The members of the genus Fusarium are among the most important plant pathogens in the world. In recent years the genus has acquired additional importance as many Fusarium species have been shown to produce mycotoxins causing both animal and human diseases. One of the problems encountered by workers interested in Fusarium species, particularly in the toxigenic species, is correct identification of each strain. This problem was the impetus for the preparation of this volume.The taxonomy of the genus Fusarium has been the subject of controversy for many years. Die Fusarien, published in 1935 by Wollenweber and Reinking, has been used as a starting point in this book. Since 1935 several other taxonomic systems have been proposed for this genus. These systems vary from one with over 90 species to one with only nine species; several other systems fall between these two extremes.