Soil quality and the disturbances generated by various agronomic operations directly influence the physicochemical and biological properties of the soil. These factors determine the microbiological diversity present, which in turn affects agricultural productivity. Microorganisms such as species of the genus Trichoderma play a key role in this balance thanks to their ability to adapt to conditions such as pH, salinity and temperature among others (Hernández et al., 2019).
Trichoderma is a cosmopolitan fungus of biotechnological interest and recognised for its ability to produce metabolites of agricultural interest, such as enzymes, plant growth promoting compounds and volatile compounds. This fungus is found both in nutrient-rich organic composite soils and in extreme environments. Its survival and success under different conditions is due to nutritional strategies ranging from saprophytic to biotrophic and necrotrophic behaviour (Miramontes, 2022).
In addition, the genetic evolution of the genus Trichoderma has allowed the emergence of specialised species capable of producing secondary metabolites, proteins and enzymes adapted to particular physicochemical conditions. This ability to adapt to pH, temperature and other environmental factors makes it a powerful tool for the agricultural sector (Miramontes, 2022, Meyer et al., 2022).
Studies by Häkkinen (2015) showed that more than 940 genes of the genus Trichoderma are differentially regulated in response to pH, which reinforces its ability to thrive in diverse conditions.
Thanks to its adaptability, easy isolation and manipulation, the genus Trichoderma has established itself as an indispensable resource in the biotechnological industry applied to agriculture.
Therefore, in order to obtain effective biofertilisers based on Trichoderma, it is essential to select strains with a high capacity to adapt to different physicochemical conditions. This guarantees their establishment in the rhizosphere of plants and therefore the restoration of the microbial balance, thus achieving strengthened and highly productive crops.
TRICHODEX® (Fertiberia Group) has in its catalogue VELLTRIX®, a registered biofertiliser, formulated with Trichoderma asperellum, characterised by its high adaptive power to different physicochemical conditions, with rhizosphere bacteria and mycorrhizae, creating a balanced and highly effective microbial consortium.
The comparative approach in its development ensures that VELLTRIX® is a robust tool, capable of adapting to the demands of the soil and providing an improvement in crop productivity. VELLTRIX® stands out for its extraordinary adaptability, the result of a rigorous selection process and comparative tests. In these studies, our strain showed a clear superiority over others of the same genus, validating its ability to establish and thrive in diverse physicochemical conditions.
To determine the adaptive potential of different Trichoderma sp. strains, in vitro studies have been performed under different conductivity and temperature conditions.
In vitro growth tests of different Trichoderma strains in different saline concentrations
The data show that the growth of each species differs significantly between them, even at the isolate level, according to the NaCl concentrations over the 7 days tested.
Analysing the results of the higher concentration, it shows that the Trichoderma asperellum isolates have a higher growth rate at this concentration, differentiating them from the rest, with T. asperellum (VELLTRIX®) standing out among all the isolates tested. Furthermore, at a concentration of 0.75M T. asperellum (VELLTRIX®) is the only sporulating fungus.
The presence of letters indicates statistical differences. ANOVA, (Duncan p<0.05)
In vitro growth tests of different Trichoderma sp. strains at different temperatures
The study of the growth of the different species at different temperatures again shows the variability of growth between strains and isolates, especially at high temperatures (>25°C).
Analysis of growth at 30°C shows that each strain is more or less resistant to high temperatures, with T. asperellum (VELLTRIX®) again standing out with a higher growth rate.
The presence of letters indicates statistical differences. ANOVA, (Duncan p<0.05)
In addition to the above tests, the ability of Trichoderma asperellum to grow at different pH types has been demonstrated.
In vitro growth tests of Trichoderma asperellum at different pH
The study of the growth of T. asperellum (VELLTRIX®) at different pH demonstrates once again the capacity of this strain to adapt to different conditions, managing to grow between pH 2 and 7.
CONCLUSIONS
The growth rate of the different Trichoderma sp. tested subjected to different conductivity and temperatures, differs significantly depending on the species and/or isolate.
The Trichoderma asperellum isolate belonging to the VELLTRIX® formulation has a high capacity to withstand salinity, pH and high temperature conditions in in vitro tests.
The adaptive properties of T. asperellum (VELLTRIX®) confer to it high survival in hostile environments, improving its establishment and efficiency in soil subjected to different physicochemical conditions.
REFERENCES
- Meyer, M. C., Mazaro, S. M., da Silva, J. C., MAZARO, S. M., & DA SILVA, J. C. (2022). Trichoderma: su uso en la agricultura.
- Hernández-Melchor, D. J., Ferrera-Cerrato, R., & Alarcón, A. (2019). Trichoderma: importancia agrícola, biotecnológica, y sistemas de fermentación para producir biomasa y enzimas de interés industrial. Chilean journal of agricultural & animal sciences, 35(1), 98-112.
- Cabral Miramontes, J. P. (2022). Descripción de mecanismos de adaptación de cepas de Trichoderma spp. aisladas del Estado de Nuevo León a variaciones en el pH (Doctoral dissertation, Universidad Autónoma de Nuevo León).
- Häkkinen, M., Sivasiddarthan, D., Aro, N., Saloheimo, M., & Pakula, T. M. (2015). The effects of extracellular pH and of the transcriptional regulator PACI on the transcriptome of Trichoderma reesei. Microbial cell factories, 14(1), 1-15.
- Mukherjee, P. K., Horwitz, B. A., Singh, U. S., Mukherjee, M., & Schmoll, M. (Eds.). (2013). Trichoderma: biology and applications. CABI.
