Amblyseius andersoni as a biological control agent of Tetranychus urticae on tomato

Abstract: Tomato glandular trichomes is an important physical and chemical defense barrier
against herbivores which however reduces the efficiency of several phytoseiid predators as
biological control agents. During the summer of 2022 an extended survey was conducted in
tomato fields through the continental Greece which resulted in the establishment of a field-collected population of Amblyseius andersoni. This is a phytoseiid species with well-documented efficiency as a biological control agent of the two-spotted spider mite Tetranychus urticae in several crops. In the present study, we tested the hypothesis that A. andersoni field-collected population has already been adapted to tomato defenses. Life-history traits such as juvenile developmental rate, oviposition, predation rate and survival of individuals of the field-collected population were recorded on tomato leaves. Mean daily prey consumption was approximately ten spider mite larvae per adult female, whereas the respective daily oviposition rate was approximately 1.5 eggs per female. Survival of both juveniles and adult females was high whereas the provision of Typha angustifolia L. pollen resulted in an increase in the daily oviposition rate and the juvenile survival. Small-scale laboratory experiments, focusing on the evaluation of the effects of different initial prey: predator density ratios, as well as the role of pollen provisioning on the biocontrol efficacy of the two spotted spider mite are in progress.