Path analysis of natural selection via survival and fecundity across contrasting environments in Avena barbata. Journal Article uri icon

Overview

abstract

  • We employed path analysis to analyse natural selection through two major fitness components in each of three contrasting environments. Using a randomized block design, 188 Recombinant Inbred Lines (RILs) derived from a cross between contrasting ecotypes of Avena barbata were planted in common gardens in the greenhouse, and in two field sites typical of each ecotype's native habitat. Individuals were monitored for germination phenology, early growth, survival, final size, flowering phenology, reproductive allocation, fecundity and lifetime reproductive success. The variance/covariance matrix of the RIL (genotype) means was fit to a path model in which total fitness was made up of survival and fecundity (of survivors) components. In the greenhouse, all fitness variation was determined by fecundity variation (with no mortality), which was itself primarily determined by reproductive allocation mediated by date of first flowering. By contrast, in the field, early growth was the major determinant of survival, and final size was the major determinant of fecundity. Both components of fitness affected lifetime reproductive success equally in the field. Thus the major difference between greenhouse and field seems to be a shift from selection on allocation patterns in adults, to selection on resource acquisition, especially at earlier life stages. The pattern of selection was similar in the two field sites, despite the contrasting environments.

publication date

  • December 1, 2009

has restriction

  • bronze

Date in CU Experts

  • October 28, 2013 11:11 AM

Full Author List

  • Latta RG; McCain C

author count

  • 2

Other Profiles

Electronic International Standard Serial Number (EISSN)

  • 1420-9101

Additional Document Info

start page

  • 2458

end page

  • 2469

volume

  • 22

issue

  • 12