Large scale analysis of leaf gene expression upon treatment of apple seedlings with acibenzolar-S-methyl or water

Investigation of whole genome gene expression level changes in the youngest expanded leaves of open-pollinated Golden Delicious seedlings either sprayed with reverse osmosis water or acibenzolar-S-methyl (ASM). Treatment was performed by spraying sprayed to runoff (with a pressurized hand sprayer) with the commercial product Bion 50 WG (Syngenta, Basel, Switzerland; 50% of ASM) prepared in reverse osmosis water at a final concentration of 0.4 g/L. The youngest developped leaf of each seedling was sampled 3 days after the treatment. A total of 8 samples were associatied as pairs to perform 4 competitive hybridisations, including dye switch. Biological replicates are from 4 independantly grown apple seedling series. These comparisons allowed to determine the impact of ASM on apple gene expression. This is a dual channel array processed as a single-channel analysis.