Interior spruce_Bark_Leptographium abietinum_inoculation

Using 21K spruce microarray (that contains 21.8 thousand unique transcripts) we performed analysis of the transcriptome response of interior spruce (Picea glauca x engelmannii) inoculated with the spruce beetle (Dendroctonus rufipennis) vectored blue stain fungal pathogen Leptographium abietinum or treated with wounding. This microarray analysis revealed large transcriptome reorganization with close to 2000 transcripts (10% of the studied transcriptome) differentially expressed within two weeks of treatment, with the wounding response affecting close to 5% of the interior spruce transcriptome. RNA was isolated from the bark of interior spruce inoculated with Leptographium abietinum, treated with wounding, or untreated control for three time points (6h, 2days and 2 weeks). Three independent biological replicates were included for each treatment and each time point. Three hybridizations were performed for each comparison of different treatments (fungal, wounding, control) within each time point (6 hours, 2 days, 2 weeks) and one hybridization was performed for the comparison of the same treatments between time points (total 36 hybridizations/slides).