Title: | The impact of Spodoptera exigua herbivory on Meloidogyne incognita-induced root responses depends on the nematodes' life cycle stages |
Author(s): | Mbaluto CM; Ahmad EM; Fu M; Martinez-Medina A; van Dam NM; |
Address: | "Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany. Institute of Biodiversity, Friedrich-Schiller-Universitat-Jena, Jena, Germany. Department of Genetics, Faculty of Agriculture, Cairo University, Giza, Egypt. Faculty of Land and Food Systems, University of British Columbia, BC, Canada. Plant-Microorganism Interaction Unit, Institute of Natural Resources and Agrobiology of Salamanca (IRNASA-CSIC), Salamanca, Spain" |
ISSN/ISBN: | 2041-2851 (Print) 2041-2851 (Electronic) |
Abstract: | "Induced responses to above-ground and below-ground herbivores may interact via systemic signalling in plants. We investigated whether the impact of above-ground herbivory on root-knot nematode-induced responses depends on the nematode's life cycle stages. Tomato plants were infected with the nematode (Meloidogyne incognita) for 5, 15 or 30 days before receiving Spodoptera exigua caterpillars above-ground. We collected root materials after 24 h of caterpillar feeding. We investigated phytohormones and alpha-tomatine levels, and the expression of defence and glycoalkaloid metabolism (GAME) marker genes in tomato roots. Nematode infection alone increased the endogenous root levels of jasmonic acid (JA), salicylic acid (SA), abscisic acid (ABA), alpha-tomatine and the expression of the GLYCOALKALOID METABOLISM 1 (GAME1) gene mostly at 30 days post-nematode inoculation. Caterpillar feeding alone upregulated Lipoxygenase D and downregulated Basic-beta-1-glucanase and GAME1 expression in roots. On nematode-infected plants, caterpillar feeding decreased JA levels, but it increased the expression of Leucine aminopeptidase A. The induction patterns of ABA and SA suggest that caterpillars cause cross-talk between the JA-signalling pathway and the SA and ABA pathways. Our results show that caterpillar feeding attenuated the induction of the JA pathway triggered by nematodes, mostly in the nematodes' reproduction stage. These results generate a better understanding of the molecular and chemical mechanisms underlying frequent nematode-plant-caterpillar interactions in natural and agricultural ecosystems" |
Keywords: | Above-ground-below-ground interaction Solanum lycopersicum Spodoptera exigua phytohormones root-knot nematodes steroidal glycoalkaloids systemic-induced responses; |
Notes: | "PubMed-not-MEDLINEMbaluto, Crispus M Ahmad, Esraa M Fu, Melody Martinez-Medina, Ainhoa van Dam, Nicole M eng England 2020/07/16 AoB Plants. 2020 Jun 24; 12(4):plaa029. doi: 10.1093/aobpla/plaa029. eCollection 2020 Aug" |