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Entomophaga

, Volume 30, Issue 3, pp 279–286 | Cite as

Feeding by adultCyrtobagous salviniae onSalvinia molesta under different regimes of temperature and nitrogen content and the effects on plant growth

  • I. W. Forno
  • A. S. Bourne
Article

Abstract

Feeding by adultCyrtobagous salviniae was not influenced by the concentration of nitrogen in the buds ofSalvinia molesta. The time spent feeding on a bud was dependent on temperature and the rate of bud development because adults abandoned a bud when it started to open. When 2 pairs of adults were placed on a partially developed bud at 35°C, bud development was stopped. Plants attacked by weevils for 3 days were heavier than insect-free plants but after another 10 days without further attack, growth of unattached plants was significantly greater.

Key-words

Cyrtobagous feeding temperature nutrition Salvinia molesta nitrogen 

Résumé

La prise de nourriture par les adultes deCyrtobagous salviniae n'était pas influencée par la concentration d'azote dans les bourgeons deSalvinia molesta. Le temps mis pour's alimenter sur un bourgeon dépendait de la température et de la vitesse de développement du bourgeon parce que les adultes abandonnaient un bourgeon quand il commençait à s'ouvrir. Quand 2 paires d'adultes furent placées sur un bourgeon partiellement développé 35°C, le développement du bourgeon était arrêté. Les plants attaqués par les charançons durant 3 jours furent plus gros que les plants indemnes, mais après 10 jours de plus sans attaque ultérieure, la croissance des plants indemnes était significativement plus forte.

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References

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Copyright information

© Lavoisier Abonnements 1988

Authors and Affiliations

  • I. W. Forno
    • 1
  • A. S. Bourne
    • 2
  1. 1.Division of EntomologyCSIROAustralia
  2. 2.Division of Mathematics and Statistics, Long Pocket LaboratoriesCSIROAustralia

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