Disease Management and Estimated Effects on DON (Deoxynivalenol) Contamination in Fusarium Infested Barley

Abstract

Fusarium head blight (FHB or scab) economically devastates barley production. FHB is predominantly caused by Fusarium graminearum and has resulted in major reductions in the quality of barley in the United States. The most common source of economic loss is through development of potent mycotoxins in the grain, the most prominent of which, in the United States, is deoxynivalenol (DON). DON levels can be managed through a variety of techniques. This study presents the estimate of the statistical relationship among DON contamination in barley, FHB incidence and severity, and a variety of disease management techniques. Data from 22 field studies and a survey of barley producers are used to estimate the relationship. Fungicide applications reduce DON in barley in general and via complementary interactions with the barley cultivar. Genetic FHB resistance in barley varieties is an important determinant of DON levels, as well as previous crop and factors related to time and location. Taking care to avoid rotations with FHB host crops immediately prior to barley is also important to reduce DON levels in barley. These become key inputs into barley producer decisions for evaluating the economic value of adopting FHB management techniques. DON in barley results in substantial price reductions, downgrading to feed barley, or even rejection for barley producers in the Northern Great Plains. Another consequence occurs when barley producers modify production choices, such as including crops less vulnerable to FHB [4].Management of FHB caused by F. graminearum relies on an integrated program using genetic resistance, fungicides, and cultural practices such as tillage, adjusting planting dates, and crop rotation. Employment of several management tools together has the greatest effect on decreasing losses due to FHB and DON in wheat [5,6]. Breeding resistance towards FHB remains a top priority to prevent economic losses as it holds potential for economical FHB control in barley. Limited host resistance has been an objective of wheat and barley cultivar breeding programs [1]. In wheat, the use of a moderately resistant (low DON accumulating) cultivar with a prothioconazole plus tebuconazole fungicide application when 50% of the main stems are at full head, currently provides the greatest amount of FHB and DON reduction in the Northern Great Plains [7].Observations of wheat yield loss from FHB are often reported anecdotally, and generally a statistical relationship between FHB and yield is not contemplated. As stated in Salgad et al. [8], estimating such a relationship requires observations of FHB, DON, yield, test weight, and a proposed model of their relationship. Relationships between grain quality and FHB have been observed [9][10][11]. These relationships suggest the dollar returns from FHB management practices depend on the interaction among biological and economic factors. Prior research has shown negative statistical relationships between FHB and wheat yield [8,12,13], however, damage from FHB is not always readily apparent i...

Fusarium Head Blight on Wheat: Biology, Modern Detection and Diagnosis and Integrated Disease Management

“…This practice prohibits perithecia formation and ascospore discharge during wheat spike development [ 21 , 125 ]. Another practice to reduce inoculum pressure is avoiding FHB cultural hosts, e.g., maize as a previous crop in wheat fields [ 126 ].…”

Methods for suppressing Fusarium infection during malting and their effect on malt quality

“…F. culmorum and F. avenaceum were observed to cause significant yield reductions, with F. avenaceum leading to smaller ear sizes, while F. graminearum was associated with decreased grain quality and toxin contamination rather than with yield reduction, with it producing most of the DON in barley (Linkmeyer et al 2016;Polišenská et al 2019;Timmusk et al 2020). Apart from the reduction of crop yield, fungal contamination in the field results in barley that falls below quality standards, significantly reducing prices due to downgrading use for feeds or outright rejection of the grains for use (McKee et al 2019).…”

“…This lead to significant price reductions due to the high mycotoxin levels and gushing, making them unsuitable for brewing. That results to downgrading the product as feeds or outright rejection of the grains for use (McKee et al 2019). Reduced grain plumpness and germination capacity due to FHB limit malting and brewing applications, leading to negative economic consequences (Nielsen et al 2014).…”