Jeltje M. Stam

Plant Interactions with Multiple Insect Herbivores: From Community to Genes

Every plant is a member of a complex insect community that consists of tens to hundreds of species that belong to different trophic levels. The dynamics of this community are critically influenced by the plant, which mediates interactions between community members that can occur on the plant simultaneously or at different times. Herbivory results in changes in the plants morphological or chemical phenotype that affect interactions with subsequently arriving herbivores. Changes in the plants phenotype are mediated by molecular processes such as phytohormonal signaling networks and transcriptomic rearrangements that are initiated by oral secretions of the herbivore. Processes at different levels of biological complexity occur at timescales ranging from minutes to years. In this review, we address plant-mediated interactions with multiple species of the associated insect community and their effects on community dynamics, and link these to the mechanistic effects that multiple attacks have on plant phenotypes.

Community structure and abundance of insects in response to early‐season aphid infestation in wild cabbage populations

1. Changes in the arthropod community structure can be attributed to differences in constitutively expressed plant traits or those that change depending on environmental conditions such as herbivory. Early‐season herbivory may have community‐wide effects on successive insect colonisation of host plants and the identity of the initially inducing insect may determine the direction and strength of the effects on the dynamics and composition of the associated insect community.

Local dominance of exotic plants declines with residence time: a role for plant–soil feedback?

Exotic plant species have shown boom-bust patterns, first becoming invasive, but then over a longer time period declining in dominance. Exotic plant species may escape from their native enemies, but might become increasingly exposed to enemies in the new range as time since introduction increases. We investigated whether soil interactions could explain a pattern in the Netherlands where exotic plant species with a longer residence time are less dominant, by performing a plant soil feedback experiment. We found no evidence that plant-soil interactions explain this pattern.

Response of Brassica oleracea to temporal variation in attack by two herbivores affects preference and performance of a third herbivore

1. Plants are frequently under attack by multiple insect herbivores, which may interact indirectly through herbivore‐induced changes in the plants phenotype. The identity, order, and timing of herbivore arrivals may influence the outcome of interactions between two herbivores. How these aspects affect, in turn, subsequently arriving herbivores that feed on double herbivore‐induced plants has not been widely investigated.