Effects of sexual reproduction on growth and vegetative propagation in the perennial geophyte Arum italicum (Araceae)

The influences of sexual reproduction on growth and vegetative propagation were analysed in three populations of the geophyte Arum italicum Miller (Araceae). In an observational study using multiple regression, a negative influence of reproduction on tuber mass was detected for two populations. In an experimental study, "control" and "inflorescence removal" treatments were imposed on plants from one of the populations. Tuber growth was significantly lower in "control" plants than in "removal" plants, indicating the existence of a somatic cost of reproduction. The somatic cost of reproduction was decreased by an increasing degree of temporal coincidence between leaves and reproductive structures on the plant. Neither the observational nor the experimental studies showed any negative effect of sexual reproduction on vegetative propagation.