Transcriptome analysis of intraspecific competition in Arabidopsis thaliana reveals organ-specific signatures related to nutrient acquisition and general stress response pathways
1 Department of Plant Molecular Biology, University of Lausanne, Lausanne, 1015, Switzerland
2 Present address: Max Planck Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, Köln, 50829, Germany
3 Department of Ecology and Evolution, University of Lausanne, Lausanne, 1015, Switzerland
BMC Plant Biology 2012, 12:227 doi:10.1186/1471-2229-12-227Published: 29 November 2012
Plants are sessile and therefore have to perceive and adjust to changes in their environment. The presence of neighbours leads to a competitive situation where resources and space will be limited. Complex adaptive responses to such situation are poorly understood at the molecular level.
Using microarrays, we analysed whole-genome expression changes in Arabidopsis thaliana plants subjected to intraspecific competition. The leaf and root transcriptome was strongly altered by competition. Differentially expressed genes were enriched in genes involved in nutrient deficiency (mainly N, P, K), perception of light quality, and responses to abiotic and biotic stresses. Interestingly, performance of the generalist insect Spodoptera littoralis on densely grown plants was significantly reduced, suggesting that plants under competition display enhanced resistance to herbivory.
This study provides a comprehensive list of genes whose expression is affected by intraspecific competition in Arabidopsis. The outcome is a unique response that involves genes related to light, nutrient deficiency, abiotic stress, and defence responses.