Genotype-environment interaction and developmental regulation in arabidopsis thaliana: I. Inbred lines; description

Abstract

1. In principle, the evolutionary role of genotype-environment interaction in the population genetics of a species may take one or other of two mutually exclusive forms; the expression of a metrical character may be buffered against the environment (the character is developmentally stable) or may vary in an adaptive manner with the environment (the character is developmentally flexible). 2. The relationship between three primary characters, flowering time, height and basal leaf number, on the one hand, and the fitness character, siliqua number on the other, has been examined in thirty-three inbred lines of Arabidopsis thaliana raised at 150, 200 and 25° C. in controlled environments, with this point of view in mind. 3. Though the genotype-environment interaction which all four characters display is small relative to the total phenotypic variance, it is large relative to the genetic variance of the character. 4. The relationship between the performance of a line and the environment in which it is raised is a simple one in that this relationship is essentially linear for both the primary and the fitness characters. 5. The relationship between flowering time and siliqua number suggests that the development of the former is generally well-buffered in those lines with a higher than average siliqua number; that is, the development of this character is better stabilised in these lines than in others. 6. Those lines whose height changes least with the environment, on the other hand, produce in general a lower than average number of siliquae; thus the development of this character in lines with a superior reproductive performance, appears to be able to respond in a flexible or adaptive manner to variation of the environment. 7. Not all lines with respect to either flowering time or height accord with these general conclusions, however, and there appears to be no predominant mode with regard to the development of the third primary character, leaf number. © 1970, The Genetical Society of Great Britain. All rights reserved.