RRC ID 1701
Author Gu XY, Kianian SF, Foley ME.
Title Multiple loci and epistases control genetic variation for seed dormancy in weedy rice (Oryza sativa).
Journal Genetics
Abstract Weedy rice has much stronger seed dormancy than cultivated rice. A wild-like weedy strain SS18-2 was selected to investigate the genetic architecture underlying seed dormancy, a critical adaptive trait in plants. A framework genetic map covering the rice genome was constructed on the basis of 156 BC(1) [EM93-1 (nondormant breeding line)//EM93-1/SS18-2] individuals. The mapping population was replicated using a split-tiller technique to control and better estimate the environmental variation. Dormancy was determined by germination of seeds after 1, 11, and 21 days of after-ripening (DAR). Six dormancy QTL, designated as qSD(S)-4, -6, -7-1, -7-2, -8, and -12, were identified. The locus qSD(S)-7-1 was tightly linked to the red pericarp color gene Rc. A QTL x DAR interaction was detected for qSD(S)-12, the locus with the largest main effect at 1, 11, and 21 DAR (R(2) = 0.14, 0.24, and 0.20, respectively). Two, three, and four orders of epistases were detected with four, six, and six QTL, respectively. The higher-order epistases strongly suggest the presence of genetically complex networks in the regulation of variation for seed dormancy in natural populations and make it critical to select for a favorable combination of alleles at multiple loci in positional cloning of a target dormancy gene.
Volume 166(3)
Pages 1503-16
Published 2004-3
PII 166/3/1503
PMID 15082564
PMC PMC1470771
MeSH Alleles Chromosome Mapping Chromosomes, Plant Epistasis, Genetic* Genetic Linkage Genetic Variation* Genome, Plant Germination Oryza / genetics* Quantitative Trait Loci Seeds / genetics Seeds / physiology*
IF 4.075
Times Cited 93