Submitted to: National Fusarium Head Blight Forum Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 12/13/2010
Publication Date: 12/7/2010
Citation: Ng, E., Abebe, T., Jurgenson, J.E., Dill-Mackey, R., Dahleen, L.S., Skadsen, R.W. 2010. Greenhouse evaluation of transgenic barley expressing gastrodianin for resistance to Fusarium head blight. National Fusarium Head Blight Forum Proceedings. pg 28-32. Interpretive Summary:
Technical Abstract: The 2010 field screening nursery, with 88 barley plots was located at UMore Park, Rosemount MN. Trial entries (n=18) and an the untransformed 2-row control Conlon (susceptible) were submitted by USDA-ARS, RRVARC Fargo. Barley lines with known reactions to Fusarium head blight (FHB) were also included as checks. The checks used were the moderately resistant cultivar Quest (included in previous nurseries as breeding line number M122) and the susceptible cultivars Robust and Stander. The experimental design was a randomized block with four replicates. Plots were 2.4 m long single rows. The trial was planted on May 4, 2010. All plots were inoculated twice, with the first inoculation applied at head emergence. The second inoculation was applied three days after the initial inoculation (dai) for each plot. The inoculum was a composite of 51F. graminearum isolates at a concentration of 200,000 macroconidia.ml-1 with Tween 20 (polysorbate) added at 2.5 ml.L-1 as a wetting agent. The inoculum was applied at a rate of ca. 30 ml per meter of plot row. The inoculum was applied using a CO2-powered backpack sprayer fitted with a SS8003 TeeJet spray nozzle with an output of 10ml.sec-1 at a working pressure of 275 kPa. Mist-irrigation was applied from the first inoculation on June 28 till July 15 to facilitate FHB development. FHB incidence (FHBI) and severity (FHBS) were assessed visually 14 d.a.i. on 20 arbitrarily selected spikes per plot. FHBI was determined by the percentage of spikes with visually symptomatic spikelets of the 20 spikes observed. FHBS was determined as the percentage symptomatic spikelets of the total of all spikelets observed on the 20 spikes. Plots were harvested at maturity on August 5. The harvested seed from each plot was split to obtain a 25 g sub-sample, which was then cleaned by hand. The samples were ground and submitted for deoxynivalenol (DON) analysis. FHBI for all treatments ranged from 86 to 99% . FHBS ranged from 13 to 36% for the 18 entries examined. The FHBS for the untransformed control Conlon was 23%. The FHBS for the moderately resistant check Quest was 15% while FHBS for the susceptible checks Robust and Stander were 15% and 22%, respectively. The level of disease was similar to the 2009 nursery. We anticipate the DON data (not yet available) will provide additional information on the response of these entries to FHB.