A collection of 433 Aegilops tauschii was screened for
response to infection with Stagonospora nodorum.
Resistance similar or marginally superior to the range observed in spring
wheat genotypes was readily identified. Three lines, RL5271, Aus18911, and
Aus21712, were resistant to a range of pathogen isolates and were similar in
resistance to a highly resistant French line, No.33. Accessions of
Ae. tauschii assessed as resistant or susceptible as
seedlings had corresponding reactions when tested as adult plants, with
resistance being commonly expressed as restricted lesion development.
Infection frequency differed between some Ae. tauschii
lines. Seedling resistance in synthetic bread wheats was expressed partially
or not at all depending on both the tetraploid and the
tetraploid/Ae. tauschii combination. Assessment of
adult responses among a range of synthetics showed occasional expression of
moderate resistance around the level observed among reference bread wheat
cultivars of similar maturity. Disease escape associated with late maturity
was common. One synthetic wheat, #231, derived from a resistant
Ae. tauschii, exhibited low adult disease expression
associated with late maturity. This line was resistant in seedling tests and
seedling resistance was dominant in F1 hybrids to bread
wheat.
Evaluation of synthetic wheat lines (Triticum durum/Aegilops tausсhii) for vegetative period and resistance to diseases
