Transcript profiling of Lr1- and Lr34-mediated leaf rust resistance in wheat

The wheat gene Lr34 confers partial resistance to all races of Puccinia triticina, the causal agent of wheat leaf rust. However, the biological basis for the exceptional durability of Lr34 is unclear. The Affymetrix wheat genome array was used to identify wheat genes differentially expressed in a compatible interaction (Tc), an R-gene mediated incompatible interaction (Tc-Lr1), and a race non-specific resistance interaction (Tc-Lr34) in response to infection challenge by P. triticina race 1 at anthesis. Transcriptome interrogation was conducted by comparing mock- and P. triticina-inoculated leaves harvested at 3 and 7 days post inoculation (dpi). Keywords: Time course Overall design: The Affymetrix wheat genome array was used to identify wheat genes differentially expressed in a compatible interaction (Tc), an R-gene mediated incompatible interaction (Tc-Lr1), and a race non-specific resistance interaction (Tc-Lr34) in response to infection challenge by P. triticina race 1 at anthesis. Transcriptome interrogation was conducted on leaves harvested at 3 and 7 days post inoculation (dpi). The study utilized a randomized complete block design with three replicates for each genotype, and employed univariate analysis (t-tests) between mock- and P. triticina-inoculated plants within each genotype at each timepoint, for a total of six comparisons across the entire experiment, utilizing a total 36 Affymetrix Wheat Genome Array GeneChips.