SURVEYING MOSSES FOR FUNGICIDAL ACTIVITY

Abstract

The emergence of resistance to current fungicides is of serious concern because of the widespread diseases caused by fungi. One approach to this problem is to discover new compounds that have antifungal properties. Plants are extensively attacked by fungi and have evolved many defenses. These include fungicides and other defenses, such as a waxy cuticle, that make attack difficult. The mosses (Bryophyta) lack a cuticle. This makes them a likely group to survey for fungicidal activity because they may have additional chemical defenses. In this study, both aqueous and ethanolic extracts were made from crushed mosses and tested for their effect on growth of the yeast�Saccharomyces cerevisiae. �Mosses were collected across a broad geographical range (Georgia, Arkansas, and Alaska) to test the hypothesis that resistance to fungal attack may be higher in mosses adapted to warm and moist environments. Results include the demonstration of fungicidal activity in some, but not most, of the mosses. There was no correlation with geographical origin.� Both solvents seem able to extract compounds that will suppress yeast growth. In addition, we show that fungicidal properties may be lost during drying.� Several mosses showed strong enough antifungal activity that further investigation seems warranted.