Insects destroy inestimable amount of crops each year. Spraying insecticides to control pests has raised serious concerns because of ancillary effects upon other species, especially humans. Pheromones are chemical signals that individuals release into the external environment that affect the behavior and/or physiological states of other individuals. In insects, pheromones are one of the major forms of communication. Since these chemical signals provide a non-invasive method for control of insect populations, the use of pheromones as an integral part of integrated pest management programs for many lepidopterous pest species is of considerable importance and interest. One of the prominent features of this communication in insects is that release of the pheromone by females and response by males occurs during a species-characteristic time. This temporal synchrony assures that males and females will be able to locate one another at a time when environmental conditions ar most favorable for mating. Drs. Linn and Roelofs' research program is aimed at understanding the mechanisms by which these chemical signals are used by insects. In this project, they will determine how male insects can tell time so that they are responsive to the chemical signals when the females are releasing it. They will focus on the biogenic amines octopamine, serotonin and melatonin. Octopamine and serotonin were selected because their previous work indicates that these two amines affect both the timing and the sensitivity of males to pheromones. Melatonin is an excellent candidate given the significant role of this hormone in the regulation of circadian-regulated activates in vertebrates, including humans. Drs Linn and Roelofs will determine the relationship between these biogenic amines, behavior and the neural regions associated circadian activity. The results from these basic biological studies provide fundamental information about invertebrate and vertebrate neurobiology. Moreover, their research will aid in the continuing development of pheromone attractants for practical agricultural use.
