Molecular cytogenetic characteristics of a translocation line between common wheat and Thinopyrum intermedium with resistance to powdery mildew

• Published in: Euphytica Vol. 197; no. 2; pp. 201 - 210
• Main Authors: Tang, Xueqin, Shi, Dong, Xu, Jie, Li, Yinglu, Li, Wenjing, Ren, Zhenglong, Fu, Tihua
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.05.2014; Springer; Springer Nature B.V
• Subjects: Agronomy. Soil science and plant productions; Airborne microorganisms; Analysis; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Blumeria graminis; Chromatin; Chromosomes; Cytogenetics; Fundamental and applied biological sciences. Psychology; Generalities. Genetics. Plant material; Genes; Genetics and breeding of economic plants; Genomics; Hybridization; Life Sciences; Pest resistance; Phenotypes; Plant breeding; Plant diseases; Plant Genetics and Genomics; Plant pathogens; Plant Pathology; Plant Physiology; Plant resistance; Plant Sciences; Selective breeding; Thinopyrum intermedium; Translocation; Triticum aestivum; Varietal selection. Specialized plant breeding, plant breeding aims; Wheat; Sequential C-banding-GISH; Double translocation; Powdery mildew resistance; ISH; Translocation; Monocotyledones; Agropyron intermedium; Mycosis; Translocation line; Cereal crop; Fungus resistance; Infection; Molecular parameter; Sequential; Gramineae; Thinopyrum intermedium; Angiospermae; Genetic improvement; Fluorescence in situ hybridization; Cytogenetics; Spermatophyta; Fodder crop; Molecular biology; Triticum aestivum
• ISSN: 0014-2336; 1573-5060
• DOI: 10.1007/s10681-013-1059-z

Powdery mildew caused by Blumeria graminis (DC) Speer f. sp. tritici Em. Marchal is a serious disease of wheat ( Triticum aestivum L.) in Southwestern China. A line of common wheat designated 08-723 isolated from the progeny of a hybrid between common wheat and Thinopyrum intermedium (Host) Barkworth & Dewey, was highly resistant to the existing powdery mildew races in the region. This line had a similar phenotype to its wheat parent, and it showed normal bivalent pairing at metaphase I of meiosis. It was analyzed by genomic in situ hybridization, fluorescence in situ hybridization and sequential C-banding-GISH to determine the amount, location and origin of the alien chromatin present. The results revealed that line 08-723 is homozygous for a two-point translocation replacing chromosome 6A of wheat. The translocation chromosome appears to have a normal 6AL arm; its short arm has a short terminal segment of ca. 10 % in length originating from an unidentified B-genome chromosome of wheat and a long proximal segment of ca. 90 % of the arms’ length originating from one of the St-genome chromosomes of Th. intermedium . Genetic analysis of powdery mildew resistance in F 1 , F 2 and F 2:3 populations from a cross of 08-723 with a susceptible wheat line indicated that the resistance was controlled by a single dominant gene and in a sample of F2 plants it always associated with the translocated chromosome. The gene responsible for resistance on the translocated chromosome may provide an alternate source of resistance in wheat breeding programs.