The Host Population

Authors: Castrillo, Louela

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 10/10/2017
Publication Date: 10/27/2017
Citation: Castrillo, L.A. 2017. The Host Population-Chapter 4. In: Hajek, A.E., Shapiro-Ilan, D.I., editors. Ecology of Invertebrate Diseases. Oxford, UK: John Wiley & Sons Ltd. p. 101-141. https://doi.org/10.1002/9781119256106.ch4.
DOI: https://doi.org/10.1002/9781119256106.ch4

Interpretive Summary:

Technical Abstract: The diversity and number of insects inhabiting variable habitats that are also rich with microorganisms, some of which are pathogenic, provide proof of the active and effective immune defenses insects employ. Studies on how insects defend themselves against microbial pathogens reveal multiple layers and facets of complementary mechanisms that range from structural barriers preventing pathogen entry to induction of antimicrobial peptides against pathogens in the gut and hemolymph to behavioral defenses that prevent exposure to pathogens or reduce pathogen inocula in the environment. The maintenance and induction of these defenses come at a cost, requiring trade-offs with insect life histories. But these defenses can be plastic and insects adjust their behavior and physiological responses to offset the accompanying costs of immunity. Considerable progress has been made in the last few decades in our understanding of insect immunity, with full genome sequence data of some insects providing the basis for examining mechanisms underlying physiological and behavioral components of immune responses to pathogens. The comprehension of the role of insect microbiome in insect defense also contributes to a holistic approach in these studies. While much still needs to be learned, the combination of two complementary approaches, studying host-pathogen interactions from specific and evolutionary points of view, will further facilitate studies of insect defenses, whether for our basic understanding or for applied purposes.