Some problems in the use of artificial light in crop protection

Abstract

Abstract does not appear. First page follows. Introduction When the author first began to investigate the light reactions of blowfly larvae on the sandy beaches of Lake Erie, during the summers of 1903-1906, little did he suspect that he would be investigating the light reactions of the codling moth, Carpocapsa pomonella (Linn.), in apple orchards in California twenty-five years later. As the laboratory and field notes of the early work in Ohio are examined, two significant points that have been stressed throughout the years may be noted: (1) importance of knowing field habits, as then stated, “… behavior … under natural conditions … should be considered first”; this point was again stressed in 1909 (Herms, 1909); and (2) the importance of wave length and intensity. These early studies convinced the author of the powerful influence of light on the behavior of insects (and of other arthropods) (Herms, 1907a), (b), and suggested the possibility of devising ways and means for the use of artificial light in the control of insects for man’s benefit in crop protection (Herms and Ellsworth, 1934). In spite of many interruptions and some opposition by old-line entomologists, as well as by other interests, some progress of economic importance has been made. As an aid to future work, examination of some of the problems encountered during the course of these investigations seems appropriate. Much of the earlier work was concerned with laboratory studies (largely unpublished) of the color reactions of various species of insects of economic importance, such as the codling moth. These investigations indicated that insects have color preferences, and that such preferences differ markedly for the various species under consideration. Furthermore, the investigations seem to justify the belief that through the use of appropriate monochromats of sufficient light intensity, certain species of harmful insects could be lured to destruction with the exclusion of harmless and beneficial forms. Experimental evidence points to the fact that certain species of insects—particularly crepuscular forms—become active on exposure to low intensities of light and, by an increase in light intensity, might be deterred from performing their egg-laying function; hence the field tests made on the codling moth.