High diversity and low specificity of fungi associated with seedless epiphytic plants

Epiphytes, which grow on other plants for support, make up a large portion of Earth's plant diversity. Like other plants, their surfaces and interiors are colonized by diverse assemblages of fungi that can benefit their hosts by increasing tolerance for abiotic stressors and resistance to disease or harm them as pathogens. Fungal communities associated with epiphytic plants and the processes that structure these communities are poorly known. To address this, we sampled seven epiphytic seedless plant taxa in a Costa Rican rainforest and examined the effects of host identity and microhabitat on external and endophytic fungal communities. We found low host specificity for both external and endophytic fungi and weak differentiation between epiphytic and neighboring epilithic plant hosts. High turnover in fungi within and between hosts and habitats reveals that epiphytic plant-associated fungal communities are highly diverse and suggests that they are structured by stochastic processes.Abstract in Spanish is available with online material

Automated summary

Epiphytes, which grow on other plants for support, harbor diverse fungal communities on their surfaces and interiors that can benefit or harm their hosts. However, our understanding of these fungal communities and their structure is limited. By studying seven epiphytic plant taxa in a Costa Rican rainforest, we found that the fungi associated with these plants were not highly specific to host species and showed weak differentiation between epiphytic and neighboring plant hosts on rocks. The high turnover of fungi within and between hosts and habitats suggests that epiphytic plant-associated fungal communities are highly diverse and likely structured by stochastic processes.