Evaluation of the effect of drought stress and seed pretreatment on physiological and biochemical traits of Chenopodium quinoa seedlings

Dashab | Heshmat Omidi

---

URL :   http://research.shahed.ac.ir/WSR/WebPages/Report/PaperView.aspx?PaperID=148182
Date :  2021/02/09
Publish in :    فيزيولوژي گياهان زراعي

Link :  http://cpj.iauahvaz.ac.ir/browse.php?mag_id=46&slc_lang=fa&sid=1
Keywords :Antioxidants, Polyethylene Glycol, Flavonoids and Quinoa.

Abstract :

---

In this study, in order to investigate the effect of seed pretreatment on quantitative and qualitative characteristics of quinoa seedlings under drought stress, a factorial experiment was conducted in a completely randomized statistical design with three replications in the research greenhouse of the Faculty of Agricultural Sciences of Shahed University in 2019. In this experiment, seed pretreatment was performed at two levels of hydro-priming for 12 hours and bio-priming with bacteria (Bacillus subtillis) for 24 hours and drought stress at five levels of 0, -0.5, -1, -1.5 and -2 MPa with PEG 6000. The results showed that the effect of pretreatment on all studied traits except malondialdehyde content and membrane stability was significant. Application of growth-promoting bacteria leads to improvement of quinoa seedling indices such as fresh weight content of shoots (29 g), chlorophyll content (40.65 μg/g), carotenoids (2179.3 μg / g), activity of superoxide dismutase enzymes (16.60 mg/g protein) and catalase (3.07 mg/g protein), total phenol (52 mol/g), flavonoids (62.65 mol/g). Increased drought stress resulted in a decrease in shoot fresh weight, carotenoid content, total sugar and protein content, but increased content of chlorophyll, proline, total phenol, flavonoids and catalase activity under drought stress conditions. Also, the interaction of the effect of pretreatment on drought stress on chlorophyll a content was significant and the highest chlorophyll content (28.05 μg/g) was obtained at -2 MPa and bio-priming stress. Therefore, bio-priming with bacteria (Bacillus subtillis) is recommended to achieve the maximum fresh weight of shoots, enzymatic and non-enzymatic antioxidants of quinoa.