AIM: To evaluate biological control agents (BCA) against Fusarium graminearum on infected maize stalks as a means to reduce Fusarium head blight (FHB) in subsequently grown wheat. METHODS AND RESULTS: In the laboratory, BCAs were applied against F. graminearum on maize stalk pieces. Clonostachys rosea inhibited the perithecia development and ascospore discharge when applied before, simultaneously with and after the pathogen. In the field, we simulated a system with high disease pressure, i.e. maize-wheat rotation under no-tillage, by preparing maize stalks inoculated with F. graminearum. The infected stalks were treated with formulations of C. rosea selected in vitro, or the commercial BCA strain Trichoderma atrobrunneum ITEM908 and exposed to field conditions over winter and spring between winter wheat. Monitoring with spore traps and of FHB symptoms, as well as quantification of F. graminearum incidence and DNA in harvested grain revealed significant reductions by C. rosea by up to 85, 91, 69 and 95% compared with an inoculated but untreated positive control, respectively. Deoxynivalenol (DON) and zearalenone (ZEN) contents were reduced by up to 93 and 98%, respectively. Treatments with T. atrobrunneum were inconsistent, with significant reductions of DON and ZEN under warm and wet climatic conditions only. CONCLUSIONS: The findings support application of C. rosea against F. graminearum on residues of maize to suppress the primary inoculum of FHB. IMPACT OF THE STUDY: As sustainable agriculture requires solutions against FHB, the application of C. rosea during the mulching of maize crop residues should be evaluated in on-farm experiments. This article is protected by copyright. All rights reserved.
AIM: To evaluate biological control agents (BCA) against Fusarium graminearum on infectedmaize stalks as a means to reduce Fusarium head blight (FHB) in subsequently grown wheat. METHODS AND RESULTS: In the laboratory, BCAs were applied against F. graminearum on maize stalk pieces. Clonostachys rosea inhibited the perithecia development and ascospore discharge when applied before, simultaneously with and after the pathogen. In the field, we simulated a system with high disease pressure, i.e. maize-wheat rotation under no-tillage, by preparing maize stalks inoculated with F. graminearum. The infected stalks were treated with formulations of C. rosea selected in vitro, or the commercial BCA strain Trichoderma atrobrunneumITEM908 and exposed to field conditions over winter and spring between winter wheat. Monitoring with spore traps and of FHB symptoms, as well as quantification of F. graminearum incidence and DNA in harvested grain revealed significant reductions by C. rosea by up to 85, 91, 69 and 95% compared with an inoculated but untreated positive control, respectively. Deoxynivalenol (DON) and zearalenone (ZEN) contents were reduced by up to 93 and 98%, respectively. Treatments with T. atrobrunneum were inconsistent, with significant reductions of DON and ZEN under warm and wet climatic conditions only. CONCLUSIONS: The findings support application of C. rosea against F. graminearum on residues of maize to suppress the primary inoculum of FHB. IMPACT OF THE STUDY: As sustainable agriculture requires solutions against FHB, the application of C. rosea during the mulching of maize crop residues should be evaluated in on-farm experiments. This article is protected by copyright. All rights reserved.
Authors: Jonathan M Palmer; Philipp Wiemann; Claudio Greco; Yi Ming Chiang; Clay C C Wang; Daniel L Lindner; Nancy P Keller Journal: J Ind Microbiol Biotechnol Date: 2021-12-23 Impact factor: 3.346