Kaolin, a reflective white mineral, applied to excised cotton squares, squares on cotton plants, or to the foliage initially resulted in lower boll weevil injury to squares. Boll weevils made more use of treated cotton when unused, untreated squares were increasingly in short supply. It appears that boll weevils make host selections based to some extent on color. Field trials showed that boll weevils might distinguish among cotton fields based on color differences caused by kaolin, and the ability to distinguish appears to influence levels of damage. Square damage in the plots treated with kaolin was reduced, except in some cases when rain washed the kaolin off the foliage. Although kaolin application in the small plot test was not always associated with increased yield, significantly higher yields were obtained in the small plots as compared to adjacent cotton fields planted on the same date and with the same variety that were not treated with kaolin. Kaolin application was associated with reduced Cicadellidae populations, and to lesser extents, some other arthropod groups, and increased cotton aphid populations.
Species 1: Coleoptera Curculionidae Anthonomus grandis grandis (boll weevil)
Keywords: kaolin, cotton
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA