Resource allocation to growth, reproduction and survival in Gladiolus : The cost of male function

Abstract

Theoretical models of life‐history evolution assume trade‐offs between present and future reproduction and/or survival. Models of the evolution of sex assume trade‐offs between male function and female function. Generally, experiments designed to evaluate the cost of reproduction on other functions tend to ignore male function. The present work on Gladiolus takes into account simultaneously the different primary functions of the plant and separates sexual reproduction into one male component (pollen production) and one female component (seed production). The study of environmental (within‐clone), between‐clone and genetic correlations using strains of Gladiolus and principal component analysis show that trade‐offs exist between male function, female function and survival, including both characters of plant vigour, perennation (corm production) and vegetative propagation (cormel production). Phenotypic correlations, using different species and species‐hybrids, have been obtained which confirm these results. In particular, these results underline the importance of the impact of pollen production on the other functions. Copyright © 1991, Wiley Blackwell. All rights reserved