title: Feeding damage to plants increases with plant size across 21 Brassicaceae species.
abstract: Plant size is a major predictor of ecological functioning. We tested the hypothesis that feeding damage to plants increases with plant size, as the conspicuousness of large plants makes resource finding and colonisation easier. Further, large plants can be attractive to herbivores, as they offer greater amounts and ranges of resources and niches, but direct evidence from experiments testing size effects on feeding damage and consequently on plant fitness is so far missing. We established a common garden experiment with a plant size gradient (10-130 cm height) using 21 annual Brassicaceae species, and quantified plant size, biomass and number of all aboveground components (flowers, fruits, leaves, stems) and their proportional feeding damage. Plant reproductive fitness was measured using seed number, 1000 seed weight and total seed weight. Feeding damage to the different plant components increased with plant size or component biomass, with mean damage levels being approximately 30 % for flowers, 5 % for fruits and 1 % for leaves and stems. Feeding damage affected plant reproductive fitness depending on feeding damage type, with flower damage having the strongest effect, shown by greatly reduced seed number, 1000 seed weight and total seed weight. Finally, we found an overall negative effect of plant size on 1000 seed weight, but not on seed number and total seed weight. In conclusion, being conspicuous and attractive to herbivores causes greater flower damage leading to higher fitness costs for large plants, which might be partly counterbalanced by benefits such as enhanced competitive/compensatory abilities or more mutualistic pollinator visits.
authors.affiliation: Agroecology, Georg-August-University, Grisebachstraße 6, 37077, Göttingen, Germany. hella.schlinkert@agr.uni-goettingen.de.
authors.forename: Hella
authors.initials: H
authors.lastname: Schlinkert
authors.affiliation: Agroecology, Georg-August-University, Grisebachstraße 6, 37077, Göttingen, Germany.
authors.forename: Catrin
authors.initials: C
authors.lastname: Westphal
authors.affiliation: Agroecology, Georg-August-University, Grisebachstraße 6, 37077, Göttingen, Germany.|Centre for Environmental and Climate Research, Sölvegatan 37, 223 62, Lund, Sweden.
authors.forename: Yann
authors.initials: Y
authors.lastname: Clough
authors.affiliation: Agroecology, Georg-August-University, Grisebachstraße 6, 37077, Göttingen, Germany.|Department Phytomedicine, Institute of Horticultural Production Systems, Leibniz University Hannover, Herrenhäuserstr. 2, 30419, Hannover, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Ludwig
authors.affiliation: Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands.
authors.forename: Patrick
authors.initials: P
authors.lastname: Kabouw
authors.affiliation: Agroecology, Georg-August-University, Grisebachstraße 6, 37077, Göttingen, Germany.
authors.forename: Teja
authors.initials: T
authors.lastname: Tscharntke
mesh_terms: D018533:Biomass; D019607:Brassicaceae / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology*; D035264:Flowers / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology; D060434:Herbivory; D018515:Plant Leaves / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology; D054817:Pollination; D012639:Seeds / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology; D013559:Symbiosis
keywords: Antagonists; Herbivory; Plant fitness; Pollen beetles; Trophic interactions