Patterns of reproductive effort inArabidopsis thaliana: Confounding effects of size and developmental stage

Abstract

AbstractWe demonstrate for the annual Arabidopsis thaliana, that reproductive effort (RE) varies with plant size but is affected more directly by developmental stage; i.e. RE is “stage-dependent”. We evaluated plant size and RE under a constant environment with two harvest criteria, and under a variable environment (a range of densities) with one harvest criterion. Plants of 10 genotypes were grown singly and harvested either at maturity of the first fruit (early) or at complete senescence (late). Plants from a subset of 3 genotypes were grown at 6 additional densities and harvested at maturity of the first fruit. For plants grown singly, later harvest resulted in significantly higher RE (seed biomass / total remaining above ground biomass) and larger plant size than early harvest. Conversely, RE decreased with increasing size for plants grown under a range of densities and harvested at maturity of the first fruit. We argue that these apparently contradictory relationships between RE and size are a conseq...