Genetic control of phenotypic plasticity in Asian cultivated and wild rice in response to nutrient and density changes.
Phenotypic plasticity is an adaptive mechanism adopted by plants in response to environmental heterogeneity. Cultivated and wild species adapt in contrasting environments; however, it is not well understood how genetic changes responsible for phenotypic plasticity were involved in crop evolution. We investigated the genetic control of phenotypic plasticity in Asian cultivated (Oryza sativa) and wild rice (O. rufipogon) under 5 environmental conditions (2 nutrient and 3 density levels). Quantitative trait locus (QTL) analysis was conducted for traits affecting plant architecture and biomass production. By analysing the phenotypic means, QTLs of large effects were detected as a cluster on chromosome 7 under all the environmental conditions investigated; this might have contributed to transitions of plant architecture during domestication, as reported previously. Multiple QTLs of plasticity were also found within this QTL cluster, demonstrating that allele-specific environmental sensitivity might control plasticity. Furthermore, QTLs controlling plasticity without affecting phenotypic means were also identified. The mode of action and direction of allele effects of plasticity QTLs varied depending on the traits and environmental signals. These findings confirmed that cultivated and wild rice show distinctive genetic differentiation for phenotypic plasticity, which might have contributed to adaptation under contrasting environmental heterogeneity during the domestication of rice.
National Agricultural Research Center for Hokkaido Region, Hokkaido, Japan.
Hiroyuki
H
Shimizu
Masamichi
M
Maruoka
Naofumi
N
Ichikawa
Akhil Ranjan
AR
Baruah
Naohiro
N
Uwatoko
Yoshio
Y
Sano
Kazumitsu
K
Onishi
D032461:Chromosomes, Plant; D018556:Crops, Agricultural / Q000235:genetics; D018744:DNA, Plant / Q000378:metabolism; D017343:Genes, Plant; D018745:Genome, Plant; D012275:Oryza / Q000235:genetics*; D010641:Phenotype; D040641:Quantitative Trait Loci
D018744:DNA, Plant