Genetic analysis and fine mapping of LH1 and LH2, a set of complementary genes controlling late heading in rice (Oryza sativa L.).
Heading date in rice (Oryza sativa L.) is a critical agronomic trait with a complex inheritance. To investigate the genetic basis and mechanism of gene interaction in heading date, we conducted genetic analysis on segregation populations derived from crosses among the indica cultivars Bo B, Yuefeng B and Baoxuan 2. A set of dominant complementary genes controlling late heading, designated LH1 and LH2, were detected by molecular marker mapping. Genetic analysis revealed that Baoxuan 2 contains both dominant genes, while Bo B and Yuefeng B each possess either LH1 or LH2. Using larger populations with segregant ratios of 3 : 1, we fine-mapped LH1 to a 63-kb region near the centromere of chromosome 7 flanked by markers RM5436 and RM8034, and LH2 to a 177-kb region on the short arm of chromosome 8 between flanking markers Indel22468-3 and RM25. Some candidate genes were identified through sequencing of Bo B and Yuefeng B in these target regions. Our work provides a solid foundation for further study on gene interaction in heading date and has application in marker-assisted breeding of photosensitive hybrid rice in China.
State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University , Shanghai 200433, China.
Shuang
S
Liu
Feng
F
Wang
Li Jun
LJ
Gao
Jin Hua
JH
Li
Rong Bai
RB
Li
Han Liang
HL
Gao
Guo Fu
GF
Deng
Jin Shui
JS
Yang
Xiao Jin
XJ
Luo
complementary genes; fine mapping; gene interaction; heading date; rice (Oryza sativa L.)