Post‐spray effects of an aerial application of fenitrothion on the pine beauty moth, Panolis flammea (Denis & Schiffermüller)

Abstract

Panolis flammea that had survived an aerial spraying programme of fenitrothion were compared in a series of laboratory experiments with moths that had not been within the sprayed area, to assess the effects of sub‐lethal spray application on various life history parameters. Emergence success was not significantly different between the two treatments and the sex ratio in both cases approximated 1:1. The bionomics of moths surviving in the sprayed plots were different in several respects from those taken from unsprayed plots. The former emerged from pupae later, had lower levels of fecundity and a longer pre‐oviposition period. Females from sprayed plots were also heavierthan males and their weight was positively correlated with fecundity, whereas neither of those traits were shown by unsprayed moths. A number of other bionomic traits were not significantly different in sprayed or unsprayed groups. Analysis of the population growth rates of P. flammea from areas of the forest where control was either ineffective or effective, revealed no significant differences. The implications of these results for the population dynamics of P. flammea are discussed.

Keywords:

• Panolis flammea
• post‐spray effects
• fecundity
• life span
• forestry