Studies on mutualistic relationship between Saisettia formicarii and an ant species (Crematogaster dorhni?) with special reference to entomogenous fungus Aschersonia aleyrodis

Authors

  • S. Debnath
  • B.K. Barthakur
  • Karan Singh

Abstract

A mutualistic relationship between an ant species (Crematogaster dorhni) and scale insect (Saisettia formicarii) pests of tea was observed in experimental tea areas of Tocklai. The population of scale insects and ants remarkably increased due to mutualistic association. Initially ants protected the colony of S. formicarii from natural enemies and removed waxy coatings and other debris. Ants were also responsible for transferring eggs and nymphs of scale insects to different parts of tea plant. Foliar application of insecticides intended for the control of Helopeltis increased the mortality of ants population and increased subsequent parasitization of scale insects by a parasitoid. An entomogenous fungus Aschersonia aleyrodis was found to infect the colony of scale insects with varying degrees. It was found that ants were not infected by fungus. Insecticidal removal of ants did not reduce the infection level by entomogenous fungus, A. aleyrodis. Ants deprived of honey due to infection of scale insects induced by fungus, moved away to top layers of the canopy to attend aphids. It was inferred that the association of entomogenous fungus A. aleyrodis significantly checked population of scale insects in tea field.

Published

22.09.2021

Issue

Section

Research Papers