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Full list of author information is available at the end of the articleBackground Potato is today the third largest food crop in the world. One of the largest threats to potato production is late blight disease, caused by Phytophthora infestans, which is currently controlled by frequent use of fungicides. Ex-tensive efforts to find more efficient weapons against late blight are ongoing worldwide. One alternative could be integration of induced resistance (IR) in current manage-ment strategies. IR, i.e. exposing plants to abiotic or bi-otic stress leading to improved resistance to subsequent pathogen attack both locally and systemically [1], is thought to function by activating or enhancing defence signalling [2]. This signalling is suggested to depend either on salicylic acid (SA) or jasmonic acid/ethylene (JA/ET) for the two classical forms of IR: systemic acquired resistance (SAR) and induced systemic resistance (ISR), respectively [3]. Resistance can be induced by treatmen