Feromonas De Insectos

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Insect pheromones
FRED E. REGNIER and JOHN H. LAW Department of Biochemistry, University of Chicago, Chicago, Illinois 60637

ABSTRACT The evidence for intraspecies chemical communication in insects is reviewed, with emphasis on those studies where known organic compounds have been implicated. These signal-carrying chemicals are known as pheromones. There are two distinct typesof pheromones, releasers and primers. Releaser pheromones initiate immediate behavioral responses in insects upon reception, while primer pheromones cause physiological changes in an animal that ultimately result in a behavior response. Chemically identified releaser pheromones are of three basic types: those which cause sexual attraction, alarm behavior, and recruitment. Sex pheromones releasethe entire repertoire of sexual behavior. Thus a male insect may be attracted to and attempt to copulate with a n inanimate object that has sex pheromone on it. It appears that most insects are rather sensitive and selective for the sex pheromone of their species. Insects show far less sensitivity and chemospecificity for alarm pheromones. Alarm selectivity is based more on volatility than on uniquestructural features. Recruiting pheromones are used primarily in marking trails to food sources. Terrestrial insects lay continuous odor trails, whereas bees and other airborne insects apply the substances at discrete intervals. It appears that a complex pheromone system is used by the queen bee in the control of worker behavior. One well-established component of this system is a fatty acid,9-ketodecenoic acid, produced by the queen and distributed among the workers. This compound prevents the development of ovaries in the workers and inhibits their queen-rearing activities. In addition, the same compound is used by virgin queen bees as a sex attractant.
KEY WORDS insect attractants * sex attractants pheromones . releasers primers . behavior . chemical communication . terpenes . fattyalcohols . alarm . repellents . recruitment . territorial marking . odor

A L L LIVING THINGS are sources of volatile compounds which result from the metabolic activity of the organism. Slight genetic, dietary, and environmental differences

make it improbable that any two organisms produce the same blend of volatile organic compounds. This probably accounts for the fact that many animals areable to identify their young or members of their own group in large assemblages of other individuals. Groups of odorants are often species-specific and indicate sex or other intraspecies information. I t is not surprising, then, that in the complex interactions of animals with their environment they have come to depend to a large extent on olfactory perception for survival. Olfactory communicationis probably one of the oldest and, in some cases, the most efficient means of communication employed by animals. The power of olfactory communication has been witnessed by anyone who has seen how male dogs locate a bitch in heat or how the odor of a virgin female moth will draw males from great distances. Karlson and Butenandt have proposed the name “pheromone” for the chemical compounds thatenable members of the same species to communicate with each other (1). The term pheromone was derived from the Greek “pherein” (to carry) and “horman” (to excite, stimulate). Pheromones and hormones are distinctly different. Whereas hormones are produced in the endocrine glands and released internally to act upon a target tissue within the organism, pheromones are produced and discharged from glandswith external ducts. Pheromones function by influencing other members of the same . species, not the individual that produced them. Pheromones affect the central nervous system in two different ways. O n e class of compounds causes an immediate behavioral response upon reception, as in the case of the sex substances mentioned above. T h e second group of compounds has a delayed effect on...