Genetics of Brassica campestris. 1. Genetic constraints on evolution of life-history characters

  • Dorn L
  • Mitchell-Olds T
  • 28

    Readers

    Mendeley users who have this article in their library.
  • 66

    Citations

    Citations of this article.

Abstract

Energy allocation arguments suggest a possible tradeoff between timing and magnitude of reproduction: plants that postpone reproduction may accumulate greater resources and consequently produce more offspring. However, early reproduction may be favored when adult mortality is high. Tradeoffs among life- history characters may be a consequence of constraints imposed by genetic and environmental covariation among traits. In this paper we examine the genetic basis of the relationship between timing and magnitude of reproduction in an annual plant, Brassica campestris, by selecting to change flowering date and plant size in each of four directions (early and large, late and large, early and small, or late and small). There is a strong positive relationship between flowering date and flowering height. The response to selection was greatest along the axis of positive genetic covariation. Populations may evolve to become early flowering and small or late flowering and tall, but there is little response for the alternative combinations of characters. In this instance, the constraints imposed by quantitative genetics are in striking accord with predictions that might be made on physiological, energetic, or ecological grounds.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Lisa A Dorn

  • Thomas Mitchell-Olds

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free