Pb-induced changes in roots of two cultivated rice cultivars grown in lead-contaminated soil mediated by smoke

Abstract

Nowadays, public concerns regarding deleterious effect of lead (Pb) is on rise due to its abundance and toxic effect on plants and other living organisms. In plants, it has no noticeable biological importance but can cause various morphological, physiological, and biochemical malfunctions. To evaluate the remediating potential of plant-derived smoke (Cymbopogon jwarancusa), a pot culture experiment was designed to investigate the physiological, biochemical, metabolic, and antioxidant parameters of roots in lead (0 (control), 500, 1000, and 1500 ppm)-contaminated soil. Under dark condition, seeds were primed in smoke solution with two dilutions (1:500 and 1:1000) for 24 h. With an increasing concentration of Pb stress, fresh and dry weight and total nitrogen and protein contents decreased significantly while an increase was observed in smoke-treated seed. With increasing Pb stress level, metabolites (i.e., proline, total soluble sugar, total soluble protein, glycine betaine), and antioxidants (i.e., superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, malonyldialdehyde, and HO), contents of roots were increased in non-treated (without smoke treatment) samples, whereas comparatively, a low level of alteration in aforementioned metabolites and antioxidative parameters was observed in the seeds treated with smoke solution. These results suggest a positive role of smoke in alleviating lead-induced changes in roots of two cultivated cultivars of rice grown in Pb-contaminated soil.

Physio-biochemical responses of apple-of-sodom [Calotropis procera (Aiton) W. T. Aiton] to vehicular pollution

“…Excessive accumulation of metals induces the generation of reactive oxygen species (ROS) that cause oxidative stress in plants (Kaur et al, 2015). To ease the detrimental effects of ROS under stress conditions, plants have developed antioxidant defense systems (Zouari et al, 2016;Akhtar et al, 2017) which restrains and reduces the oxidative damage, and enhances the stress resistance in plants (Suzuki et al, 2012). Moreover, sulphur dioxide (SO2), a highly detrimental pollutant in the vehicular emissions also causes the generation of ROS and rise in the activity of antioxidants (Li & Yi, 2012).…”

Plant-Derived Smoke Affects Biochemical Mechanism on Plant Growth and Seed Germination

“…In addition to previously discussed parameters, alleviation was further supported by increase in cell membrane stability of smoke primed rice seedlings compared to non-treated ones [ 40 ]. Furthermore, flooding stress tolerance [ 14 ] and reduction in the inhibitory effects of heavy metals on plant growth [ 15 ] are also well documented. This characteristic can be interpreted as plant-derived smoke is not only responsible for promoting plant growth but also strategically involved in protecting plants against abiotic stresses.…”

“…Furthermore, a supply of plant-derived smoke solutions during flooding stress led to the flooding recovery of soybean after the removal of water [ 14 ]. It reduced the inhibitory effects of heavy metal, drought, salinity, and high/low temperature stresses on plant growth [ 15 ]. These results indicated that plant-derived smoke is a growth enhancer, reducer of inhibitory effect of environmental stresses, and a possible plant-growth fertilizer.…”

Nitrogen Regulates the Grain Yield, Antioxidant Attributes, and Nitrogen Metabolism in Fragrant Rice Grown Under Lead-Contaminated Soil

“…For example, Rao et al (2018) suggested that seeds with ultrasonic treatment improved the content of proline and soluble protein and enhanced the activities of SOD, CAT, and ascorbate peroxidase under Pb toxicity, which ultimately increased grain yield. Akhtar et al (2017) indicated that smoke could lessen Pb stress in two rice cultivars grown in Pbcontaminated soil. Nitrogen (N) is one of the important nutrients for plant growth, and N fertilizer played an important role in regulating grain yield, protein content, and grain quality in rice (Ali et al 2020;Jiang et al 2019;Pan et al 2017a;Mo et al 2018Mo et al , 2019aMo et al , 2019b.…”