Comparison of evaluation methods for selection of resistance to Fusarium head blight in a recurrent selection programme in wheat (Triticum aestivum L.)

Abstract

AbstractThe objectives of this study were to compare efficiency of evaluation for resistance to Fusarium head blight (FHB) under two inoculation methods in a recurrent selection programme. Fifty selected homozygous F5 fertile lines, from each of five cycles (C0, C1, C2, C3 and C4) of recurrent selection, and two control cultivars were evaluated in a split‐plot design in 1995 and 1996 under the soil‐surface inoculation with Fusarium graminearum‐colonized kernels and the single‐floret inoculation with ascospore suspension. Comparison of the two inoculation methods using means, ranges, coefficients of variation, heritabilities and correlations among infected spikelet rate (ISR), reaction index (RI) and disease index (DI) indicated that FHB resistance could be evaluated with similar accuracy and precision using either of the two inoculation methods. Regressions of disease scores in the soil‐surface inoculation on disease scores in the single‐surface inoculation were positive and highly significant, showing a strong relationship between both inoculation methods for FHB resistance. The percentage of lines with similar performance for FHB disease scores in both inoculation methods was high. The soil‐surface inoculation and single‐floret inoculation appear to be useful techniques for evaluating numerous individuals of segregating population and screening advanced homozygous lines for FHB resistance in a recurrent selection programme in wheat, respectively.