Postharvest Control Of Anthracnose Research Articles

Bacillus subtilis and Trichoderma harzianum on the quality and occurrence of anthracnose in bananas

The objective of this study was to assess the efficiency of Trichoderma harzianum and Bacillus subtilis on postharvest control of anthracnose, the effects on postharvest quality in ‘Nanicão’ bananas, and the sensory acceptance of fruits. In vitro and in vivo tests were performed. The in vitro tests included the following treatments: control (distilled water), T. harzianum, B. subtilis, and thiabendazole. In vitro tests consisted of pairing Colletotrichum musae with T. harzianum and B. subtilis by daily measuring the mycelial growth of C. musae and by counting the spore germination of C. musae. For in vivo tests, the treatments were control (distilled water), T. harzianum, B. subtilis, T. harzianum + B. subtilis, and thiabendazole. In vivo tests consisted of a daily evaluation of the incidence and severity of anthracnose in ‘Nanicão’ bananas. Some physicochemical characteristics of fruits were evaluated (weight loss, color, pulp firmness, soluble solids (SS), titratable acidity (TA), pH, and SS/TA ratio), as well as the sensory acceptance of bananas. Based on the results, the application of T. harzianum in ‘Nanicão’ bananas was efficient in decreasing the severity of anthracnose caused by C. musae, but treatments with biological control agents were inefficient in this process. On postharvest quality, treatments with biological control agents seem to have accelerated the maturation process. However, results from the sensory analysis showed that fruit acceptance was not affected.

Postharvest control of anthracnose in avocado with cassava starch and corn starch films

The objective of this study was to evaluate the effect of cassava starch and corn starch films on the control of anthracnose in avocado. The fruits were inoculated with conidia suspension and were then immersed in solutions with cassava starch and corn starch alone or in combination at concentrations of 1, 2, 3 and 4% under curative and preventive methods. The variables analysed included mean damaged area, area under the disease progress curve (AUDPC) and fruit fresh weight. Under the curative method, the mean damaged area and AUDPC were reduced in fruits treated with 1% and 4% cassava starch and 1% corn starch. Under the preventive method, fruits treated with 2% cassava starch or 2% corn starch alone resulted in reduced mean damaged area and AUDPC. The combinations of cassava starch and corn starch at 2, 3, and 4% were effective in reducing the mean damaged area and AUDPC under curative control. Under the preventive method, the combinations of cassava starch and corn starch at 2 and 3% reduced the AUDPC, and the mean damaged area was decreased with both starches at 3%. Scanning electron microscopy images revealed a layer of protective film on the fruit's surface that probably prevented the pathogen from penetrating. In addition, there was deformation of hyphae promoted by the action of the films.

Integrated application of transcriptomics and metabolomics provides insights into the antifungal activity of α-phenylcinnamic acid against Colletotrichum gloeosporioides

Anthracnose caused by Colletotrichum gloeosporioides leads to significant economic loss of varieties of tropical and subtropical fruit. In the present study, a cinnamic acid derivative α-phenylcinnamic acid (α-PA) was found effective in control of postharvest anthracnose on mango fruit. α-PA strongly inhibited conidia germination, germ tube elongation, and appressorium formation. To elucidate the underlying molecular mechanisms by which α-PA shows antifungal activity, a transcriptomics and a widely targeted metabolomics analysis were conducted to study the changes in gene expression and metabolic profile. The result showed that the expression of 1477 genes and content of 198 metabolites were changed by α-PA. The following KEGG enrichment and correlation analysis suggested that biosynthesis of amino acids and some secondary metabolites were interfered by α-PA, including indoles which are one group of melanin precursors. In addition, qRT-PCR analysis and measurement of melanin revealed that α-PA down-regulated the expression of melanin biosynthesis genes and reduced melanin biosynthesis. Taken together, these data suggest that α-PA could decrease anthracnose in postharvest fruit by interfere with amino acid and secondary metabolite metabolism of C. gloeosporioides.

Use of phosphites in postharvest to control anthracnose of yellow passionfruit

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).

Development, characterisation and efficacy evaluation of biochemical fungicidal formulations for postharvest control of anthracnose (Colletotrichum gloeosporioides Penz) disease in mango

The objectives of the study are to develop and characterise formulations with volatile molecules in an emulsifiable concentrate form, for their antimicrobial properties and to evaluate their efficacies against Colletotrichum gloeosporioides Penz., to control anthracnose in mangoes after harvest. Results showed EC39 and EC40 among formulations were characterised for their excellent emulsification properties, the droplet size of 192.34 ± 0.48 nm and 227.4 ± 0.71 nm and Zeta potential of −52.5 ± 2.76 mv and −48.84 ± 2.62 mv, respectively, with better storage stability at 10 ± 20 °C and RH 80 ± 5%. In vitro assay, 100% inhibition of visual spore germination by 0.15% and 0.2% MIC value for EC39 and EC40, respectively Studies on the efficacy of their fungicide properties also indicated the IC50 value of 0.161% and 0.162% for EC39 and EC40 respectively for mycelial growth inhibition. In vivo testing too, EC39 and EC40 effectively controlled anthracnose incidence in mango in a dosage-dependent manner.

Postharvest control of anthracnose in mangoes by fumigation with vinegar and ethanol vapours

Anthracnose disease of mangoes is caused by Collectotrichum gloeosporioides. A control method that does not include synthetic fungicides would be beneficial therefore fumigation, in an especially designed vapour exposure box, with vapour from upland rice vinegar and ethanol were tested in vitro on C. gloeosporioides isolated from mangoes and cultured on PDA. Fumigation times were 0, 5, 6, 7, 8, 9 or 10 min for ethanol and vinegar vapours separately and in mixtures at different ratios for 0, 10, 11, 12, 13, 14 or 15 min. Exposure to either ethanol vapour or vinegar vapour controlled both mycelial growth and conidia germination during subsequent storage for seven days at 28°C-32°C, but ethanol was more effective than vinegar and ethanol was more effective alone than in any of the combinations with vinegar. These results provide a successful organic anthracnose control method, but in vivo testing is recommended before commercial application.

Postharvest control of anthracnose in mangoes by fumigation with vinegar and ethanol vapours

Postharvest control of anthracnose in mangoes by fumigation with vinegar and ethanol vapours

Ethanol on the postharvest control of anthracnose in ‘Kumagai’ guava

ABSTRACT The aim of this study was to evaluate the effects of ethanol on the control of Colletotrichum spp. in ‘Kumagai’ guava and on the fruit physical-chemical attributes. For this purpose, three assays were carried out. For the first assay, fruit were exposed to ethanol vapor (0, 1, 2, 4, and 8 mL∙kg-1), applied in hermetic containers. On the second, ethanol was applied by immersion for 2 minutes in different concentrations (20, 30, 40, and 50%). On the last assay, fruit were immersed in 30, 40, and 50% ethanol for 2, 5, and 10 minutes. Fruit that were not exposed to volatile (first assay) or water treated (second and third assay) were used as control. In all assays, guavas were first inoculated with a conidial suspension of Colletotrichum spp. and after 2 hours, fruit were subject to ethanol. Fruit were stored at 25 °C / 80% RH for 8 days and assessed for incidence, rot severity and physical-chemical properties. Conidial germination and mycelial growth of Colletotrichum spp. were evaluated on in vitro assays. It was observed that 40 and 50% of ethanol, applied by fruit immersion for 2 min, reduced incidence and anthracnose severity with no changes in the guava physical-chemical attributes, when fruit were stored at 25 °C. Applied as a vapor, ethanol reduced only the incidence, but did not reduce anthracnose severity in guavas stored at 25 °C. Under cold storage, fruit treated with 40% ethanol exhibited a reduction of 19% in anthracnose severity. In vitro, ethanol vapor at 70 and 140 µL∙L-1 inhibited Colletotrichum spp. mycelial growth rate and when incorporated in potato-dextrose-agar, ethanol (30, 40 and 50%) inhibited Colletotrichum spp. mycelial growth rate and conidial germination.

Cassava starch coatings for postharvest control of papaya anthracnose

The effects of coating papaya fruit ( Carica papaya ) with cassava starch were studied, to determine the best concentration and mode of action of this material in postharvest control of anthracnose. The concentrations of starch tested were 1%, 2%, 3% and 4%. These were prepared to give gel consistency. Surface sterilized papaya fruits were inoculated with conidia of Colletotrichum gloeosporioides and incubated for 48 h in a moisture chamber. The were then treated with cassava fruit gels and dried. During the following 14 d storage period, fruit maturation and anthracnose on the fruits were assessed, and electron microscopy was used to examine fruit epicarps. All cassava starch coating concentrations reduced fruit maturation and anthracnose, with the 2%, 3% or 4% coatings giving 100% disease control. The 2% starch coating is likely to be optimum, considering the lower cost efficiency of disease control. The mechanism of disease control provided by the coating is likely to be related to delay of ripening and the formation of a protective layer over the fruit.

Exogenous nitric oxide‐induced postharvest disease resistance in citrus fruit to Colletotrichum gloeosporioides

Nitric oxide (NO) is an important signaling molecule involved in numerous plant responses to biotic and abiotic stresses. To investigate the effects of NO on the control of postharvest anthracnose caused by Colletotrichum gloeosporioides in citrus fruit and its possible mechanisms, citrus fruit were treated with an NO donor. The results showed that exogenous NO released from 50 µmol L(-1) sodium nitroprusside aqueous solution could effectively reduce the disease incidence and lesion diameter of citrus fruit inoculated with C. gloeosporioides during storage at 20 °C. Exogenous NO could regulate hydrogen peroxide levels, stimulate the synthesis of phenolic compounds, and induce phenylalanine ammonia-lyase, peroxidase, polyphenol oxidase, catalase activities, and the ascorbate-glutathione cycle. Furthermore, exogenous NO could inhibit weight loss, improve the ascorbic acid and titratable acidity content, and delay the increase in total soluble solids content in citrus fruit during storage at 20 °C. The results suggest that the use of exogenous NO is a potential method for inducing the disease resistance of fruit to fungal pathogens and for extending the postharvest life of citrus fruit.

Effect of propolis on postharvest control of anthracnose and quality parameters of ‘Kent’ mango

The objective of this study was to evaluate the efficacy of propolis treatment for reducing anthracnose development on mango fruit of variety Kent; and compare its efficacy to chitosan treatment, which is already a well-studied natural produce. For in vitro experiments, Petri plates were amended with (0, 0.5, 1.0, 1.5, 2.0 and 2.5% v/v) propolis or (0, 0.25, 0.5, 1.0, 1.5 and 2.0% w/v) chitosan solutions. For the in vivo experiments, mangoes were infected with a spore suspension of Colletotrichum gloeosporioides and solution of either propolis (1.5%) or chitosan (1.5%) were used for controlling the pathogen development. The fruits were stored for 14 days at 12±1°C and 83±2% RH, and then, for another 7 days at 23°C, 82%. Lesion area, firmness, chemical composition, as well as color of the skin were used for evaluating and compare the performance of the two products. Even if the in vitro results demonstrated the net superiority of propolis for controlling the development of the pathogen, the in vitro results showed the opposite order when classifying the performance of the products with alive fresh produce. The results obtained suggested that propolis, as well as chitosan, may be used as treatment for controlling anthracnose, maintaining quality, and increasing the shelf life in ‘Kent’ mango. However, propolis was far from producing competitive results to chitosan treatment performance.

Efeito do óleo de soja no controle da antracnose e na conservação da manga cv. Palmer em pós-colheita

Na fase de pós-colheita da manga, a antracnose (Colletotrichum gloeosporioides Penz.) é a doença mais importante em termos de expressão econômica. Seu controle vem sendo feito pela imersão dos frutos por 5 minutos, em água a 55 ºC, acrescida de thiabendazo1 a 0,2%. Embora seja eficaz no controle dessa doença, esse fungicida pode deixar resíduo, o que não satisfaz os consumidores que vêm, a cada ano, aumentando as suas exigências por frutos livres de resíduos de agroquímicos e ambientalmente corretos. Dessa forma, esses experimentos foram conduzidos visando à seleção de produtos biológicos que tenham potencial para o controle da antracnose e para a conservação da manga na pós-colheita. Os frutos, colhidos no estádio de maturação 3 e 4, foram imersos por 5 minutos em thiabendazol a 0,24% e benomil a 0,1 % a 22 ºC, 40 ºC ou 45 ºC e em diferentes concentrações de óleo de soja isolado ou em mistura com benomil, thiabendazol e com extrato etanólico de sucupira (Pterodon pubescens Benth.). Após os tratamentos, os frutos foram mantidos em câmaras a 27 ± 1 ºC, 72 % a 85 % de UR (Experimento nº 1) e a 17ºC a 85% a 100% de UR (experimento nº 2). As avaliações foram efetuadas aos 15 dias (experimento nº 1 ) e aos 30 dias (experimento nº 2) após os tratamentos, determinando-se as porcentagens da superfície dos frutos cobertas com lesões, de frutos verdes, maduros e de vez, ºBrix e textura. O óleo de soja, isolado ou misturado com benomil ou thiabendazol, a 22 ºC ou a 40 ºC, aumentou o tempo de prateleira da manga Palmer e foi eficaz no controle da antracnose.

Studies on the effect of fruit-coating polymers and organic acids on growth of Colletotrichum musae in vitro and on post-harvest control of anthracnose of bananas

Twelve coating materials and their components which can be applied to fruit, and eight organic acids were incorporated into agar media to determine their ability to inhibit mycelial growth of Colletotrichum musae . Of the coating materials tested, two formulations based on a mixture of sucrose esters + fatty acids, Semperfresh F (SFS) and Semperfresh acid-stable (SFAS) at 0·1–1% concentrations were most effective at inhibiting mycelial growth of C. musae . The components used in fruit-coating materials which significantly inhibited growth were oleic, palmitic and lauric acids. Coating materials like chitosan, carboxymethyl cellulose and carboxymethyl chitosan were ineffective at concentrations up to 1%. The effect of organic acids and their salts on the growth of C. musae varied with concentration (1–3%). Malic, citric, oxalic and maleic acids all significantly ( P C. musae . Complete inhibition of growth was achieved with potassium sorbate and sodium benzoate at 0·125% and oxalic and maleic acids at 0·5% (w/v). Organic acids also increased the lag time prior to growth initiation. Coating materials, alone or in combination with organic acids or a fungicide (benomyl), were compared for their ability to inhibit post-harvest lesion expansion of anthracnose symptoms on banana fruits at 25 °C and 85–90% r.h. SFAS at 1·5 or 3%, and SFAS + 2% potassium sorbate were the most effective treatments when intact skin of banana fruits was inoculated with spores of C. musae prior to application. When fruits were wound-inoculated with mycelium of C. musae , combinations of 3% SFAS with benomyl (250 or 500 g l −1 ) controlled lesion expansion more effectively than the fungicide alone. SFAS alone, or with potassium sorbate, or sodium benzoate significantly ( P

Post-harvest control of anthracnose and stem-end rots of Fuerte avocados with prochloraz and other fungicides

Mature unripe Fuerte avocados from Alstonville (northern New South Wales) and Walkamin (northern Queensland) were dipped in fungicides immediately after harvest. In screening tests in which the fungicides were applied for 5 min, prochloraz [1 g active constituent (a.c.)/l] controlled anthracnose (Glomerella cingulata var. minor), a severe form of stem-end rot caused by Dothiorella aromatica and Botryodiplodia theobromae, and a mild form of stem-end rot caused by G. cingulata var. minor and Stilbella cinnabarina. Prochloraz increased the percentages of disease-free fruit from 1 to 90% at Alstonville and from 6 to 77% at Walkamin. Percentages of fruit with acceptable disease levels were similarly increased. Other fungicides were less effective in the screening experiments. CGA 6425 1 (0.2 g a.c./l) and carbendazim (1 g a.c./l) controlled both forms of stem-end rot, but not anthracnose. Guazatine (1 g a.c./l) controlled only the mild form of stem-end rot. In a second experiment with avocados from Alstonville, prochloraz was applied at 0.125, 0.25, 0.5, and 1.0 g a.c./l for 0.5, 1,2 and 4 min. Every treatment except 0.125 g a.c./l for 1 min controlled anthracnose and improved overall disease control. Prochloraz neither caused nor exacerbated several physiological disorders that developed during ripening in these investigations.