Trichoderma Strains Outperform Carbendazim in Controlling Major Sorghum Fungal Diseases

A new study published in the Egyptian Journal of Biological Pest Control reveals that Trichoderma harzianum and T. viride offer highly effective natural control of damaging sorghum fungal pathogens—often outperforming the widely used fungicide carbendazim.

Sorghum growers worldwide face severe losses from pathogens causing grain mold, stalk rot, and charcoal rot. Conventional fungicides pose risks to human health and the environment, and resistance is increasingly common. The researchers investigated whether Trichoderma species could serve as safer, more sustainable biocontrol agents.

Using a suite of laboratory assays—including dual culture tests, culture filtrate inhibition studies, and ethyl acetate extract analyses—the team compared the biocontrol abilities of T. harzianum and T. viride across six major fungal pathogens.

Key Findings

✔ Both Trichoderma species strongly inhibited pathogen growth.
T. viride demonstrated the highest inhibitory activity, suppressing Exserohilum rostratum by 89% and Fusarium proliferatum by 84.4%.
✔ Carbendazim showed limited effectiveness.
Two major pathogens—E. rostratum and Macrophomina phaseolina—were completely resistant at all tested concentrations.
✔ Trichoderma extracts displayed potent antifungal action.
Ethyl acetate extracts inhibited all pathogens, with F. chlamydosporum being the most sensitive (MIC: 0.5–1.0 mg/disk).
✔ T. harzianum exhibited true mycoparasitism.
Microscopy revealed hyphal coiling, penetration, appressoria formation, and enzymatic lysis of pathogens—indicating a direct parasite-like mode of action.

Why This Matters

The discovery is significant for sustainable agriculture, especially in regions heavily reliant on sorghum. As chemical fungicides lose effectiveness, natural biocontrol agents offer a safer alternative that reduces environmental harm and residue risks.

Conclusion

The authors conclude that both T. viride and T. harzianum are strong candidates for developing bio-fungicide formulations that can replace or complement chemical fungicides like carbendazim—particularly against resistant strains.

Reference

Yassin, M.T., Mostafa, A.AF. & Al-Askar, A.A. In vitro antagonistic activity of Trichoderma harzianum and T. viride strains compared to carbendazim fungicide against the fungal phytopathogens of Sorghum bicolor (L.) Moench. Egypt J Biol Pest Control 31, 118 (2021). https://doi.org/10.1186/s41938-021-00463-w