Under the treatment of 0 5—2 0 μA direct electric currents, the number of cell clusters derived from wheat (Triticum aestivum L.) protoplasts was dramatically increased.The effect was related to the time length of the treatments, and appeared only when the time length was more than the threshold. The threshold time decreased with increase of electric current intensity.The effect was not related to the starting time of the treatments in culture of the protoplasts.