Differential Response of Herbivores
to Plant Defence
4
Martin Volf
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
2 Roles of Insect Specialization in Their Response to Host Plant Defences . . . . . . . . . . . . . . . . . . 79
3 Tolerance and Adaptations of Specialized Insect Herbivores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
4 Nutrients, Natural Enemies, and Induced Defences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
5 Feeding Guilds and Their Response to Host Plant Defences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
6 Roles of Insect Morphology and Physiology in the Response to Host Plant Traits . . . . . . . . 88
7 Implications for Evolution of Host Plant Defences and Insect Diversity . . . . . . . . . . . . . . . . . . . 90
8 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Abstract
The differential response of insect herbivores to plant traits is one of the mechanisms promoting diversity and specificity of insect-plant interactions. The response
differs mainly among generalist insects on the one hand and specialized or adapted
insects on the other hand. While generalists are often strongly affected by toxic
defences of their hosts, specialists have evolved various adaptations to overcome
such defences. These adaptations include tolerance, detoxification, or sequestration
of secondary metabolites of the host. In addition, behavioral adaptations help
herbivores to avoid particularly potent defences. The response of herbivores is
also tightly linked to their feeding mode (i.e., herbivore guild), physiology, metabolism, or size. The resulting specificity of interactions gives rise to diversification of
host defences as no single trait can provide an efficient defence against diverse
communities of insects. The diversification of host defences then seems to be one of
the key factors promoting diversity of insects in a reciprocal way.
M. Volf (*)
Molecular Interaction Ecology Group, German Centre for Integrative Biodiversity Research (iDiv)
Halle-Jena-Leipzig, Leipzig, Germany
e-mail: martin.volf@idiv.de; volf@entu.cas.cz
© Springer Nature Switzerland AG 2020
J.-M. Mérillon, K. G. Ramawat (eds.), Co-Evolution of Secondary Metabolites,
Reference Series in Phytochemistry, https://doi.org/10.1007/978-3-319-96397-6_38
77
to Plant Defence
4
Martin Volf
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
2 Roles of Insect Specialization in Their Response to Host Plant Defences . . . . . . . . . . . . . . . . . . 79
3 Tolerance and Adaptations of Specialized Insect Herbivores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
4 Nutrients, Natural Enemies, and Induced Defences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
5 Feeding Guilds and Their Response to Host Plant Defences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
6 Roles of Insect Morphology and Physiology in the Response to Host Plant Traits . . . . . . . . 88
7 Implications for Evolution of Host Plant Defences and Insect Diversity . . . . . . . . . . . . . . . . . . . 90
8 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Abstract
The differential response of insect herbivores to plant traits is one of the mechanisms promoting diversity and specificity of insect-plant interactions. The response
differs mainly among generalist insects on the one hand and specialized or adapted
insects on the other hand. While generalists are often strongly affected by toxic
defences of their hosts, specialists have evolved various adaptations to overcome
such defences. These adaptations include tolerance, detoxification, or sequestration
of secondary metabolites of the host. In addition, behavioral adaptations help
herbivores to avoid particularly potent defences. The response of herbivores is
also tightly linked to their feeding mode (i.e., herbivore guild), physiology, metabolism, or size. The resulting specificity of interactions gives rise to diversification of
host defences as no single trait can provide an efficient defence against diverse
communities of insects. The diversification of host defences then seems to be one of
the key factors promoting diversity of insects in a reciprocal way.
M. Volf (*)
Molecular Interaction Ecology Group, German Centre for Integrative Biodiversity Research (iDiv)
Halle-Jena-Leipzig, Leipzig, Germany
e-mail: martin.volf@idiv.de; volf@entu.cas.cz
© Springer Nature Switzerland AG 2020
J.-M. Mérillon, K. G. Ramawat (eds.), Co-Evolution of Secondary Metabolites,
Reference Series in Phytochemistry, https://doi.org/10.1007/978-3-319-96397-6_38
77