scholarly journals Use of phosphites in postharvest to control anthracnose of yellow passionfruit

2019 ◽  
Vol 35 (6) ◽  
Author(s):  
Jaqueline Barbosa Dutra ◽  
Luiz Eduardo Bassay Blum
Keyword(s):  
Titratable Acidity ◽  
Soluble Solids ◽  
Alternative Methods ◽  
Postharvest Diseases ◽  
Passiflora Edulis ◽  
Physico Chemical ◽  
Colletotrichum Spp ◽  
Production Problems

Brazil is the largest producer of yellow passionfruit (Passiflora edulis f. flavicarpa) and one of its production problems is the anthracnose (Colletotrichum spp.). The use of fungicides on control of postharvest diseases is a method that protects the fruits during storage. However, precautions must be taken due to fungicide toxicity. The restriction to the use of fungicides in post-harvest led a demand for alternative methods of disease control, and, the phosphite application is one of these methods. Therefore, this work aimed to evaluate the effects of fruit immersion in phosphite on postharvest control of anthracnose. Two tests were developed in vitro to assess the effect on the fungus: phosphite Mg2 (40%P2O5+6%Mg), Zn (40%P2O5+10%Zn), Ca1 (30%P2O5+7%Ca) and K1 (40%P2O5+20%K2O). For the in vivo tests, passionfruit (Gigante Amarelo), were wounded and inoculated (50mL; 106conidia mL-1). Two tests were done with: Cu (25%P2O5+5%Cu), 2.5mL L-1; Zn, 2.5mL L-1; K1, 2.5mL L-1; Mg1 (30%P2O5+4%Mg), 3mL L-1; Ca1, 3mL L-1; Ca2 (10%P2O5+6%Ca), 4mL L-1; K2 (40%P2O5+20%K2O), 1.5mL L-1; Mg2 (40%P2O5+6%Mg), 1.5mL L-1; K3 (20%P2O5+20%K2O) 1.75 mL L-1; K4 (30%P2O5+20%K2O), 1.75mL L-1. Other two tests with phosphites Mg2, Ca1, Zn and K1 were with CaCl2 (2%) was developed. In addition, phosphites were tested at 25, 50, 100 and 200% of the dose: K2 (100%; 1.5mL L-1) and Ca1 (100%; 3 mL L-1). The phosphites Mg2, Ca1, K1 and Zn in vitro have reduced mycelial growth and fungus conidia production. The phosphites K1, K2, Ca1 and Zn were the ones that most reduced the size of the anthracnose lesion. There were no differences among treatments, concerning the physico-chemical fruit properties analyzed (% fresh mass loss, total soluble solids, pH and titratable acidity).

scholarly journals Application of Rosemary and Eucalyptus Essential Oils and Their Main Component on the Preservation of Apple and Pear Fruits

Horticulturae ◽  
2021 ◽  
Vol 7 (11) ◽  
pp. 479
Author(s):  
Panayiota Xylia ◽  
Antonios Chrysargyris ◽  
Zienab F. R. Ahmed ◽  
Nikolaos Tzortzakis
Keyword(s):  
Lipid Peroxidation ◽  
Natural Products ◽  
Essential Oils ◽  
Colony Growth ◽  
Soluble Solids ◽  
Penicillium Expansum ◽  
Postharvest Diseases ◽  
Main Component

Nowadays, increase fruit losses are being reported due to the development of fungal postharvest diseases. In an attempt to reduce the use of synthetic fungicides, a turn towards natural products such as essential oils (EOs) and natural compounds has been made. The objective of this study was to investigate the effects of eucalyptus (Euc), rosemary (Ros) EO, their mixture (50:50 v/v) and their common main component (i.e., eucalyptol) on the quality parameters, fruit response and inhibition of blue rot (Penicillium expansum) in apple and pear fruits during their shelf life. The results of the present study revealed that fungal colony growth decreased in vitro with exposure at eucalyptus EO (Euc-300 μL/L), rosemary EO (Ros-300 μL/L) and their mixture (Euc + Ros 100 and 300 μL/L). The exposure at Ros-100 μL/L stimulated spore production, whilst Euc + Ros (100 and 300 μL/L) and eucalyptol (100 and 300 μL/L) decreased spore germination. Moreover, the in vivo applied treatments resulted in decreased lesion growth of P. expansum in apple and pear fruits. Respiration rate increased with the application of Euc + Ros at 300 μL/L and eucalyptus EO (Euc-100 μL/L and Euc-300 μL/L) for both assessed fruits. On the other hand, no significant differences were reported on apples and pears total soluble solids and acidity values. The application of Euc + Ros-300 μL/L in apples increased hydrogen peroxide (H2O2) levels, whilst Euc-100 and Euc-300 μL/L increased lipid peroxidation levels. Regarding pear fruits, exposure to Euc-100 μL/L and Ros-100 μL/L resulted in increased H2O2 whereas, Euc-100 μL/L, Ros- (100 and 300 μL/L) and eucalyptol (100 and 300 μL/L) also increased lipid peroxidation. The findings of this study indicate that the investigated natural products can be explored for the preservation of fresh apples and pears, as alternative natural fungicides with consideration of the fresh produce quality attributes.

scholarly journals Effect of Alcoholic Extracts of Cymbopogon citratus upon the Control of Colletotrichum gloeosporioides in vitro and upon the Post-harvest Quality of Guavas

2019 ◽  
pp. 1-8
Author(s):  
Ana P. F. A. Santos ◽  
Amanda P. Mattos ◽  
Adriana T. Itako ◽  
João B. Tolentino Júnior ◽  
Gabriela S. Moura ◽  
...  
Keyword(s):  
Colletotrichum Gloeosporioides ◽  
Titratable Acidity ◽  
Physicochemical Characteristics ◽  
Soluble Solids ◽  
Post Harvest ◽  
Methanolic Extracts ◽  
Dose Dependent

Aims: This work aimed at evaluating the effects of ethanolic and methanolic extracts of lemongrass upon the control in vitro of Colletotrichum gloeosporioides and upon the post-harvest quality of guavas “Paluma”. Methodology: We analyzed the inhibition of mycelial growth and sporulation of the pathogen at different concentrations of the extracts (8%; 5%; 3%; 1.5% and 0.5%). In the post-harvest assay, the guavas were treated by immersion in distilled water, ethanolic and methanolic extracts (1%; 0.5% and 0.25%) and stored at 25ºC ± 2ºC for eight days. We evaluated mass loss, total soluble solids, total titratable acidity, ratio, reducing and non-reducing sugars, ascorbic acid and pH and the incidence of anthracnose. Results: In the test in vitro, the pathogen growth inhibition was dose-dependent and the sporulation was completely inhibited upon higher concentrations of extract. At post-harvest, the fruits maintained their physicochemical characteristics, and the treatments were not efficient at retarding fruit ripening. Although the tested treatments inhibited the plant pathogen C. gloesporioides in vitro, they were not efficient at controlling the disease in vivo. Conclusion: The extracts showed control in vitro of C. gloeosporioides at 8%. However, the extracts were not effective at controlling the disease after harvest.

scholarly journals (E)-2-Hexenal Can Stimulate Botrytis cinerea Growth in vitro and on Strawberries in vivo during Storage

1998 ◽  
Vol 123 (5) ◽  
pp. 875-881 ◽  
Author(s):  
Elazar Fallik ◽  
Douglas D. Archbold ◽  
Thomas R. Hamilton-Kemp ◽  
Ann M. Clements ◽  
Randy W. Collins ◽  
...  
Keyword(s):  
Botrytis Cinerea ◽  
Spore Germination ◽  
Mode Of Action ◽  
Mycelial Growth ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
In Vivo Studies ◽  
High Concentration

Some plant-derived natural volatile compounds exhibit antifungal properties and may offer an opportunity to control the causes of postharvest spoilage without affecting quality of, or leaving a residue on, fresh produce. The natural wound volatile (E)-2-hexenal has exhibited significant antifungal activity in earlier studies, but effects on spore germination and mycelial growth have not been separated, nor has the inhibitory mode of action been determined. To determine the efficacy of (E)-2-hexenal for control of Botrytis cinerea Pers. ex Fr. spore germination and mycelial growth, and to examine the mode of action, in vitro and in vivo studies were performed. Under in vitro bioassay conditions, spore germination was more sensitive to the compound than was mycelial growth. Vapor from 10.3 μmol of (E)-2-hexenal in a 120-mL petri dish completely inhibited spore germination. However, 85.6 μmol of (E)-2-hexenal was required to completely inhibit mycelial growth. Lower concentrations of the compound (5.4 and 10.3 μmol) significantly stimulated mycelial growth, especially when the volatile was added 2 days following inoculation. Mycelial growth did not occur as long as the vapor-phase concentration was 0.48 μmol·L-1 or greater. Light microscopy analysis indicated that a high concentration of volatile compound dehydrated fungal hyphae and disrupted their cell walls and membranes. Exposure of B. cinerea-inoculated and non-inoculated strawberry (Fragaria ×ananassa Duch.) fruit in 1.1-L low-density polyethylene film-wrapped containers to vapor of (E)-2-hexenal at 85.6 or 856 μmol (10 or 100 mL, respectively) per container for durations of 1, 4, or 7 days during 7 days of storage at 2 °C promoted the incidence of B. cinerea during subsequent shelf storage at 20 to 22 °C. Loss of fruit fresh mass and fruit firmness during storage at 22 °C was increased by (E)-2-hexenal treatment, but fruit total soluble solids, pH, titratable acidity, and color (L, C, and H values) were not affected. Thus, maintenance of a high vapor-phasel level of (E)-hexenal, perhaps >0.48 μmol·L-1, may be necessary to inhibit mycelial growth and avoid enhancing postharvest mold problems, while significantly higher levels may be necessary to completely eliminate the pathogen.

scholarly journals 411 Elevated Oxygen Atmospheres as a Decay Control Alternative on Strawberry

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 514F-515 ◽  
Author(s):  
Annette L. Wszelaki ◽  
Elizabeth J. Mitcham
Keyword(s):  
Atmospheric Oxygen ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Postharvest Disease ◽  
Low Oxygen ◽  
Oxygen Levels ◽  
Off Flavors ◽  
Fruit Flavor

Controlled atmospheres have been proven an effective postharvest disease deterrent for strawberries both in transport and storage. However, these treatments do not provide residual protection once the commodity is removed from the atmosphere, and the atmospheres can cause off-flavors in the fruit. Elevated oxygen atmospheres are a novel addition to this technology and could potentially provide better decay control without the harmful effects on fruit flavor aspects. Elevated oxygen will potentially discourage microbial growth, as anaerobes grow best under very low oxygen levels and aerobes grow best under atmospheric oxygen. Threshold elevated oxygen levels to prevent Botrytis cinerea growth in vitro and in vivo on strawberry were assessed. Botrytis cultures (mycelial plugs and spores) and fresh strawberry fruit were exposed to 21%, 40%, 60%, and 80% oxygen atmospheres at 5 °C for 5, 7, and 14 d. Growth of cultures from mycelial plugs was evaluated after treatment and during post-treatment incubation by measuring the diameter of the fungus. Spore germination and germ tube elongation were evaluated every 24 h for 3 days after treatment by counting the number of germinated spores and measuring elongation, respectively. Strawberry quality including firmness, color, soluble solids, titratable acidity, ethylene production and respiration rates, and presence of defects were evaluated upon removal from the elevated oxygen atmospheres as well as after 1, 3, and 5 d storage in air at 20 °C simulating market conditions.

scholarly journals Acibenzolar-S-methyl against Botrytis mold on table grapes in vitro and in vivo

2019 ◽  
Vol 5 (1) ◽  
pp. 52 ◽  
Author(s):  
Khamis Youssef ◽  
Sergio Roberto ◽  
Ronan Colombo ◽  
Marcelo Canteri ◽  
Kamel Elsalam
Keyword(s):  
Mycelial Growth ◽  
Titratable Acidity ◽  
Gray Mold ◽  
Soluble Solids ◽  
Table Grapes ◽  
Significant Difference ◽  
Randomized Experimental Design ◽  
Set Up

The objective of this work was to investigate the effect of the resistance inducer Acibenzolar-S-methyl (ASM), against Botrytis mold on table grapes in vitro and in vivo. To assess the effect of ASM on mycelial growth Botrytis cinerea, different concentrations (0.125, 0.25, 0.5, 1.0, 2.0 and 3% w:v) were tested. Treatments were set up in triplicate, in a completely randomized experimental design, and replicated twice. Results were expressed in minimum inhibitory concentrations and effective dose per 50% response of mycelial growth. Healthy table grapes (cvs. Italia and Benitaka) were harvested at full ripe to evaluate the ASM 1% effect against gray mold under artificial conditions. Bunches were split into two groups in order to perform two types of experiments (spray or immersion). For both trials, treated bunches were arranged in carton boxes and stored at 2±1 °C, for one month, followed by one week of shelf-life at 22±2 °C. In order to evaluate the ASM effect against gray mold under field conditions, ASM 1% was sprayed on both cultivars one week before harvest. Grapes treated with iprodione 0.2% with three applications during the season were included as a standard chemical control. Bunches were harvested at full ripe, arranged in carton boxes and submitted to a cold storage process as described previously. Results for the in vitro experiments showed that the minimum inhibitory concentration of ASM was achieved by 3% and the ED50 was 0.04%. Under artificial conditions, for both cultivars, the efficacy of ASM was higher when the grapes were immersed than sprayed. A significant difference was observed for ASM as compared with control. Regarding the effect of ASM against gray mold in the field, the incidence of gray mold was recorded for both cultivars. For ‘Italia’ and ‘Benitaka’ grapes, ASM, iprodione and sulfur dioxide pad reduced the incidence of gray mold by 85, 79 and 77%, and by 80.5, 73 and 82%, respectively. As for the physico-chemical berry properties, none of the treatments were significantly different from the control for total soluble solids, titratable acidity and color index. A single ASM treatment applied one week before harvest is effective for controlling gray mold in ‘Italia’ and ‘Benitaka’ table grapes.

THYROID STIMULATORS AND THYROID STIMULATION

1971 ◽  
Vol 66 (3) ◽  
pp. 558-576 ◽  
Author(s):  
Gerald Burke
Keyword(s):  
Regulatory System ◽  
Control Site ◽  
Thyroid Cell ◽  
Primary Control ◽  
Physico Chemical ◽  
Site Of Action ◽  
Long Acting

ABSTRACT A long-acting thyroid stimulator (LATS), distinct from pituitary thyrotrophin (TSH), is found in the serum of some patients with Graves' disease. Despite the marked physico-chemical and immunologic differences between the two stimulators, both in vivo and in vitro studies indicate that LATS and TSH act on the same thyroidal site(s) and that such stimulation does not require penetration of the thyroid cell. Although resorption of colloid and secretion of thyroid hormone are early responses to both TSH and LATS, available evidence reveals no basic metabolic pathway which must be activated by these hormones in order for iodination reactions to occur. Cyclic 3′, 5′-AMP appears to mediate TSH and LATS effects on iodination reactions but the role of this compound in activating thyroidal intermediary metabolism is less clear. Based on the evidence reviewed herein, it is suggested that the primary site of action of thyroid stimulators is at the cell membrane and that beyond the(se) primary control site(s), there exists a multifaceted regulatory system for thyroid hormonogenesis and cell growth.

A Study on UV Filter Chemicals from Annex VII of European Union Directive 76/768/EEC, in the In Vitro 3T3 NRU Phototoxicity Test

1998 ◽  
Vol 26 (5) ◽  
pp. 679-708 ◽  
Author(s):  
Horst Spielmann ◽  
Michael Balls ◽  
Jack Dupuis ◽  
Wolfgang J. W. Pape ◽  
Odile de Silva ◽  
...  
Keyword(s):  
Neutral Red ◽  
Optimum Concentration ◽  
Alternative Methods ◽  
Uv Filter ◽  
Eu Directive ◽  
Optimum Concentration Range ◽  
The Impact ◽  
Positive Results

In 1996, the Scientific Committee on Cosmetology of DGXXIV of the European Commission asked the European Centre for the Validation of Alternative Methods to test eight UV filter chemicals from the 1995 edition of Annex VII of Directive 76/768/EEC in a blind trial in the in vitro 3T3 cell neutral red uptake phototoxicity (3T3 NRU PT) test, which had been scientifically validated between 1992 and 1996. Since all the UV filter chemicals on the positive list of EU Directive 76/768/EEC have been shown not to be phototoxic in vivo in humans under use conditions, only negative effects would be expected in the 3T3 NRU PT test. To balance the number of positive and negative chemicals, ten phototoxic and ten non-phototoxic chemicals were tested under blind conditions in four laboratories. Moreover, to assess the optimum concentration range for testing, information was provided on appropriate solvents and on the solubility of the coded chemicals. In this study, the phototoxic potential of test chemicals was evaluated in a prediction model in which either the Photoirritation Factor (PIF) or the Mean Photo Effect (MPE) were determined. The results obtained with both PIF and MPE were highly reproducible in the four laboratories, and the correlation between in vitro and in vivo data was almost perfect. All the phototoxic test chemicals provided a positive result at concentrations of 1μg/ml, while nine of the ten non-phototoxic chemicals gave clear negative results, even at the highest test concentrations. One of the UV filter chemicals gave positive results in three of the four laboratories only at concentrations greater than 100μg/ml; the other laboratory correctly identified all 20 of the test chemicals. An analysis of the impact that exposure concentrations had on the performance of the test revealed that the optimum concentration range in the 3T3 NRU PT test for determining the phototoxic potential of chemicals is between 0.1μg/ml and 10μg/ml, and that false positive results can be obtained at concentrations greater than 100μg/ml. Therefore, the positive results obtained with some of the UV filter chemicals only at concentrations greater than 100μg/ml do not indicate a phototoxic potential in vivo. When this information was taken into account during calculation of the overall predictivity of the 3T3 NRU PT test in the present study, an almost perfect correlation of in vitro versus in vivo results was obtained (between 95% and 100%), when either PIF or MPE were used to predict the phototoxic potential. The management team and participants therefore conclude that the 3T3 NRU PT test is a valid test for correctly assessing the phototoxic potential of UV filter chemicals, if the defined concentration limits are taken into account.

scholarly journals Physicochemical Characterization and Functional Potential of Phaseolus vulgaris L. and Phaseolus coccineus L. Landrace Green Beans

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 803
Author(s):  
Elia Nora Aquino-Bolaños ◽  
Alma Karina Garzón-García ◽  
Jimena Esther Alba-Jiménez ◽  
José Luis Chávez-Servia ◽  
Araceli Minerva Vera-Guzmán ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Physicochemical Characterization ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Total Phenolic ◽  
Green Beans ◽  
Total Sugars ◽  
Total Soluble Solids ◽  
Color Parameters

The green bean is an important crop worldwide, because it is rich in protein, dietary fiber, vitamins, and minerals, as well as bioactive compounds that provide it with important functional properties; however, the composition of many landraces is still unknown. The purpose of this project was to characterize Phaselus vulgaris and coccineus L. landrace green beans on pH, titratable acidity, total soluble solids, total sugars, color parameters, total phenols, monomeric anthocyanins, and in vitro antioxidant activity (DPPH and FRAP). Regarding the content of total sugars, differences were registered between both species, as opposed to results observed in total soluble solids. Color parameters showed higher reddish tones for P. vulgaris landraces, though P. coccineus had a higher total phenolic content, especially the reddish landraces, which correlated directly to a higher antioxidant activity by DPPH and FRAP. In the protein content, the species P. vulgaris registered the highest content. These results could contribute to a greater use and even promote the genetic improvement of the outstanding pods that serve as one of the main food products in rural regions for higher benefits.

scholarly journals Efficacy of coupling gamma irradiation with calcium chloride and lemongrass oil in maintaining guava fruit quality and inhibiting fungal growth during cold storage

2018 ◽  
Vol 30 (1) ◽  
pp. 67-78 ◽  
Author(s):  
Ramadan A. Hassanein ◽  
Ehab A. Salem ◽  
Ahmed A. Zahran
Keyword(s):  
Vitamin C ◽  
Fruit Quality ◽  
Cold Storage ◽  
Fungal Growth ◽  
Alternaria Solani ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Γ Irradiation ◽  
Lemongrass Oil

AbstractThis study was performed to explore the efficacy of combining more than one postharvest treatment in maintaining some quality attributes and reducing fungal pathogenicity in cold-stored guava fruits. The investigated postharvest treatments included the control, CaCl2(4%), lemongrass oil (2 dm3kg−1), gamma (γ) irradiation (0.2, 0.4 and 0.6 kGy), 0.4 kGy γ irradiation + CaCl2(4%), and 0.4 kGy γ irradiation + lemongrass oil (2 dm3kg−1). The studied physiochemical attributes included weight loss, decay percentage, fruit firmness, total soluble solids (TSS), titratable acidity (TA), and vitamin C content. Different fungal species were also isolated from decayed fruits and were identified asAlternaria alternata,Alternaria solani,Aspergillus niger,Botrytis cinerea,Fusarium solaniandRhizopus stolonifer. The severity of infection for the different fungi was determined, and anin vitroantifungal assay was conducted for lemongrass oil. All the investigated treatments generally reduced decay and water loss percentages, and controlled TSS, TA and vitamin C decrements that occurred during cold storage. On the other hand, higher irradiation doses generally increased fruit softness, and the 0.4 kGy γ dose did not contribute to the overall fruit quality when coupled with CaCl2and lemongrass oil, compared to CaCl2and lemongrass oil treatments alone.

scholarly journals Assessment of the efficiency of essential oils in the preservation of postharvest papaya in an antimicrobial packaging system

2012 ◽  
Vol 15 (4) ◽  
pp. 333-342 ◽  
Author(s):  
Paula Judith Perez Espitia ◽  
Nilda de Fátima Ferreira Soares ◽  
Laura Costa Moreira Botti ◽  
Nathália Ramos de Melo ◽  
Olinto Liparini Pereira ◽  
...  
Keyword(s):  
Essential Oils ◽  
Physicochemical Parameters ◽  
Phytopathogenic Fungi ◽  
Soluble Solids ◽  
Postharvest Diseases ◽  
Packaging System ◽  
Antimicrobial Packaging ◽  
Post Harvest ◽  
Lemon Grass

Rot and damage caused by post-harvest phytopathogenic fungi affect fruit quality. Essential oils (EO) are considered as an alternative to fungicides. Postharvest diseases of fruits may also be controlled by the bagging approach and the use of antimicrobial packaging. Based on the beneficial properties of EO and the concepts of bagging and antimicrobial packaging, this study aimed to develop sachets containing EO to be used as part of an antimicrobial packaging system. The activities of oregano, cinnamon and lemon grass EO were evaluated testing the sachets in vitro against the phytopathogenic fungi Alternaria alternata, Fusarium semitectum, Lasiodiplodia theobromae and Rhizopus stolonifer. The effects of the sachets on the microbiological and physicochemical parameters of post-harvest papaya were also evaluated. Both pure and sachet-incorporated EO showed antifungal activity in vitro against all tested fungi. For papaya, sachets containing cinnamon, oregano and lemon grass showed a significant reduction in the growth of mesophilic aerobic bacteria, yeasts and mould, with the cinnamon sachet causing the greatest reduction in microorganisms at the end of the storage time. Physicochemical parameters of papaya, such as weight loss, colour, firmness, total soluble solids/titratable acidity ratio and pH were not significantly altered by the presence of EO sachets, thus not affecting the natural ripening process of the papaya.

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