2006/03/27 by Wuletaw Tadesse, Sai L.K. Hsam, S. L. K. Hsam +2 · 12 citations
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · #Wheat and Barley Genetics and Pathology #Plant Disease Resistance and Genetics #Genetic Mapping and Diversity in Plants and Animals
paper · doi:10.2135/cropsci2005.10-0396
ABSTRACT Tan spot, caused by the fungus Pyrenophora tritici‐repentis (Died.) Drechs. ( Ptr ), anamorph Drechslera tritici‐repentis (Died.) Shoem., is becoming a major yield limiting leaf disease of both durum ( Triticum turgidum L. var durum) and common wheat ( Triticum aestivum L.) worldwide. In this study, differential isolates and varieties were developed, and using the most virulent isolate, ASC1b, we screened about 100 synthetic wheat genotypes against the disease. Two (2%) and 20 (20.4%) of the genotypes were found to be immune and highly resistant, respectively. Monosomic analyses of the F 2 hybrids (crosses of the highly resistant accessions (XX41, XX45) and the moderately resistant accession XX110 with the monosomic lines (D‐genome) of the wheat cultivar Chinese Spring have revealed that the resistance genes are located on chromosome 3D. The gene in lines XX41 and XX110 showed a recessive monogenic inheritance, whereas the gene in line XX45 exhibited a dominant mode of inheritance. The recessive genes from XX41 and XX110 are tentatively named tsn 3 and tsn‐syn1 , respectively, and the dominant gene from XX45 is named as Tsn‐syn2 .