Comparison of spring barley (Hordeum vulgare L.) screening methods for Fusarium head blight resistance breeding

Abstract

Fusarium head blight (FHB) is a widespread disease of cereals, includingbarley (Hordeum vulgare L.), that causes substantial grain yield lossesand grain quality deterioration. Resistant varieties provide thegreatest potential for reducing FHB. In the present study, we adaptedtwo methods for screening FHB severity using Fusarium culmorum. We useda cut-spike method and a spray inoculation method in the fieldconditions for screening different spring barley genotypes of Latvianand foreign origin. Screening with the cut-spike method was done for 126different genotypes in 2008 and in 2009 and for 180 genotypes in 2010.In the years 2011 and 2012, the field inoculation method was used toscreen 207 and 164 genotypes, respectively; part of material was testedsimultaneously by both methods. A significant effect of genotype wasfound for both cut-spike and field inoculation methods (p < 0.001);field inoculation method showed a greater proportion of genotype effectand a higher heritability. Using area under the disease progress curve(AUDPC) and score obtained at 26 days after inoculation were equallyeffective. Correlations between results obtained by both methods indifferent years were not significant, though, the data of the same yearcorrelated significantly (r = 0.36-0.47, p < 0.05). Results suggest thatdifferences between breeding material can be assessed by both methods;however, the information obtained was contradictory for a number ofgenotypes. Considering the results and the fact that field inoculationmethod can more likely provide results of equal value to those innatural conditions in respect to identification of resistant andsusceptible genotypes, field inoculation method was recognized aspreferable for the assessment of spring barley breeding material.Significant correlation (r = 0.71, p < 0.05) between visual estimate ofdisease severity and mycotoxin deoxynivalenol (DON) concentration ingrain was found in 2011, but in the environmental conditions of 2012formation of DON was inhibited.