Contrasting architectural and reproductive parameters in Mimosa maguirei in response to holoparasitism by Pilostyles blanchetii

Abstract

Parasitic plant species, such as holoparasites, develop exclusively within the tissues of their hosts, are devoid of photosynthetic capability, and cause changes in their hosts. In this study, we analyse the effects of the holoparasitic species Pilostyles blanchetii on Mimosa maguirei. We assessed the effects of the holoparasite on the architecture and development of the host plant through the height, the number of branches and the number of leaves. The influence of the holoparasite on the reproductive performance of the host was tested by evaluating the number of fruits and seeds produced by M. maguirei. The holoparasite Pilostyles blanchetii negatively affected the height of M. maguirei; however, there was a positive effect on the number of branches and leaves of the host, perhaps indicating resource manipulation by the holoparasite. In relation to reproductive performance, there was a reduction in the number of fruits and seeds in parasitized individuals. Overall, this study indicates strong changes in host plant architecture and particularly a reduction in the reproductive performance of parasitized plant individuals.