Introduction

This popular booklet, already in its fourth edition, is designed as a quick guide for identifying maize diseases. Based on previous editions produced by CIMMYT Maize pathologist, Carlos De Leon, the new work has been updated by contributions from CIMMYT maize pathologist Dan Jeffers. It is intended for field use by agricultural technicians and maize producers, and the taxonomic short forms of the various pathogens are deemed to be appropriate and adequate. For fungal pathogens, both the sexual (teleomorph) and asexual (anamorph) names of the fungi are often included. Several modifications in nomenclature have been made since the last edition. Common names of the diseases are designated mostly following the nomenclature described by A.J. Ullstrup (1985. Plant Disease 69:658-659). The text comprises a brief description of common maize diseases, of their causal agents, and of their symptoms. Additional diseases and new information have been included, based on advances in science since the previous edition. There are numerous color photographs of diseased plants. A diagnostic key is included as an appendix. The text is divided according to the four causal agents for maize diseases: fungi, bacteria, viruses, and mollicutes. Fungal diseases are presented in the following sequence: foliar diseases, stalk rots, and ear rots. Most diseases covered are economically significant or have the potential to become so.