| Interactive Effects of Arsenic and Heat Stress on Plant Arsenic Uptake and Physiological Attributes of Quinoa |
| Paper ID : 1179-IGA |
| Authors |
|
GHULAM ABBAS * COMSATS University Islamabad, Pakistan |
| Abstract |
| Soil contamination with heavy metals including arsenic (As) and heat stress are resulting in severe decline in crop production around the world. The aims of the current experiment were to evaluate physiological and biochemical changes induced by the combination of As and heat stress in quinoa. Plants were gown in pots under different concentrations of arsenite (0, 10, 20 and 30 mg kg-1 soil) under ambient temperature (30/12 ℃ day/night) or 5 ℃ higher than ambient temperature. Plant growth, leaf relative water contents, membrane stability index, stomatal conductance, chlorophyll contents, and grain yield were significantly decreased under As stress. The combination of heat stress with As further decreased these attributes in quinoa plants. Heat stress also increased As accumulation in plants and the plants treated with As levels higher than 20 mg As kg-1 soil, with or without heat stress, could not reach maturity. The uptake of As under all the treatments was in the order of root > shoot > grains. Oxidative stress resulting from As and heat stress increased the TBARS and H2O2 contents and declined the stability of cell membranes. The over expression of antioxidant enzymes (CAT, POD, SOD) partly neutralized the oxidative stress in quinoa caused by As and heat stress. It can be concluded that quinoa is not suitable for cultivation in areas having high ambient temperatures and soils contaminated with As levels greater than 20 mg As kg-1 soil. |
| Keywords |
| Soil arsenic contamination, High temperature, Quinoa, Oxidative stress |
| Status: Accepted |
