Data from: Clonal integration enhances performance of an invasive grass

While many clonal plants are highly successful invaders, not all clonal
plants share resources, often making the contribution of clonal
integration (i.e., the translocation of resources among ramets) to
invasion unclear. To determine if photosynthate translocation augments
performance of emerging daughter ramets for a globally invasive grass
(Imperata cylindrica), we combined a 13CO2 pulse-chase experiment with a
greenhouse experiment manipulating light levels and rhizome attachment.
Model simulations were also used to determine if clonal integration
facilitated photosynthate translocation, if the performance of daughter
ramets was enhanced by clonal integration, and if shaded ramets benefited
relatively more from transferred photosynthate. We found that acropetal
photosynthate transfer occurred between all sampled parent-daughter ramet
pairs and that this resource sharing led to higher biomass and tiller
production when rhizomes between parent and daughter ramets were intact.
We also found that the benefits of integration to recipient clones
outweighed the costs to donors, since there was no reduction in parent
plant performance due to sharing. Additionally, analysis of our data show
that photosynthate transfer was likely of greater benefit in overcoming
growth constraints in the shade than in the full sun (posterior
probability ~ 96.5%), a result that is further supported by our numerical
simulations from a basic growth model. Thus, photosynthate transfer is a
probable mechanism that explains why clonal integration can be
particularly beneficial in heterogeneous resource environments. More
generally, resource sharing among clonal plants may be a critical but
underappreciated trait of invasive species.