Soil and water contamination from heavy metals and metalloids is one of the most discussed and caused adverse effects on food safety and marketability, crop growth due to phytotoxicity, and environmental health of soil organisms. A hydroponic investigation was executed to evaluate the influence of citric acid (CA) on copper (Cu) phytoextraction potential of jute (Corchorus capsularis L.). Three-weeks-old seedlings of C. capsularis were exposed to different Cu concentrations (0, 50, and 100 μM) with or without the application of CA (2 mM) in a nutrient growth medium. The results revealed that exposure of various levels of Cu by 50 and 100 μM significantly (p < 0.05) reduced plant growth, biomass, chlorophyll contents, gaseous exchange attributes, and damaged ultra-structure of chloroplast in C. capsularis seedlings. Furthermore, Cu toxicity also enhanced the production of malondialdehyde (MDA) which indicated the Cu-induced oxidative damage in the leaves of C. capsularis seedlings. Increasing the level of Cu in the nutrient solution significantly increased Cu uptake by the roots and shoots of C. capsularis seedlings. The application of CA into the nutrient medium significantly alleviated Cu phytotoxicity effects on C. capsularis seedlings as seen by plant growth and biomass, chlorophyll contents, gaseous exchange attributes, and ultra-structure of chloroplast. Moreover, CA supplementation also alleviated Cu-induced oxidative stress by reducing the contents of MDA. In addition, application of CA is helpful in increasing phytoremediation potential of the plant by increasing Cu concentration in the roots and shoots of the plants which is manifested by increasing the values of bioaccumulation (BAF) and translocation factors (TF) also. These observations depicted that application of CA could be a useful approach to assist Cu phytoextraction and stress tolerance against Cu in C. capsularis seedlings grown in Cu contaminated sites.

Barley ( Hordeum vulgare L.) is a major cereal grain and is known as a halophyte (a halophyte is a salt-tolerant plant that grows in soil or waters of high salinity). We therefore conducted a pot experiment to explore plant growth and biomass, photosynthetic pigments, gas exchange attributes, stomatal properties, oxidative stress and antioxidant response and their associated gene expression and absorption of ions in H. Vulgare . The soil used for this analysis was artificially spiked at different salinity concentrations (0, 50, 100 and 150 mM) and different levels of ascorbic acid (AsA) were supplied to plants (0, 30 and 60 mM) shortly after germination of the seed. The results of the present study showed that plant growth and biomass, photosynthetic pigments, gas exchange parameters, stomatal properties and ion uptake were significantly ( p < 0.05) reduced by salinity stress, whereas oxidative stress was induced in plants by generating the concentration of reactive oxygen species (ROS) in plant cells/tissues compared to plants grown in the control treatment. Initially, the activity of antioxidant enzymes and relative gene expression increased to a saline level of 100 mM, and then decreased significantly ( P < 0.05) by increasing the saline level (150 mM) in the soil compared to plants grown at 0 mM of salinity. We also elucidated that negative impact of salt stress in H. vulgare plants can overcome by the exogenous application of AsA, which not only increased morpho-physiological traits but decreased oxidative stress in the plants by increasing activities of enzymatic antioxidants. We have also explained the negative effect of salt stress on H. vulgare can decrease by exogenous application of AsA, which not only improved morpho-physiological characteristics, ions accumulation in the roots and shoots of the plants, but decreased oxidative stress in plants by increasing antioxidant compounds (enzymatic and non-enzymatic). Taken together, recognizing AsA's role in nutrient uptake introduces new possibilities for agricultural use of this compound and provides a valuable basis for improving plant tolerance and adaptability to potential salinity stress adjustment.

Through its impact on morphogenesis, light is the key environmental factor that alters plant structural development; however, the understanding how light controls plant growth and developmental processes is still poor and needs further research. For this purpose, a Petri dish and pot experiment was conducted to investigate the effects of different LEDs, i.e., white light (WL), red light (RL), blue light (BL), and orange light (OL) on morphology, gas-exchange parameters, and antioxidant capacity of Brassica napus. Compared with WL, RL significantly promoted plant growth and biomass, contents of photosynthetic pigments, and gas-exchange parameters in comparison to BL and OL. However, RL also helped decline malondialdehyde and proline contents and superoxide anion and peroxide production rate. In contrast, BL and OL significantly reduced plant growth and biomass, gas-exchange attributes and increased the activities of superoxide dismutase and peroxidase in Petri dish as well as in pot experiment. These results suggest that red light could improve plant growth in B. napus plants through activating gas-exchange attributes, reduce reactive oxygen species accumulation, and promote antioxidant capacity.

The supply of nutrients and proximate matter is insufficient to fulfil the dietary needs of the quickly expanding human population. Green leafy vegetables can prove economical sources of minerals, vitamins and fibers to overcome nutritional deficiencies. Five leafy vegetables (Brassica juncea, Spinacia oleracea, Trigonella foenum-graecum, Chenopodium album and Lactuca sativa) were collected from a horticulture garden and vegetable market for the evaluation of their proximate matter and nutritional composition. Their contents of proximate (moisture, ash, fats, fibers, carbohydrates and protein), minerals (Ca2+, K+ and P+) and anti-nutrients were examined using standard protocols. The contents of fats (0.43 mg g−1f.w.) in S. oleracea; fibers (0.8 mg g−1f.w.) in S. olerace; carbohydrates (0.89 mg g−1f.w.); in B. juncea, proteins (0.91 mg g−1f.w.) in L. sativa; and vitamin A (1.18 mg g−1f.w.) in C. album from the horticulture garden were high enough to meet the daily dietary requirements of adults. Tannins were higher in species collected from the market, which is toxic for human health. It is concluded that vegetables of horticulture garden grown in suitable environmental conditions possess better nutritional composition as compared to vegetables purchased from markets. However, a large-scale research is needed for the analysis of vitamins, minerals, antioxidants, anti-nutrients and heavy metals in leafy vegetables. Further research on ethnomedicinal attributes of leafy vegetables is recommended.

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