Annual Progress Report on Malting Barley Research March, 2007

western Minnesota is consistent with that of a sexually reproducing fungus. This diversity
and likelihood of a sexual stage in S passerinii indicate that single dominant resistance
genes may have a limited life if employed widespread throughout the region. Consideration
should be given to pyramiding more than one of the genes into breeding material.
7. Control of FHB in Barley by reducing inoculum load of the pathogen. PhD Student
Scott Halley tested in the field at Langdon in 2006, 15 chemical treatments plus an
untreated control on Fusarium infested crop stubble for their ability to inhibit pathogen
sporulation and head blight disease. Sporulation was measured by bagging and exposing
barley heads for predetermined times and then washing and culturing to determine the
number of spores on the heads. Sporulation was also measured by placing volumetric
spore collectors and open Petri plates with selective isolation media under the barley
canopy. Due to the dry season little infection was seen and few spores were measured.
Experiments will have to be repeated in 2006 to obtain useful data.
In a second study undertaken with Mr. Halley, we investigated the effect of fungicide
application at different stages of tiller development in an attempt to explain the poor control
of FHB fungicides sprayed on barley compared to the control obtained on wheat. Tillers
that were spayed with fungicide at maturities earlier or later than that recommended
suggests that two-rowed and six-rowed barleys as well as hard red spring wheat may
benefit from additional fungicide applications to protect these tillers in some environments.
An application of tebuconazole fungicide only reduced FHB incidence at head fully
emerged growth stage but did not affect tillers that had not reached this growth stage. As
barley does not develop synchronously there is always a proportion of tillers at spraying
that are younger and older than the recommended age Deoxynivalenol concentrations
were reduced in one environment when the growth stages were head partially emerged
and head fully emerged but were not reduced by other growth stages.
Experiments are also continuing with Prof Nick Hill at the University of Georgia. We have
collected, purified and shipped several shipments of spores to Prof Hill to determine the
specificity of his ELISA method of Fusarium graminearum quantifications, the minimum
detection limits and the impact of method of shipment on sensitivity. All experiments are
ongoing.
OTHER FUNDS AND FUTURE DIRECTIONS
1. Common Root Rot Resistance Gene Mapping for Barley CAP
Research in 2006 was the first year of a four year project funded by the CSREES CAP
Barley project. Common root rot (CRR) caused by Bipolaris sorokiniana has been
identified as a disease of importance in barley in North Dakota and in adjacent Canadian
Provinces. Losses in yield average 5 to 15% and are more consistent than leaf diseases
that occur in epidemics. Canadian researchers have been breeding for resistance to CRR
and Canadian Pathologists have been supplying information to growers for more than 40
years so that they can manage the disease and use resistant cultivars. No information or
resistant lines are available in North Dakota.
We organized and took receipt of the subset of OPAH2 lines available in sufficient
quantities (about 500g) for large scale field trials for testing of disease reaction to common
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