Infection strategies of plant parasitic fungi

Abstract

How plant pathogens attack their host plants is one of the most interesting questions in plant pathology. Numerous fungi and fungus-like organisms cause some 10,000 different diseases in plants (Pennisi, 2001). Fungal diseases of plants cause economic losses by reducing seed germination, destroying plants or the harvesting products and by secreting secondary metabolites that are toxic for man and animals. Successful colonization of the habitat plant, including uptake of nutrients and reproduction, greatly depends on an efficient mode of infection. Plant parasitic fungi have developed various strategies to enter their hosts, and to establish direct contact with them. Successful interactions result in devastating plant diseases. In many cases this means the production of very large amounts of spores that are wind dispersed from one susceptible host to another. Furthermore, there are several examples described of long-distance dispersal of fungal spores by wind that can spread plant diseases across and even between continents and allow invasion into new territories (Brown and Hovmøller, 2002).