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Lettuce (Lactuca sativa L.) is grown worldwide, from temperate to subtropical climates. Spring season production in humid, subtropical regions, such as southern Florida, is characterized by rising ambient temperatures that can stress lettuce to prematurely bolt and lose shelf life. The objectives of this research were 1) to identify genetic variability in heat tolerance and shelf life among lettuce types and accessions grown under humid, subtropical conditions, and 2) to understand the genotype × environment (G × E) interaction to estimate shelf life of these lettuce accessions. Five lettuce types (romaine, crisphead, butterhead, leaf, and Latin) were grown under commercial conditions in the Everglades Agricultural Area near Belle Glade, FL, USA, for five field experiments over two seasons. Lettuce heads were evaluated at harvest, and subsets were transported to a local commercial grower/shipper for vacuum-cooling and storage at 15 °C according to previously determined protocols for accelerated shelf life testing. Visual appearance ratings were made across harvests and storage time points to segregate lettuce accessions with an estimated marketable shelf life >14 days. The breeding lines tested in this research had head weight and marketability comparable to commercial cultivars. Notably, the crisphead accessions 50113, 60157, 60159, and H1098 had the highest estimated and actual shelf life of more than 21 days, with no presence of bolting or tipburn. Meanwhile, romaine, butterhead, leaf, and Latin types had accessions with estimated and actual shelf life ranging from 14 to 28 days and no presence of bolting or tipburn. A G × E analysis indicated that this interaction is significant; therefore, breeders should consider analyzing G × E when developing new cultivars with good horticultural characteristics, longer shelf life, and most importantly, adaptation to warmer humid, subtropical conditions.

The postharvest loss in quality of grapefruit during storage can be quantified by determining the change of the quality traits of grapefruit, including total soluble solids (TSS), titratable acidity (TA), TSS/TA, weight loss (WL), and the development of decay (DC) and chilling injury (CI). The objective of this study was, therefore, to develop models that encompass the relationship between both storage conditions and duration and the quality traits of grapefruit to predict the loss of grapefruit quality during storage. The models of TSS, TA and TSS/TA were developed with experimental data collected during the 2007–08 and 2008-09 growing seasons that were obtained from the literature. The models for WL, DC, and CI were developed with experimental data collected in Florida during the 2004–05 and 2005-06 growing seasons. The WL, DC and CI models were applied to determine storage life. The results indicated that there was a second-order polynomial relationship between storage duration and TSS and linear relationships between storage duration and TA and TSS/TA. A longer storage duration resulted in a higher TSS, a lower TA and a higher TSS/TA. There were linear relationships between storage duration and WL, thermal time above a threshold temperature of 0 °C and DC and thermal time below 10 °C and CI, with higher WL, DC and CI resulting from longer storage duration and larger number of thermal times. Model performance for simulating TSS, TA, TSS/TA for storage temperature between 2 °C and 11 °C was good. There is good performance for simulating WL for storage temperature between 4 °C and 12 °C, DC for storage temperature of 21.1 °C, and CI for storage temperature of 4.4 °C. Following model development, it was applied to determine the optimum storage life. Optimum storage condition was a storage temperature of 7.6 °C for approximately 20 d, resulting in less than 5 % of the stored fruits lost due to unacceptable quality based on predictions for WL, DC and CI.

Persimmons (Diospyros kaki) are known for their sweet and flavorful taste. They are native to Asia, specifically China, and were first grown in Florida in the 1870s. Persimmons are still not as popular in the United States as other fruits, but interest has been growing in recent years. Persimmon fruit are generally classified into astringent and non-astringent types. Astringent varieties can have adverse health effects caused by tannins and must be fully ripe (soft) or artificially treated to remove astringency. Drying is a common method to preserve and extend the shelf life of persimmons while also enhancing the flavor, color, and nutritional value of persimmons. There are different methods to dry persimmons, including traditional and modern methods.

Peach (Prunus persica L. Batsch) is a valuable temperate fruit from the Rosaceae family, which also includes many other commercially important fruits such as apples and pears, apricots, cherries and plums, and blackberries, raspberries and strawberries. Peaches are known for being a rich source of bioactive compounds, including flavonoids, anthocyanins, carotenoids, phenolic compounds, and vitamins, as well as possessing a high antioxidant activity, all of which are associated with various health benefits. Furthermore, consumers greatly value high-quality peaches due to their exceptional nutritional value and enjoyable sensory attributes. This publication aims to familiarize growers, Extension agents and specialists, and the public with insight into drying methods of peach fruit, including freeze-drying and dehydration, that can extend shelf life of this commodity for year-round enjoyment.

Pink rib discoloration or pinking in the midribs of lettuce (Lactuca sativa) leaves is a stress-induced disorder that leads to crop loss worldwide. Maintaining recommended field and postharvest conditions reduces its incidence but does not eliminate the issue. During the past decade, research has identified the tolerance of this disorder among lettuce types and cultivars grown in cooler climates. However, tolerance to pink rib among lettuce types grown in humid subtropical climates is unknown; therefore, it is necessary to screen lettuce germplasm under these growing conditions. During this study, diverse lettuce accessions were planted for early-season, mid-season, and late-season harvests over two seasons in Belle Glade, FL, USA. Harvested midribs were wounded to induce pink rib, stored for 6 to 9 days at 5 °C and >95% relative humidity, and rated for severity using a 5-point subjective scale. Genotype × environment interactions were evaluated to understand the environmental factors that favor the development of pink rib during storage and between planting seasons. Pink rib severity increased during storage, with the highest increase observed after 3 to 4 days in both seasons. After 9 days of storage, lettuce accessions with the least pink rib for each leaf type were identified. The lowest pink rib ratings after 9 days of storage were “moderate” (rating of 3) for crisphead, Latin, and romaine, “slight” (rating of 2) for butterhead types, and “none” (rating of 1) for leaf types. Additionally, pink rib severity increased among accessions during the late spring season harvest when field temperatures were higher and daylight hours were extended. The lettuce germplasm with low susceptibility to pink rib is promising to breed lettuce lines for future research.

Grapefruit are well-adapted to arid and warm climatic conditions, but well-irrigated trees usually produce better-quality fruits. Because water is a major component of the fruits, there is a strong relationship between drought stress and fruits quality traits such as fruits size, external fruits color, and juice quality. The object of this study was to develop a computer model to predict postharvest external grapefruit color as a function of drought stress. During model development, drought stress was quantified using a concise water balance model based on crop evapotranspiration, precipitation, and irrigation. Data collected from Murcia, Spain, during the 2007 and 2008 growing seasons were used for model development, and the model was optimized by comparing model predictions and observations for each growing season. The root mean square error and Nash and Sutcliffe coefficient of efficiency (NSE) were used to evaluate model performance. Then, the model was evaluated with independent data collected from Florida during the 2005–06 growing season. A second-order polynomial relationship was found between external fruits color and drought stress, with less drought stress resulting in better external fruits color. Model optimization revealed good model performance for predicting external fruits color in Murcia, with NSE values of 0.975 and 0.979 for the 2007 and 2008 growing seasons, respectively. Model evaluation with the data from Florida showed that model predictions were reliable, with a NSE value of 0.984. A robust model to predict external grapefruit color as affected by drought stress was developed during the present study and could be potentially applied to supply information for suitable irrigation management of various grapefruit cultivars grown under different climatic conditions. Model performance could be confirmed by future research with data collection during further multiple seasons for different cultivars and a range of climatic conditions.

Muscadine grape (Muscadinia rotundifolia [Michx.]) is a fruit crop native to America; it adapts well to a wide range of biotic and abiotic stresses and have thus been grown and vinified throughout the southeastern US for centuries. Currently, southeastern farmers grow approximately 5,000 acres of almost 100 improved muscadine-grape varieties for commercial use. Recent research demonstrated the fruit’s significant contribution of beneficial phytochemicals to the typical American diet; and thereafter, the demand for muscadine grapes considerably increased. Its thick peels and seeds, though, have prevented wider public consumption. This publication aims to introduce growers, Extension agents/specialists, and the general public to the potential for a new, value-added product that makes muscadine grapes much easier to eat and may diversify the food processing industry.

Stonefruit grown commercially in Florida include peaches, nectarines, and plums. This publication is directed to current and potential stonefruit growers, handlers, and marketers, as well as researchers, extension agents, students, and consumers. It provides information about the Florida stonefruit industry, stonefruit cultivars that are suitable for Florida, stonefruit postharvest physiology and pathology, fruit quality, and recommended postharvest handling and marketing practices.

Storage at the putative chilling threshold temperature (CTT) to avoid chilling injury still limits postharvest handling of tropical fruit like banana in that ripening may occur at the CTT. To determine whether chilling injury (CI) symptoms would develop in mature green (MG) banana fruit if the CTT exposure was extended by inhibiting ethylene action and thus ripening, 1-methylcyclopropene (1-MCP) was applied. Individual ‘fingers’ from multiple ‘clusters’ of MG bananas were either immersed in water or 50 μg L−1 1-MCP (a.i.) solution and each treatment was divided into three subgroups for storage at 5.0°C (severe CI), 13.0°C (mild CI), or 14.0°C (CTT) ± 0.1°C. 1-MCP delayed ripening in terms of color change for 10 days for fruit stored at the CTT. Ethylene production by fruit at 5.0°C remained around 0.04 ng kg−1 s−1 with no obvious increase during 31-day storage. Ethylene production at 14.0°C (−1-MCP/+1-MCP) increased on Day 33 while increasing on Day 38 for 13.0°C fruit without 1-MCP and on Day 39 for fruit with 1-MCP. Peak climacteric ethylene occurred on Days 44 and 39 for 13.0 and 14.0°C fruit without 1-MCP, respectively, and on Days 59 and 51 for 13.0°C and 14.0°C 1-MCP-treated fruit, respectively. As hypothesized, longer exposure of MG banana fruit to the CTT of 14.0°C without onset of ripening as was allowed by prior 1-MCP treatment allowed CI to develop at that normally non-chilling temperature. Vascular browning was the first visual and most sensitive CI symptom in the experiment and was observed on Day 4 at 5.0°C, Day 10 at 13.0°C, Day 19 at 14.0°C without 1-MCP, and on Day 28 at 14.0°C with 1-MCP. Using a 1-MCP pre-treatment to remove the influence of ethylene from bananas stored at 13°C or 14°C also resulted in slight reduction in vascular browning severity. In conclusion, a putative safe temperature may become a CI temperature if the shelf-life-limiting factor is removed, allowing longer exposure. Chilling at the CTT caused relatively mild injury on fruit, and vascular browning is a sensitive indicator of CI status, while the light-adapted quantum yield of photosystem II [Y(II)] could be a non-destructive indicator of early CI stress in MG banana. Fruit at 13.0/14.0°C developed CI symptoms slightly later with 1-MCP than without 1-MCP. This suggests that ethylene might be involved in early CI symptom development.

The postharvest life of lettuce (Lactuca sativa) is variable and negatively affected by mechanical injury, incomplete cooling, and poor genetic quality. Lettuce breeders are developing cultivars with a longer shelf life and rely on subjective, destructive, and time-consuming methods for quality analysis. One method of accelerating quality evaluations is known as accelerated shelf-life testing (ASLT), which has the potential to assist breeders in assessing lettuce quality and shelf life. The objective of this research was to determine the quality traits that significantly affect shelf life to develop an ASLT procedure to rapidly assess the postharvest quality of lettuce accessions in breeding programs. In Test 1, Romaine lettuce quality was evaluated using one subjective and five objective parameters during storage at 5, 10, 15, or 20 °C. Results determined that weight loss, lightness*, and hue* angle were best correlated with the overall appearance rating, whereas storage at 10 or 15 °C differentiated the shelf-life potential quickly and without excessive deterioration. In Test 2, these objective characteristics and storage temperatures were used to study rates of quality deterioration of a commercial Romaine cultivar (Okeechobee) and a breeding line (60182), both with long shelf lives, and a Batavia lettuce cultivar (La Brillante) with a short shelf life. Lettuce was evaluated during storage at 10 °C (winter and spring seasons) or at 15 °C (winter season). Weight loss was the most appropriate quality index for lettuce at these storage temperatures for a single harvest, whereas lightness* and hue* angle were the most appropriate indices for comparing quality between harvests. To apply ASLT to postharvest assessments of lettuce, breeders and other researchers should include two controls with good and poor shelf life (similar to ‘Okeechobee’ and ‘La Brillante’, respectively) as standard baseline cultivars during storage at either 10 or 15 °C.

This study investigated the effect of ethylene treatment at high temperatures of 30 to 40 °C for up to 72 hours on subsequent ripening-associated processes in mature green ‘Sunny’ and ‘Agriset 761’ tomatoes (Solanum lycopersicum). Compared with ethylene-treated fruit at 20 °C, ethylene exposure at 30 or 35 °C stimulated ripening in terms of ethylene biosynthesis and color development, but the ethylene effect was only apparent after transfer to air at 20 °C. There were no negative effects on ripe tomato quality related to ethylene exposure at 30 or 35 °C. However, ethylene production of tomatoes was permanently impaired by ethylene exposure at 40 °C for 48 or 72 hours even after transferring fruit to air at 20 °C; these fruit exhibited slow softening and color development. Our results suggest that tomatoes perceive ethylene at 30 to 35 °C despite impairment of ripening at those temperatures, with the accelerated ripening response becoming apparent only after transferring the tomatoes to air at lower temperature.

Florida peaches (Prunus persica) typically are picked and placed in a cold room on the day of harvest, then packed and shipped the next day. This room cooling (RC) is slow, requiring ≈24 hours or more for the fruit to reach optimal temperature (6 to 7 °C). There is currently limited research on the effect of cooling practices on microbial quality of peaches, yet this study is essential for decision making in areas such as upgrading packing house facilities and the implementation of improved handling procedures. This research compared the efficacies of postharvest cooling by RC, forced-air cooling (FAC), and hydrocooling with sanitizer (HS) treatment of peaches to reduce their surface microbial population and to determine the effect on shelf life and microbial quality. Three trials for RC and two trials each for FAC and HS were performed. Following cooling, fruit were stored at 1 °C. The average aerobic plate count (APC) from field samples was 5.29 log cfu/peach, which remained unchanged after RC or FAC but was reduced significantly (P < 0.05) to 4.63 log cfu/peach after HS. The average yeast and mold counts (Y&M) from field samples (6.21 log cfu/peach) were reduced highly significantly (P < 0.001) to 4.05 log cfu/peach after HS. Hydrocooling significantly (P < 0.05) reduced the APC and Y&M counts from the peaches and showed promise in maintaining the microbiological quality of the fruit throughout storage. However, at the end of the 21-day storage period, there was no significant difference in APC or Y&M counts from peaches, irrespective of the cooling methods. Peaches that went through the hydrocooling process and were subsequently packed showed an increase (P < 0.05) in both APC and Y&M counts, while fruit that were not hydrocooled showed no such increase. Information obtained will be used to recommend the best temperature management practices for maintaining the postharvest quality of peaches. A detailed cost-benefit analysis of different cooling methods and the time interval between harvest and shipment are both necessary for a more conclusive recommendation.

Broccoli is a highly perishable crop, due to its high respiration rate, and rapidly loses quality under inappropriate handling temperatures. The objective of this study was to evaluate the effect of commercial hydrocooling (HY), forced-air cooling (FA) or slushed-ice cooling (SI) on the quality and shelf-life of two commercial broccoli cultivars (‘Marathon’ and ‘Eastern Crown’) grown in northeast Florida during the early spring season. Following HY and FA, individual bunches (‘Marathon’) or crowns (‘Eastern Crown’) were placed in plastic film bags and stored at 1 °C for 7 days then transferred to 5 °C for 8 days to simulate retail conditions. It was found that HY removed the field heat 3.6 and 4.8 times faster than FA and SI, respectively. For both cultivars, using a texture analyzer, broccoli cooled by SI were softer (20.4 to 27.9 N) with higher head deformation than those by HY or FA (45.6 to 58.9 N) after 15 days of storage. Overall appearance of both cultivars decreased during storage if infected in the field by the fungal pathogen Alternaria brassicicola, which causes black spot disease. However, by the end of storage ‘Eastern Crown’ had a higher quality rating (6.2) than ‘Marathon’ (5.4). Broccoli floret moisture content was not affected during storage; however, ‘Marathon’ had higher moisture content (94.7%) than ‘Eastern Crown’ (89.2%). Yellowing was expressed more for ‘Marathon’, which had higher chroma* value (21.4) and lower hue* angle (h*) (122.3) value than ‘Eastern Crown’ after 7 days at 1 °C, plus 8 days at 5 °C. Carotenoid content was similar for both cultivars at harvest (2.3 mg/100 g) then decreased 39% for ‘Marathon’ and 12% for ‘Eastern Crown’ by day 15. Total chlorophyll was similar for both cultivars throughout storage (22.6 mg/100 g). Ascorbic acid decreased for both cultivars during storage but was higher in ‘Eastern Crown’ (92.0 to 101.9 mg/100 g) compared to ‘Marathon’ (80.7 to 88.6 mg/100 g). Hydrocooling and forced-air plus overwrapping have potential to reduce cooling costs during commercial handling.

Datil hot pepper (Capsicum chinense) has potential for increased production due to its unique, spicy flavor and aroma. However, few reports have been published related to postharvest handling characteristics. The purpose of this study was to determine the effect of harvest maturity on fruit quality under simulated commercial storage conditions. ‘Wanda’ datil pepper plants were grown hydroponically under protected culture. Fruit were harvested at yellow and orange maturity stages, placed in vented clamshell containers, and stored at 2, 7, or 10 °C for 21 days. Peppers harvested at yellow stage maintained greater quality than orange peppers during storage at all temperatures. Marketable fruit after 21 days for peppers harvested at the yellow stage was 94% (2 °C), 88% (7 °C), and 91% (10 °C); that for orange-stage peppers was 68%, 74%, and 82% for the same respective temperatures. No chilling injury (CI) symptoms were observed in these tests. Initial pepper moisture content was 90%, decreasing only slightly during 21 days of storage; weight loss ranged from 2% to 8%. Soluble solids content (SSC) was greater for peppers harvested at the orange stage (9.5%) than for those at yellow stage (7.8%). Neither harvest maturity nor storage temperature affected total titratable acidity (TTA; 0.13%) or pH (5.3). Respiration rate varied with temperature but not by harvest maturity and ranged from 12 to 25 mg·kg−1 per hour after 8 days of storage. Peppers harvested orange contained double the amount of total carotenoids as yellow fruit. Carotenoid content for yellow and orange peppers was 58 and 122 µg·g−1, respectively. Capsaicinoid content ranged from 1810 to 4440 µg·g−1 and was slightly greater for orange-harvested peppers. Datil peppers harvested at the yellow stage and stored in vented clamshell containers had better quality than peppers harvested at the orange stage after 21 days at 2 °C.

Cooling procedures used by blueberry (Vaccinium sp.) growers often may include delays up to 24 hours that can damage the fruit through rough handling and adverse temperatures, thereby potentially compromising quality and, subsequently, safety. The objectives of this experiment were to compare forced-air cooling (FAC) compared to hydrocooling without sanitizer (HW) and hydrocooling with sanitizer (HS) regarding the quality and shelf life of southern highbush blueberry [SHB (Vaccinium corymbosum)] and to determine the efficacy of these treatments for reducing Salmonella in SHB. Freshly harvested SHB that were inoculated with a five-serovar cocktail of rifampin-resistant Salmonella were rapidly chilled by FAC or hydrocooling (HW and HS) using a laboratory model system. FAC did not show any significant reduction (P > 0.05) in Salmonella or in the effects on the microbiological quality of blueberries. HW and HS reduced Salmonella by ≈2 and >4 log cfu/g SHB, respectively, on day 0. These postharvest treatments were also evaluated for their ability to help maintain fruit quality throughout a storage period of 21 days at 1 °C. Hydrocooling (both HS and HW) provided more rapid cooling than FAC. Hydrocooled blueberries showed significant weight gain (P < 0.05), whereas FAC resulted in a slight, but insignificant (P > 0.05), reduction in final weight. The results of hydrocooling, both HS and HW, shown in this study could help to extend the shelf life while maintaining or increasing the microbiological quality of fresh market blueberries. Information obtained by this study can be used for developing the best temperature management practices to maintain the postharvest safety and quality of blueberries.

. High CO2 atmospheres have been reported to be accountable for slower ripening processes of many fruit species. In modified or controlled atmosphere storage of mangoes (Mangifera indica L.) delayed ripening is attributed to the effects of CO2 on ethylene biosynthesis, which is reduced under CO2 concentrations beyond 10%. In the present work the objective was to determine if those elevated CO2 atmospheres on ethylene synthesis could be attributed to the action of CO2 upon ACC oxidase. Mature green or tree ripe `Tommy Atkins` mangoes were, in four experiments, held in a flow through system of either 10 or 25% CO2 mixed to 5% O2 or only air for 14 or 21 days at 5, 8 or 12°C. Mangoes in the 25% CO2 atmosphere did not produce detectable levels of ethylene, whereas under 10% CO2 the production rates were significantly suppressed at 5 or 8°C. However, 1-aminocyclopropane-1-carboxylic acid (ACC) concentrations in mango mesocarp tissue at retrieval from storage were similar to the air controls and ACC synthase activity was not completely inhibited. The direct effects of CO2 concentrations on ACC oxidase activity is to be considered the most important factor in inhibiting ethylene biosynthesis of mangoes under 25% CO2 atmospheres.

Mejorar la calidad y laconsistencia de los frutos frescos de mangos que están disponibles para los consumidores en los Estados Unidos de Norteamérica es un importante objetivo del National Mango Board (NMB). El National Mango Board financió el proyecto: “Monitoreo y Evaluación de la Cadena de Suministro del Mango para mejorar su Calidad”, el cual se denominó Proyecto de Calidad del Mango, el cual fue conducido de Diciembre 2007 a Abril de 2009 para identificar los problemas que impiden el que se puedan lograr estos objetivos de manera exitosa. El producto final del Proyecto de Calidad de Mango es este Manual sobre las Mejores Practicas para la Cosecha y el Manejo de los Mangos Comercializados en los Estados Unidos de Norteamérica. Este manual incluye los procedimientos de control de calidad a ser utilizados cuando se monitoree la madurez y calidad en las operaciones comerciales en cuanto al manejo de los frutos de mangos. El manual de 73 páginas se puede descargar haciendo 'clic' en el ícono de PDF ubicado en la esquina superior izquierda, o haga 'clic' aqui.

Improving the quality and consistency of the fresh mangos that are available to consumers in the United States is an important goal of the National Mango Board (NMB). The NMB-funded project, Monitoring and Evaluation of the Mango Supply Chain to Improve Mango Quality (referred to hereafter as the Mango Quality Project), was conducted from December 2007 through April 2009 to identify impediments to successfully meeting that goal. The final deliverable of the Mango Quality Project is this best management practices manual for harvesting and handling mangos marketed in the U.S. The manual includes quality-control procedures to use when monitoring the maturity and quality of mangos in commercial handling operations. The 77-page manual (10 MB pdf), written in Portuguese, was most recently revised in October 2020. The English version is available at https://edis.ifas.ufl.edu/hs1185.

Improving the quality and consistency of the fresh mangos that are available to consumers in the United States is an important goal of the National Mango Board (NMB). The NMB-funded project, Monitoring and Evaluation of the Mango Supply Chain to Improve Mango Quality (referred to hereafter as the Mango Quality Project), was conducted from December 2007 through April 2009 to identify impediments to successfully meeting that goal. The final deliverable of the Mango Quality Project is this best management practices manual for harvesting and handling mangos marketed in the US. The manual includes quality-control procedures to use when monitoring the maturity and quality of mangos in commercial handling operations.

Pathogens are present in all tomato production areas and are most numerous when the weather becomes warm and wet. Movement of weather fronts or tropical storms through production areas can also affect the susceptibility of tomato fruit to decay. Fruit decays can be minimized by the employment of strict sanitation measures along with careful handling. This bulletin is designed to supplement field scouting and identification guides by a) describing postharvest decay pathogens important to Florida tomato packers and shippers, b) presenting sanitation guidelines for controlling decay pathogens during harvest and handling operations, c) offering appropriate storage temperature options.

Optimizing nitrogen (N) input rates for vegetable production is crucial in Florida to reducing production costs and enhancing environmental sustainability. Asian vegetables emerging and expanding in Florida not only increase profit for growers, but also enhance food diversity for consumers. The objective of this study was to gain a better understanding of the partitioning and usage of N and carbohydrates in two Asian vegetable crops: long bean (Vigna unguiculata ssp. sesquipedalis (L.) Verdc.) and angled luffa (Luffa acutangular (L.) Roxb.). Four N rates (0, 0.91, 1.36, and 1.81 g N pot−1) were compared in a high tunnel trial to understand the influence of N fertilization on the two crops. For long bean, plant biomass was highest at the highest N input, and N-fertilized plants had significantly higher leaf greenness than the control at the flower initiation and mid-reproductive stages. However, N inputs had no apparent effect on yield, nitrogen use efficiency (NUE), blade total N concentration, roots (length, volume, dry biomass, and root-to-shoot ratio), or nodules (number plant−1 and biomass). For luffa, the highest N input had significantly greater total yield, fruit number, and leaf greenness at the flower initiation and mid-reproductive stages, although there was no significant difference in shoot biomass, blade total N content, or NUE among treatments. Within the range of these N rates, our results suggest that higher N inputs promoted vegetative growth of long bean, whereas reproductive growth was promoted in luffa. This study highlights differences in the sink–source relationship of N for long bean and luffa production in high tunnel, which can guide N input decisions for these two crops that are rapidly expanding in the USA.

Pitaya is a non-climacteric fruit that has white or red flesh with numerous small, black seeds. It has a high moisture content; however, water loss during handling and storage negatively affects the fresh weight, firmness and appearance of the fruit, decreasing market value. Application of compatible postharvest coatings has been shown to benefit postharvest quality of many crops. The objective of this study was to evaluate the effect of two commercial coatings on weight loss and quality of pitaya during storage. Pitaya fruit were commercially harvested and sorted for uniformity of size and freedom from defects. Fruit were briefly immersed in either a vegetable oil-based coating (VOC; Sta-Fresh® 2981) or a carnauba-based coating (CC; Endura-Fresh™ 6100) according to manufacturer’s recommendations. Fruit immersed in tap water served as a control. Fruit were fan-dried at room temperature for 20 min, then stored at 7 °C with 85% relative humidity (RH) and evaluated for selected physical quality parameters each 5 days during 20 days. After each evaluation, fruit were peeled and frozen for later analysis of soluble solids content (SSC), total titratable acidity (TTA); on day 15 fresh samples were evaluated by an untrained consumer sensory panel. CC prevented exocarp shriveling for 15 days of storage, compared to uncoated pitaya (16.3% area affected); shriveling in VOC was intermediate and not significantly different from the other treatments. Mesocarp firmness remained constant throughout 15 days of storage regardless of treatment. Fruit exocarp h* angle increased slightly by day 20, becoming slightly less red, and there were no negative treatment effects for the other quality factors measured: SSC (11.33%), TTA (0.25%), weight loss (5.5%) or sensory evaluations (appearance, flavor, texture, firmness, and juiciness). After 20 days storage, appearance for fruit from all treatments was rated unacceptable due to development of anthracnose lesions. It was concluded that both CC and VOC maintained quality of pitaya for 15 days at 7 °C and 85% RH by delaying exocarp shriveling.

Harvest of fresh market, southern highbush blueberries (SHB) is labor intensive and costly, leading to a demand for alternative harvest methods. Recent research has shown potential for mechanically harvesting blueberries with minimal bruising by using a modified over-the-row (OTR) harvester. For two harvests, SHB cultivars Optimus and Vireo were either hand-harvested (HH) or mechanically harvested (MH) by two commercial harvesters, one unmodified with standard hard-catch surfaces (HCS) or by the other modified with soft-catch surfaces (SCS). For Harvest 1, fruit from all harvest methods were hand-sorted into the following categories: blue fruit (marketable), red fruit, green fruit and culls. Samples from each cultivar and treatment were then held at 24 °C overnight, and the following day firmness and impact bruise severity were determined. Harvest 2 had identical harvest treatments; however, the fruit were sorted on a commercial packing line prior to packing in clamshells (n = 16). A subsample was held overnight as in Harvest 1 for bruise severity rating, while the remaining fruit were stored at 1 °C for 14 days (d). Although percent marketable fruit was more affected by cultivar than harvest method, determination of bruise severity revealed the benefit of harvest with SCS over HCS for both cultivars. The former had 16–26% severe bruising, compared to 27–40% for the latter; HH had 1–4%. During storage, HH fruit remained firmer than HCS and SCS, which were similar. After 14 d, firmness for “Optimus” was 239 N (HH), 157 N (HCS and SCS) and for “Vireo” it was 189 (HH), 155 N (HCS and SCS). Fruit weight loss increased during storage (1.1–4.4%), but there was no difference due to catch plate surface. SSC, TTA and Ratio were not affected by catch surface type or storage period within cultivar. Using modifications such as “soft” catch surfaces on currently available OTR harvesters reduces impact bruise damage; however, impacts incurred during commercial packing operations can negate this effect. MH for fresh market blueberries may provide an economical alternative for blueberry growers; however, with current technology, the fruit should be utilized within a week of harvest.

This chapter focuses on methods and techniques for reducing losses in postharvest quality during typical commercial handling operations. This document is HS719, Horticultural Sciences Department, UF/IFAS Extension. Published November 2006.

The importance of protecting perishable foods from loss of quality during transport has long been recognized. Increased recognition of the importance of the transport link in the food distribution cold chain in securing the safety of perishable foods has more recently become as well recognized. This updated edition reflects the dynamic changes and innovations in the handling and transportation of perishable foods. Some of these include improved insulation and air movement, microprocessors for more efficient refrigeration, expert systems to control the transport environment and conserve fuel energy, and the use of telematics to monitor and control the performance of refrigerated vehicles during transit. This edition includes descriptions and recommendations for food transported over the road and by rail in marine containers, as well as in railcars. This 214-page revision was written by J. K. Brecht, Steven A. Sargent, Patrick E. Brecht, Jorge Saenz, and Leonard Rodowick and published by the UF/IFAS Horticultural Sciences Department in cooperation with the USDA AMS Transportation Services Division. http://edis.ifas.ufl.edu/hs1328

Seed spacing directly affects crop revenue because the number of potato seeds planted determines the final plant population density. The analysis presented in this 5-page publication was extracted from a series of field trials that looked at improved potato plant arrangement in the field by adjusting seed piece spacing for Florida growing conditions. Written by Fernanda Souza Krupek, Steven A. Sargent, Peter J. Dittmar, and Lincoln Zotarelli and published by the UF/IFAS Horticultural Sciences Department, May 2018. https://edis.ifas.ufl.edu/hs1317

Florida accounts for 30% to 40% of all commercially produced fresh-market tomatoes in the United States. Almost every southern county in the state grows tomatoes. This 4-page fact sheet written by Zhengfei Guan, Feng Wu, and Steven Sargent and published by the UF/IFAS Food and Resource Economics Department presents the results of a 2015 study that examined the time it takes to harvest this important crop. http://edis.ifas.ufl.edu/fe1026

Every year farmers must harvest their crops. This process marks the end of the growing season and carries social significance in communities, but it also creates challenges for producers trying to deliver fresh, high-quality produce to market. Good postharvest practices establish appropriate cold chains that maintain the correct temperatures, humidity, and respiration rates while also ensuring the safety, sanitation, and quality of the fruits. These postharvest practices differ, depending on the size and economic situation of an operation. This 18-page fact sheet provides postharvest storage, packaging, and handling recommendations for small farm specialty crop producers. Written by Jonathan Adam Watson, Danielle Treadwell, Steven A. Sargent, Jeffrey K. Brecht, and William Pelletier, and published by the Horticultural Sciences Department, October 2015. HS1270/HS1270: Postharvest Storage, Packaging and Handling of Specialty Crops: A Guide for Florida Small Farm Producers (ufl.edu)

As a soil amendment, biochar can significantly improve soil quality and crop growth. Few studies, however, have explored biochar effects on crop quality. This study investigated the amendment effects of bamboo biochar pyrolyzed at different temperatures on plant growth and fruit quality of tomato (Solanum lycopersicum L.). Tomato ‘Micro-Tom’ plants were grown in a sand medium amended with 0, 1, and 3% of biochars produced at 300 °C, 450 °C, and 600 °C, respectively. Plant growth was monitored, and fruit harvested at the red stage was analyzed for color, texture, soluble solids content, sugars, ascorbic acid, and acidity. Results showed that biochars produced at 300 °C and amended at 3% or pyrolyzed at 450 °C and amended at 1% increased plant growth index. Contents of glucose, fructose, soluble solids, ascorbic acid, and sugar-to-acid ratios of fruits produced from the two treatments were significantly higher than the other treatments. The improved plant growth and fruit quality were related to the higher concentrations of NO3, P, Ca, and Mg in the growing media. Our results suggest that optimizing biochar use can be achieved by targeting biochar production conditions and application rate, which resulted in desirable amendment and fruit quality effects.

Harvest operations are currently the main source of mechanical injury of strawberry (Fragaria x ananassa Duch.). Experiments were designed to simulate conditions encountered during commercial handling. Individual fruits were subjected to impact or compression forces with similar energy to determine the sensitivity to mechanical injury. Bruise volume was used as the measurement of injury. Bruise severity increased as a function of impact energy for both impact types. However, dropped fruits had larger bruise volume than fruits submitted to pendulum impactor at the same energy level. Doubling the impact energy (0.040 to 0.083 J) increased bruise volume by 7 times (13 to 91 mm³). Fruits dropped from 380 mm (0.075 J) showed 71% greater bruise volume than those dropped from either 130 mm (0.025 J) or 200 mm (0.040 J). Compressed fruits showed higher bruise volume than other tests. Some cultivars are more susceptible to compression forces than others. 'Sweet Charlie' berries showed bruise volume 40% higher than the others cultivars when subjected to compression. Fruits subjected to impact showed bruise volume lower than the compressed fruits, indicating the possibility to be handled and graded in a packing line.A etapa de colheita é a principal fonte de danos físicos ao morango (Fragaria x ananassa Duch.). Experimentos foram realizados para simular condições encontradas durante manuseio. Frutos foram submetidos individualmente às forças de impacto e compressão em energias similares para determinar sensibilidade dos frutos a danos físicos. Volume da injúria física foi utilizado para mensurar a incidência do dano físico ocorrido. Severidade da lesão aumenta, com incremento da energia, tanto para força de impacto como para compressão. Todavia, frutos submetidos à queda livre demonstraram maiores volumes de danos físicos do que frutos submetidos a danos ocasionados por pendulo no mesmo nível de energia. Dobrando a energia de impacto (0,040 para 0,083 J) ocorreu aumento no volume da injúria em sete vezes (13 para 91 mm³). Frutos submetidos à queda de 380 mm (0,075 J) demonstraram volumes de danos físicos 71% superiores do que aqueles ocasionados em queda de 130 mm (0,025 J) ou 200 mm (0,040 J). Frutos em teste de compressão mostraram maiores volumes de injúrias físicas do que outros testes. Alguns cultivares são mais sensíveis à força de compressão do que outros. Frutos cultivar 'Sweet Charlie' apresentaram volume de injúria 40% superiores do que outros quando submetidos à força de compressão. Morangos submetidos à força de impacto demonstraram volume de injúria inferior do que aqueles comprimidos, indicando a possibilidade dos morangos serem classificados e manuseados em uma linha de beneficiamento.

What is a rapid postharvest decay? Water-soaked lesions begin within 12 to 18 hours after harvest and continue to develop, producing large amounts of fluids. The decay spreads within cartons of tomatoes, producing wet patches in the bottom and sides of the container, a condition called “wet-boxes.” Affected fruit are out-of-grade either prior to shipment or upon arrival at the receiver. This revised 5-page fact sheet was written by J. A. Bartz, S. A. Sargent, and D. J. Huber, and published by the UF Department of Horticultural Sciences, December 2014. (Photo: S. R. Bartz)

If picked at the proper mature-green stage and handled properly, tomatoes will ripen to excellent edible quality. Proper postharvest handling of Florida tomatoes is critical to ensure the continued competitiveness of Florida growers.This publication focuses on round and roma (plum) tomatoes since these types are handled similarly under commercial conditions. Originally published August 1989. Revised November 2005, by Steven A. Sargent, Jeffrey K. Brecht, and Teresa Olczyk. This update December 2014 with Qingren Wang.