Peripheral and behavioral plasticity of pheromone response and its hormonal control in a long-lived moth

Abstract

SUMMARYReproductive success in many animals depends on the efficient production of and response to sexual signals. In insects, plasticity in sexual communication is predicted in species that experience periods of reproductive inactivity when environmental conditions are unsuitable for reproduction. Here, we study a long-lived moth Caloptilia fraxinella (Ely) (Lepidoptera: Gracillariidae) that is reproductively inactive from eclosion in summer until the following spring. Male sex pheromone responsiveness is plastic and corresponds with female receptivity. Pheromone response plasticity has not been studied in a moth with an extended period of reproductive inactivity. In this study, we ask whether male antennal response and flight behavior are plastic during different stages of reproductive inactivity and whether these responses are regulated by juvenile hormone. Antennal response to the pheromone blend is significantly reduced in reproductively inactive males tested in the summer and autumn as compared with reproductively active males tested in the spring. Reproductively inactive autumn but not summer males show lower antennal responses to individual pheromone components compared with spring males. Treatment with methoprene enhances antennal response of autumn but not summer males to high doses of the pheromone blend. Behavioral response is induced by methoprene treatment in males treated in the autumn but not in the summer. Plasticity of pheromone response in C. fraxinella is regulated, at least in part, by the peripheral nervous system. Antennal and behavioral response to pheromone differed in reproductively active and inactive males and increased with methoprene treatment of inactive males.

A Biologically Active Analog of the Sex Pheromone of the Emerald Ash Borer, Agrilus planipennis

“…In the present work, we show that the saturated lactone analog (hereafter called analog), dodecan-12-olide, also has biological activity in terms of electrophysiological and olfactometer responses and trapping efficacy, indicating not only function but also plasticity in pheromone structure, perception, and response (Lemmen and Evenden 2009). …”

Involvement of the G-Protein-Coupled Dopamine/Ecdysteroid Receptor DopEcR in the Behavioral Response to Sex Pheromone in an Insect

“…JH influences the age-dependent behavioral and central nervous responses to sex pheromone in the moth, Agrotis ipsilon [13], [14]. JH also modulates behavioral and peripheral pheromone responses in the long-lived moth Caloptilia fraxinella [9]. The role of 20 E in the control of sex pheromone responses is less studied.…”

JH biosynthesis by reproductive tissues and corpora allata in adult longhorned beetles, Apriona germari

“…Among its important roles, JH can influence mating itself, in some insect species, through regulation of sex pheromone biosynthesis (Lemmen and Evenden, 2009). However, Bober et al (2010) recently reported that JH does not influence the expression of the gene encoding the pheromone biosynthesis activating neuropeptide receptor (PBAN-R) in the moth Helicoverpa armigera.…”