A major concern with barley infected
with Fusarium graminearum is the accumulation of the mycotoxin
deoxynivalenol (DON). The hull of barley can account for a significant amount
of the DON in Fusarium infected grain. Nearly all the barley in the U.S. is
covered barley used for animal feed or by the malting and brewing industries. Loss
of the hull during harvest as occurs with naked barley could be a way to
mitigate the risk of DON contamination in the food chain. To explore this
potential benefit, we developed near-isogenic lines (NILs) for the hulless
trait. A total of 30 NILs for each class (naked and covered) were evaluated in an
inoculated Fusarium head blight (FHB) nursery in 2021. The average concentration
of the naked lines compared to the covered lines was 2.4 and 5.9, respectively.
This constitutes a 59 % reduction in the DON concentration of the harvested grain.
This reduction in DON is comparable to what is possible using a protective
fungicide or by using a moderately resistant cultivar versus a susceptible one.
It may also be possible to develop selection strategies that increase the
amount of DON that accumulates in the hull relative to the kernel further
reducing DON levels in the harvested naked grain. Breeding naked barley
varieties with reduced DON and that can have multiple end uses could have a
substantial impact on reducing the risk of DON contamination.