Role of the bursa copulatrix in egg maturation and reproductive behavior of the tobacco hawk moth, Manduca sexta

Summary

Stretching of the bursa copulatrix by an artificial spermatophore of a polymer plastic caused increased egg maturation to the level normally seen only in mated female Manduca sexta. The input from the stretched bursa was relayed anteriorly via dendrites that arborised over the length of the bursa copulatrix, then entered the terminal abdominal ganglion via the 8th ventral nerve. Such mechanical stretching however did not cause the normal switch from virgin calling behavior to mated ovipositional behavor. Instead the cessation of calling behavior was mediated by some interaction of sperm and/or seminal fluids with the bursa since implantation of bursae without spermatophores from mated females into virgin females turned off this behavior. These implants failed to initiate mated ovipositional behavior.

Keywords:

• egg maturation
• reproductive behavior
• bursa copulatrix
• Manduca sexta