@article{lauer_isik_2021, title={Major QTL confer race-nonspecific resistance in the co-evolved Cronartium quercuum f. sp. fusiforme-Pinus taeda pathosystem}, volume={6}, ISSN={["1365-2540"]}, url={https://doi.org/10.1038/s41437-021-00451-8}, DOI={10.1038/s41437-021-00451-8}, abstractNote={Fusiform rust disease, caused by the endemic fungus Cronartium quercuum f. sp. fusiforme, is the most damaging disease affecting economically important pine species in the southeast United States. Unlike the major epidemics of agricultural crops, the co-evolved pine-rust pathosystem is characterized by steady-state dynamics and high levels of genetic diversity within environments. This poses a unique challenge and opportunity for the deployment of large-effect resistance genes. We used trait dissection to study the genetic architecture of disease resistance in two P. taeda parents that showed high resistance across multiple environments. Two mapping populations (full-sib families), each with ~1000 progeny, were challenged with a complex inoculum consisting of 150 pathogen isolates. High-density linkage mapping revealed three major-effect QTL distributed on two linkage groups. All three QTL were validated using a population of 2057 cloned pine genotypes in a 6-year-old multi-environmental field trial. As a complement to the QTL mapping approach, bulked segregant RNAseq analysis revealed a small number of candidate nucleotide binding leucine-rich repeat genes harboring SNP associated with disease resistance. The results of this study show that in P. taeda, a small number of major QTL can provide effective resistance against genetically diverse mixtures of an endemic pathogen. These QTL vary in their impact on disease liability and exhibit additivity in combination.}, journal={HEREDITY}, publisher={Springer Science and Business Media LLC}, author={Lauer, Edwin and Isik, Fikret}, year={2021}, month={Jun} } @article{dewitt_guedira_lauer_sarinelli_tyagi_fu_hao_murphy_marshall_akhunova_et al._2020, title={Sequence-based mapping identifies a candidate transcription repressor underlying awn suppression at the B1 locus in wheat}, volume={225}, ISSN={["1469-8137"]}, DOI={10.1111/nph.16152}, abstractNote={Summary Awns are stiff, hair‐like structures which grow from the lemmas of wheat (Triticum aestivum) and other grasses that contribute to photosynthesis and play a role in seed dispersal. Variation in awn length in domesticated wheat is controlled primarily by three major genes, most commonly the dominant awn suppressor Tipped1 (B1). This study identifies a transcription repressor responsible for awn inhibition at the B1 locus. Association mapping was combined with analysis in biparental populations to delimit B1 to a distal region of 5AL colocalized with QTL for number of spikelets per spike, kernel weight, kernel length, and test weight. Fine‐mapping located B1 to a region containing only two predicted genes, including C2H2 zinc finger transcriptional repressor TraesCS5A02G542800 upregulated in developing spikes of awnless individuals. Deletions encompassing this candidate gene were present in awned mutants of an awnless wheat. Sequence polymorphisms in the B1 coding region were not observed in diverse wheat germplasm whereas a nearby polymorphism was highly predictive of awn suppression. Transcriptional repression by B1 is the major determinant of awn suppression in global wheat germplasm. It is associated with increased number of spikelets per spike and decreased kernel size.}, number={1}, journal={NEW PHYTOLOGIST}, author={DeWitt, Noah and Guedira, Mohammed and Lauer, Edwin and Sarinelli, Martin and Tyagi, Priyanka and Fu, Daolin and Hao, QunQun and Murphy, J. Paul and Marshall, David and Akhunova, Alina and et al.}, year={2020}, month={Jan}, pages={326–339} }