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Abstract Background and ObjectivesFlour quality is a key target of hard winter wheat breeding. The Farinograph is important for assessing quality before cultivar release in the United States, but large sample size requirements and long test times render it impractical for early‐stage selection relative to the GlutoPeak. To improve GlutoPeak utility for breeding, we calculated new parameters from device raw output and used random forest regression to predict key Farinograph parameters in a winter wheat population containing wild relative introgressions. FindingsThe key quality parameters of absorption, bake absorption, tolerance stability, and mixing tolerance index were moderately well predicted (R²ranging from 0.488 to 0.745). Classification of samples as acceptable or unacceptable for mixing tolerance index and tolerance stability was more accurate than prediction of numeric values. ConclusionsNew features calculated from the GlutoPeak raw data were useful predictors of quality. Prediction accuracies are sufficient to improve breeding populations. Significance and NoveltyThis study is the first to use wheat wild relative introgressions in GlutoPeak Farinograph prediction, the first to generate features from raw data, and is one of the few random forest models for quality prediction. The tools that we provide will improve ability to cull poor‐quality lines early in the breeding pipeline can support efficient wheat cultivar development. 

Abstract BACKGROUNDThe wheat stem sawfly (WSS,Cephus cinctus) is a major pest of wheat (Triticum aestivum) and can cause significant yield losses. WSS damage results from stem boring and/or cutting, leading to the lodging of wheat plants. Although solid‐stem wheat genotypes can effectively reduce larval survival, they may have lower yields than hollow‐stem genotypes and show inconsistent solidness expression. Because of limited resistance sources to WSS, evaluating diverse wheat germplasm for novel resistance genes is crucial. We evaluated 91 accessions across five wild wheat species (Triticum monococcum,T. urartu,T. turgidum,T. timopheevii, andAegilops tauschii) and common wheat cultivars (T. aestivum) for antixenosis (host selection) and antibiosis (host suitability) to WSS. Host selection was measured as the number of eggs after adult oviposition, and host suitability was determined by examining the presence or absence of larval infestation within the stem. The plants were grown in the greenhouse and brought to the field for WSS infestation. In addition, a phylogenetic analysis was performed to determine the relationship between the WSS traits and phylogenetic clustering. RESULTSOverall,Ae. tauschii,T. turgidumandT. urartuhad lower egg counts and larval infestation thanT. monococcum, andT. timopheevii.T. monococcum,T. timopheevii,T. turgidum, andT. urartuhad lower larval weights compared withT. aestivum. CONCLUSIONThis study shows that wild relatives of wheat could be a valuable source of alleles for enhancing resistance to WSS and identifies specific germplasm resources that may be useful for breeding. © 2024 The Authors.Pest Management Sciencepublished by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 

Abstract The wheat wild relativeAegilops tauschiiwas previously used to transfer theLr42leaf rust resistance gene into bread wheat.Lr42confers resistance at both seedling and adult stages, and it is broadly effective against all leaf rust races tested to date.Lr42has been used extensively in the CIMMYT international wheat breeding program with resulting cultivars deployed in several countries. Here, using a bulked segregant RNA-Seq (BSR-Seq) mapping strategy, we identify three candidate genes forLr42. Overexpression of a nucleotide-binding site leucine-rich repeat (NLR) gene AET1Gv20040300 induces strong resistance to leaf rust in wheat and a mutation of the gene disrupted the resistance. TheLr42resistance allele is rare inAe. tauschiiand likely arose from ectopic recombination. Cloning ofLr42provides diagnostic markers and over 1000 CIMMYT wheat lines carryingLr42have been developed documenting its widespread use and impact in crop improvement.