The synergistic effects of Trichoderma harzianum AAUT14 and Bacillus subtilis AAUB95 on faba bean (Vicia faba L.) growth performance and control of chocolate spot compared to chemical fungicides under greenhouse conditions

ABSTRACT

Trichoderma harzianum AAUT14 and B. subtilis AAUB95 were evaluated compared to fungicides against chocolate spot using Ashebeka and Hachalu varieties of faba beans. In Ashebeka variety, upon 60 days of treatment (DOT), T. harzianum AAUT14+B. subtilis AAUB95 displayed the highest reduction of 50% disease incidence. Upon 80 DOT, Bio-agents inoculated plants showed 34–39% reduction of disease incidence. The disease severity (DS) reduction was much pronounced upon 80 DOT, 41–55% as a function of time. Similarly, T. harzianum AAUT14 + B. subtilis AAUB95 showed 54% DI reduction of upon 80 DOT compared to MORE 720 WP (56%) and ORZEB 80 WP (53%) in Hachalu variety. There was no significance difference (P > 0.05) observed between MORE 720 WP and the co-inoculation. The nitrogen and phosphorus was improved by the bio-agents. Thus, the mixture of T. harzianum AAUT14 and B. subtilis AAUB95 can be used as bio-fungicides of chocolate spot growth promoting agents of faba beans.

KEYWORDS:

• Botrytis fabae
• Disease severity
• faba bean
• fungicides
• in vivo
• Trichoderma harzianum AAUT14

Acknowledgements

The authors would like to thank Addis Ababa University, Department of Microbial, Cellular and Molecular Biology for providing all the laboratory facilities and financial support of this study, Madda walabu University, Department of Biology for the financial support and Holleta Agricultural Research Center for providing faba bean varieties and the Rhizobium leguminosarum bv. viciae (FB-1035).

Disclosure statement

Authors have declared that no competing interests exist.