scholarly journals Effect of Marine Bacteria and Ulvan on the Activity of Antioxidant Defense Enzymes and the Bio-Protection of Papaya Fruit against Colletotrichum gloeosporioides

Antioxidants ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 580 ◽  
Author(s):  
Roberto G. Chiquito-Contreras ◽  
Bernardo Murillo-Amador ◽  
Saul Carmona-Hernandez ◽  
Cesar J. Chiquito-Contreras ◽  
Luis G. Hernandez-Montiel
Keyword(s):  
Enzyme Activity ◽  
Marine Bacteria ◽  
Antioxidant Defense ◽  
Colletotrichum Gloeosporioides ◽  
Disease Incidence ◽  
Defense Enzyme ◽  
Lesion Diameter ◽  
Antioxidant Defense Enzyme

Anthracnose, caused by Colletotrichum gloeosporioides, is one of the most important diseases in papaya fruit. Its control has been achieved with synthetic fungicides, but the application of marine bacteria and the sulphated polysaccharide ulvan (structural description: β[1,4]-D-GlcA-α[1,4]-L-Rha 3 sulfate, β[1,4]-L-IdoA-α[1,4]-L-Rha 3 sulfate, β[1,4]-D-Xyl-α[1,4]-L-Rha 3 sulfate, and β[1,4]-D-Xyl 2-sulfate-α[1,4]-L-Rha 3 sulfate) from Ulva sp. can be an alternative in the use of agrochemicals. Thus, the objective of this study was to assess the effect in vitro and in vivo of two marine bacteria, Stenotrophomonas rhizophila and Bacillus amyloliquefaciens, and ulvan in papaya fruit’s bio-protection against C. gloeosporioides. The capacity of marine bacteria to inhibit mycelial growth and phytopathogen spore germination in vitro through volatile organic compounds (VOCs) and carbohydrate competition was evaluated. Fruit was inoculated with bacteria, ulvan, and C. gloeosporioides and incubated at 25 °C and 90% of relative humidity (RH) for seven days. Disease incidence (%), lesion diameter (mm), and antioxidant defense enzyme activity (such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) were quantified. In vitro, C. gloeosporioides was inhibited by S. rhizophila and B. amyloliquefaciens. In vivo, disease incidence and the lesion diameter of anthracnose on papaya fruit were significantly reduced by marine bacteria and ulvan. Antioxidant defense enzyme activity played an important role in fruit bio-protection against C. gloeosporioides. The application of marine bacteria and ulvan can be an alternative in the sustainable postharvest management of papaya.

scholarly journals In vitro, In vivo and In situ, Effect of Mancozeb 80 WP on Colletotrichum gloeosporioides (Penz.) Penz. and Sacc., Causative Agent of Anthracnose of Cashew (Anacardium occidentale L.) in Chad and Cameroon

2021 ◽  
pp. 1-14
Author(s):  
Ngoh Dooh Jules Patrice ◽  
Deurnaye Placide ◽  
Abdoul Madjerembe ◽  
Mbou T. Pavel Rony ◽  
Djongnang Gabriel ◽  
...  
Keyword(s):  
Radial Growth ◽  
Colletotrichum Gloeosporioides ◽  
Disease Incidence ◽  
Severity Index ◽  
Anacardium Occidentale ◽  
In Vivo Experiments ◽  
Progress Curve ◽  
Cashew Tree

Aims: The aim of this work was to evaluate effect of Mancozeb 80 WP against Colletotrichum gloeosporioides, the agent responsible of anthracnose of cashew tree (Anacardium occidentale  L.). Study Design: The experimental design was in completely randomized blocks with three replications. Place and Duration of Study: in vitro and in vivo experiments were performed in Laboratory of  Department of Biological Sciences, University of Maroua during six months. Field trial was carried out in Kelo, Chad during three months. Methodology: Isolates were obtained from diseased organs (leaves and fruits) from Kélo in Chad and Maroua in Cameroon. The concentrations used in the laboratory were C1 (5 mg/ml), C2 (0.5 mg/ml), C3 (0.05 mg/ml), C4 (0.005 mg/ml), C5 (0.0 mg/ml). Radial growth, sporulation, conidial germination and pathogenicity were used to characterize and evaluate the effect of Mancozeb on the isolates in vitro. The preventive test was performed on three-month-old plants previously treated with Mancozeb. The concentration of 5 g/l was applied to the field and the incidence and severity were used to calculate the AUIPC (Area Under Disease Incidence Progress Curve) and AUSiPC (Area Under Disease Severity Index Progress Curve) curves. Results: Mancozeb reduced radial growth of all isolates at concentrations C1 (5 mg/ml), C2 (0.5 mg/ml) and C3 (0.05 mg/ml). The percentages of inhibition ranged from 50 to 100%. Mancozeb 80 WP completely (100%) inhibited the germination of C. gloeosporioides conidia in vitro. Mancozeb has protected cashew plants in vivo at the concentration C1 (5 mg/ml). AUIPC and AUSiPC were higher on control plants and lower on Mancozeb-treated plants. Conclusion: Mancozeb 80 WP may be associated in integrated pest management strategy against anthracnose.

scholarly journals Selecting Antagonistic Yeast for Postharvest Biocontrol of Colletotrichum gloeosporioides in Papaya Fruit and Possible Mechanisms Involved

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 760
Author(s):  
Hamizah Hassan ◽  
Mahmud Tengku Muda Mohamed ◽  
Siti Fairuz Yusoff ◽  
Erneeza Mohd Hata ◽  
Nor Elliza Tajidin
Keyword(s):  
Growth Inhibition ◽  
Colletotrichum Gloeosporioides ◽  
Biological Control Agent ◽  
Disease Incidence ◽  
Anthracnose Disease ◽  
Yeast Strains ◽  
Biocontrol Activity ◽  
Antagonistic Yeast

Colletotrichum gloeosporioides causes anthracnose disease in papaya fruit resulting in tremendous economic loss due to its latent infection. This study aimed to evaluate the biocontrol activity of antagonistic yeasts against C. gloeosporioides in papaya and determine the possible mechanism involved. One hundred and ten yeast strains were isolated from different parts of the papaya plant. Among them, only five strains, namely F001, F006, L003, FL013 and LP010, showed more than 55% radial growth inhibition of C. gloeosporioides. These five potent yeast strains were further evaluated in vitro and in vivo. The results indicated that strain F001 had the strongest biocontrol activity based on spore germination and fungal growth inhibition. In vivo, the strain F001 caused 66.7% and 25% reductions in disease incidence and severity, respectively. Based on molecular identification, the strain F001 was confirmed as Trichosporon asahii. Despite there was no significant induction of defense enzyme activities found on the treated fruits, SEM observation showed direct attachment of T. asahii with the fungal hyphae and interfere in their establishment to the fruit surface. Based on these findings, the antagonistic yeast T. asahii strain F001 may be used as a potential natural biological control agent against anthracnose disease in papaya fruit.

scholarly journals Development of a Fluorescent Tool for Studying Legionella bozemanae Intracellular Infection

2021 ◽  
Vol 9 (2) ◽  
pp. 379
Author(s):  
Breanne M. Head ◽  
Christopher I. Graham ◽  
Teassa MacMartin ◽  
Yoav Keynan ◽  
Ann Karen C. Brassinga
Keyword(s):  
Growth Kinetics ◽  
Legionella Pneumophila ◽  
Fluorescent Protein ◽  
Disease Incidence ◽  
Acanthamoeba Castellanii ◽  
Infection Model ◽  
Intracellular Infection ◽  
Green Fluorescent

Legionnaires’ disease incidence is on the rise, with the majority of cases attributed to the intracellular pathogen, Legionella pneumophila. Nominally a parasite of protozoa, L. pneumophila can also infect alveolar macrophages when bacteria-laden aerosols enter the lungs of immunocompromised individuals. L. pneumophila pathogenesis has been well characterized; however, little is known about the >25 different Legionella spp. that can cause disease in humans. Here, we report for the first time a study demonstrating the intracellular infection of an L. bozemanae clinical isolate using approaches previously established for L. pneumophila investigations. Specifically, we report on the modification and use of a green fluorescent protein (GFP)-expressing plasmid as a tool to monitor the L. bozemanae presence in the Acanthamoeba castellanii protozoan infection model. As comparative controls, L. pneumophila strains were also transformed with the GFP-expressing plasmid. In vitro and in vivo growth kinetics of the Legionella parental and GFP-expressing strains were conducted followed by confocal microscopy. Results suggest that the metabolic burden imposed by GFP expression did not impact cell viability, as growth kinetics were similar between the GFP-expressing Legionella spp. and their parental strains. This study demonstrates that the use of a GFP-expressing plasmid can serve as a viable approach for investigating Legionella non-pneumophila spp. in real time.

Metabolic importance of Na+/K+-ATPase activity during sea urchin development.

1997 ◽  
Vol 200 (22) ◽  
pp. 2881-2892 ◽  
Author(s):  
P Leong ◽  
D Manahan
Keyword(s):  
Enzyme Activity ◽  
Atpase Activity ◽  
Sea Urchin ◽  
Sodium Pump ◽  
Sea Water ◽  
Strongylocentrotus Purpuratus ◽  
Lytechinus Pictus ◽  
Stimulation Of

Early stages of animal development have high mass-specific rates of metabolism. The biochemical processes that establish metabolic rate and how these processes change during development are not understood. In this study, changes in Na+/K+-ATPase activity (the sodium pump) and rate of oxygen consumption were measured during embryonic and early larval development for two species of sea urchin, Strongylocentrotus purpuratus and Lytechinus pictus. Total (in vitro) Na+/K+-ATPase activity increased during development and could potentially account for up to 77 % of larval oxygen consumption in Strongylocentrotus purpuratus (pluteus stage) and 80 % in Lytechinus pictus (prism stage). The critical issue was addressed of what percentage of total enzyme activity is physiologically active in living embryos and larvae and thus what percentage of metabolism is established by the activity of the sodium pump during development. Early developmental stages of sea urchins are ideal for understanding the in vivo metabolic importance of Na+/K+-ATPase because of their small size and high permeability to radioactive tracers (86Rb+) added to sea water. A comparison of total and in vivo Na+/K+-ATPase activities revealed that approximately half of the total activity was utilized in vivo. The remainder represented a functionally active reserve that was subject to regulation, as verified by stimulation of in vivo Na+/K+-ATPase activity in the presence of the ionophore monensin. In the presence of monensin, in vivo Na+/K+-ATPase activities in embryos of S. purpuratus increased to 94 % of the maximum enzyme activity measured in vitro. Stimulation of in vivo Na+/K+-ATPase activity was also observed in the presence of dissolved alanine, presumably due to the requirement to remove the additional intracellular Na+ that was cotransported with alanine from sea water. The metabolic cost of maintaining the ionic balance was found to be high, with this process alone accounting for 40 % of the metabolic rate of sea urchin larvae (based on the measured fraction of total Na+/K+-ATPase that is physiologically active in larvae of S. purpuratus). Ontogenetic changes in pump activity and environmentally induced regulation of reserve Na+/K+-ATPase activity are important factors that determine a major proportion of the metabolic costs of sea urchin development.

scholarly journals Bioatividade de indutores de resistência no manejo da antracnose da goiabeira (Psidium guajava L.)

2016 ◽  
Vol 42 (2) ◽  
pp. 149-154 ◽  
Author(s):  
Rommel dos Santos Siqueira Gomes ◽  
Andréa Celina Ferreira Demartelaere ◽  
Luciana Cordeiro do Nascimento ◽  
Wendel Oliveira Maciel ◽  
Danilo Bruno Néri da Silva Wanderley
Keyword(s):  
Colletotrichum Gloeosporioides ◽  
Psidium Guajava

RESUMO A cultura da goiaba apresenta perdas em torno de 40 a 60% na pós-colheita relacionadas a problemas fitossanitários, como a antracnose causada pelo fungo Colletotrichum gloeosporioides. Pesquisas com métodos alternativos utilizando indutores de resistência têm sido bastante promissoras na busca de produtos com alto potencial no controle de patógenos em pós-colheita. Assim, o presente trabalho teve como objetivo avaliar os indutores de resistência no controle da antracnose e seus efeitos na qualidade físico-química em frutos de goiabeira ‘Paluma’. Os tratamentos utilizados foram: Agro-mós®, Ecolife®, Fosfitonova K®, Cuprogarb 500®, Rocksil® e testemunha (água destilada esterilizada). Realizou-se o teste in vitro, com discos de colônia de C. gloeosporioides (0,45 cm de diâmetro) com sete dias de cultivo e, postos em meio de cultura BDA acrescidos com os indutores. Foi determinada a porcentagem de inibição do crescimento micelial de C. gloeosporioides. O ensaio in vivo foi realizado com frutos de goiabeira variedade Paluma, desinfestados e tratados com indutores. Em seguida, discos de colônia do C. gloeosporioides foram inoculados e do primeiro ao oitavo dia após a inoculação, foram feitas avaliações do diâmetro das lesões nos frutos. As análises pós-colheita foram realizadas, avaliando a perda de massa fresca, sólidos solúveis totais (SST), acidez titulável (AT), razão SST/AT e potencial hidrogeniônico (pH). Foi utilizado o delineamento inteiramente casualizado, em esquema de parcela subdivididas 6x8 (tratamentos x período de avaliação) e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Os indutores Agro-mos®, Ecolife®, Fosfitonova K®, Cuprogarb 500® e Rocksil® inibiram o crescimento micelial do C. gloeosporioides in vitro, reduziram o diâmetro das lesões e mantiveram a qualidade pós-colheita em frutos de goiabeira ‘Paluma’.

scholarly journals Efeito fungitóxico do óleo essencial de aroeira da praia (Schinus terebinthifolius RADDI) sobre Colletotrichum gloeosporioides

2013 ◽  
Vol 15 (1) ◽  
pp. 150-157 ◽  
Author(s):  
L.F.G Oliveira Junior ◽  
R.B. Santos ◽  
F.O. Reis ◽  
S.T Matsumoto ◽  
W.M.S. Bispo ◽  
...  
Keyword(s):  
Colletotrichum Gloeosporioides ◽  
Tween 80 ◽  
Schinus Terebinthifolius

Neste trabalho foi avaliado o efeito do óleo essencial do fruto de Schinus terebinthifolius sobre o crescimento micelial do fungo Colletotrichum gloeosporioides in vitro, e no desenvolvimento da antracnose no período de pós-colheita em mamões. As diferentes concentrações de óleo foram diluídas em Tween 80 a 8%. No experimento in vitro foram preparados meios de cultura BDA nas concentrações de 0,05; 0,10; 0,25 e 0,50% do óleo essencial. O controle negativo foi realizado apenas com meio BDA e o controle solvente com meio BDA e Tween 80 a 8%. A inibição do crescimento do fungo foi diretamente proporcional à quantidade do óleo e a maior inibição encontrada foi de 79,07% na concentração de óleo de 0,50%. No experimento in vivo os frutos do mamoeiro foram inoculados com o fungo em quatro tratamentos: com biofilme; com biofilme mais 0,50% do óleo; com fungicida Prochloraz e frutos controle. Embora o tratamento com óleo tenha sido eficiente contra o fungo, não foi indicado comercialmente, pois apresentou valores elevados de perda de massa fresca, de firmeza, e também sintomas de fitotoxidade. O óleo tem propriedade antifúngica contra C. gloeosporioides in vitro e in vivo, contudo, não é recomendado para o mamão em função da fitotoxidez

scholarly journals Efeito In vitro e In vivo de filtrados de rizobactérias sobre Colletotrichum gloeosporioides Penz. do cafeeiro

2005 ◽  
Vol 29 (3) ◽  
pp. 553-561
Author(s):  
Gilvane Aparecida de Carvalho ◽  
Mário Sobral de Abreu ◽  
Denilson Ferreira de Oliveira ◽  
Mário Lúcio Vilela de Resende ◽  
Maria Floriana Esteves de Abreu
Keyword(s):  
Colletotrichum Gloeosporioides

Objetivou-se avaliar o efeito de filtrados derivados de culturas de rizobactérias na inibição da germinação de esporos de Colletotrichum gloeosporioides e confirmar sua ação antifúngica em relação à mancha manteigosa em mudas de cafeeiro. Foram conduzidos ensaios in vitro para testar 42 filtrados, identificando-se os de maior capacidade de inibir a germinação de esporos do fungo. Plântulas de café foram submetidas à inoculação com Colletotrichum e pulverização com quatro dos filtrados mais promissores. Os tratamentos constituíram um fatorial 4x4+2, combinando a aplicação de quatro filtrados com quatro modos de inoculação do fungo (ausência de inoculação e inoculação dois dias antes, junto, ou dois dias depois da aplicação dos filtrados). Uma testemunha absoluta e outra que recebeu somente o inóculo do fungo constituíram tratamentos adicionais. Após 35 dias, foram avaliados o crescimento do cafeeiro e a severidade da mancha manteigosa. Os filtrados apresentaram ampla variação quanto à atividade antifúngica in vitro e cinco deles inibiram completamente a germinação dos esporos. No experimento com planta, os filtrados tiveram eficácia similar contra a mancha manteigosa, com controle parcial da doença (35%). A aplicação dos filtrados teve efeito depressivo ao crescimento do cafeeiro, proporcionando menor produção de matéria seca em relação à testemunha absoluta.

scholarly journals Curcumin-removed turmeric oleoresin nano-emulsion as a novel botanical fungicide to control anthracnose (Colletotrichum gloeosporioides) in litchi

2021 ◽  
Vol 10 (1) ◽  
pp. 729-741
Author(s):  
Van Cuong Bui ◽  
The Tam Le ◽  
Tuyen Hong Nguyen ◽  
Nam Thi Pham ◽  
Hoang Dinh Vu ◽  
...  
Keyword(s):  
Field Trial ◽  
Colletotrichum Gloeosporioides ◽  
Inhibitory Concentration ◽  
Particle Sizes ◽  
Control Efficacy ◽  
Potent Inhibition ◽  
Nano Emulsion ◽  
Nano Formulation

Abstract During curcumin production in Vietnam, curcumin-removed turmeric oleoresin (CRTO) has been considered as a by-product. It costs to treat the by-product to prevent environmental pollution. In this study, the by-product was utilized as an active ingredient for preparing a botanical fungicide-based nano-emulsion and evaluated for its in vitro and in vivo control efficacy against Colletotrichum gloeosporioides, a causal agent of anthracnose of litchi, in the laboratory as well as a field trial. The nano-emulsion is colloidally stable and uniform with particle sizes of 95–250 nm. CRTO nano-emulsion significantly affected various Colletotrichum species. Notably, this nano-emulsion showed potent inhibition for the mycelial growth of C. gloeosporioides and solidly suppressed the development of anthracnose on litchi fruits. In the in vitro inhibition test, the equivalent half-maximal inhibitory concentration of CRTO in nano-formulation was 0.11 mg·mL−1, which was 3.0× and 6.1× lower than IC50 values of CRTO alone (0.33 mg·mL−1) and a mixture of curcuminoids (0.48 mg·mL−1), respectively. In the field trial, the litchi anthracnose infection was effectively controlled by nano-formulation. These results suggest that CRTO nano-emulsion could be used as an alternative to harmful synthetic fungicides to control anthracnose on litchi fruits.

scholarly journals A note on the antibiotic properties of Bacillus subtilis against Colletotrichum trifolii

2005 ◽  
Vol 73 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Y. Douville ◽  
J.G. Boland
Keyword(s):  
Bacillus Subtilis ◽  
Disease Incidence ◽  
Suppressive Effect ◽  
Mechanisms Of Action ◽  
Colletotrichum Trifolii ◽  
Growth Room ◽  
A Cell ◽  
Germ Tubes

The influence and mechanisms of action of Bacillus subtilis on Colletotrichum trifolii, a causal agent of anthracnose of alfalfa (Medicago sativa), were studied in vivo and in vitro. In growth room conditions, a cell-free culture filtrate of B. subtilis significantly reduced disease incidence and severity on alfalfa seedlings from 56% to 16% and from 2.0 to 1.2, respectively. Treatment of seedlings with washed cell suspensions of B. subtilis had no influence on disease. Applications of crude filtrate on alfalfa leaflets inoculated with C. trifolii were associated with reduced germination of conidia, lysis of conidia, and reduced formation of appressoria. Under in vitro conditions, crude filtrate reduced germination of conidia, and induced lysis of conidia and the formation of inflated germ tubes on germinating conidia. An antibiotic of the iturin family, iturin D, was tentatively identified as the active compound responsible for the suppressive effect of B. subtilis on C. trifolii.

scholarly journals Synergistic Antifungal Activity of Graphene Oxide and Fungicides against Fusarium Head Blight In Vitro and In Vivo

Nanomaterials ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2393
Author(s):  
Xiuping Wang ◽  
Fei Peng ◽  
Caihong Cheng ◽  
Lina Chen ◽  
Xuejuan Shi ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Plant Pathogens ◽  
Antimicrobial Agents ◽  
Plant Protection ◽  
Disease Incidence ◽  
Agricultural Science ◽  
Plant Diseases ◽  
Synergistic Activity

Plant pathogens constantly develop resistance to antimicrobial agents, and this poses great challenges to plant protection. Therefore, there is a pressing need to search for new antimicrobials. The combined use of antimicrobial agents with different antifungal mechanisms has been recognized as a promising approach to manage plant diseases. Graphene oxide (GO) is a newly emerging and highly promising antimicrobial agent against various plant pathogens in agricultural science. In this study, the inhibitory activity of GO combined with fungicides (Mancozeb, Cyproconazol and Difenoconazole) against Fusarium graminearum was investigated in vivo and in vitro. The results revealed that the combination of GO and fungicides has significant synergistic inhibitory effects on the mycelial growth, mycelial biomass and spore germination of F. graminearum relative to single fungicides. The magnitude of synergy was found to depend on the ratio of GO and fungicide in the composite. In field tests, GO–fungicides could significantly reduce the disease incidence and disease severity, exhibiting a significantly improved control efficacy on F. graminearum. The strong synergistic activity of GO with existing fungicides demonstrates the great application potential of GO in pest management.

Sign in / Sign up

Export Citation Format

Share Document