Excerpt from A Dry Rot of Sweet Potatoes Caused by Diaporthe Batatatis Halsted did not regard the disease as serious at that time, which probably explains why he did little or no more work with it. During the 22 years which have elapsed since this disease was first dis covered and described, no additional work has been done with it. It is believed by the writers, after a thorough study of this disease, that. The economic importance of the drv - rot has been obscured by two very serious and prevalent diseases - the stem-rot and the black-rot. It has been further obscured by the fact that there are no external evidences of the organism in the field, it being detected only on the dead vines in the field or on the roots in the storage house a month or more after the cr0p is harvested. In view of these facts, injury which has been occasioned by the dry-rot organism is frequently attributed to other diseases, such as stem-rot or even to drying up due to natural causes. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

The burgeoning demand on the world food supply, coupled with concern over the use of chemical fertilizers, has led to an accelerated interest in the practice of precision agriculture. This practice involves the careful control and monitoring of plant nutrition to maximize the rate of growth and yield of crops, as well as their nutritional value.

For the first time in over 20 years, a comprehensive collection of photographs and descriptions of species in the fungal genus Fusarium is available. This laboratory manual provides an overview of the biology of Fusarium and the techniques involved in the isolation, identification and characterization of individual species and the populations in which they occur. It is the first time that genetic, morphological and molecular approaches have been incorporated into a volume devoted to Fusarium identification. The authors include descriptions of species, both new and old, and provide protocols for genetic, morphological and molecular identification techniques. The Fusarium Laboratory Manual also includes some of the evolutionary biology and population genetics thinking that has begun to inform the understanding of agriculturally important fungal pathogens. In addition to practical “how-to” protocols it also provides guidance in formulating questions and obtaining answers about this very important group of fungi. The need for as many different techniques as possible to be used in the identification and characterization process has never been greater. These approaches have applications to fungi other than those in the genus Fusarium. This volume presents an introduction to the genus Fusarium, the toxins these fungi produce and the diseases they can cause. "The Fusarium Laboratory Manual is a milestone in the study of the genus Fusarium and will help bridge the gap between morphological and phylogenetic taxonomy. It will be used by everybody dealing with Fusarium in the Third Millenium." --W.F.O. Marasas, Medical Research Council, South Africa

It was a compliment to me to be asked to prepare the fourth edition of Westcott's Plant Disease Handbook, and the decision to accept the responsi bility for the fourth edition and now the fifth edition was not taken lightly. The task has been a formidable one. I have always had a great respect professionally for Dr. Cynthia Westcott. That respect has grown considerably with the completion of the two editions. I now fully realize the tremendous amount of effort expended by Dr. Westcott in developing the Handbook. A book such as this is never finished, since one is never sure that everything has been included that should be. I would quote and endorse the words of Dr. Westcott in her preface to the first edition: "It is easy enough to start a book on plant disease. It is impossible to finish it. " This revision of the Handbook retains the same general format contained in the previous editions. The chemicals and pesticides regulations have been updated; a few taxonomic changes have been made in the bacteria, fungi, and mistletoes; the changing picture in diseases caused by viruses and/or viruslike agents has been described. A few new host plants have been added, and many recently reported diseases as well as previously known diseases listed now on new hosts have been included. In addition, photographs have been replaced where possible, and the color photograph section has been retained.