Can plant-natural enemy communication withstand disruption by biotic and abiotic factors?

Abstract

The attraction of natural enemies towards herbivore-induced plant volatiles is a well-documented phenomenon. However, the majority of published studies are carried under optimal water and nutrient regimes and with just one herbivore. But what happens when additional levels of ecological complexity are added? Does the presence of a second herbivore, microorganisms, and abiotic stress interfere with plant-natural enemy communication? or is communication stable enough to withstand disruption by additional biotic and abiotic factors?Investigating the effects of these additional levels of ecological complexity is key to understanding the stability of tritrophic interactions in natural ecosystems and may aid to forecast the impact of environmental disturbances on these, especially in climate change scenarios, which are often associated with modifications in plant and arthropod species distribution and increased levels of abiotic stress.This review explores the literature on natural enemy attraction to herbivore-induced volatiles when, besides herbivory, plants are challenged by additional biotic and abiotic factors.The aim of this review was to establish the impact of different biotic and abiotic factors on plant-natural enemy communication and to highlight critical aspects to guide future research efforts.

Keywords: climate change; herbivore‐induced plant volatiles; multitrophic interactions; natural enemies; parasitoids; predators.

Figure 1

Multiple variables affect plant volatile emissions and natural enemy (NE) responses. The bullet points highlighted in red are critical for the occurrence of a particular plant–herbivore–natural enemy interaction under natural conditions. The points in blue correspond to additional factors having an impact on volatile emission and the use of volatile cues by natural enemies