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Porcentaje de Inhibición de crecimiento radial causado por Trichoderma harzianum, (Comercial), sobre Nakataea, Rhizoctonia y Sclerotium.
Source publication
It has studied the antagonistic capacity a commercial Trichoderma harzianianum, against a Rhizoctonia spp., Nakatea sigmoide y Sclerotium rolfsii, causing the rot of stems and pods of rice, as well as its effect on 14 native strains of Trichoderma isolated of different rice fields. The in vitro test showed that T. harzianum presents a high antagoni...
Citations
... Especies como T. harzianum han presentado una alta actividad antagonista e hiperparasitaria contra Rhizoctonia sp., igualmente cepas de T. viride limitan el desarrollo de patógenos del suelo tales como R. solani, Fusarium spp., Sclerotium rolfsii durante ensayos in vitro igualmente, estos fitopatógenos también Eficacia de biofungicidas para el manejo de la costra negra (Rhizoctonia solani Kühn) de la papa Betancourth Información Tecnológica -Vol. 33 Nº 1 -2022 muestran susceptibilidad a T. koningii así como a otras especies micoparasitarias y productoras de metabolitos secundarios (Garrido y Vilela, 2019). También se ha determinado un efecto inhibidor significativo de T. virens sobre R. solani, asociado con genes para el hiperparasitismo y la antibiosis, que incluyen proteasas extracelulares, transportadores de oligopéptidos, receptores acoplados a proteína G, quitinasas, glucanasas, proteasas, proteínas de resistencia a la tetraciclina y reductasas (Halifu et al., 2020). ...
This research study assessed the efficacy of biofungicides for managing the pathogenic fungus Rhizoctonia solani Kühn in potato crops at three different sites in the state of Nariño (Colombia). A randomized complete block experimental design with three replicates was performed in plots with a high incidence of rhizoctoniasis disease (black scurf). The treatments included a control (T1), Penthiopyrad chemical control (T2), Trichoderma spp. (T3), Bacillus subtilis (T4), Pseudomonas aeruginosa (T5), and the biostimulant Nointox® (T6). The results showed significant differences between treatments and the control, achieving a lower incidence of rhizoctoniasis disease during sprouting and tuberization stages. Yields were highest at the Santa Ana de Tuquerres (Nariño, Colombia) site, but this may be due to environmental factors. It is concluded that the fungicide Pentiopirad, Trichoderma spp., and Bacillus subtilis showed the most promising features for managing R. solani in potato crops.
... Plant beneficial microbes (PBMs) minimize agrochemical inputs, enhance tolerance to biotic-abiotic stresses, and increase plant nutrition. Thereby, the introduction of PBMs in production systems is an excellent strategy to guarantee crop yield and efficiency (Barnwal et al. 2013;Rondoy and Severino 2019). Within these strategies, seed coating with beneficial microorganisms for cultivation is playing an outstanding role (Moïse et al. 2005;Pedrini et al. 2017;Kuchlan et al. 2019). ...
Seed coating is a technique to cover seeds with external agents to upgrade their performance, handling, and plant establishment. Plant beneficial microbes (PBMs), such as plant growth-promoting bacteria, mycorrhizal fungi, and other fungi (e.g., Trichoderma spp.), decrease agrochemical inputs, enhance tolerance to biotic-abiotic stresses, and increase essential plant nutrition. The demand for pre-treated seeds as delivery systems for biological agents is advancing. Here, a seed coating formulation containing Trichoderma koningiopsis is presented. The physicochemical and biological characterization of the seed coating prototypes included drying protector screening, the effect of the inoculum concentration on survival, the assessment of microbial release profiles in soil extract, and plant tissue colonization capability under semi-controlled conditions. Gelatine and pectin, two of the tested drying protectors, maintained fungus germination after 60 days at 18 °C with significantly higher values of up to 38% compared with the control. The initial concentration of 10⁶ colony-forming units (CFU) per seed undergoes a positive effect on survival over time. Regarding plant tissue colonization, the fungus establishes endophytically in rice. In conclusion, seed coating is a promising alternative for the formulation of beneficial microbial agents such as Trichoderma sp., maintaining cell survival and further promoting the establishment in rice systems.
Key points
• Enhancing drying survival of T. koningiopsis formulates
• Seed coating formulation approach for T. koningiopsis in rice
• Colonization capacity of formulated T. koningiopsis in rice tissue
The research proposes a biofertiliser from mycorrhiza and rhizobium evaluating its antagonistic capacity and biotisation in the cultivation of vegetables with a DCA, the sample considers the potato, pea, and barley in the Huasahuasi Peruvian District, with nine treatments in three formulas, considering a control group without inoculation and two repetitions. As a result, the optimal formula is obtained with 300 g of mycorrhizal and rhizobium strains + 500 g of black soil + 200 g of potato peel crust, which has an effective antagonistic capacity of 100% in pea cultivation, 90% in the barley, and 85% in the potato, besides that it achieves a biotisation in the cultivation of peas of 95%, in the barley 100% and in the potato 90%.
p> Background: Biocontrol of grapevine trunk diseases (GTDs) is a friendly alternative to chemical control that cause resistance and contamination of the ecosystems. Objective: isolate native grapevine root and rhizosphere microorganisms with biocontrol potential of grapevine trunk fungi diseases. Methodology: The competition for substrate (CS) was studied with the Bell´s scale, contact time (CT) between the antagonist-pathogen (days) and the growth inhibition percentage (GIP). Results: Seven Trichoderma strains were isolated (from roots: Tr-1, Tr-2, Tr-3, Tr-6; and from rhizosphere: Tr-4, Tr-5 Tr-7); six Bacillus spp. (from roots: Bac-4, Bac-5, Bac-6; and from rhizosphere: Bac-1, Bac-2, Bac-3); and two Streptomyces sp. (Act-1, Act-2). The CS results evaluated with the Bell scale showed Tr-1, Tr-7, T.atv ( Trichoderma atroviride ) and T-22 ( Trichoderma harzianum ) were placed in class 1 against Lasiodiplodia theobromae and, all isolates were placed in class 1 against Campylocarpon pseudofasciculare and Phaeoacremonium parasiticum . The CT of Trichoderma was 2 days ( L. theobromae ) and 3 days ( C. pseudofasciculare and P. parasiticum ). In the antibiosis test, Tr-5 ( Trichoderma ) and Bac-3 ( Bacillus ) had the highest GIP values (>50%) against the different evaluated pathogens. The isolate Act-2 ( Streptomyces sp.) presented a GIP, >70% ( L. theobromae ), and >40% ( C. pseudofasciculare) and >30% ( P. parasiticum ). Implications: The use of biological control in the management of grapevine trunk diseases is an effective tool, and can be integrated into an integrated management strategy for these pathologies. Conclusions: The native isolates Bac-3 ( Bacillus spp.), Tr-5 ( Trichoderma spp.), Act-2 ( Streptomyces sp.) demonstrated in vitro control against the pathogens L. theobromae , C. pseudofasciculare and P. parasiticum , pathogens associated to grapevine trunk diseases.</p
Globally, corn is the most economically important crop, surpassing crops such as wheat, rice and barley. However, the presence of pathogenic fungi associated with corn, have favoured the appearance of diseases that cause economic loss. Therefore, the aim of the present study is to assess the efficacy of treatments in vitro and in vivo with Trichoderma asperellum in controlling the disease severity and the yield reduction in corn plants caused by Fusarium verticillioides and Ustilago maydis. In vitro confrontation experiments demonstrated the high antagonistic capacity of the T. asperellum strains, which is able to reduce the radial growth of the pathogen’s colonies from 88.71% up to 100%. In the field experiments treatments 6 and 7, where T. asperellum was confronted with F. verticillioides and U. maydis, showed a significant reduction in the average damage of the disease by 8.3 ± 6.7 and 9.5 ± 3.0, and an increase in their grain yield by 4.43 ± 0.33 and 4.11 ± 0.15 t/ha, respectively. Similarly, the percentage of good ears of 66.75 ± 5.4 and 70.37 ± 5.4, obtained in treatments 6 and 7, was higher than those values obtained in treatments 2 and 3 without Trichoderma confrontation. These results indicate that the selected Trichoderma strains isolated from Zea mays could effectively control these phytopathogenic fungi in field.
La calidad y rendimiento en los sistemas de producción de papa se ve seriamente afectado por enfermedades por hongos como Rhizoctonia solani, cuyo control químico es ineficiente. El objetivo de este trabajo fue seleccionar aislamientos de Trichoderma spp. in vitro como potenciales biofungicidas para el control de R. solani en papa. A partir de muestras de suelo de los departamentos Calamuchita, Río Primero, Punilla y San Javier, de la provincia de Córdoba (Argentina), se aislaron e identificaron genéticamente 18 cepas nativas de Trichoderma. A través de cultivos duales in vitro se evaluó la competencia por el sustrato, micoparasitismo y capacidad de antibiosis. Se identificaron cinco cepas promisorias: T. atroviride ACp8 y CBa3, T. konigiopsis CBk2 y CBk4 y T. harzianum CBh2. Estas cepas presentaron un sobrecrecimiento mayor al 85 % sobre el patógeno; fueron muy competitivas por el sustrato (Grado 1) y presentaron una elevada capacidad de antibiosis mayor al 35 % lo que inhibió el crecimiento radial por al menos cuatro mecanismos de interacción hifal frente a R. solani. Las cepas seleccionadas que reconocen específicamente al fitopatógeno y presentan alta adaptación edafoclimática por su condición de nativas, podrán ser incorporadas al manejo del cultivo favoreciendo la sustentabilidad del sistema.
