جستجوی مقالات مرتبط با کلیدواژه "تنش کادمیوم" در نشریات گروه "زیست شناسی"

To investigate the effect of salicylic acid on the indicators of seed germination and growth of quinoa seedlings under cadmium stress, a factorial experiment was conducted in the form of a completely randomized basic design in four replications at Mohaghegh Ardabili University. The treatments included cadmium stress at five levels (0, 50, 100, 150, and 200 mg/l), and salicylic acid at five levels (0, 1, 1.5, 2, and 2.5 mM). The results showed that with the increase in stress intensity, the average percentage and speed of germination, dry weight, and length of quinoa seedlings decreased. In non-stressed conditions, the percentage and speed of germination and the dry weight of the seedlings obtained from the seeds pretreated with salicylic acid were significantly higher than the control seeds. Also, seed pretreatment with salicylic acid significantly increased the characteristics of germination percentage, germination rate, average germination percentage, seedling length, dry weight, activity of catalase, peroxidase, and polyphenol oxidase enzymes, but decreased the average germination time, time to 90% germination. Application of 2.5 mM salicylic acid as a pre-treatment in non-stress and cadmium stress conditions increased seedling length by 46.48 and 73.83%. By using 2.5 mM concentration of salicylic acid, the activity of catalase, peroxidase, and polyphenol oxidase enzymes increased by 45.30 to 93.89, 22.51 to 51.6, and 25.4 to 45.17%, respectively. In total, seed pretreatment with 2.5 mM salicylic acid, at different levels of cadmium stress, increased seed and seedling vigor and activity. Antioxidant enzymes had the most positive effect on the germination and growth of quinoa seedlings.

Cadmium is one of the heavy metals that causes oxidative stress in plants. In this regard, the use of plant growth regulators such as salicylic acid is suggested as a suitable compound to alleviate the toxic effects of cadmium. This study was conducted to investigate the interaction between cadmium chloride and salicylic acid on growth characteristics, antioxidant enzymes activity, carbohydrate and proline content of lemon balm. This research was carried out in a factorial experiment in a completely randomized design with three replications in a plant physiology research laboratory located at the University of Zabol in 1396. Expriments factors include four different cadmium levels (0, 1, 0.5, 1 μM) and three levels of salicylic acid (0, 0.5, 1 mM). The results showed that different growth characteristics, including root and stem weight, root and shoot length, were decreased by cadmium stress. The addition of SA improved the growth characteristics. Carbohydrate and protein content were reduced by cadmium stress and SA reduced the decline. Antioxidant enzymes activity (catalase, ascorbate peroxidase, Guaiacol peroxidase) as well as malondialdehyde content increased under cadmium stress conditions. While SA decreased malondialdehyde content and antioxidant enzymes activity. These findings suggest that the use of salicylic acid somewhat eliminates some of the toxic effects of cadmium and improved the tolerance of lemon balm under cadmium stress.

Cadmium (Cd) is a heavy metal that causes oxidative stress in plants. In this study toxicity effect of Cd on Silybum marianum was investigated. Four treatments of CdCl2 (0, 300, 600, 400 and 900 μM) were evaluated in five replications using complete random design. Results of tolerance stress index severity of Cd stress on plants under various levels of treatments. Shoot dry weight, leaf area, chlorophyll a content, and total chlorophyll content were significantly reduced in 900 μM of Cd. Chlorophyll b decreased in all levels of Cd stress in comparison with control. Meanwhile, Carotenoid content did not show significant change in different concentrations of cadmium. Malon De Aldehyde content, Antocyanin content, total Phenol and Flavonoid significantly increased under 900 μM cadmium concentration. Total protein content was significantly decreased in 900 μM Cd concentration while, Phenylalanine ammonia lyase, Glutathione reductase and Ascorbate peroxidases activity enzyme were significantly increased in this level. Results confirmed that this medical plant have different physiological and biochemical mechanisms to reduce toxicity damage of cadmium. Evaluation of cadmium ion concentration in leaves and root showed that most cadmium was concentrated in leaves while; small amount of Cd was in the roots. These results showed that silybum marianum could be an appropriate plant for phytoremediation purposes.

Cadmium (Cd) is an environmentally polluting metal that has a negative effect on plant growth and yield. In this study, to understand the role of salicylic acid (SA) in alleviating cadmium toxicity in Sage (Salvia officinalis L.), the changes of biochemical and physiological indexes in Sage seedlings exposed to 0, 100, 200 or 300 ppm Cd with or without 0.1, 0.5 and 1 mM SA for 30 days was investigated. The results showed that Cd treatment reduced the growth, photosynthetic pigments, soluble sugars and activity of catalase and peroxidase enzymes, while increased proline content, phenolic compounds, MDA and H2O2. However, SA pre-treatment improved the growth and increased content of photosynthetic pigments, proline, soluble sugars and phenolic compounds at all levels of cadmium. Furthermore, SA pretreatment increased the activity of antioxidant enzymes catalase and peroxidase, and reduced MDA and H2O2, which reduced the cadmium-induced oxidative stress and, consequently, increased Sage tolerance to cadmium. According to our results, it seems SA might regulate the antioxidant defense activities, increase osmolyte and secondary metabolite compound in Cd-treated Sage, thereby improving growth and tolerance of Sage to Cd stress