Growing vegetables
K. Poorhossein; B. Abedy; M. Shour
Abstract
Introduction Urban agriculture is one of the basic characteristics of urban schematization, which helps to increase the quality of urban life via reducing the climate pollution, preserving and increasing biodiversity, as well as re-utilizing urban waste. Therefore, in recent years, urban agriculture ...
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Introduction Urban agriculture is one of the basic characteristics of urban schematization, which helps to increase the quality of urban life via reducing the climate pollution, preserving and increasing biodiversity, as well as re-utilizing urban waste. Therefore, in recent years, urban agriculture has gained significant importance due to its economic, social and cultural benefits. However, studies have indicated that urban soils can contain high concentrations of certain infrequent elements such as lead and cadmium. These heavy metals can be distinguished from other pollutants because they cannot be bio-degraded; but they accumulate in living organisms and subsequently cause diseases and various disorders even in relatively lower concentrations. Plants, like other organisms, have defense mechanisms that are activated in stressful conditions. Thus, under stress, enzymatic antioxidant systems and non-enzymatic metabolites enhance, due to the production of reactive oxygen species. Peppermint plant (Mentha piperita L) has an essential oil with medicinal properties. High levels of heavy metals cause chlorosis and necrosis, increase the accumulation of reactive oxygen species (ROS) and oxidative stress in mint plants. The present study was conducted on a regional scale in order to investigate heavy metal pollution and determine their impacts on some physiological and biochemical traits as well as the concentration of Cd and Pb in peppermint plants grown in urban green spaces.Material and methodsThis study was conducted to assess the amount of heavy metal absorption and its effect on some biochemical properties of peppermint plant (Mentha piperita L.), in Mashhad city in 2021.The experiment was carried out as a factorial in the form of randomized complete block design in three replications. The first factor (location) were Faz4 Park (with high degree of contamination) and Nasim Park (with low degree of contamination). The second factor was the times of harvest (June15, July15 and August 15). At the time of every harvest fully developed leaves were collected to evaluate physiological and biochemical traits.Results and discussionThe results of analysis of variance indicated that the effect of location was significant on all traits except for the yield of essential oil. Also, the effect of harvest time was significant on all traits except for peroxidase activity and the yield of essential oil. However, the interaction of location and harvest was significant only on phenol, flavonoid, proline, cadmium and lead concentration. The results indicated that the ascorbate peroxidase, catalase and peroxidase activities were higher in Faz 4 Park. Moreover, the highest activities of ascorbate peroxidase, catalase and peroxidase were recorded in Faz 4 + first harvest. Heavy metals cause the production of reactive free radicals and also increase the activity of antioxidant enzymes. However, the chlorophyll a, b, carotenoid and total chlorophyll contents were higher in Nasim. Thus, the highest contents of Chla, Chlb, Chltotal and carotenoid were observed in Nasim + first harvest. The higher amount of chlorophyll and carotenoids in the first harvest is due to the optimal growth conditions such as day length and sunlight and ambient temperature. In addition total phenol, flavonoid, proline, Cd and Pb elements indicated a reducing trend in Faz 4 compared to Nasim Park in different harvest times, but the amount of these traits were higher in the first harvest than in the subsequent harvests. Increased amount of total phenol in the first harvest can be related to the high air temperature at the first harvest which caused stressful conditions in this stage. Proline production also improves under heavy metal stress in order to protect the plant against toxicity. Nevertheless, the percentage of essential oil showed an increasing trend via enhancing the absorption of Pb and Cd in Faz 4 compared to Nasim Park. The higher percentage of essential oil in Faz 4 can be due to the lower growth of leaves due to the presence of more heavy elements in this area. In general, despite the fact that only the concentration of Pb was higher than the world standard level in both parks, the contamination with Cd and Pb (especially Pb) was more in Faz 4 than in Nasim Park, which was a factor in diminishing the growth traits of peppermint plants. In a case of harvest times, the first harvest recorded better growth characteristics and higher absorption of heavy metals due to the higher strength of the plant, while in the third harvest, due to spending more energy for regrowth, it had lower growth characteristics and weaker absorption of Pb and Cd metals. It was cadmium.
Medicinal Plants
Saeid Shiukhy Soqanloo; Mohammad Ali Gholami; Yousef Ghasemi
Abstract
IntroductionConfronting the crisis of water scarcity and the looming challenge of dwindling water resources is undeniably a grave concern. Consequently, the focus of agricultural science researchers has shifted towards the utilization of wastewater. One of the notable advantages of incorporating wastewater ...
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IntroductionConfronting the crisis of water scarcity and the looming challenge of dwindling water resources is undeniably a grave concern. Consequently, the focus of agricultural science researchers has shifted towards the utilization of wastewater. One of the notable advantages of incorporating wastewater in agriculture is the potential to curtail the expenses associated with procuring irrigation water and employing chemical fertilizers. Materials and MethodsSari has a longitude and latitude of 53°01′ E and 36°33′ N, respectively, and its weather conditions are humid according to De-marten's climate classification. Its elevation is 21 above sea level and average annual temperature and precipitation, are17.9 ºC and 650 mm, respectively). In order to evaluate the effect of water stress and urban wastewater on the concentration of heavy metals, yield and some characteristics of basil, an experiment in a factorial format based on a completely randomized design with experimental treatments including; The first factor is the source of irrigation (I): [treated wastewater (TWW) and well water (WW)], and the second factor is water stress (S): [the lowest stress (S1, S2), medium stress (S3, S4) and severe stress (S5, S6)] were performed in three replications at the research farm of Sari University of Agricultural Sciences and Natural Resources (SANRU), Iran. Finally, the obtained data were analyzed using ANOVA of SAS9.2, and the SNK post hoc test was employed to compare treatment means. Results and DiscussionBased on the findings, Irrigation with wastewater increased plant height, stem diameter, fresh and dry weight compared to irrigation with well water. So that the highest plant height, stem diameter, wet and dry weight were related to irrigation with wastewater with 44.3 cm, 3.1 mm, 8.5 and 3.3 g, respectively. Also, the effect of using treated wastewater on chlorophyll a, chlorophyll b, total chlorophyll and carotenoids was significant (P ≤ 0.01). while it did not have significant effect on flavonoid, phenol and antioxidant activity. In the lowest stress, especially the S1 level, the amount of chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, flavonoid, phenol and antioxidant activity compared to the S6 level decreased by 63.3, 32.8, 40.7, 45.8, 46.3, 55.5, and 9.8%, respectively. while the highest amount of plant height, fresh weight, dry weight and stem diameter at the S1 level was observed with 48.6 cm, 11.5 g, 3.51 g and 3.4 mm, respectively. The result shown that the Pb and Cd concentration in basil under irrigation with wastewater was 3.4 and 2.5 mg.kg-1, respectively, which increased by 13 and 9% compared to well water. Water stress affected the Pb and Cd concentration, but the Cr and Ni concentration did not change significantly. The highest Pb and Cd concentration was related to high stress level S5 and medium stress level S4 and the lowest level was observed in the lowest stress levels (S1 and S2). Also, the results showed that the Pb and Cd concentration was affected by the interaction effect of irrigation source and water stress. Thus, the highest Pb concentration was observed in irrigation with wastewater and water stress levels S4 and S5 with 3.41 and 3.40 mg.kg-1, respectively, and the lowest was related to irrigation with well water and water stress level S1 with 2.2 mg.kg-1. The highest Cd concentration was related to irrigation with wastewater and stress levels S4 and S5 with 2.6 and 2.5 mg/kg, respectively, and the lowest amount were observed in well water irrigation and stress levels S1 and S2, with 1.51 and 1.50 mg.kg-1, respectively. while the Cr and Ni concentrations did not significant. ConclusionBased on the findings of this research, irrigation with treated wastewater and application of water stress had significant effect on the morphological and phytochemical characteristics of basil. while the use of treated wastewater was ineffective on the biochemical characteristics of basil and only water stress conditions affected their levels. The Pb and Cd concentration in basil increased under the influence of irrigation with wastewater and water stress levels. But this increase was lower than the standards authorized reported by the researchers and did not cause much concern. the results shown that the water stress levels S4 and S5 can be considered appropriate in water efficiency and recommend the use of treated wastewater in basil irrigation considering the authorized standards.
M. Haghighi; mohsen kafi
Abstract
Information of heavy metal toxicity about physiological aspect of lettuce is limited. Therefore an experiment was conducted in CRD designed with 7 replications on lettuce (Lactuca sativa L.). Treatments were cadmium in 3 concentration (0, 2 and 4 mg/L) added to Hoagland solution. Results were shown that ...
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Information of heavy metal toxicity about physiological aspect of lettuce is limited. Therefore an experiment was conducted in CRD designed with 7 replications on lettuce (Lactuca sativa L.). Treatments were cadmium in 3 concentration (0, 2 and 4 mg/L) added to Hoagland solution. Results were shown that increasing in cadmium of nutrient solution caused increasing in SOD, POD antioxidant and proline contents of leaf tissues, in addition, cadmium decreased the amount of fresh weight and organic acid. Applying 2 and 4 mg/L cadmium in nutrient solution produced POD, SOD and Proline around 8 and 53%, 55 and 106%, 39 and 119% in 2 and 4 mg/L cadmium, respectively. Whereas in the same concentrations of cadmium protein decreased 25 and 5 %, respectively. Under cadmium stress, toxic effects decline photosynthesis more than chlorophyll content.
