Cyanobacterial extracts have been used as biofertilizers to improve the growth of plants. Quinoa is a drought tolerant plant that has a special need for nitrogen fertilizers. Therefore, due to nitrogen fixation in cyanobacteria Nostoc sp. 5 and 1gl-1 extracts were used to study the growth parameters of quinoa. Concentrations of 0, 20, 40 and 80% of these extracts were prepared and 5 ml of them was added to the petri dishes. The petridishes containing 15 seeds were placed on the light cultivation shelf for 7 days at 25°C. Then, the growth parameters including of germination percentage, seedling weight, shoot length, root length, root-to-shoot ratio and seedling vigor were examined. The results showed that different dilutions of 5 gl-l extract did not show a significant increase in growth parameters and often a decrease was observed with increasing of concentrations. Different dilutions of 1 gl-1 extracts increased the shoot length which the concentrations of 40 and 80% showed a significant increase compared to the control. Concentration of 20% showed a significant increase in root length and seedling vigor compared to the control and with increasing of concentrations, these parameters decreased. The ratio of root to shoot decreased with increasing of concentrations and concentrations of 40 and 80% showed a significant decrease compared to the control. Germination percentage and seedling weight at different concentrations of both extracts did not show significant differences. It seems that different dilutions of 1 gl-1 extract of Nostoc sp. are more effective in improving growth parameters.
