Identification of defense-related genes in tobacco responding to black shank disease

In order to identify tobacco (Nicotiana megalosiphon) genes involved in broad-spectrum resistance to tobacco black shank (Phytophthora parasitica var. nicotianae), suppression subtractive hybridization (SSH) was used to generate a cDNA from transcripts that are differentially expressed during an incompatible interaction. Forty-eight differentially expressed genes were selected, sequenced and analyzed. The cDNA collection comprised a repertoire of genes associated with various processes. Real-time PCR analysis of a subset of these genes confirmed the differential expression patterns between the compatible and incompatible interaction. The experiments demonstrated for the first time that hrs203J gene and RING finger protein gene exhibited strong induction during several incompatible interactions. Also, these genes were found not to be induced in compatible interactions. The set of differentially expressed tobacco genes associated to resistance could be exploited in strategies to develop durable resistance in cultivated tobacco plants.