Co-Authors:
Kehat, M., Div. of Entomology, ARO, The Volcani Center, Bet Dagan, Israel
Genizi, A., Div. of Statistics and Experiment Design, ARO, The Volcani Center, Bet Dagan, Israel
Greenberg, S., Div. of Entomology, ARO, The Volcani Center, Bet Dagan, Israel
Abstract:
The aim of this investigation was to clarify whether pheromone traps could provide a reliable tool for early detection of a S. littoralis adult population and for indicating infestation by its larvae in the field. The aggregated pattern of distribution of adults is indicated by the fit of data to Taylor's Power Law or to the negative binomial distribution. However, the relatively high k values obtained indicate that S. littoralis adults are only slightly aggregated and sometimes almost randomly distributed. Trap position in the field and number of traps per area unit affected size of catches in both female-baited and synthetic-pheromone-baited traps. No relationship between size of catches and temperature, wind velocity or moon phase was detected. Variations in size of catches among traps was not affected much by the baited females. Pheromone traps proved to be a reliable tool for estimating fluctuations in population density and for indicating adult peaks. However, no correlation between male catches and infestation by larvae in the experimental plots was found. Pheromone traps may serve only as a warning device indicating the possibility of potential attack due to an increase in adult population level. Mercury vapor light traps were inferior to pheromone traps in detecting changes in S. littoralis population densities. Synthetic pheromone ("Litlure") was somewhat less efficient in attracting males than virgin females; however, it is suitable for detecting fluctuations in the S. littoralis adult population. © 1975 Springer Science + Business Media B.V.