Authors: Kurt Mendgen Stefan G R Wirsel Andreas Jux Jochen Hoffmann Wilhelm Boland
Publish Date: 2006/06/15
Volume: 224, Issue: 6, Pages: 1353-1361
Abstract
Rust fungi are obligate biotrophic pathogens that differentiate a series of specialized cells to establish infection One of these cells the haustorium which serves to absorb nutrients from living host cells normally develops only in planta Here we show that the rust fungus Uromyces fabae Pers Schroet stimulates volatile emission of its host broad bean Vicia faba L Volatiles were identified and shown to be perceived by the fungus in in vitro assays that excluded the host Three of them nonanal decanal and hexenyl acetate promoted the development of haustoria on artificial membranes In contrast the terpenoid farnesyl acetate suppressed this differentiation In assays using whole plants farnesyl acetate reduced rust disease not only on broad bean but also on several cereals and legumes including soybean This natural substance was effective against all rusts tested when directly applied to the host This demonstrated that farnesyl acetate may serve as a powerful novel tool to combat rust fungi including Phakopsora pachyrhizi that currently threatens the production of soybeans worldwide
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