Biochar and Trichoderma aureoviride applied to the sandy soil: effect on soil quality and watermelon growth

Trichoderma spp. are an alternative to increase plant growth and as biological control agents of diseases. Biochar added to soil and Trichoderma can result in the enhancement of crop development and can aid in preventing fertilizer run-off, improving plant health, retaining soil moisture, and helping plants through drought periods. However, a knowledge gap remains regarding the combined effect of biochar and Trichoderma on soil quality and crop growth. The objective of the present study was to evaluate this combined effect and show a new approach of biochar as a route of T. aureoviride (T) inoculation. We evaluated three sources of biochar, bean husks, coffee grounds, and coffee husks, with or without T and additional control that was devoid of biochar and T. The association of all biochar sources with T showed a significant increase in watermelon growth and soil quality. Biochar coffee grounds with T increased urease, β-glucosidase, and total organic carbon, showing the potential of this combination in these processes. Watermelon plants cultivated in soil with coffee grounds and T showed plant length and shoot dry biomass increases of 129% and 192%, respectively. Thus, this study found that biochar use plays an important role in the effectiveness of T. aureoviride applications and is a new instrument for sustainable agriculture.

Effect of biochar and inoculation with Trichoderma aureoviride on melon growth and sandy Entisol quality

The melon belongs to the family of commercially important cucurbitaceous in the world. However, the production of this crop can be very problematic in some places due to management practices and the climatic instability. Amongst the different options available to overcome these obstacles, the use of biochar often promoted for providing multiple benefits to crops, could contribute in holding more water and nutrients in soil and therefore improve the plant growth. A second way to try to improve the plant development was to use Trichoderma (TRI) known as aiding in seed germination, and being an excellent biological control agent against plant pathogenic pests. So, the objective of this study was to evaluate the benefits of the association of biochar and TRI on the initial growth of melon and the effects on the quality of a sandy Entisol. We quantified the effects of these associations through biometric growth in melon plants and chemical, microbial, and enzymatic activities of the biogeochemical cycles in the soil. An experiment in a completely of randomized design was performed in a factorial scheme (3 x 2 + 1) with three sources of biochar (bean husk (BH), coffee ground (CG), and coffee husk (CH)) inoculated with (T+) or without (T-) TRI and additional controls When the coffee grounds (CG) and bean husks (BH) biochar with T+ soil was inoculated, the fresh weight (number of leaves), dry weight, length (of roots and branch), soil acid and alkaline phosphatase, total organic carbon, phosphorus, magnesium, potassium, and pH were all increased. Moreover, T. aureoviride inoculated CG biochar compared to the control increased the shoot length and dry biomass of the melon plant in 30 and 22% between 22 and 30 %. The soil that received coffee husks (CH) biochar and T+ showed higher microbial biomass carbon. However, the melon plants responded more to the type of biochar than to the T. aureoviride inoculation, possibly due to the short growth time of melon. Results of BH biochar inoculated with T. aureviride in sandy soil showed improved efficiency on melon growth and increased soil quality.

EVALUACIÓN DEL CRECIMIENTO Y DESARROLLO DE Trichoderma aureoviride TAT-1 EN UNA FERMENTACIÓN DE ESTADO SÓLIDO SOBRE EL SUBSTRATO ARROZ

Se tuvo como objetivo determinar la forma de crecimiento y desarrollo y la producción de conidios de Trichoderma aureoviride TAT-1 sobre el substrato arroz, por fermentación de estado sólido, con diferentes niveles de humedad (70, 76 y 82%) y de cantidad de arroz (0,39 y 0,72 g) por centímetro cuadrado de superficie de la cama del biorreactor. La fermentación se hizo en un biorreactor tipo pila de discos modificado durante 7 días a 22°C con luz blanca permanente y con una aireación de 2 VVM. Se observó que Trichoderma aureoviride TAT-1, macroscópicamente, crece y desarrolla en forma de una capa fina de micelio blanco más o menos asentado sobre el arroz a los dos días de incubación y de un color verde homogéneo (correspondiente a la fase de esporulación) desde el tercer día hasta el término de la fermentación. Se determinó que la mayor producción de conidios fue de 2,74x10^9 con / g, correspondiente al nivel más bajo de humedad (70%) y cantidad de substrato arroz (0,39 g/ cm2) trabajado.

The antagonistic properties of Trichoderma spp. inhabiting woods for potential biological control of wood-damaging fungi

The antagonistic potential of Trichoderma spp. for biological control of wood-damaging fungi was investigated in the present paper. In vitro assays to investigate antifungal characteristics of Trichoderma spp. were conducted with various wood-damaging fungi. Exo-chitinase activity of the isolates was also measured. Three typical wood decayers and three sap-stainers served as target fungi. The antagonistic abilities of each Trichoderma species differed markedly according to the target fungus. The growth inhibition rates shown by the non-volatile metabolites against the wood decayers reached 100% for Trichoderma harzianum KUC1459. The antibiotics produced by Trichoderma dorotheae KUC5027, a recently reported species of Trichoderma, revealed strong antagonistic effects against sap-stainers. Trichoderma gamsii KUC1747 effectively inhibited the growth of all wood-damaging fungi in dual culture tests. The exo-chitinases of Trichoderma longibrachiatum KUC1540, Trichoderma aureoviride KUC1335, and T. harzianum KUC1459 showed significantly high activity.