Laboratory outlines in plant pathology

II Professor of Plant Pathology

Assistant Professor of Plant Pathology Assistant Professor of Plant Pathology

W. HOWARD RANKIN

Assistant Professor of Plant Pathology

NEW YORK STATE COLLEGE OF AGRICULTURE AT

CORNELL UNIVERSITY

ITHACA, N. Y.

PUBLISHED BY THE AUTHORS

SE.73I

■ws-

COPYRIGHT, 191 6 H. H. WHETZELL rj4 I »

W. F. Humphrey, Printer, Geneva, N. Y.

Preface

THESE outlines are designed solely for the purpose of most effectively acquainting the student with the laboratory materials presented in this course. They are the result of several years of experience and test in actual practice work. They have been frequently revised. It is expected that they will now be revised and reprinted at least every two years.

Although the acquisition of a body of facts is an important and necessary part of the work in such a course a more vital feature is the training in logical methods of acquiring them. The student is urged to follow his outline carefully, making sure at each step, that the outline and the materials before him agree. The same sequence of treatment is followed throughout all the outlines. This sequence in procedure should be mastered promptly. The term papers will afford opportunities for determining how well the student has grasped the logic of this procedure.

The grouping of diseases here presented is, we believe, an important step in diverting attention from the domination of systematic mycology in phytopathological teaching and writing, and of directing it toward the more logical classification and study of diseases on the basis of the pathological phenomena exhibited. At the same time the subgrouping of the diseases, according to the chief etiologic factor involved, provides for a point of view still generally presented in the teaching of plant pathology- .

It is not expected that all the diseases herein outlined will be covered in a three hours' course. The instructor will make such selections from the different groups as will best serve his purpose in illustrating the fundamentals of the subject in the case of the students in his classes. No laboratory practice in the methods of control of the diseases studied is provided. That phase of the subject is fully treated in the course based upon and following this, namely, The Principles of Plant Disease Control.

These outlines are designed specifically for the work as given at Cornell University and without any attempt to adapt them for use in other institutions. It is hoped, ho>vever, that teachers elsewhere may at least find them helpful and possibly usable in their classes.

Acknowledgments are due Mr. Chas. Chupp, instructor in the department of Plant Pathology for the preparation of a number of the outlines. We also gratefully acknowledge the friendly advice and assistance of the Comstock Publishing Company in our effort to make the cost of these outlines to the student as reasonable as possible.

THE AUTHORS.