Ecological Complexity and the Success of Fungal Biological Control Agents

Choque

et al. 2018

Toxins

Ochratoxin A (OTA) is a mycotoxin produced by several species of Aspergillus and Penicillium that contaminate food and feed raw materials. To reduce OTA contamination, we first tested in vitro, actinobacterial strains as potential biocontrol agents and afterward, through a physical decontamination method using activated carbon fibers (ACFs). Actinobacterial strains were screened for their ability to reduce OTA in solid co-culture with A. carbonarius, which is the major OTA-producing species in European vineyards. Four strains showed a high affinity for removing OTA (67%–83%) with no significant effect on fungal growth (<20%). The mechanism of action was first studied by analyzing the expression of OTA cluster genes (acOTApks, acOTAnrps, acOTAhal) by RT-qPCR showing a drastic reduction in all genes (7–15 times). Second, the ability of these strains to degrade OTA was assessed in vitro on ISP2 solid medium supplemented with OTA (100 µg/L). Two strains reduced OTA to undetectable levels. As for the physical method, high adsorption rates were obtained for ACFs at 0.8 g/L with a 50% adsorption of OTA in red wine by AC15 and 52% in grape juice by AC20 within 24 h. These promising methods could be complementarily applied toward reducing OTA contamination in food chains, which promotes food safety and quality.

Section: Resultsmentioning

confidence: 99%

OTA Prevention and Detoxification by Actinobacterial Strains and Activated Carbon Fibers: Preliminary Results

Choque

et al. 2018

Toxins

“…Em bioprocessos agrícolas, a relação entre a expressão enzimática e a atividade antifúngica de leveduras, desempenha um papel muito importante no biocontrole de fitopatógenos como pode ser observado nas pesquisas realizadas por Hong et al (2017), onde a levedura interações interespecíficas tróficas e não tróficas ocorrem (Knudsen & Dandurand, 2014).…”

Section: A Ação Da Enzima β-13-glucanaseunclassified

Potencial de biocontrole das leveduras em pós-colheita de citros pela produção da enzima ²-1,3-glucanase e atividade killer: uma revisão

Rodrigues¹,

Silva²,

Alfaia³

et al. 2020

Citrus Res. Technol.

“…They reduce growth and survival of pathogen and infections caused by pathogens through competition, antibiosis, mycoparasitism, hyphal interactions, and enzyme secretion. Trichoderma are highly ecologically successful fungi and have been used increasingly in commercial agriculture (Knudsen and Dandurand, 2014). Success of biological control agents depends on the compatibility with other disease management systems.…”

Section: Introductionmentioning

confidence: 99%

Biocontrol Efficacy of Trichoderma spp. Against Phytophthora Blight of Pepper

Timila¹,

Manandhar²

2020

Nep. Hort.

Phytophthora blight (PB) caused by Phytophthora capsici Leonian is an economically important disease of pepper in Nepal. Experiments were conducted in epiphytotic conditions at Luvu, Lalitpur where severe outbreak of PB used to occur. The experiment was designed in randomized complete block with three replications. Three isolates of Trichoderma harzianum viz, T. harzianum (T22), T. harzianum (T69), and T. harzianum and one isolate of T. asperellum, were tested for their efficacy under the field conditions compared to chemical fungicides, copper oxychloride and fluazinam for two years, 2012 and 2013. In the first year experiment, the effect of all three isolates of T. harzianum was significantly different from the control. T. harzianum (T69), the local isolate was found better in reducing PB incidence and severity by 46% and 27% respectively during 2012. Similarly, in 2013 PB incidence and severity were reduced by 36% and 42% respectively and yield increased by 57% over control. However the chemical fungicides, fluazinam was the best treatment in reducing PB severity with increased yield by 70% followed by copper oxychloride that increased yield by 62% over control during 2013. There was no significant difference in efficacy of T69 and tested chemical fungicides. Hence, the use of Trichoderma harzianum (T69) could be one of the environmentally sound tools for the integrated management of Phytophthora blight.