This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Skopik, S. D. Articles by Takeda, M. Search for Related Content PubMed PubMed Citation Articles by Skopik, S. D. Articles by Takeda, M. Social Bookmarking                         What's this?

Diapause Induction and Termination: North-South Strain Differences in Ostrinia nubilalis

School of Life and Health Sciences, University of Delaware, Newark, Delaware 19716

Makio Takeda

School of Life and Health Sciences, University of Delaware, Newark, Delaware 19716

Diapause induction and termination responses of a northern strain (Minnesota [MN]) of Ostrinia nubilalis were compared with those of a southern strain (Georgia [GA]). A ther moperiod in constant light (12 hr at 25°C alternating with 12 hr at4°C) failed to induce diapause in GA larvae, but approximately 50% diapause induction was observed in the MN population. Moreover, the 50% of MN larvae that continued their development (i.e., underwent pupation and adult development) did so at a slower rate, as measured by days to pupation, than GA larvae.

In the laboratory, diapausing MN larvae responded more slowly to the optimal light-dark (LD) cycle for terminating diapause, LD 16:8, than did GA larvae. In the field MN populations are univoltine (i.e., are characterized by one generation per year). A delayed termination response in the spring, coupled with a longer critical daylength for diapause induction as daylength decreases during late summer (earlier diapause) restricts the time during which development can occur as contrasted with GA populations. In addition, it is postulated that these two phenomena, coupled with a possibly slower growth rate in the MN insects as revealed under laboratory conditions, may collectively represent the basis for univoltinism in the field.

Journal of Biological Rhythms, Vol. 2, No. 1, 13-22 (1987)
DOI: 10.1177/074873048700200102


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				M. V. Nunes and D. Saunders Photoperiodic Time Measurement in Insects: A Review of Clock Models J Biol Rhythms, April 1, 1999; 14(2): 84 - 104. [Abstract] [PDF]