Effects of temperature on mating duration, sperm transfer and remating frequency in Callosobruchus chinensis

Insect body temperature is usually determined by ambient temperature. Therefore, most biochemical and physiological processes underlying behavioural patterns are temperature dependent. Mating duration is also dependent on temperature, and therefore temperature should influence on sperm transfer and female remating frequency. In the adzuki bean beetle, Callosobruchus chinensis, we found negative relationships between ambient temperature and mating duration, sperm transfer and sperm transfer duration. Female remating frequency at lower temperature (17 degrees C) was lower than at other temperatures (25 degrees C and 33 degrees C). The physiological and behavioural significance of these results is discussed. The number of ejaculated sperm was significantly lower at 33 degrees C than at 17 degrees C; the effect of temperature on sperm transfer is discussed in relation to the intensity of female refusal behaviour directed against males.