Diapause Factor-Producing Cells in the Suboesophageal Ganglion of the Silkworm, Bombyx mori L.

STUDIES ON THE DIAPAUSE FACTOR‐PRODUCING CELLS IN THE SUBOESOPHAGEAL GANGLION OF THE SILKWORM, BOMBYX MORI L.

“…3 and 4). As reported previously (FUKUDA and TAKEUCHI, 1967), the cells were situated toward the ventral side of the suboesophageal ganglion a t the level about two-thirds from its anterior end, being laden with a large amount of azocarminophilic material in the cytoplasm. The cells were readily distinguishable owing to the staining property of neurosecretory material, even a t a low magnification in moths as well as in pupae ( Fig.…”

“…Furthermore, moths emerging from pupae deprived of suboesophageal ganglion but given an implant of a small piece of the ganglion containing DF cells laid diapause eggs together with nondiapause ones, like those developed from similarly operated pupae receiving a transplant of suboesophageal ganglion in toto. Transplantation of any other part of the suboesophageal ganglion was without effect in this respect (FUKUDA and TAKEUCHI, 1967 ).…”

“…106" and t h e Chinese race "Taizo" a r e bivoltine, most of experimental studies on diapause hitherto performed (FUKUDA, 1952(FUKUDA, , 1962(FUKUDA, a, b, 1963, FUKUDA a n d TAKEUCHI, 1967) have been conducted with these hybrids. Nondiapause egg-producers (referred to as ND) and diapause egg-producers ( D ) were obtained from eggs incubated at 15OC in t h e dark and at 27OC under illuminatlon.…”

“…Whether the silkworm they studied was diapause egg-producer or nondiapause egg-producer is not known from their paper. In a previous paper (FUKUDA and TAKEUCHI, 1967), we have presented experimental evidence showing that the DF cells are the actual source of diapause factor responsible for the production of diapause eggs. The findings reported in this paper are in support of the previous conclusion.…”

Functional Differentiation of Neurosecretory Cells with Immunoreactive Diapause Hormone and Pheromone Biosynthesis Activating Neuropeptide of the Moth, Bombyx mori

“…4). Fukuda and Takeuchi (1967) found a pair of somata of neurosecretory cells localized along the ventral midline of SG and suggested that these cells might be the source of a diapausing hormone (DH) because females laid non-diapause eggs when they had the cells surgically removed at the earliest pupal stage. The posterior cells examined in the present study may correspond to the neurosecretory cells because of the similarity in morphological and functional natures.…”