Contrasting effects of plant-soil feedbacks on growth and morphology of physically-connected daughter and mother ramets in two clonal plants

Aim Soil abiotic and biotic conditions are often spatially variable, challenging plants with a heterogeneous environment consisting of favorable and unfavorable patches of soil. Many stoloniferous clonal plants can escape from unfavorable patches by elongating stolon internodes, but aggregate in favorable ones through shortening stolon internodes. However, whether the connected mother and daughter ramets of these plants can use their stolons to respond to plant-soil feedbacks (PSFs) is largely unknown. Methods In the conditioning phase, we grew either Hydrocotyle vulgaris or Glechoma longituba clonal plants separately in mesocosms to condition bulk soil. In the feedback phase, we grew connected mother and daughter ramets of each species in soil inoculated with the unsterilized or sterilized soil conditioned by conspecifics. We grew the plants for 12 weeks and measured the growth of the mother and daughter ramets separately. Results The daughter ramets of H. vulgaris produced more biomass, greater number of ramets and longer stolon internodes when grown in soil with sterilized inocula than with unsterilized inocula. However, no difference was found for the daughter ramets of G. longituba. In general, for both species, soil inoculum treatment on the mother ramet did not influence the performance of daughter or mother ramets. Conclusions We conclude that biotic PSFs differed not only among different species, but also in physically-connected ramets of the same clone. Moreover, physiological integration or plasticity in stolon internode lengths cannot help H. vulgaris alleviate the negative effects of PSFs.

Automated summary

This study investigated the response of two stoloniferous clonal plants to plant-soil feedbacks, and found that biotic plant-soil feedbacks differed among different species and physically-connected ramets of the same clone. Moreover, physiological integration or plasticity in stolon internode lengths could not help Hydrocotyle vulgaris alleviate the negative effects of plant-soil feedbacks.