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Fusarium head blight (FHB) is one of the most important cereal diseases worldwide, causing yield losses and contamination of harvested products with mycotoxins. Fusarium graminearum is one of the most common FHB-causing species in wheat and barley cropping systems. We assessed the ability of different botanical extracts to suppress essential stages of the fungal life cycle using three strains of F. graminearum (FG0410, FG2113, and FG1145). The botanicals included aqueous extracts from white mustard (Sinapis alba) seed flour (Pure Yellow Mustard [PYM] and Tillecur [Ti]) as well as milled Chinese galls (CG). At 2% concentration (wt/vol), PYM and Ti completely inhibited growth of mycelium of all F. graminearum strains whereas, at 1%, CG reduced the growth by 65 to 83%, depending on the strain. While PYM and Ti reduced the germination of both conidia and ascospores at 2% (wt/vol), CG was only effective in reducing conidia germination. Perithecia formation of FG0410 but not FG2113 was suppressed by all botanicals. Moreover, application of botanicals on mature perithecia led to a two- to fourfold reduction in discharge of ascospores. Using liquid chromatography (LC) with diode array detection, we quantified the principal glucosinolate component sinalbin of PYM and Ti. LC time-of-flight mass spectrometry was used to demonstrate that the bioactive matrix of CG contains different gallotannins as well as gallic and tannic acids. Possible antifungal mechanisms of the botanical matrices are discussed. The results of this study are promising and suggest that PYM, Ti, and CG should be explored further for efficacy at managing FHB. [Formula: see text] Copyright © 2019 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

The majority of Dutch farmers perceive that mouldboard ploughing prior to potato planting is necessary, despite its negative impacts on inherent soil fertility and soil structure. An innovative agronomic practice in Dutch organic agriculture is the use of cut-and-carry fertilizers with which above-ground biomass of crops with high nitrogen content (e.g. grass/clover) is harvested and transferred to other fields as plant-based fertilizers. The objective of this study was to investigate the interactive effects of two tillage systems (reduced tillage (RT), standard tillage (ST)) and three organic fertilizer amendments (solid cattle manure (SCM), lucerne pellets (LP), grass/clover silage (GCS)) on crop performance and nitrogen utilization of organic potato. Use of RT decreased tuber yield by 13.4 % compared to ST due to lower average tuber size which was related to higher soil bulk density and increased vulnerability to drought stress during tuber bulking. On the other hand, use of RT positively affected nitrogen utilization and tuber quality in terms of specific gravity, dry matter and starch contents. However, the price premium associated with enhanced tuber quality may not offset the observed yield gap between RT and ST. Plant-based fertilizers enhanced nitrogen utilization in terms of apparent nitrogen recovery compared to animal-based. Although use of LP resulted in the highest yield for both tillage systems, its high price may be cost-inhibitive. An integrated approach taking into account N release patterns, environmental conditions, final yields, and production costs is needed in order to optimize resource use efficiency and overall profitability for farmers.

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Aim: To evaluate biological control agents (BCAs) 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, that is, a 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 rows. 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 the application of C. rosea against F. graminearum on residues of maize to suppress the primary inoculum of FHB. Significance and Impact of the Study: As sustainable agriculture requires solutions to control FHB, hence, the application of C. rosea during the mulching of maize crop residues should be evaluated in on-farm experiments.

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