International Journal of Molecular Sciences Article The Resistance of Narrow-Leafed Lupin to Diaporthe toxica Is Based on the Rapid Activation of Defense Response Genes Michał Ksi ˛azkiewicz˙ 1,* , Sandra Rychel-Bielska 1,2 , Piotr Plewi ´nski 1 , Maria Nuc 3 , Witold Irzykowski 4 , Małgorzata J˛edryczka 4 and Paweł Krajewski 3 1 Department of Genomics, Institute of Plant Genetics, Polish Academy of Sciences, 60-479 Pozna´n,Poland;
[email protected] (S.R.-B.);
[email protected] (P.P.) 2 Department of Genetics, Plant Breeding and Seed Production, Wroclaw University of Environmental and Life Sciences, 50-363 Wrocław, Poland 3 Department of Biometry and Bioinformatics, Institute of Plant Genetics, Polish Academy of Sciences, 60-479 Pozna´n,Poland;
[email protected] (M.N.);
[email protected] (P.K.) 4 Department of Pathogen Genetics and Plant Resistance, Institute of Plant Genetics, Polish Academy of Sciences, 60-479 Pozna´n,Poland;
[email protected] (W.I.);
[email protected] (M.J.) * Correspondence:
[email protected]; Tel.: +48-616-550-268 Abstract: Narrow-leafed lupin (Lupinus angustifolius L.) is a grain legume crop that is advantageous in animal nutrition due to its high protein content; however, livestock grazing on stubble may develop a lupinosis disease that is related to toxins produced by a pathogenic fungus, Diaporthe toxica. Two major unlinked alleles, Phr1 and PhtjR, confer L. angustifolius resistance to this fungus. Besides the introduction of these alleles into modern cultivars, the molecular mechanisms underlying resistance remained unsolved. In this study, resistant and susceptible lines were subjected to differential gene expression profiling in response to D.