Effects of clonal integration on plant plasticity in Fragaria chiloensis

The ability of clonal plants to transport substances between ramets located in different microsites also allows them to modify the plastic responses o f individual ramets to local environmental conditions. By equalising concen trations of substances between ramets, physiological integration might decr ease responses to local conditions. However, integration has also been obse rved to increase plasticity and induce novel plastic responses in ramets. T o ask how integration modifies plant plasticity in the clonal herb, Fragari a chiloensis, ramets were given either low light and high nitrogen or high light and low nitrogen, simulating a pattern of resource patchiness in thei r native habitat. Ramets in contrasting light/nitrogen treatments were eith er connected or single. Effects of light/nitrogen and connection were measu red at three levels of morphological organisation, the organ, the ramet, an d the clonal fragment. Connection between ramets reduced or had no effect o n plastic responses in leaf size at the level of the plant organ. This sugg ested that integration dampened certain plastic responses. Connection induc ed a new plastic response at the level of the clonal fragment, an increase in allocation to vegetative reproduction in patches of low light and high n itrogen. It is concluded that clonal integration can have different effects on plant plasticity at different levels of plant organisation. It appears that, at least in this species, integration can increase plasticity at the level of the clonal fragment and concentrate vegetative reproduction in par ticular microsite types.