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The mature eggs of Plodia interpunctella were found to contain four major polypeptides. These yolk polypeptides (YPs) were found to have approximate molecular weights of 153,000 daltons (YP1), 69,000 daltons (YP2), 43,000 daltons (YP3), and 33,000 daltons (YP4) as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). In addition, we found YP1 was resolved by a 5% polyacrylamide gel into two separate polypeptides of 153,000 and 147,000 daltons. All of the YPs could be labeled in vivo or in vitro with [35S]-methionine. Yolk peptide 1 and YP3 were synthesized by fat body of pharate adult and adult females and secreted into the hemolymph. Yolk peptide 2 and YP4 were synthesized and secreted into incubation medium by ovaries that contained vitellogenic oocytes, but these polypeptides were not found in the hemolymph. Fat bodies of males synthesized and secreted an immunoprecipitable polypeptide similar to YP3 as well as immunoprecipitable polypeptides larger than 200,000 daltons that had no counterparts in the oocytes. Peptide mapping by protease digestion showed each YP to be cleaved into unique fragments, suggesting that no precursor-product relationship exists between the YPs. Ion exchange chromatography and gel permeation chromatography separated that yolk proteins into two groups with approximate molecular weights of 462,000 and 264,000 daltons. By resolving these peaks on SDS-PAGE, it was found that YP1 and YP3 formed the 462,000-dalton yolk protein and YP2 and YP4 formed the 264,000-dalton yolk protein.

Allonemobius fasciatus DeGeer maintains a univoltine life cycle with an embryonic diapause over an altitudinal gradient of as large as 1100 m. Hatching time differs by more than 1.5 months between the highest and lowest altitudes studied. Little or no genetic difference was detected between populations from different altitudes when physiological traits such as diapause intensity, postdiapause development, and nymphal development were compared in the laboratory. Photoperiod influenced the duration of the nymphal stage and the number of instars, compensating for the shorter growing season at higher elevations. This photoperiodic regulation of nymphal development would also serve as a mechanism synchronizing adult emergence within a population of this species.

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