Conditional and unconditional mapping of quantitative trait loci underlying plant height and tiller number in rice (Oryz

In this study,we used 127 double haploid (DH) lines to analyze agricultural traits of rice.The DH lines,derived from a ZYQ8 (indica)/JX17 (japonica) cross by anther culture,contained 160 RFLP and 83 SSR markers.Unconditional and conditional quantitative trait loci (QTL) mapping was conducted to analyze plant height (PH) and tillers per plant (TP) at five growth stages that were grown at two nitrogen levels.Fourteen PH and 13 TP unconditional QTL were identified in the different growth stages,including 19 QTL from high-nitrogen (HN) and 14 QTL from low-nitrogen (LN) conditions.The conditional QTL for 14 genomic regions under LN/HN con-ditions showed that there was a significant effect on PH and TP across the different stages.Only one conditional QTL,ph2-3,was unable to be detected in unconditional mapping.More QTL were detected in the first four rice growth stages than in the final stage.Further-more,a line from the DH mapping population,DH78,was identified in extreme phenotypes of PH and TP that exhibited dwarfism and less-tiller (dft) characters.The gene dftl was mapped to chromosome 2 using a backcrossed population of DH78/JX17 through a map-based cloning strategy.The location of dftl coincided with the mapping region of the small-LOD peak,QTL ph2 and tp2,which were identified in plants grown in low-nitrogen conditions.Further backcrossing and fine-mapping successfully delimited the dftl locus to a 91 kb region.

作 者： Hua Jiang Liang Jiang Longbiao Guo Zhenyu Gao Dali Zeng Lihuang Zhu Guohua Liang Qian Qian   作者單位： Hua Jiang(State Key Laboratory of Rice BiologylKey Laboratory of Plant Functional Genomics, Ministry of Education of China,Yangzhou University, Yangzhou 225009, China;State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, China)

Liang Jiang,Longbiao Guo,Zhenyu Gao,Dali Zeng,Qian Qian(State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, China)

Lihuang Zhu(Institute of Genetics, Chinese Academy of Sciences, Beijing 100101, China)

Guohua Liang(State Key Laboratory of Rice BiologylKey Laboratory of Plant Functional Genomics, Ministry of Education of China,Yangzhou University, Yangzhou 225009, China) 

刊 名： 自然科學進展（英文版）  SCI 英文刊名： PROGRESS IN NATURAL SCIENCE  年，卷(期)： 2008 18(12)  分類號： N1  關鍵詞： Oryza sativa   Quantitative trait loci   Double haploid (DH) population   Developmental behavior   Nitrogen   Map-based cloning