7 

 November 1956 ARS-33-33 



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United States Department of Agriculture 

 [M'.J. Agricultural Research Service. 



^BIOCLIMATIC CABINETS USED IN STUDIES ON 

 THE MEXICAN FRUIT FLY AND THE PINK BOLLWORM v 



By N. E. JUitters, Entomology Research Branch, P. S. Messenger, 

 University of California Agricultural Experiment Station, and C. N. 

 Husman, Entomology Research Branch 



Studies making use of especially designed cabinets to determine 

 the effect of climatic conditions on the Mexican fruit fly ( Anastrepha 

 ludens (Loew)) and the pink bollworm ( Pectinophora gossypiella 

 (Saund.)) were undertaken at Brownsville, Tex., at the conclusion 

 of similar studies on several fruit flies in Hawaii. (Chris tenson 

 2, Flitters and Messenger 3^ and Messenger and Flitters b). These 

 studies are concerned with determining the ability of the insects to 

 develop and reproduce under various conditions of temperature, 

 humidity, and light when adequate food, water, and acceptable ovi- 

 positional substrate are in constant supply. It is realized, however, 

 that other physical and biotic factors may influence populations and 

 affect activity and reproductivity of adults, since a species may not 

 inhabit an ecological area that climatically and geographically appears 

 to be most suited to its requirements. 



A number of individuals and agencies have participated in the devel- 

 opment of bioclimatic cabinets. Stone (8) devised an instrument for 

 regulating fluctuating temperatures, and carried on bioclimatic studies 

 of the Mexican fruit fly with such equipment in Mexico City. Munger 

 (1) devised another instrument to accomplish the same purpose. In 

 preparation for the studies in Hawaii, specifications for bioclimatic 

 cabinets were drawn up by Department of Agriculture officials in con- 

 sultation with numerous government and industrial refrigeration 

 engineers. The instruments used to control cabinet performance 

 have been described by Camp (1). The studies conducted in Hawaii 

 established the suitability of this equipment and showed it to be efficient, 

 reliable, and relatively free of operational difficulty. 





