Boron Fertilization Enhances the Induced Defense of Silver Birch |
| |
Authors: | Teija Ruuhola Tuomo Leppänen Riitta Julkunen-Tiitto Markus J Rantala Tarja Lehto |
| |
Affiliation: | (1) School of Forest Sciences, University of Eastern Finland (UEF), P.O. Box 111, FI-80101 Joensuu, Finland;(2) Department of Biology, University of Eastern Finland (UEF), P.O. Box 111, FI-80101 Joensuu, Finland;(3) Section of Ecology, Department of Biology, University of Turku, FI-20014 Turku, Finland |
| |
Abstract: | Boron (B) deficiency is a common micronutrient deficiency that has been reported to affect the phenolic metabolism of plants.
Thus, it may play a role in defense against herbivorous animals. However, the role of B in a plant’s resistance to herbivores
has not received any particular attention from researchers. In this study, we tested the effects of B nutrition 1) on the
biochemical and mechanical defenses of birches and the growth of seedlings, and 2) the resistance of seedlings to larvae of
the autumnal moth, Epirrita autumnata. Boron fertilization improved the resistance of birch, which was shown as reduced pupal weight of the herbivore. However,
B fertilized trees suffered from heavier defoliation than unfertilized ones due to compensation feeding of larvae. The growth
of the seedlings was diminished, and several biochemical changes occurred in leaves of herbivore seedlings, and B also played
a role in these changes. Polyphenoloxidases (PPOs) and peroxidases (PODs) and their substrates, chlorogenic acids, were induced
by herbivory in B fertilized seedlings but not in unfertilized seedlings. The lower pupal weights and increased consumption
of the herbivores were probably linked to the plants’ phenoloxidase-mediated production of reactive quinones, which decrease
the nutritive value. Herbivory upon new stems led to an increase in the number of resin glands that provide defense against
mammalian herbivores. Herbivory also had a substantially negative effect on B concentration in leaves of B fertilized seedlings.
We postulate that B nutrition of trees may play a significant role in the induced defense of birches. |
| |
Keywords: | |
本文献已被 PubMed SpringerLink 等数据库收录! |
|