Photoperiodic Implications on the Pupal Ecdysis in the Silkworm, Bombyx Mori L. (Pm x Nb4D2)

  • N. Sivarami Reddy
  • T. Pavan Kumar
  • P. Murali Mohan
  • K. Sasira Babu
Research Article


Pupation patterns, viz. larval ripening, pharate pupal and pupal formation were diurnally predominant in the silkworm, Bombyx mori L. (PM x NB4D2), under different photoperiodic conditions. Under continuous light (LL), the rhythm damped-out. Upon circular statistical treatment of the data, the peaks expressed two distinct modes short day and long day resultant groups and these phenomena are distinct for pharate pupal formation. Duration between larval ripening and pharate pupal formation, as also between pharate pupal and pupal formation was influenced by different light/dark conditions. Duration between larval ripening and pupal formation was significantly (P < 0.05) less under LD 11:13 as compared to LD 12:12.

Key Words

Photoperiod pupal ecdysis Bombyx mori 


On a trouvé que, sous les conditions photopériodique variables, les modèles de pupation—c’est -à-dire, la maturation larvale, la formation pharate-pupale aussi que la formation pupale—étaient prédominant pendant le jour, en cas du vers à soie, Bombyx mori. Sous l’illumination continue, le rythme s’est aplati. Quand les données expérimentales ont été soumis à une traitement statistique circulaire, les pics se sont manifestés comme deux modes distincts, c’est-à-dire, les groupes résultantes du jour court et du jour long respectivement; ce phénomène est distinct pour la formation pharate-pupale. La duration temporale entre la maturation larvale et la formation pharate-pupale, et aussi celle entre la formation pharate-pupale et la formation pupale étaient affectées par les proportions variables des périodes lumineuses et sombres. La période entre la maturation larvale et la formation pupale étaient significativement (P < 0.05) plus court pour une proportion liumineux/sombre égal à 11:13 que pour la dite proportion égal à 12:12.


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Copyright information

© ICIPE 1993

Authors and Affiliations

  • N. Sivarami Reddy
    • 1
  • T. Pavan Kumar
    • 1
  • P. Murali Mohan
    • 1
  • K. Sasira Babu
    • 1
  1. 1.Department of ZoologySri Venkateswara UniversityTirupatiIndia

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