Chrysotile-Asbestos-Induced Damage in Panicum virgatum and Phleum pretense Species and Its Alleviation by Organic-Soil Amendment

Abstract

Asbestos is an industrially important microfiber present in cement industries and some mining sites and is very toxic to plant growth and development, but it has been neglected over the years. Therefore, this study was conducted to investigate the hazardous effects of asbestos on the growth and development of two important grass species (switchgrass and timothy grass). In order to mitigate the toxic effects of asbestos, a compost (bio-fertilizer) was also used. The asbestos soil samples were collected within a 10 km area of a cement factory. The results revealed that the asbestos-contaminated soils displayed a considerable increment in heavy metal uptake including chromium (Cr), manganese (Mn), vanadium (V), arsenic (As), and barium (Ba), which led to stunted plant growth. Consequently, the activities of antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) were stimulated to kept the redox balance under control. Among all the contaminated soils, the soil that was taken within a 0 Km area, closest to the cement factory, was the most toxic one. However, a compost amendment (25%) as a bio-fertilizer substantially reduced the toxic effects of asbestos fiber on the overall growth and development of plants, by reducing the metals’ uptake. Moreover, it was found that the roots of both grass species experienced higher heavy metal accumulation relative to the shoots. Collectively, it can be proposed that the studied grass species can be used for phytoextraction purposes, since both of them absorbed the heavy metals from the asbestos-contaminated soils.

Thiourea-Capped Nanoapatites Amplify Osmotic Stress Tolerance in Zea mays L. by Conserving Photosynthetic Pigments, Osmolytes Biosynthesis and Antioxidant Biosystems

“…Ca is also an obvious component of multiple plant signaling pathways, remarkably including the SOS-regulatory pathway, which manages the sequestration of Naþ from the cytosol into the vacuole [29]. Moreover, reduction in photosynthetic pigments in plants under salt stress is of common occurrence that has been reported in a wide variety of plants [30]. Salinity tends to inhibit the production of chlorophyll through the activation of the chlorophylytic enzyme (chlorophyllase) and chloroplast membrane degradation, the production of ROS and the inactivation of the Rubisco enzyme [31,32]; thus, a decline in the pigment of leaves damages the structure of the leaf by minimizing the chloroplast [33,34].…”

Exogenous Ca/Mg quotient reduces the inhibitory effects of PEG induced osmotic stress on Avena sativa L.

“…Drought stress is known as the most influential abiotic stress or environmental factor that inhibit plant growth and production. Drought exists either due to extremely less rainfall or significant distinction in the quantity of moisture, and is considered as substantial abiotic stress hindering agriculture (Nawaz et al, 2012;Saleem et al, 2022). Drought stress individually has appeared to be the most hazardous intimidation to global food security.…”

Assessment of phytoremediation potential of native plant species naturally growing in a heavy metal-polluted industrial soils

“…Absorption of Cd from the soil and its (re)distribution between roots and shoots is a highly regulated process where several key players are involved: metal transporters of the root cell plasma membrane, xylem and phloem loading/unloading and leaf/shoot sequestration and detoxification. Plants absorb cadmium through the roots, and there are several factors that can affect availability of cadmium to plants, such as above-mentioned pH, the rhizosphere, and organic acids (Ismael et al, 2019;Saleem et al, 2022). Cd affects plants by inhibiting photosynthesis and respiration, reducing water and nutrient uptake, altering gene and protein expression, inducing and inhibiting enzymes, enhancing accumulation of reactive oxygen species (ROS), enhancing lipid peroxidation, and disturbing metabolism (Semane et al, 2010;Faryal et al, 2022).…”