Research Fellows Directory
Dr Mor Salomon-Botner
The study examines the nutritional mechanisms involved in predation of the predatory omnivorous mite Amblyseius swirskii (Acarina: Phytoseiidae) in order to improve its efficacy as a biological control agent. To this end, I combine in my research several disciplines in ecology. Basic ecological theory on omnivory, predator-prey interaction and trophic level interactions are employed. This knowledge is placed in the context of biological control, where the predator is confined to a specific combination and availability of pest species in the crop. Lastly, I integrate nutritional ecology theory as a novel tool to understand the mechanisms behind omnivory and predation. This involves the use of a state-space modeling approach (i.e. the Geometric Framework’) to explore how the animal balance multiple nutrient needs in a variable nutritional environment. Animals require a specific balance in their intake of nutrients and energy to develop, survive and reproduce. The nutritional requirements of an animal constitute the ‘nutritional target’ representing the optimal level of various nutrients needed by its tissues. To reach this nutritional target, the mite has to optimize its nutrient intake either by incorporating plant material in its diet (i.e. omnivory), and/or by differentially extracting nutrients from the prey, as was recently shown for spiders. Lab experiments on the suitability of prey and plant food sources to the mite and nutritional analyses of the food, the ‘nutritional target’ of the mite can be found and used to improve its pest control.
Understanding of the role of nutrient balancing mechanisms on predator-prey population dynamics promises to yield novel approaches to biological pest control. For example, predators with a well-defined nutrient deficiency could be released in the field so that their pest intake is maximized to redress their nutritional deficiency. Another approach could involve the provisioning of food supplements to support omnivore survival before pest populations surge. Producers of biological control agents show great interest in commercial supply of food supplements to be marketed in combination with mass-reared biocontrol agents (a $3 billion/year market worldwide). The proposed research examines the impact of such non-prey food supplements on pest suppression.