Tingting Guo, Jialu Wei, Xianran Li, Jianming Yu

J Exp Bot.; 2024 Feb 2; 75(3):1004-1015. doi: 10.1093/jxb/erad398.

Abstract

Phenotypic plasticity is an important topic in biology and evolution. However, how to generate broadly applicable insights from individual studies remains a challenge. Here, with flowering time observed from a large geographical region for sorghum and rice genetic populations, we examine the consistency of parameter estimation for reaction norms of genotypes across different subsets of environments and searched for potential strategies to inform the study design. Both sample size and environmental mean range of the subset affected the consistency. The subset with either a large range of environmental mean or a large sample size resulted in genetic parameters consistent with the overall pattern. Furthermore, high accuracy through genomic prediction was obtained for reaction norm parameters of untested genotypes using models built from tested genotypes under the subsets of environments with either a large range or a large sample size. With 1428 and 1674 simulated settings, our analyses suggested that the distribution of environmental index values of a site should be considered in designing experiments. Overall, we showed that environmental context was critical, and considerations should be given to better cover the intended range of the environmental variable. Our findings have implications for the genetic architecture of complex traits, plant-environment interaction, and climate adaptation.

See https://pubmed.ncbi.nlm.nih.gov/37819624/

Figure 1: A schematic diagram of different scenarios of reaction norms. (A) Reaction norms of two genotypes (G1 and G2) across the entire range of environments. (B) Reaction norms obtained from a small range of environments. (C) Reaction norms obtained from a medium range of environments. (D) Reaction norms obtained from a large range of environments. In (B–D), bold lines indicate the obtained reaction norm within the studied range; dashed lines indicate the extrapolated sections, which can deviate in (B) and (C) from (A); light gray lines indicate the reaction norm across the entire range. In (A–D), bold ticks indicate environments used to obtain the reaction norms, and gray ticks indicate environments not used.