Fruit Bagging Research Articles

WHOLE-CLUSTER BAGGING REDUCES SKIN FRECKLES ON 'TAINUNG NO. 2' PAPAYA FRUITS

Freckle-like blemishes occurring on ripe papaya fruits especially in cold season and it affecting the appearance on fruits leads to lower marketable prices. This study investigated the effect of 2 kinds of bagging materials, Tyvek and 100 g cm-2 base weights non-woven materials, as a whole-cluster bagging to reduce the incidence of skin freckles on ‘Tainung No. 2’ papaya fruits in southern Chinese Taipei. Sixty-one days after bagging, bagging treatments significantly reduced freckle index (FI) on papaya fruits, and it worked well throughout the period of the experiment. In addition, whole-cluster bagging treatments increased lightness and chroma of fruits skin showing a more aesthetic appearance than non-bagging treatment. However, fruits of the non-woven material bagging treatment were lower in soluble solid contents than those of the non-bagging control fruits but there was no significant difference with Tyvek treatment compared to the control. The results indicated that bagging whole-cluster fruit in Tyvek significantly reduced the skin freckles on papaya fruits, and bagging fruit 61 days before harvesting was necessary during the cold season in southern Chinese Taipei.

The Effect of Several Paper Bags on Fruit Skin Coloration of Red Skin European Pear ‘Kalle’

This study was conducted to elucidate the relationship between light and coloring and to obtain basic results for promoting redness expression in 'Kalle' (Pyrus communis L.) pear skin. It was investigated in location of anthocyanin layer by microscopic observation and differences in skin color expression of 'Kalle' bagged with paper bag which has different light transmittance rate and inside temperature. However, there was no anthocyanin layer in the brown skin and golden yellow color, anthocyanin layer was distributed in epidermins or hyperdermis of red skin pear and apple. Dark red colored 'Kalle' had more anthocyanin content, FW than light red colored apple 'Hongro'. Light transmittance rate of physical characteristics used paper bags was the highest in white paper bag, 42.2% and it also had more light quantity, than any other tested paper bags in specific wave length 650-655 nm. The maximum temperature of inner bag was higher about in yellow paper bag. The red coloration and anthocyanin contents in no bagged fruits were higher than in any other bagged fruit. However, red color expression among the bagged fruits was higher in white paper bag than in double layered black paper bag and yellow paper bag. Also, chromaticity value seemd to be a good index to explain variation of fruit skin color, because anthocyanin content and chromaticity value were higher. Based on these results, it is desirable to cultivate 'Kalle' without bag for stable redness expression but bagging is essential for decreasing damage by insect in Korea. Further examination to find suitable time of removing paperbag for redness expression and decreasing insect damage. In addition, it is required to develop paperbag whose transmittance rate is high in specific light wavelength or temperature of inner bags is low. Additional key words: anthocyanin, bagging, chromaticity value, light transmittance, Pyrus communis L.

Response of phenolic compounds in ‘Golden Delicious’ and ‘Red Delicious’ apples peel to fruit bagging and subsequent sunlight re-exposure

During the course of fruit development, the concentration of cyanidin-3-galactoside decreased in the peel of unbagged ‘Golden Delicious’ apples but increased in that of ‘Red Delicious’ apples. Fruit bagging completely inhibited the synthesis of cyanidin-3-galactoside in fruit peel. After re-exposure to sunlight for 9 days, ‘Golden Delicious’ synthesized an increased amount of anthocyanin compared to previously unbagged fruit, whereas ‘Red Delicious’ synthesized less than control. The concentration of quercetin-3-glycoside was also reduced during bagging treatment from the early developmental stage, but was enhanced after removing bags late in fruit development. However, the synthesis of the six types of flavonols, quercetin-3-galactoside, quercetin-3-glucoside, quercetin-3-rhamnoside, quercetin-3-rutinoside, quercetin-3-xyloside and quercetin-3-arabinoside, might possess different sensitivities to bagging treatment, as their concentrations increased at different levels compared to control. Chlorogenic acid in ‘Red Delicious’ apples and procyanidin B1 in ‘Golden Delicious’ had no response to bagging treatment while the former compound in ‘Golden Delicious’ and the latter in ‘Red Delicious’ did respond, suggesting that the regulation of the synthesis of these compounds by sunlight irradiation might be genotype dependent. Meanwhile, the response of other types of phenolic acids and flavanols as well as phloridzin to the bagging treatment was similar; their concentrations decreased with fruit bagging and then increased after bag removal, indicating that their synthesis regulation might be genotype independent.

Susceptibility of 15 Mango (Sapindales: Anacardiaceae) Cultivars to the Attack by <I>Anastrepha ludens</I> and <I>Anastrepha obliqua</I> (Diptera: Tephritidae) and the Role of Underdeveloped Fruit as Pest Reservoirs: Management Implications

We evaluated the susceptibility of 15 mango cultivars to the attack of Anastrepha ludens (Loew) and Anastrepha obliqua (Macquart) (Diptera: Tephritidae), the main tephritid pests of this crop in Mexico. In a field experiment, bagged fruit-bearing branches were exposed to gravid females of both fly species. Infestation rates, developmental time, adult eclosion, and F1 adult longevity, fecundity, and fertility were recorded, ranking cultivars in terms of susceptibility to fly attack and development. We also compared the volatile profile in selected resistant and susceptible cultivars in search of possible correlations. In a second experiment, clutch size for A. ludens was determined in each cultivar. Infestation rates, developmental time, and F1 demographic parameters varied sharply among cultivars and between fly species for bagged fruit. Cultivars 'Vishi,' '74-82,' and 'Brooks' were most susceptible to A. ludens infestation while "Tommy,' 'Sensation,' and 'Ataulfo "niño"' (parthenocarpic fruit) were most susceptible to A. obliqua infestation. 'Edward,' 'Kent,' 'Brooks late,' 'Palmer, and 'Ataulfo' exhibited tolerance to attack of both fly species. Fruit of susceptible and resistant cultivars exhibited unique volatile profiles. Fly development and F1 adult demographic parameters varied significantly among cultivars. A. ludens females laid larger clutches in larger and harder fruit. We highlight the important role of Ataulfo "niño" as pest reservoir if fruit is left unharvested on trees. We discuss the possible use of highly resistant cultivars as trap crops or egg sinks.

Impact of pre-harvest fruit-bagging with different coloured bags on peel colour and the incidence of insect pests, disease and storage disorders in ‘Royal Delicious’ apple

SummaryAn experiment was conducted to observe the effect of pre-harvest fruit bagging on ‘Royal Delicious’ apple (Malus x domestica Borkh.). On-tree fruit bagging was done using single-layer, non-woven spun-bound fabric bags of four different colours (light-yellow, blue, green, or red) on 15 July for 30 d before the expected date of harvest (15 August). The bags were removed 3 d before harvest (12 August) in each of two seasons (2010-11; 2011-12). All coloured bags had a significant influence on skin colour development and fruit quality attributes in ‘Royal Delicious’ apple. However, the light-yellow bags were most effective for the development of an attractive red peel colour (Hunter a* value = 52 ± 4.0). They also gave higher mean values for total anthocyanin concentration (TAC; 297.4 ± 21.9 mg cyanidin-3-glucoside kg 1 FW), phenylalanine ammonia lyase (PAL) activity (0.54 ± 0.03 µmol cinnamic acid produced min 1 g 1 FW), fruit firmness (38.6 ± 1.2 N), calcium concentration (5.38 ± 0.5 mg Ca2 100 g 1 DW), total phenolics concentration (TPC; 9.77 ± 0.25 mg gallic acid equivalents, 100 g 1 FW), anti-oxidant (AOX) activity (12.6 ± 0.35 µmol Trolox g 1 FW), soluble solids concentration (SSC; 14.5 ± 0.46 ºBrix), and ascorbic acid concentration (AAC; 29.3 ± 1.52 mg 100 1 g pulp) compared to blue, red, or green bags, or un-bagged apple fruit. Furthermore, light-yellow bags also resulted in the lowest incidence of San Jose scale insects (0.4 ± 0.2%) and diseases such as scab (1.03 ± 0.86%), fly speck (0.3 ± 0.3%), and sooty blotch (0.17 ± 0.15%) at harvest, and in storage disorders such as bitter pit, cork pit, and brown core. We therefore conclude that fruit bagging using single-layer, light-yellow non-woven, spun-bound fabric bags 30 d before harvest is beneficial for ‘Royal Delicious’ apple fruit colour and quality.

Pre-harvest fruit bagging: a useful approach for plant protection and improved post-harvest fruit quality – a review

SummarySeveral good agricultural practices (GAP) are becoming popular throughout the World for the production of high quality fruit with less dependence on man-made chemicals. Among such practices, pre-harvest fruit bagging has emerged as an effective method. Bagging is a physical protection method which not only improves the visual quality of fruit by promoting skin colouration and reducing blemishes, but can also change the micro-environment for fruit development, which can have several beneficial effects on internal fruit quality. Pre-harvest bagging of fruit can also reduce the incidence of disease, insect pest and/or mechanical damage, sunburn of the skin, fruit cracking, agrochemical residues on the fruit, and bird damage. Due to its many beneficial effects, fruit bagging has become an integral part of peach, apple, pear, grape, and loquat cultivation in Japan, Australia, China and the USA. Moreover, countries such as Mexico, Chile, and Argentina do not import apples unless they are bagged. Several studies have been conducted to identify the desirable effects of pre-harvest fruit bagging on skin colour development and quality, but contradictory results have been reported. These may be due to differences in the type of bag used, the stage of fruit development when bagged, the duration of fruit exposure to natural light following bag removal, and/or fruit- and cultivar-specific responses. Bagging is laborious and its cost:benefit ratio must be investigated in order to promote adoption of the method in much of the World. The aim of this review is to improve our understanding of the beneficial effects of bagging in different fruit by collecting otherwise scattered information so that more growers could consider using this method on a commercial scale.

Genome-wide transcriptome analysis of Chinese pollination-constant nonastringent persimmon fruit treated with ethanol

BackgroundThe persimmon Diospyros kaki Thunb. is an important commercial and deciduous fruit tree. The fruits have proanthocyanidin (PA) content of >25% of the dry weight and are astringent. PAs cause astringency that is often undesirable for human consumption; thus, the removal of astringency is an important practice in the persimmon industry. Soluble PAs can be converted to insoluble PAs by enclosing the fruit in a polyethylene bag containing diluted ethanol. The genomic resource development of the persimmon is delayed because of its large and complex genome. Second-generation sequencing is an efficient technique for generating huge sequences that can represent a large number of genes and their expression levels.ResultsWe used 454 sequencing for the de novo transcriptome assembly of persimmon fruit treated with 5% ethanol (Tr library) and without treatment as the control (Co library) to investigate the genes and pathways that control PA biosynthesis and other secondary metabolites. We obtained 374.6 Mb in clean nucleotides comprising 624,690 and 626,203 clean sequencing reads from the Tr and Co libraries, respectively. We also identified 83,898 unigenes; 54,719 (~65.2%) unigenes were annotated based on similarity searches with known proteins. Up to 14,954 of the unigenes were assigned to the protein database Clusters of Orthologous Groups (COG), 24,337 were assigned to the term annotation database of Gene Ontology (GO), and 45,506 were assigned to 200 pathways in the database of Kyoto Encyclopedia of Genes and Genomes (KEGG). The two libraries were compared to identify the differentially expressed unigenes. The expression levels of genes involved in PA biosynthesis and tannin coagulation were analysed, and some of them were verified using quantitative real time PCR (qRT-PCR).ConclusionsThis study provides abundant genomic data for persimmon and offers comprehensive sequence resources for persimmon research. The transcriptome dataset will improve our understanding of the molecular mechanisms of tannin coagulation and other biochemical processes in persimmons.

Transcriptome analysis of blood orange (Citrus sinensis) following fruit bagging treatment by digital gene expression profiling

SummaryBagging has been widely used in fruit crops to improve fruit quality. In this study, the internal qualities of blood orange (Citrus sinensis cv. ‘Tarocco’ ) fruit were significantly affected by bagging treatment. Total flavonoid (TFL) and total anthocyanin (TAN) concentrations increased, while total soluble solids (TSS), total phenolics (TPH), and ascorbic acid (AsA) concentrations and titratable acidity (TA) decreased in response to bagging treatment. To elucidate the molecular mode of action of bagging on fruit, high-throughput tag-sequencing (Tag-seq) analysis was used to analyse gene expression profiles in blood orange fruit in response to a bagging treatment. Over 21 × 106 total clean reads were obtained per library. Approx. 53.7 – 71.7% and 3.1 – 6.4% of the clean reads were mapped onto citrus genes or intergenic regions, respectively. However, approx. 25.2 – 39.9% of the clean reads failed to align with the citrus genome. Overall, bagging treatment resulted in an increase in transcripts involved in a range of metabolic pathways such as hormone synthesis and signalling, transcriptional regulation processes, the tricarboxylic acid (TCA) cycle, sucrose and starch metabolism, ascorbate metabolism, and the phenylpropanoid pathway, many of which are related to fruit quality. Analysis of the differentially expressed genes revealed that decreased TSS concentrations, TA, and AsA concentrations could mainly be attributed to the increased expression of genes involved in catabolic pathways, rather than in anabolic pathways. Competition for limited amounts of substrates for the flavonoid, phenolics, and anthocyanin pathways may have led to an increase in TAN and TFL concentrations, and a decrease in TPH concentration. In addition, our results showed that bagging treatment imposed a variety of stresses on fruit, thereby leading to an array of biochemical, physiological, and molecular changes. One gene (bHLH) that may be involved in anthocyanin biosynthesis in blood orange fruit has been identified and is discussed. These results reveal the extensive biochemical and genetic mechanisms operating in citrus fruit in response to a bagging treatment.

CONTROL DE FUMAGINA (Capnodium mangiferae Cooke & Brown) CON BIOFUNGICIDAS EN HOJAS Y FRUTOS DE MANGO “MANILA”

<p>Sooty mold <em>Capnodium mangiferae</em><strong> </strong>(Cooke & Broome) is one of the most important mango diseases in Mexico, after anthracnose (<em>Colletotrichum gloeosporioides </em>Penz.) and mango scab (<em>Elsinoe mangiferae </em>Bitanc. & Jenkins), affecting the yield and appearance of fruits. The effectiveness of seven organic fungicides, one synthetic fungicide, bagging of fruits and the untreated control were evaluated to control sooty mold on leaves and fruit of mango ‘Manila’, in Veracruz, Mexico. Results showed that the bio fungicides Bio hcaz 3.5, Bio fyb 1.5, Fungicus ph 4 y Fungicus ph 8 provided 95 % of leaves in the categories of healthy and light (less than 5 % damage). Percentage of healthy fruits was 98 % for bagging, 82 % for Benomil, 80 % for Sunset 3, 78 % for Sulfocop 4 and Bio fyb 1.5. Bio fyb 1.5 showed good control of sooty mold in leaves and fruits. The application of these organic products did not have a negative effect in the yield and fruits quality.</p><div id="gtx-trans" style="position: absolute; left: 263px; top: 100px;"> </div>

Assessment of rind quality of ‘Nules Clementine’ mandarin during postharvest storage: 1. Vis/NIRS PCA models and relationship with canopy position

This research was conducted to examine the relationships between fruit position in the canopy, limited light by fruit bagging, rind biochemical composition and susceptibility of ‘Nules Clementine’ mandarin to rind breakdown disorder (RBD) during storage. A secondary aim of this study was to explore diffuse reflectance visible and near infrared spectroscopy (Vis/NIRS) as a non-destructive technique to sort mandarin fruit based on preharvest canopy position. Vis/NIRS signals of fruit from four orchards in the Western Cape Province in South Africa (Citrusdal, Paarl, Porterville and Stellenbosch) were obtained using a LabSpec® spectrophotometer. In all four orchards, bagged fruit inside the canopy had significantly (p<0.001) higher incidence of RBD compared to unbagged outside fruit. Concomitant to this, bagged fruit inside the canopy had significantly higher postharvest weight loss and lower dry matter (DM) content in the rind tissue, suggesting involvement of these parameters in fruit susceptibility to RBD. Bagged fruit inside the canopy harvested from Porterville and Paarl had higher concentration of non-structural carbohydrates (fructose, glucose, and sucrose) than outside fruit without bagging. In Stellenbosch, fruit from the outside position without bags had lower rind sucrose (95.3mg/g DM) compared to inside bagged fruit (114.9mg/g DM) but higher glucose concentration (92.0mg/g DM) compared to inside bagged fruit (66.9mg/g DM). Principal component analysis (PCA) of Vis/NIRS signals was executed to separate fruit according to canopy position. The projection of the samples in the PCA score plots displayed clusters that allowed distinction between fruit from different preharvest treatments. The ability of PCA to discriminate inside and outside fruit using Vis/NIRS signal suggests the potential of this technology to discriminate fruit based on their susceptibility to RBD.

Chemical evaluation and effect of bagging new peach varieties introduced in southern Minas Gerais - Brazil

Brazilian peach production is insufficient for domestic supply. Aiming to increase production in the state of Minas Gerais, 16 new peach tree varieties were introduced in the Serra da Mantiqueira region and their fruit were analyzed for sugar, total phenol and total carotenoid contents by colorimetric methods, and for organic acid content by high-performance liquid chromatography. In addition, we examined the effect of fruit bagging on the levels of such constituents. To do so, the fruit of half the trees of each variety were bagged. The levels of sugars, phenols, carotenoids and organic acids are genotypic characteristics and significantly differed among varieties. Despite being a good form of fruit protection, providing better aspect and reducing the need for pesticides, bagging leads to lower contents of components such as sugars, phenols and organic acids in most varieties. However, it cannot be stated that this practice interferes with sensory characteristics. Knowledge of the chemical constituents of these new varieties allows determining those ideal for fresh consumption (e.g., “Maciel”, “Diamante”, “T. Beauty”, “Ouromel 2” and “C.1056”, among others) and those more suitable for industrial processing (e.g., “A. Gold”, “C.1122” and “C.1050”), as well as those which serve both purposes.

The effect of fruit bagging on the color, phenolic compounds and expression of the anthocyanin biosynthetic and regulatory genes on the ‘Granny Smith’ apples

In the Loess Plateau region of China, it was discovered that the famous green-skinned apple cultivar ‘Granny Smith’ could rapidly turn red following bag removal. In order to clarify the reasons for the color formation, we measured and analyzed the changes in anthocyanins, phenolic compounds and expression of the key anthocyanin biosynthetic and regulatory genes in the colored process of ‘Granny Smith’ apples. The results indicated that two types of anthocyanins (i.e., cyanidin 3-O-galactoside and cyanidin 3-O-arabinoside) could be detected in the skin of ‘Granny Smith’ apples after bag removal. Cyanidin 3-O-galactoside accounted for most of the total anthocyanin contents and significantly accumulated within 7 days, along with the concentrations of chlorophylls and carotenoids significantly decreasing. The concentrations of catechin and procyanidin B2 in bagged apples also noticeably decreased, while the concentration of epicatechin increased. After bag removal, the expression of MdDFR, MdANS and MdUFGT increased sharply within 7 days. The transcription level of MdMYB10 and MdBHLH33 was markedly up-regulated and peaked at 1 day. While in the non-bagged apples, little anthocyanins were found and the expression of those genes showed low levels and remained stable. Our results suggested that ‘Granny Smith’ apples, in the special growing conditions of the Loess Plateau region of China, had the potential ability of coloration. And the higher expression of MdDFR, MdANS, MdUFGT, MdMYB10 and MdBHLH33 genes could enhance anthocyanin accumulation on ‘Granny Smith’ apples.

봉지종류 및 괘대시기가 '원황' 및 '화산' 배 과실의 수확기 품질에 미치는 영향

봉지종류 및 괘대시기가 '원황' 및 '화산' 배 과실의 수확기 품질에 미치는 영향

EFFECT OF BAGGING ON THE COMPOSITION OF CARBOHYDRATE, ORGANIC ACID AND CAROTENOID CONTENTS IN MANGO FRUIT

The effect of fruit bagging on the content of carbohydrate, organic acid and carotenoid in ripening mango of cvs. 'Chinhuang', 'Baixiangya', 'Hongyu' and 'Guifei' was investigated by high performance liquid chromatography (HPLC). Fruit bagging enhanced the contents of both total carbohydrate and total carotenoid, but reduced the content of total organic acid in fruit of all the tested varieties. The composition of carbohydrate, carotenoid and organic acid were not affected by fruit bagging. Bagged fruits of all the tested varieties had higher content of ascorbic acid, quinin acid, β-carotene, xanthophyll and lycopene and each constituent of carbohydrate than the control fruit. The proportions of ascorbic acid, quinin acid, β-carotene and lycopene were all raised by fruit bagging. Content and/or proportions of other compositions of carbohydrate, organic acid and carotenoid in mango fruit varied with tested cultivars and constituent types. The resulted suggested that fruit bagging can improve the internal quality of mango.

The role of anthocyanin in photoprotection and its relationship with the xanthophyll cycle and the antioxidant system in apple peel depends on the light conditions

The synthesis of anthocyanin, the xanthophyll cycle, the antioxidant system and the production of active oxygen species (AOS) were compared between red and non-red apple cultivars, in response to either long-term sunlight exposure (high light intensity) during fruit development, or to exposure of bagged fruits to lower light intensity late in fruit development. During fruit development of red and non-red apples, the xanthophyll cycle pool size decreased much more in red apple peel late in development. With accumulation of AOS induced by long-term sunlight exposure, enhancement of the antioxidant system was found. However, this change became significantly lower in red apple than non-red apple as fruit developed, which might serve to accelerate the anthocyanin synthesis in red apple peel. When, late in fruit development, bagged fruits were exposed to sunlight, the accumulation of AOS was lower in red apple peel than in non-red peel. This could be due to the higher anthocyanin concentration in the red peels. Meanwhile, compared with that in non-red cultivar, the xanthophyll cycle and the antioxidant system in red apple peel were protected first but then down-regulated by its higher anthocyanin concentration during sunlight exposure. In conclusions, red and non-red apples peel possess different photoprotective mechanisms under high light conditions. The relationship between anthocyanin synthesis and the xanthophyll cycle, and the antioxidant system, depends on the light conditions that fruit undergoes.

Pre-harvest fruit bagging influences fruit color and quality of apple cv. Delicious

An attempt was made to observe the effect of pre-harvest bagging with spun-bound fabric bags on color and quality of Delicious apple. Bagging was done about a month before harvesting and removed 3-day before harvesting. Bagged and non-bagged fruits were stored at 2℃ ± 1℃ and 90%-95% RH. Observations were recorded on color and fruit quality attributes such as total phenolics, AOX activity, fruit Ca contents, LOX activity, SSC and ascorbic acid contents at harvest and during storage. Our studies have revealed that bagged fruits have better color development (Hunter “a” = 52) than non-bagged fruits at harvest (Hunter “a” = 38), which declined slightly during storage. Similarly, at harvest, bagged fruits contained high amounts of Ca (5.38 mg/100g) and total phenolics (9.3 mg GAE/100gpulp) exhibited higher AOX activity (12.6 μmoles Trolox g-1), and had better SSC and ascorbic acid contents than non-bagged fruits, and there was a decline in all recorded parameters during storage. Bagged fruits exhibited lower LOX activity (1.38 μmoles min-1 g-1 FW) at harvest than non-bagged fruits (2.14 μmoles min-1 g-1 FW), indicating that non-bagged fruits were more senescent than bagged fruits. Further, LOX activity increased during storage both in bagged and non-bagged apples but increase in LOX activity was slower in bagged apples than in non-bagged apples.

Influence of bagging on fruit quality and mineral composition of Himsagar mango grown in new alluvial zones of West Bengal

The effect of polybagging of mango (Mangifera indica L.) fruits was evaluated at different stages of fruit development (35, 45, 55 and 65 days after fruit set). Fruits were harvested at different stages of maturity (75, 85 and 90 days after fruit set) and allowed to ripen at room temperature (34-36°C, RH 85-90%). The use of bagging at different stages of fruit development improved the appearance of fruit, fruit weight and size through other effects such as increased relative humidity and a consequently reduced fruit water loss. The maturity of fruits, at all stages of fruit harvest, was delayed with increasing bagging duration. Early bagging of fruit (35 days after fruit set) delayed the development of ripening characteristics in comparison to delayed bagging and unbagged control fruit, which ripened earliest. This was clearly evident from the carotene content in the mango flesh, at the different stages of harvest and of ripening fruit, which was the result of higher temperature inside the bags. In bagged fruits usually day/night temperature fluctuations were reduced and there was a cut off in the temperature curve inside the bag. The total soluble solids and sugar content were higher and titratable acid content was always less in unbagged fruit at all stages of fruit harvest and fruit ripening. Mineral elements were also affected by the number of days of bagging. The reduced Ca concentration in long-duration bagging (early bagging) might be due to increased RH around the fruits. Fruits bagged for 55 days recorded an increased content of N, P, Zn, Mn and Fe while fruit calcium concentration was reduced by bagging for 55 days. Anthracnose and stem-end-rot (SER) caused by Colletotrichum and Diplodia spp. Respectively were reduced by bagging in both years through a reduction in contact between disease propagules and fruits. These results indicate that bagging can improve fruit quality by reducing disease, lead to a better appearance of fruit and increase fruit weight and size.

Effects of fruit bagging on anthocyanins, sugars, organic acids, and color properties of ‘Granny Smith’ and ‘Golden Delicious’ during fruit maturation

The effects of fruit bagging on anthocyanins, sugars, organic acids, and color properties of ‘Granny Smith’ and ‘Golden Delicious’ were investigated in this study. Young fruits were bagged 40 days after flowering (DAF) with paper bags. The bagged fruits of ‘Golden Delicious’ were uncovered and exposed to light 120 DAF, while those of ‘Granny Smith’ 160 DAF. The fruits were harvested after 0, 2, 4, 6, 8, 10, and 15 day of bag removal, respectively. The development of anthocyanins, sugars, organic acids, and color properties in the flesh of ‘Granny Smith’ and ‘Golden Delicious’ was determined. After bag removal, the ‘Granny Smith’ and ‘Golden Delicious’ turn red, a* was consequently augmented, while L*, b*, C*, and h0 reduced. Cyanidin 3-galactoside and cyaniding 3-arabinoside were identified in ‘Granny Smith’ and ‘Golden Delicious’ as the two constituents responsible for red color of apple peel, and with cyanidin 3-galactoside being the most abundant anthocyanin in these non-red cultivars. Fructose, sucrose, and sorbitol were the major sugars and sugar alcohol, and malic acid was the major organic acid. Concentrations of most sugars and all organic acids quickly increased during 0–4 DABR, suggesting that synthesis of these sugars and organic acids was inhibited by fruit bagging. Furthermore, the cy3-gal and cy3-ara accumulation of all tested cultivars was significantly correlated with sucrose, indicating that sucrose may be the more important factors in the biosynthesis of anthocyanin.

KAOLIN SPRAYS AND INDIVIDUAL FRUIT BAGGING EFFECTS ON QUINCE FRUIT QUALITY

ISHS XXVIII International Horticultural Congress on Science and Horticulture for People (IHC2010): International Symposium on the Challenge for a Sustainable Production, Protection and Consumption of Mediterranean Fruits and Nuts KAOLIN SPRAYS AND INDIVIDUAL FRUIT BAGGING EFFECTS ON QUINCE FRUIT QUALITY

Irradiation as a postharvest quarantine treatment for a new pluot cultivar

The effects of irradiation treatment on the quality of ‘Flavor Fall’ pluots (Prunus salicina×armeniaca Lindl.) were tested to determine if this is a feasible alternative postharvest mitigation treatment to disinfest fruit of quarantine pests. Packed cartons of fruit were treated with three doses of irradiation (400, 900 and 1400Gy) where after the fruit was cold stored for 42d with a dual temperature regime and then 7d to simulate shelf-life conditions. The effect of two different bag types used inside the carton was also tested; a high density polyethylene perforated bag used commercially to package grapes, and a low-density polyethylene insect-proof bag with much smaller perforations. Respiration rates and ethylene production were determined at various time points during the trial, and quality parameters such as hue angle, shrivel, flesh firmness, decay and gel breakdown were measured throughout the process. The results indicated that the respiration rate of the fruit generally increased as the irradiation dose increased, except after shelf-life where it decreased after reaching a maximum at 400Gy. Even at the highest dose most of the quality parameters measured at the end of cold storage were above the minimum arrival standards for overseas markets, except for shrivel, a condition that is common in the ‘Flavor Fall’ cultivar. Shrivel was higher than the maximum allowed, and although fruit contained in the insect-proof bags had half the amount of shrivel than fruit in the commercial bag, it was still above the maximum 10% allowed for export fruit. After further optimization of the approach, a system using insect-proof bags and irradiation would be an effective non-toxic alternative to currently used mitigation treatments for plums.