Fatemeh Mirzaei; Mohammad Rafieiolhossaini; Nafiseh Rangzan; Mahdi Amirusefi
Abstract
Objective: Quinoa, with its high nutritional value, is highly resistant to a wide range of non-biological stresses. Despite the limited resources and the increasing demand for food products in lands with low or limited fertility, it can be cultivated well and produces a good product.
Methods: This experiment ...
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Objective: Quinoa, with its high nutritional value, is highly resistant to a wide range of non-biological stresses. Despite the limited resources and the increasing demand for food products in lands with low or limited fertility, it can be cultivated well and produces a good product.
Methods: This experiment was conducted with the aim of investigating the simultaneous effect of drought stress and heavy metals on the quinoa plant, in a factorial format in a completely randomized design with 3 replications. The first component involved two levels of soil (contaminated and uncontaminated), and the second factor, three levels of drought stress (100% of field capacity 60% of field capacity, and 30% of field capacity).
Results: Interaction effect of soil type and drought stress was significant on all traits except the fresh weight of shoot and plant height. The lowest amount of fresh and dry weight of roots, dry weight of shoot and weight of thousand seeds was observed in contaminated soil with severe drought stress. Nevertheless, the weight of 1000 quinoa seeds under the influence of moderate drought stress was not significantly different from the condition without drought stress. Examining the simple effects showed that soil contamination with heavy metals caused a decrease of 13.7% in fresh weight of shoot and 30.5% decrease in dry weight of shoot compared to plants grown in uncontaminated soil.
Conclusion: In general, it can be stated that the increase in drought stress has significantly reduced root fresh weight and 1000 seed weight in quinoa, but the percentage and ratio of this reduction in soil contaminated with heavy metals was much higher than that of non-contaminated soil. According to the results of this research, the cultivation of quinoa can be investigated as a promising plant in soils with similar limitations.
Mohsen Seilsepour
Abstract
This study is conducted to evaluate the concentration of nitrate and heavy metals in soil and edible organs of lettuce in Varamin plain farms for one year during 2017-2018. For this porouse, 30 lettuce fields in Varamin plain are selected and in the lettuce harvest season, soil and crop sampling are ...
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This study is conducted to evaluate the concentration of nitrate and heavy metals in soil and edible organs of lettuce in Varamin plain farms for one year during 2017-2018. For this porouse, 30 lettuce fields in Varamin plain are selected and in the lettuce harvest season, soil and crop sampling are performed and the average concentrations of nitrate and heavy metals in the soil and lettuce were compared statistically with the standard limits by one paired t-test. The average concentrations of nitrate, lead and cadmium in lettuce are 2756, 1.46, and 0.11 mg/kg in fresh weight, respectively, which are 1.8, 7.3, and 1.1 times greater than the standard limit, declared by the National Standards Organization of Iran, respectively. The mean concentrations of nitrate and total concentrations of lead, cadmium, and nickel in the soil of lettuce fields are 27, 42, 0.64, and 42.5 mg/kg, respectively, while the concentrations of nitrate and lead have been 35% and 180% higher than the allowable limits, respectively. Risk assessments for heavy metals and non-cancerous diseases are performed, using formulas provided by the US Environmental Protection Agency (USEPA, 2006). In this regard, the risk index for non-cancerous diseases (HQ) is used. The risk factor for non-cancerous diseases for all contaminants is less than one, indicating that there is no risk for consumption. Accordingly, consuming 40 grams of lettuce per day does not pose a problem for an adult consumer. The bioaccumulation index for all the studied metals has been less than one. According to this study, the highest bioaccumulation factor belongs to the heavy metal cadmium, which indicates the tendency of lettuce to absorb and accumulate cadmium compared to other heavy metals. In order to reduce the concentration of nitrate and lead in the soil and prevent contamination of lettuce soils, it is recommended to avoid excessive use of fertilizers containing nitrogen and phosphorus and fertilizer application should be based on soil test. According to the results of this study, there is no serious possibility of exposure to non-cancerous diseases caused by nitrate and heavy metals from eating lettuce, but monitoring the concentration of nitrate and heavy metals in soil and lettuce at different intervals is necessary.