Density-dependent effect of allelopathy on germination and seedling emergence in two Ipomoea species

Background Density in inter and intraspecific plant-plant interactions affects the action modes of allelopathy (autotoxicity, negative and positive allelopathy). Some seeds exude compounds that inhibit the germination of others. Ipomoea murucoides and I. pauciflora are sympatric tree species that form patches at the local scale where one or the other dominates, possibly due to allelopathy in the seeds. The objective of this study was to determine the possible density-dependence of the allelopathic effect among seeds of these species through the measure of seed germination and seedling emergence.