We investigated the effects of postharvest application of carbon disulphide (CS2) in various concentrations (0, 15, 25, 35, 45 and 55 ml m-3) and with different exposure duration (24, 48, 72 and 96 h) on breaking of dormancy and sprouting of potato (Solanum tuberosum L., cv. Marfona) minitubers of two ages (freshly harvested and one week after harvest) and two weight classes (1.5 and 12 g). In comparison with the control minitubers, CS2 treated minitubers showed significantly shorter dormancy and better sprouting. More rotting and weaker responses were observed in freshly harvested treated minitubers compared with minitubers treated one week after harvest. The number of sprouts per minituber and their length were significantly enhanced by treating minitubers with CS2 compared with the untreated control minitubers, but there were strong interactions with minituber weight. Results showed that duration of CS2 treatment was more important than concentration and longer duration of CS2 treatment exhibited a stronger action on breaking dormancy and sprouting of potato minitubers than shorter treatments. But, when longer duration was accompanied with higher concentration, treatment with CS2 led to formation of needle sprouts, which are undesirable as they do not produce vigorous stem