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ABSTRACT In this comprehensive exploration, we delve into the pivotal role of host plants in shaping the intricate interactions between herbivorous insects and their pathogens. Recent decades have seen a surge in studies that demonstrate that host plants are crucial drivers of the interactions between insects and pathogens, providing novel insights into the direct and indirect interactions that shape tri‐trophic interactions. These studies have built on a wide range of pathogens, from viruses to bacteria, and from protozoans to fungi. We summarise these studies, and discuss the mechanisms of plant‐mediated insect resistance to infection, ranging from the toxicity of plant chemicals to pathogens to enhancement of anti‐pathogen immune responses, and modulation of the insect's microbiome. Although we provide evidence for the roles of all these mechanisms, we also point out that the majority of existing studies are phenomenological, describing patterns without addressing the underlying mechanisms. To further our understanding of these tri‐trophic interactions, we therefore urge researchers to design their studies to enable them specifically to distinguish the mechanisms by which plants affect insect susceptibility to pathogens.
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Dynamic Roles of Insect Carboxyl/Cholinesterases in Chemical Adaptation
Insects have evolved several intricate defense mechanisms to adapt to their chemical environment. Due to their versatile capabilities in hydrolytic biotransformation, insect carboxyl/cholinesterases (CCEs) play vital roles in the development of pesticide resistance, facilitating the adaptation of insects to their host plants, and manipulating insect behaviors through the olfaction system. CCEs confer insecticide resistance through the mechanisms of qualitative or quantitative changes of CCE-mediated enhanced metabolism or target-site insensitivity, and may contribute to the host plant adaptation. CCEs represent the first odorant-degrading enzymes (ODEs) discovered to degrade insect pheromones and plant odors and remain the most promising ODE candidates. Here, we summarize insect CCE classification, currently characterized insect CCE protein structure characteristics, and the dynamic roles of insect CCEs in chemical adaptation.
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- Award ID(s):
- 2144082
- PAR ID:
- 10484687
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Insects
- Volume:
- 14
- Issue:
- 2
- ISSN:
- 2075-4450
- Page Range / eLocation ID:
- 194
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/insects14020194
