<strong>A modified Munger cell for testing long-term effects of predator-induced stress on prey: an example using <em>Tyrophagus putrescentiae</em> (Acaridae) and its predator <em>Neoseiulus cucumeris</em> (Phytoseiidae)</strong>

Abstract

Predators can influence prey directly by consuming them, or indirectly by inducing stress to them. In previous studies, the exposure of leaves or containers to predators is short term and the replacement of such predator-exposed units for any long-term experiments is laborious. This study aims to establish a new method to enable continuous predator-induced stress to prey by using a modified Munger cell, with Tyrophagus putrescentiae and its predator predator Neoseiulus cucumeris as an example.

Level-dependent effects of predation stress on prey development, lifespan and reproduction in mites

“…Tyrophagus putrescentiae was chosen as the experimental species in this study, because it is a common species that is widespread on plants and in stored food and products (Fan and Zhang 2007), it has a relatively short life cycle, and its laboratory colony is easy to establish and inexpensive to maintain for experimental research. Neoseiulus cucumeris is a common predator of T. putrescentiae (Lee et al 2020) and was used as the predator to exert predation stress in this study (Wei and Zhang 2019). A previous study already showed in a two-choice test that T. putrescentiae preferred the cell not previously exposed to its predator N. cucumeris, which indicates that T. putrescentiae could respond to the cues deposited by its predator N. cucumeris (Wei and Zhang 2018).…”

“…predator cues deposited by one adult female predator in 24 h, because it is very time-consuming to expose leaves to predatory mites every day and to replace such predator-exposed units every day. Employing a different mite prey-predator system with the design of a set of two detachable cages separated by mesh screens, Wei and Zhang (2019) established a prey-predator system of T. putrescentiae and N. cucumeris that allowed the prey to be exposed to cues from the predator without being killed. This system Fig.…”

“…However, non-consumptive effects of predators, such as predation risks, are known to cause changes in the ecology, behaviour and physiology of the prey (Stoks 2001;Peckarsky et al 2002;Hawlena and Schmitz 2010;Skelhorn et al 2011;Zanette et al 2011;McCauley et al 2011;Clinchy et al 2013;Hermann and Thaler 2014;Gurr et al 2017) including prey life history traits such as development and reproduction in mite prey-predator systems (e.g. Grostal and Dicke 1999;Škaloudová et al 2007;Freinschlag and Schausberger 2016;Li and Zhang 2019;Wei and Zhang 2019). Studies on predation risks in the past mainly focused on the short-term effects on prey, such as development, behaviour and reproduction (e.g.…”

“…Long-term effects, such as effects on lifespan, are not often attempted because it is rather time consuming to apply predation stress for the whole lifespan of many animal species, and it is also difficult to separate the effects of direct killing from the indirect non-consumptive effects in many predator-prey systems (Li and Zhang 2019). In this study we focus on the effects of predation stress on lifespan using a mite predator-prey system which allows relatively easy application of predation stress of different levels over a long period (Wei and Zhang 2019).…”

“…A previous study already showed in a two-choice test that T. putrescentiae preferred the cell not previously exposed to its predator N. cucumeris, which indicates that T. putrescentiae could respond to the cues deposited by its predator N. cucumeris (Wei and Zhang 2018). Later, Wei and Zhang (2019) designed a modified setup consisting of two Munger cells separated by a screen for T. putrescentiae and N. cucumeris respectively. This design enabled easier application of long-term predation stress as well as changing the levels of predation stress.…”