peak at approximately 500 m/i. The rice weevil showed no significant preference for the 

 various wave bands and one species, the flat grain beetle, did not react in sufficient 

 numbers to permit analysis. All species responded poorly to wave bands at 600 m/i. There 

 was practically no response at Z80.4 m/i. Figure 1 shows the relative response curves 

 obtained for the rice weevil, the Indian-meal moth and the Angoumois grain moth. Fur- 

 ther tests were conducted in which the energy levels were increased up to 1 1 times the 

 arbitrary level used in the previous studies. It was found that the response reaction 

 of all species of insects was increased significantly by an increase in intensity. For the 

 almond moth, the region of peak response shifted from 546.1 m/i in the green to 365.4 

 m/i in the near ultraviolet. 



Laboratory Studies of the Spectral Response of Pink Bollworm Moths 



Laboratory investigations of the spectral response characteristics of pink bollworm 

 moths were conducted during 1957, 1958, and 1959 by the Farm Electrification Research 

 Laboratory, A.R.S., U.S.D.A. , at College Station, Tex. Emphasis was given to work 

 with this particular cotton insect pest as a result of work in 195Z which established 

 that the pink bollworm moth was highly attracted to electric lamps with principal emis- 

 sions in the near ultraviolet region of the spectrum (7). These investigations have been 

 carried on in conjunction with work on the design and operation of improved survey 

 type electric insect traps for aid in control efforts against this pest. 



Three different test series have been completed at this time. For convenience 

 of identification, these will be referred to as "Test Series I", "Test Series II", and 

 "Intensity Studies" in the discussions which follow. 



Test Series I: The objective of Test Series I was to determine the response of the 

 pink bollworm moth to different narrow wavelength bands of equal energy radiation within 

 the ultraviolet and visible regions of the spectrum. The test equipment included a 10" x 

 10" x 98" sheet metal tunnel (flat black interior) with provisions for compartmenting 

 into five sections by means of sliding gates; a Bausch and Lomb grating monochromator 

 adapted to utilize General Electric Co. Type H85-C3, H100-A4, and 18A/T10/4 lamps; 

 General Electric Co. Type H100-BL4 lamp with filters for isolation of the 365.4 mercury 

 line; a special photometer consisting essentially of a Varian Model G- 10 recorder, a 

 Type 1P28 multiplier type phototube, a high voltage D.C. power supply and appropriate 

 circuitry. (See Stermer 10 , for a complete description of the construction and calibra- 

 tion of this photometer.) 



In this series of tests the response of pink bollworm moths to 18 different wavelength 

 bands was determined by comparing the effectiveness of 365.4 m/i with the following 

 wavelength bands: 



Milli- Milli- Milli- 



micron micron micron 



280 385 515 



303 405 546 



313 420 560 



340 434 578 



350 460 600 



365 486 625 



The H100-BL 4 lamp was used with Corning glass filters Nos. 7380 and 5860 to pro- 

 vide the constant source of 365.4 m/i used as a standard of comparison. The 250 mm. 



10 See footnote 9. 



14 



