Diversity and host preference of leaf endophytic fungi in the Iwokrama Forest Reserve, Guyana

Abstract

Endophytic fungi were isolated from living symptomless leaves of 12 tree species from two locations in the Iwokrama Forest Reserve, Guyana. Sixty-four fungal morphotaxa were characterized from 2492 cultures, which were derived from a total of 2520 sample units. Species of Colletotrichum, Nodulisporium, Pestalotiopsis and Phomopsis were most frequently isolated. Colonization was greater in samples from the midrib than in those from laminar tissue, and slightly greater at the tip of the lamina compared with the base of the leaf. In contrast to studies in temperate ecosystems, no distinct fungal communities were identified for individual plant species, suggesting that the degree of host preference is low. The implications for estimation of fungal diversity in tropical systems are explored.

• fungal diversity
• host preference
• leaf endophytes
• neotropical mycology

The research described here was sponsored through a grant from the European Union to the Iwokrama Center for Rainforest Conservation and Development, as a component of a combined bioinventory and bioprospecting program. David Hammond and the Iwokrama staff are thanked for advice, facilitation and assistance in sample collection. At CABI Bioscience, technical aspects of the research were ably supported by Ann Ansell, Thelma Caine, Teresa Clayton and Astrid Webster. It is a pleasure to acknowledge the helpful comments made by Betsy Arnold (University of Arizona), who also kindly made available an unpublished manuscript. Access to the free ecological statistics software package EstimateS 6, written by Robert Colwell (University of Connecticut) is also gratefully acknowledged.