摘要
Two weak dormancy mutants, designated Q4359 and Q4646, were obtained from the rice cultivar N22 after treatment with 400 Gy 6Co gamma-radiation. Compared to the N22 cultivar, the dormancy of the mutant seeds was more readily broken when exposed to a period of room temperature storage. The mutants also showed a reduced level of sensitivity to abscisic acid compared to the N22 cultivar, although Q4359 was more insensitive than Q4646. A genetic analysis indicated that in both mutants, the reduced dormancy trait was caused by a single recessive allele of a nuclear gene, but that the mutated locus was different in each case. The results of quantitative trait locus （QTL） mapping, based on the F2 population from Q4359 x Nanjing35, suggested that Q4359 lacks the QTL qSdn-1 and carries a novel allele at QTL qSdn-9, while a similar analysis of the Q4646 x Nanjing35 F2 population suggested that Q4646 lacks QTL qSdn-5, both qSdn-1 and qSdn-5 are major effect seed dormancy QTL in N22. Therefore, these two mutants were helpful to understand the mechanism of seed dormancy in N22.
Two weak dormancy mutants, designated Q4359 and Q4646, were obtained from the rice cultivar N22 after treatment with 400 Gy 6Co gamma-radiation. Compared to the N22 cultivar, the dormancy of the mutant seeds was more readily broken when exposed to a period of room temperature storage. The mutants also showed a reduced level of sensitivity to abscisic acid compared to the N22 cultivar, although Q4359 was more insensitive than Q4646. A genetic analysis indicated that in both mutants, the reduced dormancy trait was caused by a single recessive allele of a nuclear gene, but that the mutated locus was different in each case. The results of quantitative trait locus （QTL） mapping, based on the F2 population from Q4359 x Nanjing35, suggested that Q4359 lacks the QTL qSdn-1 and carries a novel allele at QTL qSdn-9, while a similar analysis of the Q4646 x Nanjing35 F2 population suggested that Q4646 lacks QTL qSdn-5, both qSdn-1 and qSdn-5 are major effect seed dormancy QTL in N22. Therefore, these two mutants were helpful to understand the mechanism of seed dormancy in N22.
基金
supported by grants from the National Natural Science Foundation of China(30471120,30671246)
the High-tech Research and Development(863)Program(projects 2009AA101101)of China
National Key Transform Program (2008ZX08001-06)
the Jiangsu Cultivar Development Program (projects BE2009301-3 and BE2008354)
the 111 Project (B08025)
