Conny Schütte1, Peter van Baarlen1,2, H. Dijkman1, Marcel Dicke1
1Laboratory of Entomology, Wageningen Agricultural University, P.O. Box 8031, 6700 EH, Wageningen, The Netherlands
2Laboratory of Genetics, Wageningen Agricultural University, P.O. Box 8031, 6700 EH Wageningen, The Netherlands
Tóm tắt
AbstractAdult females of the predatory mite Phytoseiulus persimilis Athias‐Henriot are strongly attracted to infochemicals released by plants infested with their prey, the two‐spotted spider mite (Tetranychus urticae Koch), thereby effectively locating their prey. However, we found a consistently lower degree of attraction to these infochemicals for a population of P. persimilis, which is called non‐responding population. Here we demonstrate that this low degree of attraction is a contagious phenomenon and that it cannot be explained by differences in abiotic conditions, physiological state and experience of predators or by genetic differences between predator populations. Female predators exposed to dead conspecifics of the non‐responding population and their products showed a lower degree of attraction to plant odours and a higher mortality than predators exposed to products of a living conspecific of the non‐responding population. This was true 6–7 days after contact with dead conspecifics and their products whereas 2 days after contact no effects were detected. The present results are discussed in view of our hypothesis that the change in foraging behaviour as well as the high mortality rate are symptoms of a contagious disease affecting the non‐responding population.
