Seed potato production in a second crop is one of the method to reduce the pressure of viruses and ecological degeneration, and keep longer the seed in good physiological condition and free of virus diseases. Dormancy period of the new harvest tubers is one of major impediment. Not all the variety are good for second crop. Experiment was done with 3 varieties: Minerva, Riviera- extra early and Agata – from early group of maturity and 4 large known chemicals. For rapid and qualitative dormancy breaking the best solution is to use the combination of gibberellic acid, thiourea, succinic acid, potassium thiocyanate. Effi ciency of dormancy broken depends of biological particularities of variety and concentration of chemicals in solution. For reduce the number of routed tubers aſt er the cutting, and the attack of the pest in the soil and aſt er emergence of the plants in solution was introduced 4 kg of TMTD fungicide and 11l of Prestige 290 FS.