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Two of the major postharvest diseases impacting grapefruit shelf life and marketability in the state of Florida (USA) are stem-end rot (SER) caused by Lasiodiplodia theobromae and green mold (GM) caused by Penicillium digitatum. Here, we investigated the in vitro and in vivo efficacy of vapors of thymol, a natural compound found in the essential oil of various plants and the primary constituent of thyme (Thymus vulgaris) oil, as a potential solution for the management of GM and SER. Thymol vapors at concentrations lower than 10 mg L−1 significantly inhibited the mycelial growth of both pathogens, causing severe ultrastructural damage to P. digitatum conidia. In in vivo trials, the incidence and lesion area of GM and SER on inoculated grapefruit were significantly reduced after a 5 d exposure to 50 mg L−1 thymol vapors. In addition, the in vitro and in vivo sporulation of P. digitatum was suppressed by thymol. When applied in its vapor phase, thymol had no negative effect on the fruit, neither introducing perceivable off-flavor nor causing additional weight loss. Our findings support the pursuit of further studies on the use of thymol, recognized as safe for human health and the environment, as a promising strategy for grapefruit postharvest disease management. [ABSTRACT FROM AUTHOR]

Along with orange and mandarin, grapefruit production in Florida has declined sharply due to Huanglongbing (HLB), or citrus greening disease, caused by Candidatus Liberibacter asiaticus (CLas). HLB affects the volatile profiles of juice and peel oil in oranges, but there is limited information on grapefruit. In this research, 'Ray Ruby' grapefruit were harvested in 2020 and 2021 from healthy (HLB−) and HLB-affected (HLB+) trees. Peel oil was extracted by hydrodistillation, and the volatiles were analyzed by direct injection of the oil samples into gas chromatography–mass spectrometry (GC-MS). Volatiles in the juice were analyzed by headspace (HS)-solid-phase microextraction (SPME) coupled with GC-MS. HLB significantly altered the volatile profiles of peel oil and juice in 'Ray Ruby' grapefruit. Juice samples of HLB+ fruits had lower decanal, nonanal, and octanal, important citrus juice flavor compounds. HLB+ samples also showed reduced content of nonterpene compounds, other aliphatic and terpene aldehydes, and terpene ketones. Ethanol, acetaldehyde, ethyl acetate, and ethyl butanoate were increased in HLB+ juice samples, indicating an HLB-induced stress response. The most abundant compounds D-limonene and β-caryophyllene, as well as other sesquiterpenes, were increased in HLB+ juice and peel oil samples. On the other hand, the oxidative/dehydrogenated terpenes were increased by HLB in peel oil but decreased in the juice sample. Nootkatone, the key grapefruit volatile was consistently reduced by HLB in both peel oil and juice samples. The impact of HLB on nootkatone deteriorated the quality of both juice and peel oil in grapefruits. [ABSTRACT FROM AUTHOR]

Florida orange trees have been affected by huanglongbing (HLB) for more than a decade. To alleviate disease-caused tree decline, maintain fruit productivity, and reduce disease transmission, enhanced foliar spray programs combining vector control and nutritional supplementation have been applied to healthy and diseased trees. The aim of this research was to discover if the various foliar sprays affect fruit peel oil chemical components. In this study, "Valencia" orange trees, with or without HLB (HLB±), were treated with the grower standard program (control, C) or one of four proprietary enhanced foliar spray programs (N1, N2, N3, and N4) over 16 months. Compared with HLB−, HLB+ samples had lower concentrations of typical peel oil components, including valencene, octanal, and decanal, and were abundant in oxidative/dehydrogenated terpenes, such as carvone and limonene oxide. However, limonene, the dominant component, was not affected by any treatment. Control and three out of four enhanced foliar spray programs, N2, N3, and N4, had very little influence on the chemical profiles of both HLB− and HLB+ samples, while N1 treatment greatly altered the chemical profile of HLB+ samples, resulting in peel oil similar to that of HLB− samples. [ABSTRACT FROM AUTHOR]

The strawberry breeding program of the University of Florida develops varieties that are highly adapted to west-central Florida, where approximately 8,800 acres of strawberries were grown during the 2009–10 season. In order to gain insight into breeding progress over time, two advanced selections and ten released cultivars, from Florida Belle (1975) to Florida Radiance (2008), were compared for various fruit quality traits. Cultivars and selections were arranged in a randomized complete block design at each of two locations (Balm, FL and Dover, FL). Fruit size varied dramatically with a minimum average weight of 16.2 g for ‘Dover’ (1979) and a maximum of 30.8 g for ‘Elyana’ (2008). Regression of average fruit weight on year of release showed an average gain in fruit size of 0.26 g/yr (R2 = 0.44). Improvements in fruit uniformity were also apparent, but gains for internal flesh color were not sustained. There was wide seasonal variability in sugars (sucrose, glucose, fructose, Brix) and acids (citric, malic, and titratable acidity); March tended to produce fruit with lower sugars. Sugars were highest in February while acids were highest in January. Also, correlations were found between sugars and volatiles having fruity and strawberry characters. Comparison of chemical data with sensory data from related studies indicates that instrumental measures, particularly for SSC/TA, could aid in breeding for improved flavor. [ABSTRACT FROM AUTHOR]

• 21 papaya accessions were evaluated, including large-fruited and solo types. • Yield, fruit size, soluble solids, and titratable acidity varied among accessions. • 124 volatiles were detected, and 25 had odor activity by GC-O. • A few papaya accessions have potential for commercial production in Florida. Papaya (Carica papaya L.) is a globally popular tropical fruit that can either be used in an unripe, "mature green" state in savory dishes, or consumed when ripe and sweet. In recent years, commercial papaya growers in southern Florida have favored large-fruited accessions often destined for the mature green market. Increased cultivation of papayas for the dessert fruit market, especially varieties with superior fruit quality may facilitate growth of the industry. Therefore, a study was designed to identify varieties that perform well in southern Florida, as well as accessions possessing useful characteristics for future breeding work. A total of 21 papaya accessions were assessed for yield components, plant height, and ripe fruit quality traits with an emphasis on aroma. In general, small fruited solo-type papayas were among the tallest accessions at first harvest reaching up to 244 cm tall for 'Kapoho #1' and with first fruit insertion heights up to 152 cm for 'Kapoho #2'. N08–75, 'Sunrise #2', and 'Sunset' had higher average fruit numbers (43, 45, and 37 fruit per plant, respectively) than some of the larger fruited accessions like Saipan Red #1 (7 fruit per plant) throughout a six-month harvest period. The accessions with the highest fruit weights ranged from 1.48 to 2.13 kg for Brash Panama, HAES 7836, N07–24, Saipan Red #1, and Saipan Red #2. There were significant differences among the accessions for fruit quality traits including pH (4.55–5.13), titratable acidity (0.10–0.23%), and total soluble solids (8.9–14.5%). Quantification of 112 putatively identified and 12 unknown volatile compounds revealed terpenes as the most abundant components in 18 accessions, with linalool typically at the highest concentration. Gas chromatography-olfactometry (GC-O) revealed 26 volatiles that may contribute to aroma. Several of these compounds including butanoic acid, methyl butanoate, octanoic acid, and (E)-citral varied greatly in abundance among accessions. The variability observed for important fruit quality and agronomic traits suggests potential for improvement through plant breeding, as well as expanded cultivation of currently available varieties for the dessert fruit market in southern Florida. [ABSTRACT FROM AUTHOR]

Fruit quality is of increasing importance for consumers but is a complex trait for growers, as it is affected by environment, genotype, and crop management interactions. Decision support tools, such as computer models that simulate crop growth and development can help optimize production but require further improvement to simulate quality aspects. The goal of this study was to apply the newly developed CROPGRO-Strawberry model in the Decision Support System for Agrotechnology Transfer (DSSAT) model framework and develop a module for the dynamic prediction of quality traits for strawberry. Experimental data from Florida with quality measurements from multiple harvests were correlated with indices based on preharvest weather conditions (temperature, radiation, rainfall) and simulated model parameters (evapotranspiration) during fruit development. Two quality relationships based on linear equations were identified and integrated into the model to simulate strawberry fruit soluble solids content (r ² 5 0.89, d 5 0.97) and titratable acidity (r ² 5 0.55, d 5 0.85) based on preharvest temperature. A strategic analysis with historical weather data for a subtropical growing region over a 10-year period showed the importance of seasonal climate variability for simulated strawberry yield and fruit quality across different harvest months. The improved CROPGRO-Strawberry model is the first process-based crop model to predict selected quality traits across multiple harvests throughout the season and can be extended to other crop models for which quality traits are important [ABSTRACT FROM AUTHOR]

• A large variation in total oil content was found among14 avocado genotypes. • Oleate, palmitate and linoleate were the major fatty acid components in all genotypes. • Acetaldehyde, C-6 aldehydes and mono/sesquiterpenes were the major VOCs. • '35707' and 'PA-6206' were rich in total oil content and unsaturated fatty acids. Worldwide avocado consumption is growing due to potential health benefits. Most research has been focused on 'Hass', which does not perform well in Florida. Fatty acids and volatile organic compounds (VOCs) were evaluated in 14 avocado genotypes grown in East-Central Florida conditions and compared to 'Hass'. Two saturated and five unsaturated fatty acids were detected. Total oil content (TOC) was 11–25%, with 58.2–71.5% unsaturated fatty acids (UFA). 'FL Hass' contained 20% TOC, near the average for genotypes tested, but with a low UFA of 61.9%. 'PA-6206' (a 'Hass' x 'Bacon' seedling) and '35707' (a 'Catalina' seedling) had higher TOC and UFA than other genotypes, while the mostly West Indian types such as 'Simmonds', 'Day', 'Pflume' and 'Miguel' had low TOC. Detected VOCs were acetaldehyde, hexanal, (E)-2-hexenal, limonene, α-cubebene, α-copaene, and β -caryophyllene. Most genotypes contained most of the VOCs. 'Monroe' lacked C6 aldehydes, and 'Pflume', 'Bernecker-43', 'Lula' and '35707' lacked some or all sesquiterpenes. [ABSTRACT FROM AUTHOR]

The article informs about different forms of Fragaria chiloensis cultivated by native individuals in South America also known as White-fruited strawberries. Topics include Newer cultivars with fruit sizes similar to that of red strawberries that have recently emerged as high-value products in Asia; and existing pineberry cultivars are not suitable for commercial production in Florida.

The article offers information on the strawberry cultivar Sensation "Florida127" grown in Florida. Topics discussed include a description of the cultivar, the plant's origin and pedigree, and the advantage of its moderate plant size and long pedicels. Also mentioned are the marketable yield and average fruit weight of the variety.

The University of Florida strawberry (Fragaria xananassa Duch. ex Rosier) breeding program has maintained a continuous breeding effort since 1968 to develop cultivars that are highly adapted to winter production in west-central Florida. To gain insight into breeding progress over time, two advanced selections (UF1 and UF2) and 10 released cultivars, from Florida Belle (1975) to Florida Radiance (2008), were compared for various fruit quality traits in a two-location field study during the 2009-2010 season. Fruit size varied dramatically from 30.8 g for 'Elyana' to 16.2 g for 'Dover' at Balm, FL, and from 28.3 g for UF2 to 16.6 g for 'Dover' at Dover, FL. A linear regression of fruit size on year of release revealed an average gain of 2.6 g per year since 1975 for the cultivars and selections tested (R² = 0.44). A similar analysis revealed a reduction over time in the proportion of cull fruit (R² = 0.30). Gains were apparent for the redness of the internal flesh, from a colorimeter a* value of 16.1 for 'Florida Belle' (1975) to 34.7 for 'Carmine' (2002) but were not sustained for later releases and selections. Although there were significant differences among genotypes for all chemical traits affecting flavor, there were no discernable patterns over time. There were wide month-to-month variations in individual sugars and organic acids, except for citric acid, which was stable across months and locations. The ratio of soluble solids content to titratable acidity ranged widely among genotypes, from a high of 15.7 for 'Florida Belle' in February at Dover, FL, to a low of 6.4 for 'Winter Dawn' in January at Balm, FL. The observed variability and trends in fruit quality traits will help guide future genetic studies and inform decisions about future breeding priorities and selection procedures. [ABSTRACT FROM AUTHOR]

The article information on a primary strawberry cultivar Winterstar. The cultivar is currently in experimental plots at the University of Florida Gulf Coast Research and Education Center and on trials on several commercial farms in Florida. It originated from a 2005 cross between Florida Radiance and Earlibrite. Information on its pedigree, field performance and commercialization is also provided.

The article deals with the origin, description, performance and availability of a strawberry cultivar called Florida Radiance strawberry. The fruit is produced from a cross between 2001 Winter Dawn and FL 99-35 varieties. It notes that the cultivar has a more open plant habit, making it easy to harvest. The color of the external part of the fruit is a glossy bright to dark red while the inside is warm red in color.

The article focuses on Florida Elyana, the first strawberry cultivar breed in Florida designed for tunnel and greenhouse production. It notes the susceptibility of the fruit to surface cracking due to exposure to free moisture and because of this, the fruit is not recommended for open-field culture. The external fruit color is bright red while carmine pink is the internal fruit color. Also cited is the resistance of the fruit to Botrytis fruit rot and anthracnose fruit rot, as well as to wilts.

More than 90% of oranges in Florida are processed, and since Huanglongbing (HLB) disease has been rumored to affect fruit flavor, chemical and physical analyses were conducted on fruit and juice from healthy (Las -) and diseased (Las +) trees on three juice processing varieties over two seasons, and in some cases several harvests. Fruit, both asymptomatic and symptomatic for the disease, were used, and fresh squeezed and processed/pasteurized juices were evaluated. Fruit and juice characteristics measured included color, size, solids, acids, sugars, aroma volatiles, ascorbic acid, secondary metabolites, pectin, pectin-demethylating enzymes, and juice cloud. Results showed that asymptomatic fruit from symptomatic trees were similar to healthy fruit for many of the quality factors measured, but that juice from asymptomatic and especially symptomatic fruits were often higher in the bitter compounds limonin and nomilin. However, values were generally below reported taste threshold levels, and only symptomatic fruit seemed likely to cause flavor problems. There was variation due to harvest date, which was often greater than that due to disease. It is likely that the detrimental flavor attributes of symptomatic fruit (which often drop off the tree) will be largely diluted in commercial juice blends that include juice from fruit of several varieties, locations, and seasons.