LIBRARY 

 RECEIVED 



Circular No. 600 



May 1941 • Washington, D. C. 



MAY 2 3 1941 



U.S. Depar 



:ricuture 



UNITED STATES DEPARTMENT OF AGRICULTURE 



Mortality of the Apple Maggot in 

 Held in Cold Storage 



Fruit 



By P. J. Chapman, agent, Division of Fruit Insect Investigations, Bureau of Ento- 

 mology and Plant Quarantine, and chief in research, New York State Agricultural 

 Experiment Station, and A. D. Hess, assistant in research, New York State 

 Agricultural Experiment Station. 



United States Department of Agriculture, Bureau of Entomology and 

 Plant Quarantine, in cooperation with the New York State Agri- 

 cultural Experiment Station 



CONT 



Page 



ENTS 



Page 

 5 





Tests at 32° Fahrenheit 



Tests at 36° Fahrenheit 



Tests at 40° Fahrenheit... _ 



Summary _. 



6 



Equalization of fruit and air temperatures 3 



7 



7 



9 



INTRODUCTION 



In recent years the sanitary requirements of a number of foreign 

 countries have made it necessary to limit exportation of apples from 

 the United States to fruit found free of infestation by the apple maggot 

 (Rhagoletis pomonella (Walsh)). This species is indigenous to the 

 Northeastern States and southeastern Canada, where it normally 

 occurs in many unsprayed or inadequately sprayed orchards. 



The apple maggot may be controlled satisfactorily, according to 

 domestic standards, through the use of certain stomach-poison insecti- 

 cides applied to the apple trees in sprays or dusts. 1 Such treatment 

 may fall short, however, of providing the 100-percent efficiency re- 

 quired to meet the export standard. A situation has thus been created 

 whereby an otherwise acceptable product is excluded from certain 

 foreign markets on account of the presence of an occasional live apple 

 maggot egg or larva. As it would be impracticable, if not impossible, 

 to sort out all the infested fruits, owing to the extreme inconspicuous- 

 ness of external signs of infestation, there has seemed to be a need for 

 the development of a means of destroying the eggs and larvae in situ. 



1 Chapman, P. J., and Hammer, O. H. a study of apple maggot control measures. N. Y. State Agr. 

 Expt. Sta. Bui. 644, 40 pp., illus. 1934. 



