Mapping quantitative trait loci controlling sheath blight resistance in two rice cultivars (Oryza sativa L.)

• Published in: Theoretical and applied genetics Vol. 101; no. 4; pp. 569 - 573
• Main Authors: ZOU, J. H, PAN, X. B, CHEN, Z. X, XU, J. Y, LU, J. F, ZHAI, W. X, ZHU, L. H
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.09.2000; Berlin Springer Nature B.V
• Subjects: Biological and medical sciences; chromosome 11; chromosome 2; chromosome 3; chromosome 7; chromosome 9; Chromosomes; Classical genetics, quantitative genetics, hybrids; Cultivars; Disease; Fundamental and applied biological sciences. Psychology; Fungi; Genetics of eukaryotes. Biological and molecular evolution; Oryza sativa; Pteridophyta, spermatophyta; Rice; Seeds; Vegetals; Genetic mapping; Monocotyledones; Plant pathogen; Quantitative character; Chromosome; Cereal crop; Fungus resistance; Fungi; Oryza sativa; Gramineae; Angiospermae; F2 hybrid; Rhizoctonia solani; Spermatophyta; Fungi Imperfecti; Clonal propagation; Thallophyta
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s001220051517

Rice sheath blight, caused by Rhizoctonia solani Kühn, is one of the three major diseases of rice. The present study was conducted with an F^sub 2^ clonal population of Jasmine 85/Lemont. The F^sub 2^ population, including 128 clonal families, was inoculated by short toothpicks incubated with a strain, RH-9 of the fungus. Based on field disease evaluations in 2 years and a genetic map with 118 evenly distributed molecular markers, we identified six quantitative trait loci (QTLs) contributing to sheath blight resistance. These QTLs, qSB-2, qSB-3, qSB-7, qSB-9-1, qSB-9-2 and qSB-11, were located on chromosomes 2, 3, 7, 9 and 11, respectively. The respective alleles of qSB-2, qSB-3, qSB-7, and qSB-9-2 from Jasmine 85 could explain 21.2%, 26.5%, 22.2% and 10.1% of the total phenotypic variation, respectively; while the alleles of qSB-9-1 and qSB-11 from Lemont could explain 9.8% and 31.2% of the total phenotypic variation. Of these qSB-2 and qSB-11 could be detected in both years, while remaining loci were detected only in a single year. Furthermore, four QTLs (qHD-2, qHD-3, qHD-5 and qHD-7) controlling heading date and three QTLs (qPH-3, qPH-4 and qPH-11) controlling plant height were also identified. Though rice sheath blight resistance may be influenced by morphological traits, such as heading date and plant height, in the present study most detected resistance loci were not linked to the loci for heading date or plant height.[PUBLICATION ABSTRACT]