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1.
Pestic Biochem Physiol ; 165: 104505, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32359555

RESUMEN

Blue mold caused by Penicillium italicum is an important postharvest disease of citrus fruit. The antifungal activity of a flavonone pinocembroside compound obtained from the fruit of Ficus hirta Vahl., was evaluated against P. italicum. Pinocembroside showed antifungal activity against in vitro mycelial growth of P. italicum, with the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of 200 and 800 mg/L, respectively. The blue mold development on 'Newhall' navel oranges was inhibited by pinocembroside in a dose-dependent manner. Moreover, pinocembroside might exert its antifungal activity via membrane-targeted mechanism with increasing membrane permeability, reduction of antioxidant enzyme activity and acceleration of lipid peroxidation in the pathogen. This pioneering study suggested that pinocembroside suppressed postharvest blue mold by direct inhibition of P. italicum mycelial growth via membrane-targeting mechanism, thus providing a novel mode of action against traditional fungicides for controlling blue mold of citrus fruit.


Asunto(s)
Citrus sinensis , Citrus , Fungicidas Industriales , Penicillium , Frutas
2.
Oecologia ; 193(1): 189-198, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32405932

RESUMEN

While functional traits can facilitate or constrain interactions between pair of species in ecological communities, relative abundances regulate the probabilities of encounter among individuals. However, the relative importance of traits and relative abundances for the role species play in seed dispersion networks remains poorly explored. Here, we analyzed 20 Neotropical seed dispersal networks distributed from Mexico to southeastern Brazil to evaluate how relative abundance and functional traits influence bat species' roles in seed dispersal networks. We tested how bat relative abundance and traits relate to species contribution to between-module (c metric) and within-module connectivity (z metric) and their position and potential to mediate indirect effects between species (betweenness centrality). Our results indicate that relative abundance is the main determinant of the role bats play in the networks, while traits such as aspect ratio show modest yet statistically significant importance in predicting specific roles. Moreover, all seed dispersal networks presented two or three superabundant obligatory frugivore species that interacted with a high number of plants. The modest influence of the functional traits on species' roles is likely related to the low variation of morphological traits related to foraging ecology, which reduces the chances of morphological mismatching between consumers and resources in the system. In this scenario, abundant bats have higher chances of encountering resources and being capable of consuming them which leads such species to play critical roles in the community by acting as module hubs and network connectors.


Asunto(s)
Quirópteros , Dispersión de Semillas , Animales , Aves , Brasil , Ecosistema , Frutas , México , Semillas
3.
Phytochemistry ; 174: 112364, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32247075

RESUMEN

Ten undescribed dihydrochalcone C-glycosides, carambolasides R1‒R3, S1, S2, T1‒T3, 3-hydroxycarambolaside T1, and 3-hydroxycarambolaside P were isolated along with carambolasides I and P from the leaves of Averrhoa carambola L. (Oxalidaceae). Their structures were determined by spectroscopic and chemical methods. Among them, carambolasides P, T1, T2, and I with contents of 22.78, 14.39, 4.93, and 1.87 mg g-1 dry wt., respectively, were shown to be abundant in the leaves by HPLC analysis. All the compounds showed more potent ABTS radical cation scavenging activity than l-ascorbic acid. 3-Hydroxycarambolaside T1 and 3-hydroxycarambolaside P also demonstrated moderate DPPH radical scavenging activity. Further, carambolaside R3, 3-hydroxycarambolaside T1, and 3-hydroxycarambolaside P exhibited weak in vitro porcine pancreatic lipase inhibitory activity.


Asunto(s)
Averrhoa , Animales , Antioxidantes , Chalconas , Frutas , Glicósidos , Extractos Vegetales , Hojas de la Planta , Porcinos
6.
J Cosmet Sci ; 71(1): 11-22, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32271705

RESUMEN

Darkening of fruits is the result of the oxidative activation of polyphenol oxidase converting low-molecular weight phenols present in the fruit body into quinone intermediates. Then, through polymerization, these reactive quinones convert to light yellow and red low-molecular weight melanin and, given enough time, to darker, higher molecular weight brown and black melanin. The process that occurs in the flesh of cut fruit is very similar to the process that human skin cells use to make melanin: the oxidative activation of tyrosinase and conversion of tyrosine to dopaquinone and eventually to darker melanin. The conversion of the phenols by tyrosinase to quinones is the rate-limiting step in the biochemical manufacture of melanin. This article will discuss a new and cost effective way to screen skin-brightening ingredients by the use of apple slices as a model for skin using a chromameter to measure the change in color that occurs in apple slices over a short time course. Such measurements have been popularly used by food manufacturers to examine ingredients that inhibit fruit browning. Interestingly, as will be noted, many of the ingredients used commercially to inhibit food browning are also popular skin-brightening ingredients. We have found that a DermaLab (Cortex Technologies, Hadsund, Denmark) chromameter measuring the erythema index of apple slice darkening appears to be able to differentiate the benefit of a formulation containing azelaic acid, a known skin-lightening ingredient, to minimize the darkening effects that occur in sliced apples. We will discuss how different apples behave differently when cut and how to best use the chromameter to analyze the changes that occur that can potentially help rapidly screen ingredients for their skin-brightening benefits.


Asunto(s)
Malus , Frutas , Humanos , Reacción de Maillard , Monofenol Monooxigenasa , Fenoles
7.
Zootaxa ; 4758(1): zootaxa.4758.1.11, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-32230163

RESUMEN

Jujube Ziziphus jujuba Mill. (Rhamnaceae), known as "Ber" in India, is an evergreen thorny shrub with reddish-brown fruits, chiefly found in Southeast Asia (Reza 2014). Up to now three species of gall midges have been associated with jujube: Phyllodiplosis jujubae Grover Bakshi, and Silvestrina jujubae Chandra in India and Dasineura jujubifolia Jiao Bu in China (Grover Bakhshi 1978; Chandra 1988; Jiao et al. 2017). Between 2015 and 2018 during field trips by DV VRP to Singanallur lake area, Coimbatore, Tamil Nadu, one of us (DV) noticed and collected leaves of Z. jujuba containing small galls on the midrib region of leaves. In the laboratory the leaves were dissected, and causative agent identified as a gall midge. The adults were reared and identified as undescribed species of gall midge, here described and named Asphondylia singanallurensis Vasanthakumar Sharma. Type specimens were processed and mounted in Canada balsam as per the method in Kolesik et al. (2015). Holotype and paratypes were prepared and deposited in the collection of the Zoological Survey of India, WRC, Pune.


Asunto(s)
Dípteros , Rhamnaceae , Ziziphus , Animales , Frutas , India , Hojas de la Planta
8.
Int J Syst Evol Microbiol ; 70(3): 1585-1590, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32228772

RESUMEN

A novel lactic acid bacterium, strain MB7T, was isolated from lychee in Taiwan. MB7T is Gram-staining-positive, catalase-negative, non-motile, non-haemolytic, facultatively anaerobic, coccoid-shaped, heterofermentative and mainly produces d-lactic acid from glucose. Comparative analysis of 16S rRNA, pheS and rpoA gene sequences has demonstrated that the novel strain represented a member of the genus Leuconostoc. 16S rRNA gene sequencing results indicated that MB7T had the same sequence similarity of 99.25 % to four type strains of members of the genus Leuconostoc: Leuconostoc mesenteroides subsp. dextranicum DSM 20484T, Leuconostoc mesenteroides subsp. jonggajibkimchii DRC 1506T, Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293T and Leuconostoc suionicum DSM 20241T. Additionally, high 16S rRNA sequence similarities were also observed with Leuconostoc mesenteroides subsp. cremoris ATCC 19254T (99.12 %) and Leuconostoc pseudomesenteroides NRIC 1777T (98.69 %). When comparing the genomes of these type strains, the average nucleotide identity values and digital DNA-DNA hybridization values of MB7T with these type strains were 76.57-80.53 and 22.0-22.6 %, respectively. MB7T also showed different phenotypic characteristics to other most closely related species of the genus Leuconostoc, such as carbohydrate metabolizing ability, halotolerance and growth at various pHs. On the basis of phenotypic and genotypic properties, strain MB7T represents a novel species belonging to the genus Leuconostoc, for which the name Leuconostoc litchii sp. nov. is proposed. The type strain is MB7T (=BCRC 81077T=NBRC 113542T).


Asunto(s)
Frutas/microbiología , Leuconostoc/clasificación , Litchi/microbiología , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Fermentación , Ácido Láctico , Leuconostoc/aislamiento & purificación , Leuconostoc mesenteroides , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Taiwán
9.
Zhongguo Zhong Yao Za Zhi ; 45(6): 1334-1341, 2020 Mar.
Artículo en Chino | MEDLINE | ID: mdl-32281345

RESUMEN

In order to understand the structural characteristics of squalene synthase genes in the triterpenoids biosynthesis pathway of Crataegus pinnatifida, the squalene synthase genes of C. pinnatifida was cloned and analyzed by bioinformatics and prokaryotic expression. Two squalene synthase genes CpSQS1 and CpSQS2 were cloned from C. pinnatifida fruit by RT-PCR. The ORF length of CpSQS1 and CpSQS2 were 1 239 bp and 1 233 bp respectively, encoding 412 aa and 410 aa respectively. CpSQS1 and CpSQS2 were predicted to be stable acidic proteins by online tools. The secondary structure was mainly composed of α-helix structure, and the tertiary structure was predicted by homology modeling. Structural functional domain analysis showed that 35-367 aa of CpSQS1 and CpSQS2 cDNA containing conserved trans-isoprenyl pyrophosphate synthase domains. Transmembrane domain analysis predicted that two transmembrane domains were founded in CpSQS1 and CpSQS2. The squalene synthase amino sequence of C. pinnatifida had higher homology with the known SQS of Salvia miltiorrhiza and Glycyrrhiza glabra. Phylogenetic tree analysis showed that CpSQS1 and CpSQS2 were clustered into one branch of MdSQS1 and MdSQS2, which were consistent with the phylogenetic rule. Prokaryotic expression vector pGEX-4 T-1-CpSQS1 and pGEX-4 T-1-CpSQS2 were transformed into Escherichia coli Transetta(DE3) for induction, and the target protein was successfully expressed at 65 kDa. The expression levels of CpSQS2 were significantly higher than that of CpSQS1 in three different developmental stages of C. pinnatifida. In this study, the full-length cDNA sequences of C. pinnatifida SQS1 and SQS2 were cloned and analyzed for the first time, which provided the foundation for further study on the metabolic pathway of C. pinnatifida triterpenoids.


Asunto(s)
Crataegus/enzimología , Farnesil Difosfato Farnesil Transferasa/genética , Proteínas de Plantas/genética , Secuencia de Aminoácidos , Clonación Molecular , Crataegus/genética , Frutas/enzimología , Filogenia
10.
Nutrients ; 12(4)2020 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-32252221

RESUMEN

While the medical community supports the growth of citrus consumption as part of a healthy diet, there is limited knowledge about consumer preferences for these fruits. The current study analyzed the purchasing patterns and drivers of fresh citrus fruits from a convenience sample of 346 Italian food shoppers. Results revealed that clementines were the citrus fruit purchased most, followed by oranges and tangerines. Sweetness and smell were important product attributes for respondents. Different drivers affect the purchasing frequencies of various citrus fruits. Taste motivation, with a specific preference for acidity, impacts orange purchasing. Similarly, clementines are purchased primarily for taste motivation, however, the core sensory attribute for respondents in this case was sweetness. Meanwhile, for tangerines, the taste motivation is less important than the energy motivation, and the size together with the color are the core purchasing drivers. These outcomes provide food scientists, agronomists and market practitioners with new insights into Italian consumers' preferences for citrus fruits, thus contributing to a potential expansion of this market.


Asunto(s)
Citrus , Comercio , Comportamiento del Consumidor , Preferencias Alimentarias , Percepción del Gusto , Comportamiento del Consumidor/estadística & datos numéricos , Frutas , Humanos , Italia , Olfato , Gusto
11.
J Environ Manage ; 265: 110510, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32275240

RESUMEN

Valorization of Fruit and Vegetable Wastes (FVW) is challenging owing to logistic-related problems, as well as to their perishable nature and heterogeneity, among other factors. In this work, the main existing routes for food waste valorization are critically reviewed. The study focuses on FVW because they constitute an important potential source for valuable natural products and chemicals. It can be concluded that FVW management can be carried out following different processing routes, though nowadays the best solution is to find an adequate balance between conventional waste management methods and some emerging valorization technologies. Presently, both conventional and emerging technologies must be considered in a coordinated manner to enable an integral management of FVW. By doing so, impacts on food safety and on the environment can be minimized whilst wasting of natural resources is avoided. Depending on the characteristics of FVW and on the existing market demand, the most relevant valorization options are extraction of bioactive compounds, production of enzymes and exopolysaccharides, synthesis of bioplastics and biopolymers and production of biofuels. The most efficient emergent processing technologies must be promoted in the long term, in detriment of the conventional ones used nowadays. In consequence, future integral valorization of FVW will probably comprise two stages: direct processing of FVW into value-added products, followed by processing of the residual streams, byproducts and leftover matter by means of conventional waste management technologies.


Asunto(s)
Eliminación de Residuos , Administración de Residuos , Biocombustibles , Frutas , Verduras
12.
J Environ Manage ; 262: 110320, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32250803

RESUMEN

Deficit irrigation (DI) and plant growth regulators (PGRs) have strategic role for sustaining crop productivity and mitigating water stress in drought prone areas. However, their impacts are yet to be quantified for eggplant (Solanum melongena L.), a popular drought tolerant vegetable crop grown in water scarce Deccan Plateau of India. We conducted field experiments during 2016-17 and 2017-18 in a drought prone region of Deccan Plateau, India to evaluate the interactive effect of PGRs viz., 1.38 mg L-1 salicylic acid (SA), 1.5% potassium nitrate (PN), 500 ppm thio-urea (TU) and 100 ml L-1 bio-stimulant (BS) and varied levels of DI generated using line source sprinkler system. The marketable fruit yields were reduced to 86, 74, 50, 30, 12 and 8% with increased level of DI i.e. when the applied irrigation water (IW) equalled 0.00, 0.15, 0.30, 0.45, 0.60 and 0.75 times the cumulative open pan evaporation (CPE) against the recommended irrigation practice (IW:CPE 0.90). Application of PGRs improved fruit yields by 7.3-22.7% and their role to alleviate water stress was indicated by lower canopy temperatures, maintaining higher leaf relative water content, modulation of stomatal opening and higher consumptive use of water. Particularly SA and TU were superior under low to medium water stress (IW:CPE 0.45-0.75) whereas PN was effective in severe water stress (IW:CPE 0.0-0.44) while the effect of BS was almost similar with PGRs like TU under medium stress conditions. The maximum water productivity (WP) varied between 5.50 and 6.77 kg m-3 for different PGRs and it was 5.16 kg m-3 without PGRs indicating water savings to the order of 28.8-57.4% with the former. The fruit quality attributes such as mean diameter, sphericity, fruit weight and firmness traits declined with water stress while these were considerably rectified with PGRs. Higher accumulation of dry matter, sugar, protein, total phenolics, flavonoids and improved rehydration quality as well as potentially affecting enzymatic activity were monitored with PGRs. It is concluded that exogenous application of PGRs like SA and PN along with medium levels of DI can help in rational utilization of water resources and could effectively improve yield and post-harvest quality of eggplant fruits especially under water scarce environment of Deccan Plateau.


Asunto(s)
Solanum melongena , Frutas , India , Reguladores del Crecimiento de las Plantas , Agua
13.
Waste Manag ; 107: 143-149, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32283488

RESUMEN

Brazil stands out as one of the largest world powers in the agribusiness sector, and with the increase of production capacity, an enormous amount of waste is generated that cause serious environmental problems. Acerola is evidenced as one of the fruits of growing and important commercialization, contributing significantly to regional development through the export of concentrated powder product. Thus, in order to minimize the environmental impacts generated by the local fruit processing industry, the proximate analysis of its residue after drying in a convective oven at temperatures of 50, 75 and 100 °C was carried out in this work, aiming at the reuse of this residue for thermochemical processes. Moisture, ash, volatile matter (VM), and fixed carbon (FC) content were analyzed, as well as characterizations, such as infrared spectroscopy (FTIR), elemental analysis (CHNO), calorific value (HHV) and thermogravimetry (TG/DTG). The results showed a significant difference in the moisture contents, VM, FC and elemental carbon for the dry residue at 50 °C compared to the temperatures of 75 and 100 °C, while for the ash content there was no significant difference between the temperatures. The dry acerola residue at the three temperatures studied presented adequate properties for thermochemical application, with lignocellulosic compounds that can be converted by thermochemical route, good levels of calorific power, low moisture and ash content, associated with high amount of volatile matter.


Asunto(s)
Ácido Ascórbico , Residuos Industriales , Brasil , Frutas , Termogravimetría
14.
Medicine (Baltimore) ; 99(10): e19469, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32150106

RESUMEN

The profiles of sensitization based on component-resolved diagnosis (CRD) differ from region to region in populations sensitized to birch pollen. We investigated the endotypes of birch pollen-sensitized Korean children with allergic diseases using CRD and distinguished the endotypes of oral allergy syndrome (OAS) among them.Thirty-one birch pollen-sensitized children with allergic diseases were enrolled. Specific immunoglobulin E (IgE) to birch pollen and fruit including apple, peach, and kiwi were evaluated via skin prick tests and ImmunoCAP in all subjects. Sensitization profiles based on CRD were evaluated with the Immuno-solid-phase Allergen Chip for birch pollen-sensitization using birch pollen components (Bet v 1, Bet v 2, and Bet v 4), and for OAS using the allergen families pathogenesis-related class 10 proteins (PR-10), lipid transfer proteins, and profilin.All patients (n = 13) with OAS were sensitive to Bet v 1. However, 61% (11/18) of patients without OAS were sensitized to Bet v 1. The level of specific IgE to Bet v 1 was higher in patients with OAS than in those without OAS. All birch pollen-sensitized Korean children with OAS were sensitized to PR-10, and 69% (9/13) of them were mono-sensitized to PR-10. Among patients without OAS, 33% (6/18) were not sensitized to any of the allergen families.Birch pollen-sensitized Korean children with allergic diseases showed unique patterns of sensitization to Bet v 1, Bet v 2, and Bet v 4, and the sensitization profiles based on CRD were totally different according to the presence of OAS.


Asunto(s)
Alérgenos/inmunología , Betula/inmunología , Hipersensibilidad a los Alimentos/inmunología , Polen/inmunología , Adolescente , Niño , Preescolar , Reacciones Cruzadas , Femenino , Hipersensibilidad a los Alimentos/complicaciones , Frutas/inmunología , Humanos , Masculino , Reproducibilidad de los Resultados , República de Corea , Sensibilidad y Especificidad , Pruebas Cutáneas
15.
Phytochemistry ; 174: 112345, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32200067

RESUMEN

Ten poly-O-acylated ß-dihydroagarofuran sesquiterpenoids, siphonagarofurans A-J, were obtained from the fruits of Siphonodon celastrineus using chromatographic techniques. Their structures were elucidated by extensive use of 2-D NMR spectroscopic methods. The absolute configurations of siphonagarofurans A-J were assigned following analysis of calculated and experimental ECD spectra. The absolute configuration of siphonagarofuran A was also confirmed by X-ray crystallographic analysis. Selected compounds were evaluated for their cytotoxic activity against KB, Vero and Hela cell lines with siphonagarofuran J identified as the most active compound, with IC50 values ranging from 14 to 27 µM.


Asunto(s)
Celastraceae , Sesquiterpenos , Frutas , Células HeLa , Humanos
16.
Environ Monit Assess ; 192(4): 248, 2020 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-32206905

RESUMEN

Biosorption of Cr(VI) on sulfuric and phosphoric acid-treated Datura stramonium fruit was investigated in batch mode. The various parameters that influence the biosorption process such as Cr(VI) initial concentration, biosorbent dosage, contact time, temperature, and pH value were optimized. Both linear and non-linear regression analysis of isotherm data suggest that Langmuir isotherm model mimics the behavior of Cr(VI) ion biosorption onto Datura stramonium fruit biosorbent. The maximum Cr(VI) ions adsorption capacity of 138.074 mg/g at pH 2 is achieved with phosphoric acid treated Datura stramonium (PDSF). The kinetics of adsorption process is well described by pseudo-second-order model with high R2 and low χ2 value. The estimated activation energy of < 8 kJ/mol obtained for both raw and chemically modified adsorbents suggests that the adsorption occurs mainly via physisorption. Besides, thermodynamic results reveal that biosorption of Cr(VI) on both treated and untreated Datura stramonium was endothermic, spontaneous, and randomness in nature.


Asunto(s)
Cromo , Datura stramonium , Frutas , Contaminantes Químicos del Agua , Adsorción , Cromo/análisis , Datura stramonium/química , Monitoreo del Ambiente , Frutas/química , Concentración de Iones de Hidrógeno , Cinética , Modelos Teóricos , Termodinámica
17.
Plant Dis ; 104(5): 1433-1438, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32155113

RESUMEN

Since the 2000s, production of pitahaya (Hylocereus spp.) has increased significantly in South Florida. However, very limited information is available on the main diseases affecting this crop, particularly in regard to disease epidemiology and economic impact on the commodity. In this study, we surveyed five local pitahaya orchards and documented the most prevalent diseases and their causal agents. Three genera of fungal pathogens (Neoscytalidium, Alternaria, and Colletotrichum) were the major groups associated with symptoms on pitahaya cladodes (stems) during the early growing season. Among these, N. dimidiatum was identified as the most prevalent pathogen, with an overall isolation frequency of 29.8% (range, 13.9 to 47.2%). Hence, the temporal progress of N. dimidiatum stem canker infection was monitored and the relationship between stem canker intensity (incidence and severity) and fruit canker incidence was investigated. A significant positive correlation was found between fruit canker incidence and the standardized area under the disease incidence or severity curve on cladodes, suggesting that high stem canker intensity in the early season may contribute to high fruit canker incidence and thereby impact the aesthetic and market value of fruits. In vitro assays showed that both conidial germination and mycelial growth of N. dimidiatum are positively correlated with increasing temperature, with a maximum growth area at 32°C. This finding suggests a higher risk of infection, under an environment with high temperatures, which is common in South Florida. Data obtained in this study represent baseline knowledge for the future development of integrative management programs for controlling major diseases of pitahaya in South Florida.


Asunto(s)
Epidemias , Frutas , Florida , Enfermedades de las Plantas , Prevalencia
18.
Plant Dis ; 104(5): 1274-1279, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32213125

RESUMEN

In the southeastern United States, Armillaria root rot (ARR) is caused by Desarmillaria tabescens and has become the primary cause of premature mortality in peach orchards. Most rootstocks used in commercial orchards are susceptible and management options are limited. A postinfection practice known as root-collar excavation (RCE), which involves permanent removal of the soil from the base of the trunk, has been shown to improve yields and prolong the productive life of symptomatic trees. However, symptomatic trees already have an advanced infection at the base of the trunk. This study evaluated the efficacy of preventative RCE on the progression of tree mortality in two orchards that were planted in infested replant sites. To provide convincing data for growers, the study was carried out in a commercial orchard and an experimental orchard for 8 years. Furthermore, representative enterprise budgets and net present value (NPV) analysis were utilized to compare the profitability of the two approaches. Trees were planted shallow on berms (45 by 90 cm) to facilitate RCE with hoes and AirSpade 2 years later. Tree mortality in the RCE treatment of the experimental orchard was first observed in year 6 and increased 8% on average per year thereafter. In contrast, tree mortality in the "Grower Standard" treatment was first observed in year 4 and increased 12.7% on average per year thereafter. At the commercial orchard, tree mortality in the RCE treatment was first observed in year 7 and increased 1.9% on average thereafter, while tree mortality in the Grower Standard treatment first appeared in year 5 and increased 4.3% on average thereafter. The delayed onset of ARR-associated tree mortality and the lower annual tree mortality rate in the RCE treatment led to higher NPVs in both locations. There were no negative effects on yield or fruit quality. However, the new planting system can create horticultural challenges, including the formation of a proper berm, uneven ground around the tree interfering with tree care and harvest, increased erosion due to channeling of rainwater, and increased rootstock suckering. The RCE is a valid option for southeastern growers needing to manage high ARR disease pressure on replant sites or on sites only recently cleared from ARR-infected forest land.


Asunto(s)
Armillaria , Prunus persica , Frutas , Suelo , Sudeste de Estados Unidos
19.
Int J Food Microbiol ; 322: 108575, 2020 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-32155515

RESUMEN

Apple is a major crop in Argentina where 50% of the production is derived to by-products. Industries process either recently harvested apples or fruit stored for up to 9 months. This crop is susceptible to fungal diseases both external and internal, such as mouldy core (MC). The incidence of fungal pathogens changes during storage, as well as the risk associated with their presence since some contaminants belong to mycotoxigenic genera. The objective of this study was to characterize the fungal contaminants of Red Delicious apple fruit in Argentina evaluating their evolvement from field to process, with main interest on MC causal agents and mycotoxigenic species. A total of 240 apples were analysed; 140, recently harvested and intended for fresh consumption (C), and 100 stored for 9 months in a refrigerated chamber (0-3 °C) and destined to industrialization (I). The 86% of fresh consumption apples showed external fungal lesions, and only 14% were undamaged; MC incidence was 34%. High biodiversity was observed; Penicillium was the predominant genus (54%), followed by Alternaria spp. (41%). Only 3% of industrialization fruit were undamaged, 48% had external lesions and 51% MC. However, biodiversity was lower in these apples. Alternaria spp. was recovered from 60% of apples, mainly causing MC, while Penicillium spp. took second place (34%). All the Alternaria isolates belonged to Section Alternaria with A. tenuissima as the predominant species-group. Alternariol was synthesised by 75% of the isolates, while both alternariol monomethyl-ether and tenuazonic acid by 76%. From the 100 I apples, 93 were contaminated with at least one of these mycotoxins. Alternaria was the main causal agent of MC in Argentinean Red Delicious apples, and fruit affected by this disease might be incorporated into the process line, with a consequent risk of mycotoxin contamination in apple by-products.


Asunto(s)
Alternaria/aislamiento & purificación , Manipulación de Alimentos , Malus/microbiología , Micotoxinas/metabolismo , Enfermedades de las Plantas/microbiología , Alternaria/clasificación , Alternaria/metabolismo , Argentina , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Frutas/microbiología , Hongos/clasificación , Hongos/aislamiento & purificación
20.
Int J Food Microbiol ; 322: 108585, 2020 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-32179333

RESUMEN

A total of 20 dried date samples, chosen as representative among those available on the Perugia (Umbria, Central Italy) market, were analyzed for the possible occurrence of fungal species and related contamination by fungal secondary metabolites. Twenty-six isolates, representative of the total mycobiota, were obtained and morphologically identified as belonging to the genera Aspergillus, Penicillium and Cladosporium. Inside each genus, molecular characterization (by partial sequencing of ITS region and/or ß-tubulin and calmodulin regions for Aspergillus and Penicillium isolates or actin region for Cladosporium isolates) and in vitro mycotoxigenic profile characterization (by LC-MS/MS analysis) showed the presence of the following species: A. flavus, A. tubingensis, P. brevicompactum, P. chrysogenum, P. crustosum, P. glabrum, P. solitum, P. venetum, C. cladosporioides, C. limoniforme and C. halotolerans, with A. tubingensis as the prevalent species and P. crustosum, P. solitum, P. venetum and C. limoniforme first reported here on dates. Date packaging and format showed an effect on the incidence of isolated fungi, with the lowest incidence recovered from whole dates and in hermetic bag packaging. These findings can be useful both for dried dates producers and consumers, guiding them towards choices of packaging and format with a lower risk of mycotoxigenic species presence. However, no fungal metabolites were detected in the dried date samples analyzed, which were therefore regarded as safe for human consumption, underlining the absence of correspondence between fungal isolation and mycotoxin contaminations.


Asunto(s)
Microbiología de Alimentos , Alimentos en Conserva/microbiología , Hongos/aislamiento & purificación , Phoeniceae/microbiología , Aspergillus/clasificación , Aspergillus/genética , Aspergillus/aislamiento & purificación , Aspergillus/metabolismo , Cladosporium/clasificación , Cladosporium/genética , Cladosporium/aislamiento & purificación , Cladosporium/metabolismo , Embalaje de Alimentos/métodos , Frutas/microbiología , Hongos/clasificación , Hongos/genética , Hongos/metabolismo , Humanos , Italia , Micotoxinas/análisis , Penicillium/clasificación , Penicillium/genética , Penicillium/aislamiento & purificación , Penicillium/metabolismo
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