Fig 1.
Schematic showing dependence of phenotypic plasticity parameters on the order of the environments.
Genotype A1 and A2 are represented in blue and red colours respectively. VarE refers to environmental variance whereas refers to sum of slopes, as described in Methods. y-axis denotes the phenotype and x-axis denotes discrete environments arranged in different orders. (A) Genotype A1 and A2 have significant differences in multiple environments but are both equally plastic. (B) A1 is plastic and A2 is canalised. (C) and (D) shows the same environments arranged in different orders which have no effect on environmental variance but have different impact on reaction norms or sum of slopes.
Fig 2.
Categorisation of environments based on phenotypic variance.
(A) Phenotypic variance of ~1,000 segregants (x-axis) across different environments (y-axis). (B) Phenotypic variance of ~1,000 segregants (y-axis) within each environment (x-axis). Green colour refers to environments with low phenotypic variance (Lv) and pink refers to environments with high phenotypic variance (Hv). The dashed line indicates the median of the distribution. (C) Comparison of phenotypic variance of ~1000 segregants between Hv (y-axis) and Lv (x-axis) environments. A low regression coefficient indicates poor correlation between the two.
Table 1.
Comparison of QTL and plasticity QTL.
Fig 3.
QTL mapping of environmental variance in Hv and Lv environments.
(A) LOD score distribution plot of environmental variance across Hv environments. The dashed line represent the LOD cut off of 2.0, permutation P < 0.01. (B) Dot plot of marker at chrV (201,987). (C) Dot plot of marker at chrXIII (46,211). (D) LOD score distribution plot of environmental variance across Lv environments. The dashed line represent the LOD cut off of 2.0, permutation P < 0.01. (E) Dot plot of marker at chrXIV (374,661). Red and blue colours denote BY and RM alleles respectively.
Fig 4.
QTL mapping of reaction norms in Hv and Lv environments using allele specific orders.
(A) and (B) show LOD score distribution plots of reaction norms using allele specific order across Hv environments. The dashed line represent the LOD cut off of 4.0 in A and B respectively, permutation P < 0.01. (C) and (D) show LOD score distribution plots of reaction norms using allele specific order across Lv environments. The dashed line represent the LOD cut off of 5.0 in C and D respectively, permutation P < 0.01. Red and blue plots indicated QTL mapping performed by canalising BY and RM alleles, respectively.
Fig 5.
Phenotypic plasticity observed within canalised mean effects.
Reaction norms of segregants carrying RM allele of marker chrXIII (45,801) in Hv environments (A), and BY allele of marker chrXIV (364,968) in Lv environments (B). In both the plots, the environments are arranged such that the mean phenotype, denoted by the black line, has the least possible value of sum of slopes. Reaction norms for 10 random segregants have been highlighted as blue, RM, and red, BY in the two plots and reaction norms of other segregants are represented in grey lines.
Fig 6.
Comparison of mean and variance of allelic reaction norms.
Comparison of difference in mean and variance of the alleles of peaks identified in 10 different random orders in Hv (A) and Lv (B) environments. x-axis shows the difference between mean value of sum of slopes of alleles for different peaks, BY-RM, and y-axis refers to difference between variance of sum of slopes of alleles, BY-RM. See S3 Table for more details.