KNAW Repository

Interactions between above- and belowground insect herbivores as mediated by the plant defence system

Bezemer, T.M. and Wagenaar, R. and Van Dam, N.M. and Wäckers, F.L. (2003) Interactions between above- and belowground insect herbivores as mediated by the plant defence system. Oikos, 101, 555-562. ISSN 0030-1299.

[img]PDF - Published Version
Restricted to KNAW only

104Kb

Official URL: http://dx.doi.org/10.1034/j.1600-0706.2003.12424.x

Abstract

Plants are frequently attacked by both above- and belowground arthropod herbivores. Nevertheless, studies rarely consider root and shoot herbivory in conjunction. Here we provide evidence that the root-feeding insect Agriotes lineatus reduces the performance of the foliage feeding insect Spodoptera exigua on cotton plants. In a bioassay, S. exigua larvae were allowed to feed on either undamaged plants, or on plants that had previously been exposed to root herbivory, foliar herbivory, or a combination of both. Previous root herbivory reduced the relative growth rates as well as the food consumption of S. exigua by more than 50% in comparison to larvae feeding on the undamaged controls. We found no effects in the opposite direction, as aboveground herbivory by S. exigua did not affect the relative growth rates of root-feeding A. lineatus. Remarkably, neither did the treatment with foliar herbivory affect the food consumption and relative growth rate of S. exigua in the bioassay. However, this treatment did result in a significant change in the distribution of S. exigua feeding. Plants that had been pre-exposed to foliar herbivory suffered significantly less damage on their young terminal leaves. While plant growth and foliar nitrogen levels were not affected by any of the treatments, we did find significant differences between treatments with respect to the level and distribution of plant defensive chemicals (terpenoids). Exposure to root herbivores resulted in an increase in terpenoid levels in both roots as well as in mature and immature foliage. Foliar damage, on the other hand, resulted in high terpenoid levels in young, terminal leaves only. Our results show that root-feeding herbivores may change the level and distribution of plant defenses aboveground. Our data suggest that the reported interactions between below- and aboveground insect herbivores are mediated by induced changes in plant secondary chemistry

Item Type:Article
Institutes:Nederlands Instituut voor Ecologie (NIOO)
ID Code:11288
Deposited On:24 Nov 2011 01:00
Last Modified:31 Mar 2014 10:14

Repository Staff Only: item control page