Two field experiments were carried out to study the effect of some stimulant substances, i.e., benzyladenine at 25, 50 ppm and blue green algae “Spirulina platensis” extract at 0.3, 0.6 % as well as yeast extract at 5, 10 % as individual treatments on growth and yield traits in addition to anatomical and chemical constituents of Solanum tuberosum L. The results showed a significant improving in the most of vegetative growth and yield characteristic with applied treatments compared with the control. Consequently, treating potato plants with spirulina algae extract at 0.6 or 0.3 % or yeast extract at 10 %, respectively three times lead to obtain vigorous vegetative growth of Solanum tuberosum L. plant with increasing in both of tuber yield and its quality characteristics. |