Chemosterilizing Southern Corn Rootworm Beetles with Apholate

When both sexes of Diabrotica undecimpunctata howardi Barber adults were treated with solutions containing 50—100 ppm apholate by feeding or contact, the eggs per female and the viability of the eggs decreased. The ovaries of treated females were smaller and/or the ovarioles of the treated females were fewer and smaller. The tests of treated males showed no consistent effect and activity of the sperm seemed normal, but the accessory gland which is responsible for secreting seminal fluid was degenerated. Thus, the decrease in viability when males were treated probably was caused by failure of the male to transmit sperm to the female during copulation because of a lack of seminal fluid.