DOI: 10.5061/dryad.pnvx0k6n3
title: Plant defence to sequential attack is adapted to prevalent herbivores

description: Plants have evolved plastic defence strategies to deal with uncertainty of
 when, by which species and in which order attack by herbivores will take
 place. However, the responses to current herbivore attack may come with a
 cost of compromising resistance to other, later arriving herbivores. Due
 to antagonistic cross-talk between physiological regulation of plant
 resistance to phloem-feeding and leaf-chewing herbivores, the feeding
 guild of the initial herbivore is considered to be the primary factor
 determining whether resistance to subsequent attack is compromised. We
 show that, by investigating 90 pair-wise insect-herbivore interactions
 among ten different herbivore species, resistance of the annual plant
 Brassica nigra to a later arriving herbivore species is not explained by
 feeding guild of the initial attacker. Instead, the prevalence of
 herbivore species that arrive on induced plants as approximated by three
 years of season-long insect community assessments in the field explained
 cross-resistance. Plants maintained resistance to prevalent herbivores in
 common patterns of herbivore arrival and compromises in resistance
 especially occurred for rare patterns of herbivore attack. We conclude
 that plants tailor induced defence strategies to deal with common patterns
 of sequential herbivore attack and anticipate arrival of the most
 prevalent herbivores.
description: Plant mediated interactions and insect resistance: 
 Plants were induced with one of ten different herbivore species
 for one week, cross resistance/susceptibility was measured for each of the
 ten herbivore species. Resistance was measured in terms of aphid
 population growth or caterpillar weight gain. Field
 observations on insect prevalence: Field occurance of
 species interactions was based on weekly observations of insect presence
 on <em>Brassica nigra</em> in three years. Interaction
 frequency represents the percentage of <em>B. nigra</em>
 plants in the field experiments on which the inducing herbivore species
 was observed before or at the same time as the receiving herbivore
 species.  Plant gene experession:
 We characterized by the expression of <i>LIPOXYGENASE 2
 (LOX2)</i> as marker gene for the JA pathway and
 <i>PATHOGENESIS-RELATED PROTEIN 1 (PR1) </i>as a marker for
 the SA pathway by Real Time PCR. Leaf samples were taken at 24 or 96 hours
 after plants were infested with herbivores. For each herbivore treatment
 and time point, we sampled the youngest fully developed leaf on which
 herbivores had been released from five plants and combined these samples
 to one biological replicate per herbivore species. We repeated our
 experiment 10 times, obtaining 10 biological replicates per herbivore
 species.
description: Our Excel sheet contains a Read-Me file explaining the
 abbreviations and type of data collected. The Nature Plants manauscript
 has a detailed methods section that outlines data collection and
 methodology in statistical approach.  We appreciate
 notification of data re-use. Please use the contact
 Erik.Poelman@wur.nl