RNA-seq of different poplar species reveals conserved up-regulation of gene expression in response to insect herbivory

Herbivorous insects can have a profound impact on plant growth performance. In some years, canopy damage in poplar plantations exceeds 50% of the total leaf surface, thereby possibly compromising carbon fixation and biomass yield. To assess the transcriptional response of elite poplar clones to insect feeding and to test whether this response varies between different genotypes, we performed an RNA-sequencing experiment. We deeply sequenced the transcriptomes of eight elite clones belonging to three poplar species (Populus trichocarpa, P. nigra and P. maximowiczii), under Phratora vitellinae feeding and control conditions. This allowed us to precisely quantify transcript levels of about 24,000 expressed genes.