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Cadmium (Cd) contamination greatly hinders plant productivity. Nanotechnology offers a promising solution for Cd phytotoxicity. The novelty of this study lies in the limited research on the effects of nanoiron (Fe 3 O 4 NPs) in regulating Cd toxicity in oilseed crops. This study examined how Fe 3 O 4 NPs regulated the Cd-exposure in B. napus. Foliar spray of 10 mg L−1 Fe 3 O 4 NPs was applied to 50 μM Cd-stressed B. napus seedlings via leaf exposure in hydroponic system. Under Cd stress, Fe 3 O 4 NPs decreased the Cd-accumulation (25–37%) due to adsorption followed by more root Cd-immobilization, and increased the plant height (23–31%) and biomass (17–24%). These findings were directly correlated with better photosynthetic activity (chlorophylls, gas exchanges and photosynthetic efficiency), leaf stomata opening and nutrients accumulation (20–29%). Subcellular localization revealed that Fe 3 O 4 NPs enhanced the binding capacity of cell wall for Cd to hinder its entry into cell organalles and facilitated vacoular sequestration. Additionally, Fe 3 O 4 NPs decreased the oxidative stress (21–33%) and peroxidation of lipids (24–31%) by regulating the genes-associated to superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, glutathione reductase, reduced glutathione, phytochelation, chlorophyll synthesis and Cd-transporters. Fe 3 O 4 NPs protected plant roots from Cd-induced cell structural damages and cell death. Among studied parameters, ZD 635 exhibited greater tolerance to Cd stress when compared to ZD 622 cultivar. Findings revealed that Fe 3 O 4 NPs effectively mitigate Cd toxicity by improving the photosynthesis, antioxidant defense mechanisms, cellular protection, nutrients accumulation and limiting Cd accumulation. This research offers a benchmark for the practical applicability of Fe 3 O 4 NPs to enhance the quality of canola production in Cd-contaminated soils. [Display omitted] • Nanoiron inhibits Cd-accumulation and enhances growth traits under Cd stress. • Nanoiron enhances photosynthetic activity and nutrients acquisition under Cd stress. • Nanoiron regulates subcellular distribution of Cd and gene expression analysis. • Nanoiron minimizes Cd-aided oxidative stress and regulates antioxidants defense. • Nanoiron recovers Cd-induced cell death, ultrastrucural and cross-sectional damages. [ABSTRACT FROM AUTHOR]

Chromium (Cr) phytotoxicity affirmed the need of mitigation strategies to remediate polluted soils and restricts its accumulation in the food chains. Salicylic acid (SA) and silicon (Si) play pivotal roles in stimulating the plant performance and stress resilience. So far, their interactive effects against Cr-phytotoxicities are less known. Thus, we evaluated the beneficial roles of alone or/and combine applications of SA and Si in mitigating the toxic effects of Cr in the leaves and roots of rice (Oryza sativa) seedlings. Results indicated that SA (10 μM) and/or Si (5 μM) markedly retrieved the Cr (100 μM) induced toxicities by minimizing the Cr-accretion in both leaves and roots, enhancing the performance of light harvesting pigments (total chlorophylls and carotenoids), water retention and accumulation of osmolytes (water-soluble protein and total soluble sugars) and ultimately improved the growth and biomass. Additionally, SA and/or Si maintained the ionic balance by enhancing the nutrients transport, upregulated the ascorbate-glutathione (AsA-GSH) cycle enzymes, minimized the extra accumulation of reactive oxygen species (ROS) (H 2 O 2 and O 2 •‒), malondialdehyde (MDA), recovered the membrane stability and damages in cellular ultrastructure in Cr-stressed rice plants. Overall findings suggested that SA underpins Si in mitigating the Cr-induced phytotoxicities on the above-reported parameters and combined applications of SA and Si were more effective than alone treatments. The uptake or cellular accumulation of Cr, osmoprotectants level and antioxidant defense system against oxidative stress can be considered as key toxicity biomarkers for the safe cultivation of rice in Cr-contaminated soils. [Display omitted] • SA and/or Si supply reduces Cr-accumulation and improves plant growth and dry biomass. • Under Cr stress, SA and/or Si recovers photosynthesis, osmotic stress and minerals status. • SA and/or Si restricts Cr-induced electrolyte leakage, MDA and ROS accumulation. • SA and/or Si activates antioxidants and AsA-GSH cycle enzymes against excessive ROS. • SA supports Si in alleviating the Cr-toxicity and SA + Si were more effective than SA or Si. [ABSTRACT FROM AUTHOR]

In this review, we argue that there is much to be learned by transferring knowledge from research on lignocellulose degradation to that on plastic. Plastic waste accumulates in the environment to hazardous levels, because it is inherently recalcitrant to biological degradation. Plants evolved lignocellulose to be resistant to degradation, but with time, fungi became capable of utilising it for their nutrition. Examples of how fungal strategies to degrade lignocellulose could be insightful for plastic degradation include how fungi overcome the hydrophobicity of lignin (e.g. production of hydrophobins) and crystallinity of cellulose (e.g. oxidative approaches). In parallel, knowledge of the methods for understanding lignocellulose degradation could be insightful such as advanced microscopy, genomic and post-genomic approaches (e.g. gene expression analysis). The known limitations of biological lignocellulose degradation, such as the necessity for physiochemical pretreatments for biofuel production, can be predictive of potential restrictions of biological plastic degradation. Taking lessons from lignocellulose degradation for plastic degradation is also important for biosafety as engineered plastic-degrading fungi could also have increased plant biomass degrading capabilities. Even though plastics are significantly different from lignocellulose because they lack hydrolysable C-C or C-O bonds and therefore have higher recalcitrance, there are apparent similarities, e.g. both types of compounds are mixtures of hydrophobic polymers with amorphous and crystalline regions, and both require hydrolases and oxidoreductases for their degradation. Thus, many lessons could be learned from fungal lignocellulose degradation. [ABSTRACT FROM AUTHOR]

Heat shock transcription factors (Hsfs) play an important role in regulating heat stress response in plants. Our previous study found that there were 82 non-redundant Hsfs in wheat, 18 of which belonged to subclass A2. In this study, we cloned an A2 member, TaHsfA2-1 , which encoded a protein of 346 amino acid residues in wheat. The fusion protein TaHsfA2-1-GFP was localized in the nucleus under normal growth conditions. TaHsfA2-1 was expressed in nearly all the measured tissues, most highly in mature leaves. The expression level of TaHsfA2-1 can be enhanced by heat stress, PEG stress, and signal molecules such as H 2 O 2 and SA. Yeast cells transformed with TaHsfA2-1 improved thermotolerance compared to those with the empty vector. TaHsfA2-1-overexpressing Arabidopsis displayed a better growth state with more green leaves than wild-type seedlings after heat stress. Accordingly, the chlorophyll content and survival rate in the transgenic lines were higher than in the wild type, and relative conductivity in the transgenic lines was lower than in the wild type. Further research found that TaHsfA2-1-overexpressing Arabidopsis up-regulated the expression of some heat shock protein genes (Hsps) compared to wild type after heat stress. These results suggested that TaHsfA2-1 is a new gene that improves thermotolerance in plants by mediating the expression of Hsps. A functional gene was provided for molecular breeding in the subsequent research. [ABSTRACT FROM AUTHOR]