Fine mapping of a gene for non-pollen type thermosensitive genic male sterility in rice (Oryza sativa L.).
The thermo-sensitive genic male sterility (TGMS) lines play a crucial role in two-line hybrid rice production. For a practical TGMS line, the stability of male sterility is one of the most important technical indicators. In this study, XianS, a spontaneous mutant with stable male sterility from an indica rice cultivar Xianhuangzhan, was classified as a non-pollen type TGMS line. The critical non-pollen sterility point temperature of XianS was determined as 27 degrees C. Genetic analysis demonstrated that the non-pollen sterility in XianS was controlled by a single recessive gene. Using SSR markers and bulked segregant analysis, the TGMS gene in XianS was fine mapped to a 183 kb interval between RMAN81 and RMX21 on chromosome 2. Two markers, 4039-1 and RMX14 completely cosegregated with this gene. Allelism test indicated that the non-pollen phenotype in seven non-pollen type TGMS lines from different sources, XianS, AnnongS-1, Q523S, Q524S, N28S, G421S, and Q527S is caused by the same TGMS gene. Although the location of TGMS gene in XianS is close to the gene OsNAC6, a previously identified candidate gene of tms5 in AnnongS-1, the sequence of OsNAC6 and its promoter region was identical in TGMS line XianS, AnnongS-1, and wild-type Xianhuangzhan. These results suggest that the non-pollen type TGMS trait probably be controlled by the same TGMS gene in different TGMS rice lines, but its real candidate gene still need to be further studied and identified.
Peng
H F
HF
College of Life Science, South China Agricultural University, 510642, Guangzhou, China. phf72@scau.edu.cn
Chen
X H
XH
Lu
Y P
YP
Peng
Y F
YF
Wan
B H
BH
Chen
N D
ND
Wu
B
B
Xin
S P
SP
Zhang
G Q
GQ
D001483:Base Sequence; D002874:Chromosome Mapping; D018556:Crops, Agricultural / Q000235:genetics / Q000502:physiology; D003433:Crosses, Genetic; D017343:Genes, Plant; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics* / Q000502:physiology; D010641:Phenotype; D051479:Plant Infertility / Q000235:genetics*; D011058:Pollen / Q000235:genetics*; D017422:Sequence Analysis, DNA