Fresh Fruit Market Research Articles

2018–2019 Florida Citrus Production Guide: Postbloom Fruit Drop

Postbloom fruit drop (PFD) must be controlled on processing and fresh market fruit. PFD, caused by the fungus Colletotrichum acutatum, affects all species and cultivars of citrus, but severity on a given cultivar varies according to the time of bloom in relation to rainfall. Navel and Valencia oranges have experienced the most severe damage in Florida since they tend to have extended or multiple blooms. This 3-page fact sheet is part of the 2018–2019 Florida Citrus Production Guide. Written by Natalia A. Peres and Megan M. Dewdney, and published by the Plant Pathology Department, May 2018. PP-45/CG007: 2022–2023 Florida Citrus Production Guide: Postbloom Fruit Drop (ufl.edu)

2018–2019 Florida Citrus Production Guide: Brown Rot of Fruit

Management of brown rot, caused by Phytophthora nicotianae or P. palmivora, is needed on both processing and fresh market fruit. While the disease affects all citrus types, it is usually most severe on Hamlin, Navel, and other early maturing sweet orange cultivars. This 2-page fact sheet is part of the 2018–2019 Florida Citrus Production Guide. Written by Megan M. Dewdney, Evan G. Johnson, and James H. Graham, and published by the Plant Pathology Department, May 2018. PP-148/CG022: 2022–2023 Florida Citrus Production Guide: Brown Rot of Fruit (ufl.edu)

First Report of Phyllosticta citricarpa Causing Citrus Black Spot on Citrus sinensis and C. reticulata in India

Citrus is an economically important fruit crop in India. In December 2016, citrus black spot (CBS)-like symptoms were observed on Nagpur mandarin (Citrus reticulata), ‘Mosambi’ sweet orange, and Cutter Valencia (C. sinensis) trees in two orchards situated at Mohpa and Kachimet localities of Nagpur district, Maharashtra state (21.14 to 21.30°N, 78.82 to 79.02°E). Later symptoms were also noticed on Nagpur mandarin and Mosambi fruits in the fresh fruit market of Nagpur (also known as “Orange City”). Fruit symptoms included hard spot, red-brown spot, freckle spot, and virulent spot. To isolate the causal agent, fruit lesions were surface disinfested with 1% NaOCl and plated on potato dextrose agar (PDA) and oatmeal agar (OA). Fifteen single-spore cultures resembling those of the genus Phyllosticta were obtained. On PDA, the colonies had irregular margins, with numerous pycnidia, lined by a translucent zone of colorless submerged mycelium. On OA, a distinct yellow pigment was produced that diffused into the medium around the colony. Conidia (9.6 to 10.3 × 5.9 to 9.0 μm; average, 9.9 × 7.3 μm; n = 30) were hyaline, aseptate, ovoid with a flattened base surrounded by a hyaline matrix (0.8 to 1.1 μm; average, 0.9 μm; n = 30) and a hyaline appendage (6.6 to 13.6 μm; average, 8.8 μm; n = 30) on the rounded apex, corresponding to published descriptions of P. citricarpa (sexual morph Guignardia citricarpa) (Baayen et al. 2002). Leptodothiorella spermatial state formed in pure culture, and spermatia (4.8 to 7.9 × 0.8 to 1.3 μm; average, 7.0 × 1.0 μm; n = 30) were hyaline, dumbbell shaped to cylindrical, and both ends bluntly rounded. No sexual structures were observed. DNA was extracted from six representative isolates (CB1 to CB6) using a Qiagen DNeasy Plant Mini Kit. The nuclear ribosomal internal transcribed spacer (ITS) region (GenBank accession nos. MF000337 to MF000341 and MF062501) and the translation elongation factor 1-alpha gene (tef1) (MF000342 to MF000347) were amplified and sequenced using universal primer pairs ITS5/ITS4 and EF1-728F/EF2, respectively. These isolates shared 99 to 100% nucleotide sequence similarity (for both ITS and tef1) among themselves and had 99 to 100% homology with P. citricarpa ITS sequences from the United States (GenBank no. KC311457) and South Africa (KF709953) and with the P. citricarpa tef1 sequence of an Australian isolate (GenBank no. JF343602). The P. citricarpa-specific primers GCN and GCMR (Peres et al. 2007) produced a 300-bp band from the DNA extracts of fruit lesions and pure cultures but not from healthy citrus tissue DNA. To confirm pathogenicity, two isolates (CB1 and CB4) were inoculated into Mosambi sweet orange (six fruits for each isolate), as described by Rodrigues et al. (2013). After 30 days, all the inoculation sites showed early hard spot-like CBS symptoms. Control fruits remained symptomless. P. citricarpa was consistently reisolated from the fruit lesions and identified by morphology and ITS sequencing. Earlier, P. citricarpa was noted on Citrus medica leaves in Chennai, India (Kumaran et al. 2008), but there was no proof of identification and characterization of the species. To our knowledge, this is the first confirmed report of P. citricarpa causing CBS in two economically important Citrus species, C. sinensis and C. reticulata, in India. The disease is of great importance to the Indian citrus industry because it inflicts serious fruit blemishes and can cause severe yield reduction under heavy disease pressure.

The role of social enterprise in food insecurity among asylum seekers.

People seeking asylum in high-income countries are vulnerable to food insecurity due to limited opportunities for social and economic participation. Given this vulnerability, nongovernment organisations are attempting to improve food security outcomes through targeted programmes. This study explored the role of a subsidised mobile fresh fruit and vegetable market (the Food Justice Truck-FJT) on the experience of food insecurity for people seeking asylum living in Melbourne, Australia. This research uses a mixed methods approach, employing surveys and semistructured interviews to explore the lived experiences of asylum seekers using the FJT, including their experiences of food insecurity. Half of the asylum seekers interviewed in this study were found to be experiencing food insecurity. Participants in this study sourced food from multiple locations, with the FJT providing a supplemental, but highly valued source of fresh produce. The FJT was identified as positive social setting for some participants included in this research. This research has identified the ability of programmes such as the FJT to act as positive social settings.

Characteristics of the fruits of two uvaia populations grown in Salesópolis, SP, Brazil

Abstract Uvaia (Eugenia pyriformis Cambess) is a fruit tree native to the Atlantic Forest and that features peculiar aroma and flavor. Although this fruit is highly popular locally, its commercial farming is virtually nonexistent. In addition, limited studies on this fruit have been conducted. Therefore, the present study aimed to investigate the physical, chemical, and functional characteristics of two uvaia fruit populations grown in Salesópolis, SP, Brazil, in order to determine their potential for being consumed both in natura and processed. Uvaia fruits were evaluated as for skin color, whole fruit weight, longitudinal and transversal diameters, seed percentage, pulp yield, pulp firmness, pH, total soluble solids (TSS), total titratable acidity (TTA), TSS/TTA ratio, total soluble sugars, soluble and total pectins, total carotenoids, yellow flavonoids, total phenolic compounds, ascorbic acid, and in vitro antioxidant capacity (DPPH and ORAC assays). The total mineral content was also determined. Comparison among the two populations revealed that uvaia fruits showed significantly different firmness values, large fruits showing suitable characteristics for the fresh fruit market. However, small fruits were sweeter and richer in antioxidants, allowing the consumption of both natural and processed fruits. Thus, this native fruit denotes an important source of nutrients and bioactive compounds, especially iron.

Fruit quality and production of yellow and sweet Passion fruits in northern state of São Paulo

Abstract Yield and quality of yellow and sweet passion fruits produced in northern state of São Paulo, Brazil were evaluated, including FB200 Yellow Master, Isla Redondo Amarelo, BRS Rubi do Cerrado, BRS Sol do Cerrado and BRS Gigante Amerelo cultivars, GP09-02, GP09-03, H09- 09, H09-14, HFOP-08 and HFOP-09 intraspecific hybrids, and two selections of sweet passion fruits, BGP DG and BGP DP. Experimental design was comprised of randomized blocks with 13 treatments, five replicates and three plants per plot. BGP DG was the sweet passion fruit selected for fresh fruit market as a result of its higher yield (52.7 t ha-1) and fruit size and mass (243 g). Among yellow passion fruits, GP09-02 stood out because it showed the highest number of fruits per plant after two years of cultivation, even though GP09-02, H09-09, BRS Sol do Cerrado, Isla Redondo Amarelo and FB200 had also presented higher juice content, on average 32.3%, and equivalent accumulated fruit yield. All fruits had high soluble solids contents, with higher concentration for sweet passion fruits (20.0 °Brix) than yellow passion fruits (average of 14.28 °Brix). These cultivars, hybrids and selections have potential for cultivation in northern state of São Paulo and in regions with similar edaphoclimatic conditions.

Utilisation Des Caractères Biochimiques, Agronomiques Et Morphologiques Pour L’évaluation De La Diversité Génétique Des Variants D’orangers Dans La Région Du Gharb, Maroc

20 clones of orange trees, identified at the level of the collection of nucellar citrus varieties, have been the subject of several tests of behavior at the level of different citrus fruit sites in Morocco. Indeed, the present work aims to evaluate these variants on a clay soil at the Gharb region (INRA/Kenitra). The variants grafted on Citrange troyer were divided into three groups. Each group contains variants, genetically similar, from seedlings of the same parent variety. Clonal selection is based on the synthesis of the results of the study of the variability of the criteria of fruit quality and production. The average yield varies from 44.25 kg / tree to 217.30 kg / tree. While the average weight of a fruit varies from 95 g to 360 g. The results showed a predominance of juicy and medium-sized fruits with an equatorial diameter greater than 56 mm, acceptable for the fresh fruit market or the juice industry. The maturity coefficient study of the variants within each group, or between the three groups, showed that the harvest period extends over four months, from December to March. The final selection was focused on six productive and good quality variants. These promising variants have been described according to UPOV, and then presented for registration in the official catalog.

Influence of ethylene and ethephon treatments on the peel color and carotenoids of Gannan Newhall navel orange during postharvest storage

Gannan Newhall navel orange was treated by ethylene and ethephon separately. The color of Gannan Newhall navel orange peel was influenced significantly by ethylene and ethephon treatments. During postharvest storage, the ratio of chlorophylls and carotenoids in the peel reduced which led the peel color changing from green to yellow when treated by ethephon and to orange-red when treated by ethylene. Results of the CIELAB chroma system evaluation were consistent with sensory evaluation. Ethylene and ethephon treatments decreased β-carotene and lutein contents and increased β-cryptoxanthin content largely (converted β-carotene to β-cryptoxanthin) in citrus peel. Besides, ethylene and ethephon treatments could convert yellow violaxanthin to neoxanthin or zeaxanthin. In ethylene treatment, its peel color changing to orange-red due to β-cryptoxanthin converted to β-citraurin, which made Gannan Newhall navel orange exhibited the welcomed color (orange-red). It was desirable for citrus postharvest process. Practical applications The color of citrus fruit has become an important factor affecting fresh fruit price and market competitiveness. Studies have shown that citrus peel color is mainly affected by the content and proportion of chlorophylls and carotenoids. This study is aimed to illustrate the transformation of carotenoids and the mechanism of regulation of ethylene on the navel orange peel changing from green to orange-red. The results of this research could provide scientific supports for citrus's atmosphere controlled storage, which could produce added value.

A Precision Pruning Strategy for Improving Efficiency of Vibratory Mechanical Harvesting of Apples

Abstract. The state of Washington is the biggest fresh market apple ( Borkh.) producer in the U.S., and the state’s annual apple production has exceeded 60% of the national production. Due to the extensive labor requirements for harvesting fresh market apples, there is burgeoning demand for mechanical harvest solutions. Our transdisciplinary studies on mechanical harvest systems for apples have shown that fruit removal efficiency (FRE) with a vibratory system can be improved with precision canopy management. In this study, we evaluated the effect of precision pruning strategies on FRE in two groups (106 and 107, respectively) of randomly selected horizontal branches of ‘Jazz/M.9’ apple trees in a commercial orchard. Fruiting lateral branches were pruned to either shorter than 15 cm (guideline 1, G1) or 23 cm (guideline 2, G2). Harvest tests were conducted using a shake-and-catch harvester prototype developed by Washington State University with a fixed vibrating frequency of 20 Hz and shaking duration of 5 s. FRE for branches treated with G1 was significantly higher (91%) than FRE for branches treated with G2 (81%). We recorded a negative relationship between FRE and lateral shoot length. FRE was up to 98% when shoots were shorter than 5 cm, and FRE was only 56% for shoots of 25 cm or longer. We developed a shoot diameter-to-length index (S-index) to better understand the effect of shoot size on FRE. FRE was as high as 98% when the S-index was greater than 0.15. In addition, mechanically harvested fruit quality was assessed by categorizing the fruit into Extra Fancy, Fancy, and Downgrade fresh market classes based on USDA standards; however, no significant difference was found between the two treated groups. These results suggest that pruning lateral fruiting branches to less than 15 cm or to an S-index greater than 0.03 is required to achieve FRE of 85% with no negative impacts on fruit quality. Keywords: Canopy management, Fresh market fruit, Fruit removal efficiency, Mechanical harvest, Shoot pruning severity.

‘JAFFA’ SWEET ORANGE PLANTS GRAFTED ONTO FIVE ROOTSTOCKS

ABSTRACT Low genetic diversity of citrus scion and rootstock cultivars makes the crop more vulnerable to diseases and pests. The objective of this study was to evaluate the performance of ‘Jaffa’ sweet orange grafted onto five rootstocks over six harvests in subtropical conditions in the north of Paraná state, Brazil. The experiment used a randomized block design, with six replications and two trees per plot, spaced at 7.0 m x 4.0 m. The rootstocks were: ‘Rangpur’ lime, ‘Cleopatra’ and ‘Sunki’ mandarins, ‘Fepagro C-13’ citrange, and ‘Swingle’ citrumelo. The variables evaluated were vigor, yield, and yield efficiency of the trees as well as the physical and chemical characteristics of the fruits. Data were subjected to analysis of variance, complemented by Scott-Knott test at 5% probability. The smallest tree canopy for ‘Jaffa’ sweet orange plants was induced by the ‘Rangpur’ lime rootstock. The trees had the same cumulative yield performance over six seasons for all rootstocks. The best yield efficiency for ‘Jaffa’ sweet orange trees was provided by ‘Fepagro C-13’ citrange rootstock. With regard to fruit quality, no differences were observed among the rootstocks and the ‘Jaffa’ sweet orange fruits met the standards required by the fresh fruit market and the fruit processing industry.

Preliminary Valuation of “Y” and “V”-Trellised Canopies for Mechanical Harvesting of Plums, Sweet Cherries and Sour Cherries for the Fresh Market

Abstract Plums, sweet cherry, and sour cherry trees were spaced 4.5 m × 1.5 m to be trained to “Y” and “V”-trellising systems for mechanical harvesting, with a canopy contact harvester, attending to obtain fruits meeting the requirements of the fresh fruit market. The applied trellising systems were compared with the standard central leader system at the same spacing. The most of trellised trees grew less vigorously than the standard trees, and after 3 years of training, the trees were suitable for mechanical harvesting with the harvester designed at the Research Institute of Horticulture in Skierniewice. The trellised trees were able to set as many fruitlets as those grown in the form of central leader and gave a comparable yield, but differences between cultivars were significant. Light interception in the third year after planting was lower for trees of sour cherry and plum growing in the “Y”-20° and “V” in comparison to the trees with central leader. Illumination of trellised canopies at the level of 0.7 and 1.5 m was the most favorable in “V” system when compared to control and “Y” training systems. Cost of construction for the trellising systems of stone fruits calculated per 1 ha was two times higher when compared with the standard system.

Genotyping by sequencing reveals the interspecific C. maxima / C. reticulata admixture along the genomes of modern citrus varieties of mandarins, tangors, tangelos, orangelos and grapefruits.

The mandarin horticultural group is an important component of world citrus production for the fresh fruit market. This group formerly classified as C. reticulata is highly polymorphic and recent molecular studies have suggested that numerous cultivated mandarins were introgressed by C. maxima (the pummelos). C. maxima and C. reticulata are also the ancestors of sweet and sour oranges, grapefruit, and therefore of all the “small citrus” modern varieties (mandarins, tangors, tangelos) derived from sexual hybridization between these horticultural groups. Recently, NGS technologies have greatly modified how plant evolution and genomic structure are analyzed, moving from phylogenetics to phylogenomics. The objective of this work was to develop a workflow for phylogenomic inference from Genotyping By Sequencing (GBS) data and to analyze the interspecific admixture along the nine citrus chromosomes for horticultural groups and recent varieties resulting from the combination of the C. reticulata and C. maxima gene pools. A GBS library was established from 55 citrus varieties, using the ApekI restriction enzyme and selective PCR to improve the read depth. Diagnostic polymorphisms (DPs) of C. reticulata/C. maxima differentiation were identified and used to decipher the phylogenomic structure of the 55 varieties. The GBS approach was powerful and revealed 30,289 SNPs and 8,794 Indels with 12.6% of missing data. 11,133 DPs were selected covering the nine chromosomes with a higher density in genic regions. GBS combined with the detection of DPs was powerful for deciphering the “phylogenomic karyotypes” of cultivars derived from admixture of the two ancestral species after a limited number of interspecific recombinations. All the mandarins, mandarin hybrids, tangelos and tangors analyzed displayed introgression of C. maxima in different parts of the genome. C. reticulata/C. maxima admixture should be a major component of the high phenotypic variability of this germplasm opening up the way for association studies based on phylogenomics.

Determination of fruit maturity and its prediction model based on the pericarp index of absorbance difference (IAD) for peaches.

Harvest maturity is closely related to peach fruit quality and has a very important effect on the fresh fruit market. Unfortunately, at present, it is difficult to determine the maturity level of peach fruits by artificial methods. The objectives of this study were to develop quadratic polynomial regression models using near-infrared spectroscopy that could determine the peel color difference, fruit firmness, soluble solids content (SSC), soluble sugar, organic acid components, and their relationships with the absorbance of chlorophyll (index of absorbance difference, IAD) in late maturing ‘Xiahui 8’ peach and ‘Xiaguang’ nectarine fruits. The analysis was based on data for fruits at veraison, fruits at harvesting maturity, and all fruits. The results showed that firmness has the highest correlation coefficient with IAD. Prediction models for fruit maturity were established between firmness and the IAD of the two cultivars using the quadratic polynomial regression method. Further variance analysis on the one degree term and quadratic term of each equation showed that every partial regression coefficient reached a significant or extremely significant level. No significant difference was observed between estimated and observed values after regression prediction. The regression equations seem to fit well. Other peach and nectarine varieties were used to test the feasibility of maturity prediction by this method, and it was found that maturity was successfully predicted in all the samples. The result indicated that the IAD can be used as an index to predict peach fruit maturity.

GABA Pathway Rate-Limit Citrate Degradation in Postharvest Citrus Fruit Evidence from HB Pumelo (Citrus grandis) × Fairchild (Citrus reticulata) Hybrid Population.

Organic acids are a major index of fresh fruit marketing properties. However, the genetic effects on the organic acid level in postharvest citrus fruit still remain unknown. Here, we used the fruits of about 40 lines in a hybrid population (high-acid "HB Pumelo" × low-acid "Fairchild") to analyze the organic acid metabolism of postharvest citrus fruit. A transgressive content of titratable acid (TA) was observed, which was attributed to citrate accumulation. High- and low-acid fruits (No. 130, 168 and No. 080, 181, respectively) were chosen for further study. Gene expression analysis on citrate metabolism showed that the high accumulation of citrate could be attributed to the low activity of γ-aminobutyric acid (GABA) shunt, and was partially due to the block of tricarboxylic acid (TCA) cycle by low mitochondrial aconitase (m-ACO) expression. TA level was significantly negatively correlated with weight loss in fruits during postharvest storage, implying a close relationship between organic acid and water metabolism.

Infection and symptom development by citrus scab pathogen Elsinoë fawcettii on leaves of satsuma mandarin

Elsinoe fawcettii, a fungal pathogen causing scab disease in citrus, is one of the destructive diseases having an adverse role in the fresh fruit market. We observed the infection behaviour of E. fawcettii on young leaves of satsuma mandarin daily and described the time course of symptom development with a focus on morphological changes during disease progress. The E. fawcettii isolate 16–1, belonging to Florida Broad Host Range (FBHR), was infectious and generated typical symptoms on adaxial as well as abaxial surfaces of the leaf. Of the conidia inoculated and adhered, only a few were able to germinate and create typical symptoms. Conidia extended their germ tubes from 1 day post-inoculation where a few possessed globose appressorium-like structures (APL) at their tip. The APL were found on both surfaces while symptoms could be produced without them. Dark regions were induced 1–2 days post-inoculation (dpi) under fluorescent microscopic observation. Cuticle and mesophyll cells including epidermis in the infected dark region were degraded, resulting in cellular necrosis. The adjacent cells of the necrotic region were enlarged and gradually covered leaving a grooved shaped necrotic center and appeared as a first visible symptom 3 dpi. Hyphae were extended through the necrotic epidermis and colonized intra- and inter-cellularly in mesophyll tissue. Also lamellated cell-wall was observed as a boundary between infected and non-infected regions in the lesion after typical symptoms were formed. The lamellation in the cell simultaneously occurred forming a compaction of host cells and a semi-circular arc of lammellated cells was formed on the boundary of the infected and non-infected regions of the lesion.

Industrial tomato lines: morphological properties and productivity

The tomato is the second most produced vegetable in the world, with significant participation in the human diet. In addition, the production of tomatoes generates jobs and family income. The availability of improved cultivars that provide greater profitability to the producer and satisfactorily meets the needs of the fresh fruit market and the processing industry becomes imperative due to its importance. Therefore, this study aimed to characterize and select industrial tomato lines in regard to fruit yield, number of leaf branches, and number of flower racemes (NFR). The experiment was conducted in 2014 in the experimental area of the Federal University of Goiás (Universidade Federal de Goiás). The design was a randomized block design with four replicates and 25 genotypes. The number of leaf branches (NB), NFR, and fruit productivity were evaluated. The results were analyzed using analysis of variance and the means compared by the Tukey test. A difference was observed (P ≤ 0.01) for all traits analyzed. The NB and NFR were related, where more branches promoted an increase in NFR and thus the productivity increases. In addition, a greater number of fruits implied in smaller fruit size, and consequently lower fruit mass. The lowest number of fruit per plant caused increased fruit size and mass. The lines CVR 1, CVR 3, CVR 4, CVR 5, CVR 21, and CVR 22 were suitable for genetic enhancement of tomato and provided the greatest productivity.

Phenological cycle and physicochemical characteristics of avocado cultivars in subtropical conditions

Avocado has a great potential as a commercial crop in southern Brazil, for its high productivity, rusticity, and multiple uses. Its high oil content can be explored for biodiesel production with advantages over other crops. This study comprised six avocado cultivars-Geada, Fortuna, Fuerte, Margarida, Primavera and Quintal-belonging to the Agronomic Institute of Parana (IAPAR) collection, from Londrina, Brazil (23° 23′ S, 50° 11′ W). Analysis of fruit growth (length and diameter) allowed the classification of the cultivars into groups showing early, midseason, and late maturation, which were harvested in March/April, May/June, and July/August, respectively. The fruits were analyzed to assess their pulp, peel, and seed proportions, and their levels of oil (pulp) and starch (seed). Results showed these six cultivars are good alternatives for oil extraction. Fuerte stands out as the most adequate for biodiesel production from pulp and seed due to its higher yield of oil and starch. The fruit cycle diversity of these cultivars might allow combining them for prolonged fruit production, both for fresh fruit marketing and biodiesel supply, as well as possibly using fruit pulp for oil extraction and seed starch for alcohol production.

Reação de híbridos de citros à inoculação com Alternaria alternata

RESUMO A mancha marrom de alternária (MMA), causada por Alternaria alternata, que produz uma toxina específica ao hospedeiro (Host Specific Toxin – HST) é uma doença de grande importância nos pomares de tangerinas no mundo. A doença afeta tangerinas, alguns de seus híbridos interespecíficos e pomelos, sendo que no Brasil, as principais variedades plantadas, a tangerina Ponkan e o tangor Murcott, são altamente suscetíveis ao fungo, que também é saprofítico alternativo, se reproduz nos pomares, sendo seus esporos facilmente disseminados pelo vento. Para esse trabalho, foram selecionados híbridos de citros, obtidos por cruzamentos dirigidos, por apresentarem características agronômicas que os tornam potenciais novas variedades de laranjas e tangerinas, tanto para a citricultura industrial, quanto de mesa. Esses híbridos foram avaliados quanto à resposta à MMA por meio da inoculação com A. alternata in vitro e in vivo, uma etapa imprescindível para a liberação de novas variedades. Foram selecionados mais de trinta genótipos resistentes ou que apresentaram poucos sintomas da doença. A seleção de variedades resistentes à doença é de grande importância econômica, pois além de diminuir os custos de produção, aumentados sobremaneira com a utilização do controle químico, contribui para a diminuição de inóculo no campo.

English

The goals of the present study were to identify resistant mandarin varieties with potential for the fresh fruit market that could enable an extension of the harvesting season and to develop appropriate methods to maintain fruit quality for longer storage periods. Fremont mandarin fruits were harvested at optimum maturity and stored with and without wax coating under different storage conditions: ambient (21 ± 2°C and 60 ± 5% relative humidity (R.H.)) and under refrigeration (8 ± 2°C and 90 ± 5% R.H.). Fruit physicochemical characteristics and acceptability and purchase intention, which were assessed through sensory analysis, were evaluated weekly. Mass loss was higher for fruits stored at ambient temperature. The soluble solids concentrations of fruits stored under refrigeration remained similar to the values measured at harvest. Fruits stored under refrigeration exhibited slightly higher gloss and color than fruits stored at ambient temperature. Wax-coated fruits exhibited lower mass loss and higher gloss and color than uncoated fruits. Similar results were observed for the sensory analysis: wax-coated fruits stored under refrigeration were better rated by panelists until the final evaluation (day 35 after the beginning of storage). Purchase intention was higher for fruits stored under refrigeration than at ambient temperature. It is concluded that uncoated fruits stored at ambient temperature exhibit a tendency to lose quality, which confirms the need for refrigeration and wax coating for post-harvest preservation of fresh citrus fruits. However, the physicochemical and sensory qualities of Fremont mandarins stored under refrigeration for 30 to 35 days are accepted by consumers.   Key words: Citrus spp., preservation, refrigerated storage, sensory analysis, post-harvest.

Consumer Acceptability of Fresh-Market Muscadine Grapes.

The objective of this research was to investigate the acceptability of muscadine grape (Vitis rotundifolia) genotypes (cultivars and selections) and to correlate overall liking to other quality measurements to determine the main drivers of liking. Twenty-two genotypes grown at the Univ. of Georgia-Tifton Campus were evaluated. Four retail commercial grape genotypes (Vitis vinifera and "Concord") were also evaluated for comparison. Panelists familiar with muscadine grapes used the hedonic general labeled magnitude scale (HgLMS, -100 = strongest disliking of any kind ever experienced, +100 = strongest liking of any kind ever experienced) to rate overall liking and the liking of appearance, flavor, pulp texture, and skin texture. Puncture testing was done to assess grape berry texture, and compositional attributes soluble solids and pH were also measured. The sensory results indicated that the grapes were variable with overall liking scores from 12.2 to 39.6. The factors highly correlated with overall liking scores were muscadine flavor, pulp and skin liking, while a significant negative correlation was found between skin liking and skin texture and mechanical texture measures. The muscadine grapes with the highest overall liking scores were Ga. 5-1-34 and Ga. 2-8-21. Principal component analysis confirmed that grapes with a thinner skin and a higher pH tended to group around overall liking and flavor points. These results indicate that even among panelists familiar with muscadine grapes, skin thickness is a negative characteristic. Breeding for thinner skins may be a positive step in muscadines gaining a more widespread appeal in the fresh fruit market.