Systemic acquired resistance is an important mechanism of resistance to diseases in plants. In this research, the action of acibenzolar-S-methyl (ASM), a benzothiadiazole inductor of resistance in plants, was evaluated regarding tuber sprout and induction of resistance in potato (Solanum tuberosum) plants. At 60, 120, 150, 200, and 250 mg a.i. l -1, ASM did not inhibit bud number. However, in higher concentrations it decreased bud length. In the greenhouse, ASM was applied (60 and 120 mg a.i. l -1) to tubers and plants of the cultivars Asterix, Baronesa, and Monalisa. In the Asterix cultivar, ASM induced resistance to blackleg. In Baronesa cultivar plants, resistance to blackleg was achieved with tuber treatment with ASM. In Monalisa cultivar, the ASM did not induce resistance to the disease. In conclusion, the role of ASM in inducing resistance to blackleg seems to be cultivar specific.
