Evaluation of Lithuanian winter wheat breeding lines for Bipolaris sorokiniana resistance by detached leaf technique

Abstract

The research was conducted at the Lithuanian Institute of Agriculture (LIA) during the period 2005–2008. Resistance of advanced winter wheat breeding lines to Bipolaris sorokiniana monoconidial isolates obtained from wheat straw and grain was evaluated under laboratory conditions using the detached leaf technique. A total of three checks with a known resistance level and 104 advanced breeding lines were investigated using four B. sorokiniana isolates. The screening technique used revealed a low resistance of the test material. The resistant cultivar BR8 and the moderately resistant cultivar BH1146 were found to be moderately susceptible (6.1 and 7.0 scores, respectively). The line ‘Zentos / Lut97-4’ was slightly more resistant (5.9 scores) than BR8 (6.1 scores). The ten lines possessed a resistance level similar to that of the cultivars BR8 and BH1146. The rest of the lines (79.4%) were susceptible or very susceptible. Analysis of the pedigree of the lines did not reveal any clear impact of parental cultivars on the resistance of lines. Only the line WW2498 conferred resistance as all the four breeding lines possessing it were given 6.8 to 7.0 scores. Pathogen isolates with a lower aggressiveness could be more adequate for testing low-resistant wheat. Keywords: Triticum aestivum, spot blotch, isolates, susceptibility