Can the pheromones of predators modulate responses to herbivore‐induced plant volatiles?

Abstract

Biological control of greenhouse pests has been successfully developed and applied. In greenhouse crops, several entomophagous species (predators and parasitoids) are used simultaneously in the crop cycle. One important aspect of these crops, which represent modified ecosystems, is the interactions among complexes of species, including plants, phytophagous insects, and predators. The chemical relationships (semiochemicals: pheromones and kairomones) among these species likely play an important role in greenhouse crops; however, few studies have focused on these relationships. The aim of this study was to analyse the importance of semiochemicals. Three groups of laboratory trials were conducted with two predatory species: Nabis pseudoferus and Nesidiocoris tenuis (Hemiptera: Nabidae and Miridae, respectively). The results of the first group of trials indicated that the adult females of both species were more attracted to herbivore-induced plant volatiles (HIPVs) than they were to the control plants or plants with artificial damage. Based on the second group of trials, pheromones triggered an attraction in adult females of both species for conspecifics. Finally, based on the interactions of the adult females of the same species, pheromones changed or modulated the predatory responses to HIPVs. The implications of these results for the biological control of pest species in greenhouses are further discussed. Role of pheromones and kairomones in predatory insectsT. Cabello et al.

Opportunistic random searcher versus intentional search image user

“…Therefore, when cannibalism is rampant, it is reasonable to assume that, for the territorial cannibal predator, it is more beneficial to be an SIU that focuses on the non-conspecific prey than a RS because filial cannibalism can decrease the fitness of a female. In a Petri dish arena, Nabis uses visual and odour stimuli while searching and hunting 16 . Nabis can recognize its found possible prey by touching it with her antenna 42 .…”

“…The basic picture is motivated by the behaviours of certain predatory insects that practically forage continuously with the exception of egg laying. For example, Nabis pseudoferus Remane displays such behaviour 16 . Nabis eats all day; hence, the time required to lay eggs reduces the time available for predation.…”

“…The latter fact, in particular, will play an important role in the calculation of the numerical response. The female Nabis is territorial and uses visual and odour stimuli during hunting 16 . Nabis pseudoferus can be considered to be a non-omnivorous predator 17 .…”

Exploring the Kairomone-Based Foraging Behaviour of Natural Enemies to Enhance Biological Control: A Review

“…(Hymenoptera: Scelionidae), the parasitoid of Clavigralla species. However, not only herbivore pheromones play a role in the attraction of herbivore enemies, i.e., pheromones released by natural enemies also attract conspecific individuals seeking for mates (Ruther, 2013), and may modulate their responses to HIPVs (Cabello et al, 2017). For example, pheromones from males of the predator Nabis pseudoferus Remane (Hemiptera: Nabidae) attracted conspecific females and enhanced their responses to HIPVs from Rhopalosiphum padi (L.) (Hemiptera: Aphididae)-infested wheat plants, whereas pheromones from males of the mirid predator Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) attracted conspecific females but were found to reduce their attraction to the HIPVs (Cabello et al, 2017).…”