QTLs of Cold Tolerance-Related Traits at the Booting Stage for NIL-RILs in Rice Revealed by SSR

• Published in: Genes & genomics Vol. 31; no. 2; pp. 143 - 154
• Main Authors: Ya Wen Zeng, Shu Ming Yang, Hong Cui, Xiao Juan Yang, Li Ming Xu, Juan Du, Xiao Ying Pu, Zi Chao Li, Zai Quan Cheng, Xing Qi Huang
• Format: Journal Article
• Language: Korean
• Published: 한국유전학회 30.04.2009
• Subjects: cold tolerance-related traits; near-isogenic Line at booting stage; QTL; quantitative trait Loci; rice (Oryza sativa L.)
• ISSN: 1976-9571; 2092-9293

QTLs for cold tolerance-related traits at the booting stage using balanced population for 1525 recombinant inbred lines of near-isogenic lines (viz. NIL-RILs for BC5F3 and BC5F4 and BC5F5) over 3 years and two locations by backcrossing the strongly cold-tolerant landrace (Kunmingxiaobaigu) and a cold-sensitive cultivar (Towada) was analyzed. In this study, 676 microsatellite markers were employed to identify QTLs conferring cold tolerance at booting stage. Single marker analysis revealed that 12 markers associated with cold tolerance on chromosome 1, 4 and 5. Using a LOD significance threshold of 3.0, compositive interval mapping based on a mixed linear model revealed eight QTLs for 10 cold tolerance-related traits on chromosomes 1, 4, and 5. They were tentatively designated qCTB-1-1, qCTB-4-1, qCTB-4-2, qCTB-4-3, qCTB-4-4, qCTB-4-5, qCTB-4-6, and qCTB-5-1. The marker intervals of them were narrowed to 0.3-6.8 cM. Genetic distances between the peaks of the QTL and nearest markers varied from 0 to 0.04 cM. We were noticed in some traits associated cold tolerance, such as qCTB-1-1 for 5 traits (plant height, panicle exsertion, spike length, blighted grains per spike and spikelet fertility), qCTB-4-1 for 8 traits (plant height, node length under spike, leaf length, leaf width, spike length, full grains per spike, total grains per spike and spikelet fertility), qCTB-4-2 for 3 traits (spike length, full grains per spike and spikelet fertility), qCTB-5-1 for 5 traits (plant height, panicle exsertion, blighted grains per spike, full grains per spike and spikelet fertility). The variance explained by a single QTL ranged from 0.80 to 16.80%. Three QTLs (qCTB-1-1, qCTB-4-1, qCTB-4-2) were detected in two or more trials. Our study sets a foundation for cloning cold-tolerance genes and provides opportunities to understand the mechanism of cold tolerance at the booting stage.