Testing transgenic spring wheat and barley lines for reaction to fusarium head blight: 2018 field nursery report.

Authors: DILL-MACKEY, RUTH - University Of Minnesota; ELLAKAD, AMAR - University Of Minnesota; ZARGARAN, BEHESHTEH - University Of Minnesota; MUEHLBAUER, GARY - University Of Minnesota; BETHKE, GERIT - University Of Minnesota; MCLAUGHLIN, JOHN - Rutgers University; TUMER, NILGEN - Rutgers University; Funnell-Harris, Deanna

Submitted to: National Fusarium Head Blight Forum
Publication Type: Abstract Only
Publication Acceptance Date: 12/3/2018
Publication Date: 12/4/2018
Citation: Dill-Mackey, R., Ellakad, A.M., Zargaran, B., Muehlbauer, G.J., Bethke, G., Mclaughlin, J., Tumer, N., Funnell-Harris, D.L. 2018. Testing transgenic spring wheat and barley lines for reaction to fusarium head blight: 2018 field nursery report.. National Fusarium Head Blight Forum Proceedings. p.70

Interpretive Summary:

Technical Abstract: The 2018 field screening nursery consisted of 98 wheat and 15 barley entries evaluated in adjacent experiments. Entries within each experiment were arranged in a randomized complete block design with four replications in a field located at UMore Park, Rosemount MN. Trial entries and untransformed parental controls* were submitted by the University of Minnesota (46 wheat lines + Rollag* and Linkert*; 13 barley lines + Rasmusson*), Rutgers University (16 wheat lines + RB07* and Bobwhite) and the USDA (8 wheat lines + CB037*). Lines with known reactions to Fusarium head blight (FHB) were also included as checks. The wheat checks included were the moderately resistant cultivars Rollag and Sumai 3 and the susceptible cultivars Norm and Wheaton. The barley checks were the moderately resistant cultivar Quest and the susceptible cultivar Rasmusson. Individual plots were 2.43 m long single rows. The trial was planted on May 22, 2018. All plots were inoculated twice. The first inoculation was applied at anthesis for wheat (July 2) and at head emergence (July 10) for barley. The second inoculation was applied three days after the initial inoculation (d.a.i.) for each plot with the last inoculations conducted on July 20. The inoculum was a composite of 26 F. graminearum isolates, applied at a concentration of 100,000 macroconidia.ml-1 with Tween 20 (polysorbate) added at 2.5 ml.L-1 as a wetting agent. The inoculum was applied using a CO2-powered backpack sprayer fitted with a SS8003 TeeJet spray nozzle with an output of 10 ml.sec-1 at a working pressure of 275 kPa. Mist-irrigation was applied from the first inoculation on July 2 through July 27 to facilitate FHB development. FHB incidence and severity were assessed visually 20-24 d.a.i. for wheat and 13-14 d.a.i. for barley on 20 arbitrarily selected heads per plot. FHB incidence was determined by the percentage of spikes with visually symptomatic spikelets of the 20 heads observed. FHB severity was determined as the percentage symptomatic spikelets of the total of all spikelets observed. Plots were hand harvested at maturity on August 13 and 14. Approximately sixty heads where harvested from each plot, threshed and the seed cleaned manually. The wheat grain was used to determine the percentage of visually scabby kernels (VSK) and then all samples (wheat and barley) were ground and submitted for deoxynivalenol (DON) analysis. Mean FHB severities for the untransformed parental wheat checks Bobwhite, CB037, Linkert, RB07, and Rollag were 22%, 36%, 6%, 11% and 9%, respectively. The mean FHB severity for the susceptible wheat checks Wheaton was 31%. The mean FHB severity for the untransformed parent barley check Rasmusson was 26% while the susceptible barley check Lacey had a mean FHB severity of 34% and the moderately resistant line Quest had an FHB severity of 13%. The FHB severity data indicated that resistance was improved in some transformed lines compared to the untransformed checks. The harvested grain is currently being analyzed for VSK and DON. The data are not yet available, although they will be included in the poster presented at the forum.