UNITED STATES DEPARTMENT OF AGRICULTURE 



BULLETIN No. 686 



Contribution from the Bureau of Plant Industry 

 WM. A. TAYLOR, Chief 



Si^S^^^WfM. 



Washington, D. C. 



PROFESSIONAL PAPER 



June 24, 1918 



FURTHER STUDIES OF THE ROTS OF STRAWBERRY 



FRUITS. 



By Neil E. Stevens, Pathologist, and R. B. Wilcox, Scientific Assistant, Fruit- 

 Disease Investigations. 



CONTENTS. 



Introduction 1 



Rhizopus 2 



Type of rot induced 2 



Importance of careful handling 2 



Importance of low temperature 3 



Washing strawberries 4 



Temperature at time of picking in rela- 

 tion to decay 7 



Page. 



Botrytis 8 



Relation of Botrytis infection to mois- 

 ture conditions 8 



Growth of Botrytis on strawberries un- 

 der refrigeration 9 



Relation of Botrytis to infection by Rhizopus. 10 



Summary 12 



Literature cited 14 



INTRODUCTION. 



The results of the investigations of the rots of strawberry fruits 

 (Fragaria sp.) made by the writers during the two years ended in the 

 spring of 1917 have already been published (10 to 12).^ Since the 

 preparation of these papers the problem has been studied somewhat 

 more extensively. The work for the season of 1917 included field 

 investigations in Florida, Alabama, and Louisiana, with experimental 

 shipments between Hammond, La., and Chicago during April, and 

 field work in Missouri and in the region about Norfolk, Va., in May. 

 Observations were also made of the fruit in the various markets., 

 most of the important markets east of Minneapolis being visited at 

 least once during the season. 



Through the courtesy of H. J. Ramsey and V. W. Ridley, of the 

 C^fiice of Handling and Storage Investigations of Fruits and Vege- 

 tables, one of the writers was able to accompany car-lot shipments of 

 strawberries from Monett, Mo., to St. Paul, Minn., in order to study 

 the condition of these shipments and to include inoculated fruit in 

 the cars. 



The serial numbers in parentheses refer to " Literature cited," at the end of this bulletin. 

 52315°— 18— Bull. 686 



