Network size-dependent impact on vegetative growth and sexual reproductionin clonal patches of white clover (Trifolium repens L.)

7 August 2018

Dominiak, Martyna; Lewandowski, Arkadiusz; Gąbka, Maciej; Lembicz, Marlena

In natural habitats, clonal plants form interconnected ramet networks of varied sizes. In large and small networks, ramets may be presumed to apply distinct strategies of investing in vegetative growth and sexual reproduction. This very hypothesis was tested in the course of our experiment in the field. The study encompassed 16 patches of white clover (Trifolium repens L.), which were divided into two groups: small and large. Separate zones, i.e., central, middle and marginal, were isolated within each clonal patch. In small networks, the share of sexually reproducing ramets is prevalent compared with vegetative growth, while the opposite is the case in large ones: vegetative growth is the predominant mode of proliferation. The highest quantity of ramets which reproduced sexually was observed in the outlying regions of large networks. The findings were elucidated (1) with respect to habitat resources used by ramets in networks, and (2) by means of the model of optimal allocation of resources to sexual and vegetative reproduction in perennial plants. It is our conviction that the factor which significantly promoted increased sexual reproduction of ramets in the small patches was more extensive access to water and nutrients, whose availability was in turn limited in the large patches.