Abstract :
Quinoa (Chenopodium quinoa Willd.) is a grain-like crop with a high-grown potential in Iran. It has high nutritional value and therefore, is compared to milk by the FAO. This study was conducted to evaluate quinoa seedlings physiological and biochemical properties under the effects of priming and drought stress treatments. The experiment was factorial based on a completely randomized design in a greenhouse at the Agriculture Faculty of Shahed University, Tehran, Iran. Experimental factors included priming at two levels (hydro-priming and bio-priming) and drought stress at five levels (control (0), -0.5, -1, -1.5, and -2 MPa with polyethylene glycol). Analysis of variance showed that the effects of priming and drought stress were significant on most of the studied traits. The results showed a significant decrease in quinoa seedling indices (such as shoot and root dry weight) under high levels of drought stress. However, the application of biopriming (growth-promoting bacteria) improved physiological indices, such as proline content and antioxidant enzyme activity. Interactions of priming and drought stress had significant effects on fructose, glucose, and proline content. The highest seedling proline content was related to -2.0 MPa in bio-priming (8.67 μmol/g FW) while the lowest proline content was recorded under non-stress conditions in hydro- and bio-priming (2.95 and 3.11 μmol/g FW). This study showed that the highest mean dry weight of shoots, protein content, and enzymatic and non-enzymatic antioxidants were observed at the bio-priming level. The priming treatments (hydro and bio) led to improvements in characteristics such as root dry weight, proline content, superoxide dismutase activity, and anthocyanin content. These led to the mitigation of the adverse effects of drought stress.
Keywords :
antioxidant activity , growth , promoting bacteria , Polyethylene glycol , Proline content , shoot and root dry weight
