchers have worked on various aspects for improving the storage life of fruits; still its storage life is limited to few days. So to counteract this, an experiment was conducted to study the effect of modified atmosphere packaging using three different kinds of films along with low temperature storage at 8, 12 and 15 °C and observations were recorded at weekly interval. The study indicated an increasing trend in the respiration rate and ethylene production rate as well, and the rate increased with increase in storage temperature and duration. The physiological loss in weight in packed fruits showed a drastic reduction. Titratable acidity increased as storage duration while ascorbic acid shown exact reverse trend. There was significant increase in reducing sugar and total sugar as duration increased but rate was low in 8° C fruits. [ABSTRACT FROM AUTHOR]

MAP is a dynamic system where respiration of the packaged product and gas permeation through the packaging film takes place simultaneously. The desired level of O and CO in a package is achieved by matching film permeation rates for O and CO with respiration rate of the packaged product. A mathematical model for MAP of fresh fruits applying enzyme kinetics based respiration equation coupled with the Arrhenious type model was developed. The model was solved numerically using MATLAB programme. The model was used to determine the time to reach to the equilibrium concentration inside the MA package and the level of O and CO concentration at equilibrium state. The developed model for prediction of equilibrium O and CO concentration was validated using experimental data for MA packaging of apple, guava and litchi. [ABSTRACT FROM AUTHOR]

To investigate the impact of locality and orchard management on fruit quality, ‘Samar Bahisht Chaunsa’ fruit harvested from two commercial orchards were stored at 11°C and 80%–85% RH for 4 weeks. Physical fruit quality, fruit rot, and disorders were not influenced by locality. However, at the ripe stage, fruit harvested from orchard-1 exhibited reduced respiration rate (5.84 mmole kg−1h−1), higher peel color (3.35), pulp color (7.33), aroma (6.66), taste (7.33), flavor (7.33), SSC:TA ratio (139.1), reducing (4.06%), non-reducing (10.38%), and total sugar (14.99%) contents. In conclusion, quality of mango fruit following cold storage is significantly influenced by locality and orchard management. [ABSTRACT FROM AUTHOR]

The changes in abscissic acid (ABA) and jasmonic acid (JA) contents during fruit development of dragon fruit (Hylocereus undaatus) were determined. Associated changes in respiration, 1-aminocyclopropane-1-carboxylic acid (ACC) contents, and sugar levels were also measured. ACC content and respiration rate were high at early fruit development stages and gradually decreased as the fruit matured and ripened. In the pulp, ABA content increased before the increase in glucose and fructose contents. JA contents in the peel and pulp were high at the immature stage and decreased toward maturation. The results indicate that dragon fruit is non-climacteric and that JA may have a role in cell division in the developing fruit while ABA may induce fruit maturation. [ABSTRACT FROM AUTHOR]

The effect of heat pre-treatment (45 °C/25 min), applied to whole fruit, and post-cut calcium dips in 1 and 2 g/L CaCl solutions on respiration rate and texture preservation of kiwifruit slices was studied. During a 9-day period, packages' atmosphere composition, slices' firmness, pectin content and sensory scores were evaluated. Histological observations of samples were also performed. Neither heat pre-treatment nor calcium dips alone were effective in diminishing respiration rate of the slices but the application of both treatments revealed a synergistic effect on respiration rate reduction. Calcium-dipped fruit slices showed better firmness preservation. Post-cut calcium dips, alone or combined with heat pre-treatments, yielded slices presenting higher insoluble/total galacturonic acid ratio, indicating formation of calcium pectates. Slices from heat-pre-treated fruits, even in the absence of calcium, also revealed insoluble/total galacturonic acid ratio similar to calcium-treated slices, supporting, despite the lower firmness value, a more structured tissue, as observed in SEM microphotographs. Sensory and physical-chemical parameters obtained were correlated. The effectiveness of calcium treatment was equally observed for both tested concentrations during a 9-day shelf life period. [ABSTRACT FROM AUTHOR]

‘Malindi’ banana (Musa,‘Dwarf Cavendish’) was stored at three storage conditions (11–12°C and 95.5% RH; 20–22°C and 82–85% RH; and cyclic cooling and warming to simulate day/night conditions during the banana harvest season: 28°C and 50% RH/18°C and 70% RH). Fruit storage life was 21, 10, and 8 days in the refrigerated storage, normal room storage, and storage under cyclic day/night conditions, respectively. Fruit ripening, respiration, and ethyelene production were significantly higher at high temperature storage and cyclic day/night conditions leading to faster fruit deterioration. Under these storage conditions, the rate of fruit weight loss, firmness, vitamin C loss, and chlorophyll degradation was also higher compared to refrigeration. [ABSTRACT FROM AUTHOR]

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An experimental hyperbaric system was designed and built to explore the effect of hyperbaric treatment on the respiration rate (RR) and respiratory quotient (RQ) of tomato. It consists of five containers that can be individually pressurized from 1 to 9 atm. The respirometer was equipped with a flow meter, control valve, pressure transducer, CO and O gas analyzer, and type T thermocouples that are all connected to a data acquisition and control card. A software interface was programmed to allow control of the air flow rate through the proportional valve of the flow meter based on a proportional-integral-derivative algorithm system. Hyperbaric treatments have been performed on tomato fruit, and it was observed that RR was inversely proportional to pressure. [ABSTRACT FROM AUTHOR]

Understanding the effect of time and temperature on the respiration rate (RR) of fresh-cut produce, towards the design of a suitable modified atmosphere packaging (MAP) system, requires an adequate mathematical model for prediction of RR as a function of both time and temperature. This study investigated the effect of temperature (5, 10, and 15 °C) and storage time (1 to 5 d) on the RR ( and ) of 2 pomegranate cultivars (cv. ``Acco'' and ``Herskawitz'') fresh arils. and were 3 to 4 folds significantly higher with increased temperature from 5 to 15 °C and were within the range of 2.51 to 7.59 mL/kg h and 2.72 to 9.01 mL/kg h, respectively, for both cultivars. At 15 °C increased significantly from 8.4 to 25.96 mL/kg h from day 1 to 5, respectively, while at 5 °C changed from 2.9 to 2.05 mL/kg h from day 1 to 5. Temperature had the greatest influence on RR and the interaction of time and temperature also significantly affected and . The respiratory quotient (RQ) estimated by linear regression was 0.98 at 95% significant level. The dependence of RR on temperature and time was accurately described with a combination of an Arrhenius-type and power equation model for and of fresh pomegranate arils. Practical application: Predicting the respiration of fresh and fresh-cut produce is important in designing postharvest handling systems. Mathematical models to predict respiration rates of pomegranate fresh arils have been developed taking into account the effects of storage time and temperature. These models have practical application in designing modified atmosphere packaging to maintain quality and shelf life of pomegranate arils. [ABSTRACT FROM AUTHOR]

This study, as a preliminary step toward the definition of a carbon budget model for pistachio trees (Pistacia vera L.), aimed at estimating and evaluating the dynamics of respiration of vegetative and reproductive organs of pistachio tree. Trials were performed in 2005 in a commercial orchard located in Sicily (370 m a.s.l.) on five bearing 20-year-old pistachio trees of cv. Bianca grafted onto Pistachio terebinthus L. Growth analyses and respiration measurements were done on vegetative (leaf) and reproductive (infructescence) organs during the entire growing season (April–September) at biweekly intervals. Results suggested that the respiration rates of pistachio reproductive and vegetative organs were related to their developmental stage. Both for leaf and for infructescence, the highest values were observed during the earlier stages of growth corresponding to the phases of most intense organ growth. The sensitivity of respiration activity to temperature changes, measured by Q10, showed an increase throughout the transition from immature to mature leaves, as well as during fruit development. The data collected were also used to estimate the seasonal carbon loss by respiration activity for a single leaf and a single infructescence. The amount of carbon lost by respiration was affected by short-term temperature patterns, organ developmental stage and tissue function. [ABSTRACT FROM PUBLISHER]

Copyright of Erwerbs-Obstbau is the property of Springer Nature 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.)

Research was conducted to understand the effect of harvesting method and postharvest temperature on fruit quality of 'Brightwell' and 'Tifblue' rabbiteye blueberries (Vaccinium ashei Reade). Mass loss, firmness and fruit respiration were measured under refrigerated (1°C) and ambient (22°C) conditions for both machine harvested (MH) and hand harvested (HH) berries of each cultivar. Few differences were found between cultivars for the various postharvest quality parameters. Firmness ofMHblueberries was diminished by an overall average of 36.2% as compared to HH berries. MH berries placed at 22°C had a mass loss rate of 2.6% per day as compared to 0.2% per day at 1°C during the first two days of storage. Respiration rate ofMHberries at ambient temperature was 31.1% higher than HH berries. Refrigeration reduced respiration rates by an overall average of 79%. Refrigerated HH blueberries had the best overall fruit quality after storage, and firmness measures suggested that HH berries had an extended shelf-life of about one week as compared to MH berries. Thus, MH and HH fruit differ in their postharvest handling needs. Also, multiple quality measures are valuable in more clearly assessing fruit storage life. [ABSTRACT FROM PUBLISHER]

We estimated translocatory balance in fruit of the tropical tree Durio zibethinus Murray on the basis of a compartment model. Rates of fruit respiration, dry weight growth and translocation increased with time. Over the 8.2 weeks of fruit development, the relative distribution of translocation was 80% to dry weight growth and 20% to respiration. The ratio of respiration rate to translocation rate, which ranged from 14 to 32%, tended to decrease with time, whereas the ratio of dry weight growth rate to translocation rate, which ranged from 68 to 86%, tended to increase with time. The relationship between dry weight growth rate and translocation rate was fitted by a power function, where dry weight growth rate was statistically proportional to translocation rate. The relationship between respiration rate and translocation rate was formulated by a smooth curve, where respiration rate increased as translocation rate increased. Examination of these ratios with respect to the translocation rate indicated that the dry weight growth rate/translocation rate ratio increased slightly with increasing translocation rate, whereas the respiration rate/translocation rate ratio decreased with increasing translocation rate. A comparative analysis of these results with those obtained for Cinnamomum camphora (L.) J. Presl revealed a lower ratio of translocation to dry weight growth in D. zibethinus than in C. camphora, indicating that D. zibethinus fruits have a low translocatory efficiency. [ABSTRACT FROM AUTHOR]

The rates of dry weight increase and respiration of fruits were measured throughout fruit ontogeny at 20, 25 and 30°C in cucumber (Cucumis sativus L. cv. Corona). By maintaining one or five fruits per plant, which strongly affected fruit dry weight but not ontogeny, the effects of fruit size and ontogeny on respiration could be studied separately. The respiration rate per fruit followed a sigmoid curve during fruit ontogeny, while the specific respiration rate (respiration rate per unit dry weight) declined with time after anthesis. The specific respiration rate was almost linearly related to the relative growth rate. The specific respiratory costs for both growth and maintenance were highest in young fruits, but were not affected by fruit size. The average specific respiratory costs for growth and maintenance at 25°C were 3.3–3.9 mmol CO2 g-1 and 4.0 nmol CO2 g-1 s-1, respectively. An increase in temperature had no effect on the specific respiratory costs for growth, while the costs for maintenance increased with a Q10 of about 2. The costs for growth agreed reasonably well with theoretical estimates based on the chemical composition of the fruits but not with estimates based on only the carbon and ash content. The respiratory losses as a fraction of the total carbon requirement of a fruit changed during fruit ontogeny, but were independent of temperature and were similar for slow- and fast-growing fruits. The cumulative respiratory losses accounted for 13–15% of the total carbon requirement. [ABSTRACT FROM AUTHOR]

Weekly measurements of fruit growth, fruit respiration and shoot extension growth were made in the field on early (June Lady) and late (O'Henry) maturing cultivars of peach (Prunus persica L. Batsch). The seasonal patterns of fruit growth and respiration for the two cultivars were very similar except that the early maturing cultivar bloomed a few days earlier than the late cultivar and had a shorter intermediate stage (Stage II) of fruit growth. Maximum rates of fruit respiration per unit weight at 20°C were similar for both cultivars during the first two stages of fruit growth but higher for the early cultivar during the final stage of fruit growth. Maximum fruit growth rates within any particular stage of fruit growth were similar for both cultivars, but the mean fruit weight of the late cultivar was greater at the end of Stage 11, because of the extended length of this stage compared to the early cultivar. The final stage of most rapid fruit growth and respiration coincided with the period of most rapid shoot extension growth in the early maturing cultivar but occurred after this period in the late maturing cultivar. Genetic selection for early fruit maturity in peach has apparently had little effect on timing of shoot growth and this may result in increased competition between vegetative and reproductive sinks during peak periods of fruit growth in early maturing cultivars. [ABSTRACT FROM AUTHOR]