RESPONSES OF THE MEXICAN FRUIT FLY (DIPTERA: TEPHRITIDAE) TO TWO HYDROLYZED PROTEINS AND INCORPORATION OF PHLOXINE B TO KILL ADULTS

Authors: Moreno, Daniel; Mangan, Robert

Submitted to: Proceedings of American Chemical Society National Meeting
Publication Type: Book / Chapter
Publication Acceptance Date: 12/14/1995
Publication Date: N/A
Citation: N/A

Interpretive Summary: The cost of control/eradication programs for fruit flies in the Americas runs several million dollars annually. In eradication programs, insecticide-baits are one of the essential control strategies. However, the general public demands the use of insecticides be reduced to an absolute minimum. Malathion- protein hydrolyzate (NuLure) sprays are the standard treatment for fruit fly control programs throughout the world. Malathion is a contact, stomach poison, and NuLure is the bait. We found Mazoferm, a protein hydrolyzate, more attractive and phagosti- mulating than NuLure. The addition of the food/cosmetic colorant phloxine B to a Mazoferm formulation caused light-activated death in flies; they died in less than 1 hour at concentrations of 2 and 4%. Fly kill was increased by adding the adjuvant SM-9 and additionally with soybean oil. The attraction of the new dye- bait to flies remained the same despite all additives. These findings showed that (1) NuLure can be easily replaced with more attractive and palatable Mazoferm and (2) the insecticide malathion can be replaced with a photoactive dye. Therefore, we propose the use of an effective, more attractive, and safer alternative to the malathion-bait. The new formulation can be safely used among human habitats, is safe to natural enemies in agricultural systems because it does not kill on contact, and is environmentally safe because it degrades relatively fast with sunlight.

Technical Abstract: In fruit fly eradication programs, insecticide-baits are one of the essential control strategies. The bait normally used is NuLure in combination with the insecticide malathion. However, social pressures demand that the use of insecticides be reduced to an absolute minimum. We found in the field that the hydrolyzed protein Mazoferm is more attractive to Mexican fruit flies than NuLure. Mazoferm also stimulates feeding more so than NuLure in the Mexican fruit fly. In independent tests Mazoferm with fructose stimulated fly feeding beyond that of fructose alone; whereas NuLure consumption was increased by adding fructose but flies consumed less than fructose alone. In choice tests a Mazoferm-fructose formulation was consumed more by flies than a NuLure-fructose formulation. The photoactive dye phloxine B mixed with Mazoferm-fructose (dye-bait) was acceptable to flies as measured by their consumption. When these flies were exposed to sunlight, they died in less than 1 h at concentrations of 2 and 4%. The effective kill of the dye-bait was increased by adding the adjuvants SM-9 or Kinetic and further increased by adding soybean oil. The attraction of the dye-bait to flies with all its additives did not diminish below that of Mazoferm- fructose alone and this attraction was significantly increased by adding acetic acid.