Tritrophic Interactions among Arthropod Natural Enemies, Herbivores and Plants Considering Volatile Blends at Different Scale Levels

Abstract

Herbivore-induced plant volatiles (HIPVs) are released by plants upon damaged or disturbance by phytophagous insects. Plants emit HIPV signals not merely in reaction to tissue damage, but also in response to herbivore salivary secretions, oviposition, and excrement. Although certain volatile chemicals are retained in plant tissues and released rapidly upon damaged, others are synthesized de novo in response to herbivore feeding and emitted not only from damaged tissue but also from nearby by undamaged leaves. HIPVs can be used by predators and parasitoids to locate herbivores at different spatial scales. The HIPV-emitting spatial pattern is dynamic and heterogeneous in nature and influenced by the concentration, chemical makeup, breakdown of the emitted mixes and environmental elements (e.g., turbulence, wind and vegetation) which affect the foraging of biocontrol agents. In addition, sensory capability to detect volatiles and the physical ability to move towards the source were also different between natural enemy individuals. The impacts of HIPVs on arthropod natural enemies have been partially studied at spatial scales, that is why the functions of HIPVs is still subject under much debate. In this review, we summarized the current knowledge and loopholes regarding the role of HIPVs in tritrophic interactions at multiple scale levels. Therefore, we contend that closing these loopholes will make it much easier to use HIPVs for sustainable pest management in agriculture.

Increasing intraspecific plant chemical diversity at plot and plant level affects herbivorous, predatory, and pollinating arthropod communities

“…These findings suggest that plant chemistry differentially affects arthropod groups based on their interaction with the plant. While plant chemistry significantly influences directly interacting organisms like flower visitors, it does not show a similar significant impact on indirectly interacting organisms such as predators and ants (Ali et al, 2023).…”

1-nonene plays an important role in the response of maize-aphid-ladybird tritrophic interactions to nitrogen

“…Tritrophic interactions are among the most important components of all terrestrial ecosystems ( Turlings and Erb, 2018 ). When under attack by herbivores, some plants recruit a third trophic level, which increases the plant’s attractiveness to the natural enemies of herbivores, and these organisms then provide the plant protection from herbivory and reduce plant damage ( Hiltpold et al., 2011 ; Ali et al., 2023 ). Since evidence for an active role of herbivore-damaged plants in recruiting natural enemies of herbivores was first reported, an increasing number of different species of plants have been found to attract a range of herbivore enemies after an herbivore attack, including insect predators, parasitoids, predatory mites, nematodes, and birds ( Clavijo et al., 2012 ; Meijer et al., 2023 ).…”

Volatiles from cotton aphid (Aphis gossypii) infested plants attract the natural enemy Hippodamia variegata

“…HIPVs are a diverse group of volatile organic compounds (VOCs) that released from leaves, flowers, and fruits into the atmosphere and from roots into the soil. They are synthesized from a variety of precursors, including fatty acids, amino acids, and terpenes ( Dicke and Baldwin, 2010 ; Ali et al., 2023 ). They play important roles in plant indirect defense by attracting natural enemies of herbivores in various ways.…”