title: Fine Mapping Identifies a New QTL for Brown Rice Rate in Rice (Oryza Sativa L.).
abstract: BACKGROUND
  High yield and quality determine the commercial potential of rice variety. Brown rice rate (BRR) is a key factor ensuring grain yield and quality in rice. So far, there were few reports about the genes that directly controlled the BRR in rice. Therefore, dissecting the genetic mechanism of the BRR genes can facilitate improving effective rice supply or edible grain yield.
  
  
  RESULTS
  A double haploid population derived from the cross between Taichung Native 1 (TN1) (an indica variety) and Chunjiang 06 (CJ06) (a japonica variety) was used to investigate the genetic basis of grain milling and appearance traits affecting the BRR. By using a constructed molecular linkage map, four quantitative trait loci (QTLs) for the BRR were detected on chromosomes 1, 8, 9, and 10, respectively. In addition, three QTLs for appearance traits, including grain weight and grain length/width ratio, were detected on chromosomes 6, 9 and 10, respectively. Chromosome segment substitution lines (CSSLs) were established at the qBRR-10 locus. Finally, the qBRR-10 was narrowed to a 39.5 kb region on chromosome 10. In this region, two candidate genes, LOC_Os10g32124 and LOC_Os10g32190, showed significantly differential expression in TN1 and CSSL1-2 compared with CJ06. Histocytological analysis suggested that cell size and hull thickness may be important factors for the BRR.
  
  
  CONCLUSIONS
  In the study, the qBRR-10 affected the BRR and was finally located to a region between two markers, P13 and P14. Two candidate genes were selected based on the expression difference between two parents, which facilitated the further cloning of the qBRR-10 gene and largely contributed to improve the grain yield and quality in rice.
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China.
authors: Deyong
authors: D
authors: Ren
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China.|College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, 321004, P. R. China.
authors: Yuchun
authors: Y
authors: Rao
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China.
authors: Lichao
authors: L
authors: Huang
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China.
authors: Yujia
authors: Y
authors: Leng
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China.
authors: Jiang
authors: J
authors: Hu
authors: College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, 321004, P. R. China.
authors: Mei
authors: M
authors: Lu
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China.
authors: Guangheng
authors: G
authors: Zhang
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China.
authors: Li
authors: L
authors: Zhu
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China.
authors: Zhenyu
authors: Z
authors: Gao
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China.
authors: Guojun
authors: G
authors: Dong
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China.
authors: Longbiao
authors: L
authors: Guo
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China. qianqian188@hotmail.com.
authors: Qian
authors: Q
authors: Qian
authors: State Key Lab for Rice Biology, China National Rice Research Institute, Hangzhou, 310006, P. R. China. dalizeng@126.com.
authors: Dali
authors: D
authors: Zeng
keywords: Brown rice ate; Candidate genes; Fine mapping; Histocytological analysis; QTLs