Title: | Robotic mechanical wounding (MecWorm) versus herbivore-induced responses: early signaling and volatile emission in Lima bean (Phaseolus lunatus L.) |
Author(s): | Bricchi I; Leitner M; Foti M; Mithofer A; Boland W; Maffei ME; |
Address: | "Plant Physiology Unit, Department of Plant Biology, Innovation Centre, University of Turin, Via Quarello 11/A, 10135 Turin, Italy" |
DOI: | 10.1007/s00425-010-1203-0 |
ISSN/ISBN: | 1432-2048 (Electronic) 0032-0935 (Linking) |
Abstract: | "Insect herbivory on plants is a complex incident consisting of at least two different aspects, mechanical damage and chemical factors. Only the combination of both is able to induce the respective plant defenses. Thus, diverse plant species emit volatile organic compounds (VOCs) in response to herbivory (HW), whereas mechanical damage inflicted as single wounding event (MD) does not induce increased VOC emissions. In contrast, a robotic worm (MecWorm, MW) allowed demonstrating that continuous mechanical damage is sufficient to induce volatile emission in Lima bean. However, the induced VOC blends remain characteristic for the respective stimulus. In order to identify putative differences in plant signaling leading to defenses, we compared time courses of early signals induced by wounding in Lima bean. Neither MD nor MW alone was able to induce plasma membrane (V (m)) depolarization, as observed after Spodoptera littoralis HW, but V (m) depolarization occurred in both treatments when used in combination with herbivore-derived oral secretions. A significant increase in cytosolic Ca(2+) concentrations was observed only after HW, whereas MD and MW did not affect this second messenger. H(2)O(2) was generated within 2-3 h after leaf damage by HW and MW, whereas MD induced only half of the H(2)O(2) levels compared to the other treatments. Both HW and MW induced a marked accumulation of NO, but with distinct temporal patterns. NO production after MD followed the same trend but reached significantly lower values. The results indicate that chemical signals from the herbivores are responsible for the induction of the earliest signaling events. These changes appear to be characteristic for the reaction to herbivory" |
Keywords: | Animals Calcium/metabolism Cytosol/metabolism Feeding Behavior Hydrogen Peroxide/metabolism Membrane Potentials Nitric Oxide/metabolism Phaseolus/*metabolism *Robotics Spodoptera/*physiology Volatilization; |
Notes: | "MedlineBricchi, Irene Leitner, Margit Foti, Maria Mithofer, Axel Boland, Wilhelm Maffei, Massimo E eng Germany 2010/06/22 Planta. 2010 Aug; 232(3):719-29. doi: 10.1007/s00425-010-1203-0. Epub 2010 Jun 19" |