Movement of Eupyrene Sperm Bundles from the Testis and Storage in the Ductus Ejaculatoris Duplex of the Male Pink Bollworm:1 Effects of Age, Strain, Irradiation, and Light2

Abstract
When pink bollworms, Pectinophora gossypiella (Saunders), were maintained in a 12:12 light-dark regimen, the eupyrene sperm bundles showed a pronounced rhythm in descending from the testis to the duplex region: they descended from the testis into the upper vas deferens starting at the 3rd or 4th h of the dark period; then with the onset of the light cycle, they descended into the seminal vesicles, accumulated there for the 1st half of the light period, and were transferred to the duplex region of the ejaculatory duct. The same rhythm was maintained in severed abdomens. Although laboratory-reared and native strains varied considerably in the number of sperm bundles stored in the duplex, ca. 10–20 entered the duplex each day and accumulated there until the male mated. After mating, the duplex region was emptied of sperm bundles, but mating did not increase the rate or number of sperm bundles that descended to the duplex. Rearing pink bollworm pupae in constant light significantly reduced the number of sperm bundles that were transferred to the duplex. Irradiating newly-emerged males with 30 krad of gamma irradiation had no effect on the number of sperm bundles found in the duplex of 4-day-old males but, in 2 strains studied, 8-day-old males had a reduced number of sperm bundles.