Transcriptional rearrangements in tomato in response to herbivory and signals of competition

ABSTRACT: In plants, an increase in resource allocation to growth (primary metabolism) associated with the presence of neighbors is likely to reduce defense-related production (secondary metabolism), making plants more vulnerable to herbivory. Even though there is increasing evidence supporting this “trade-off hypothesis”, the underlying mechanisms are still unclear. Far red (FR) radiation reflected from plant tissues serves as an early warning signal of future competition, triggering a suite of plastic morphological adjustments that improve plant’s ability to compete for light in crowded populations. Recent evidence from our lab showed that, when competition signals are present, plant defenses are severely reduced. Besides direct effects of herbivory and competition signals on target plants, second order effects occurs on neighboring plants through plant volatiles (PVs) communication. PVs play a key role in plant-plant and plant-insect interactions, changing its content and composition in response to environmental conditions. To increase our understanding of the molecular mechanisms underlying those interacting signaling webs, we performed a field study with tomato plants (cv Moneymaker), in which plants of EMITTER plots (six plants plot-1) were subjected to herbivory (nine larvae of Spodoptera eridania plant-1) and competition signals (increased FR radiation) in a factorial design. Light treatment started 28 days after sowing (DAS), and herbivory treatment and volatiles conduction started 34 DAS. Volatiles were conducted from EMITTER to RECEIVER plots (five plants plot-1) using a 5 inch, 1.4 m long tube fitted with a computer-type fan. 40 and 45 DAS, larval performance was measured on EMITTER plots as well as naturally-occurring insect colonization on RECEIVER plots. Finally (46 DAS), samples for bulk phenolic content were taken on every plot, and plant material from 4th and 5th leaves was collected for microarray analysis. There were three real biological replicates. Keywords: Reference design

ORGANISM(S): Solanum tuberosum Solanum lycopersicum

PROVIDER: GSE10486 | GEO | 2008/02/13

SECONDARY ACCESSION(S): PRJNA107935

REPOSITORIES: GEO