Biocontrol potential of different trichoderma isolates against maize phytopathogens

Abstract

Usage of chemical plant protection agents in agricultural production contributes to environmental pollution and emissions of factors harmful for human health. It has been noted that their overexploitation has resulted in the emergence of resistant species and chemical compounds in the food chain, which indicates the need to find new agents with improved characteristics. One of the solutions is certainly the use of beneficial microorganisms. Considering that maize is a significant agricultural crop very present in the human diet, its health safety is of great importance. In this paper, the ability of three Trichoderma isolates, isolated from the environment, in the biological control of the most common maize pathogens, was examined. Cultivation of Tricoderma isolates was performed on PDB (Potato Dextrose Broth) medium by shaking at 150 rpm for 7 days at 25°C. After 7 days of cultivation, the effect of both, cultivation broth and supernatant, against selected maize phytopathogens was examined using wells diffusion technique. The results showed that the cultivation broth showed a statistically significant efficacy on selected maize phytopathogens compared to the supernatant, using all Trichoderma isolates. By applying the Scheffe test, it was determined that the best effect on the test maize phytopathogens show cultivation broth of T. harzianum, forming maximum mean inhibition zone diameters of 50.33 mm for Fusarium graminearum, 40.67 mm for Helminthosporium carbonum, 25.67 mm for Aspergillus flavus and 25.33 mm for Penicillium sp. Since each inhibition zone larger than 22 mm shows that the produced agent is highly efficient, based on the obtained inhibition zone diameters of all tested isolates, it can be concluded that the produced T. harzianum cultivation broth shows high efficacy against four maize phytopathogens in vitro. This results once again confirms the great potential of Trichoderma isolates in biological control, which certainly contributes to the development of sustainable agricultural production and consequently has a positive impact on human health.