RICE SCIENCE ›› 2009, Vol. 16 ›› Issue (3): 173-180 .DOI: 10.1016/S1672-6308(08)60076-1

• Research Paper • Previous Articles     Next Articles

Genetic Control of Germination Ability under Cold Stress in Rice

WANG Zhou-fei1; WANG Jian-fei1; WANG Fu-hua1, 2; BAO Yong-mei1; WU Yun-yu1; ZHANG Hong-sheng1   

  1. 1 State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China; 2 Institute of Crop Science, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
  • Received:2009-04-15 Online:2009-09-28 Published:2009-09-28
  • Contact: ZHANG Hong-sheng
  • Supported by:
    the Jiangsu Agricultural Three-Area-Focused Program, China (Grant No. Q200670), and the Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT), China.

Abstract: An F9 recombinant inbred lines (RIL) population, derived from a cross between IR28 (Oryza sativa L. spp. indica) and Daguandao (O. sativa L. spp. japonica), was used to construct a molecular linkage map and to identify germination ability including the traits of imbibition rate, germination rate, germination index, root length, shoot length and seed vigor at 14°C for 23 d. A composite interval mapping approach was applied to conduct genetic analysis for germination ability. The frequency distributions of the germination ability traits under the cold stress in the RIL population showed continuous segregation, suggesting they were quantitative traits controlled by several genes. A total of seven QTLs were identified on chromosomes 4, 6 and 9, including two for imbibition rate (qIR-6, qIR-9), one for germination rate (qGR-4), two for germination index (qGI-4-1, qGI-4-2) and two for root length (qRL-4-1, qRL-4-2). There were no detected QTLs controlling shoot length and seed vigor. The phenotypic variance explained by a single QTL ranged from 9.1% to 37.0%, and two major QTLs, qIR-6 and qGI-4-2, accounted for over 30% of the phenotypic variance. The expressions of QTLs were developmentally regulated and growth stage-specific. Most of the QTLs observed here were located in the regions similar to the QTLs for rice cold tolerance reported previously, indicating that these QTLs were reliable. However, qRL-4-2 is not reported before.

Key words: rice, cold stress, germination ability, quantitative trait locus