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Heavy metal pollution has become a significant concern as the world continues to industrialize, urbanize, and modernize. Heavy metal pollutants impede the growth and metabolism of plants. The bioaccumulation of heavy metals in plants may create chlorophyll antagonism, oxidative stress, underdeveloped plant growth, and reduced photosynthetic system. Finding practical solutions to protect the environment and plants from the toxic effects of heavy metals is essential for long-term sustainable development. The direct use of suitable living plants for eliminating and degrading metal pollutants from ecosystems is known as phytoremediation. Phytoremediation is a novel and promising way to remove toxic heavy metals. Plant growth-promoting rhizobacteria (PGPR) can colonize plant roots and help promote their growth. Numerous variables, such as plant biomass yield, resistance to metal toxicity, and heavy metal solubility in the soil, affect the rate of phytoremediation. Phytoremediation using the PGPR consortium can speed up the process and increase the rate of heavy metal detoxification. The PGPR consortium has significantly increased the biological accumulation of various nutrients and heavy metals. This review sheds light on the mechanisms that allow plants to uptake and sequester toxic heavy metals to improve soil detoxification. The present review aids the understanding of eco-physiological mechanisms that drive plant-microbe interactions in the heavy metal-stressed environment., (© 2024 Wiley‐VCH GmbH.)

Proso millet (Panicum miliaceum L.) is an annual thermophilic, drought-resistant, short-season C4 grass that is suitable for growing under the present changing meteorological conditions. However, water shortage can reduce plant production and hinder mineral nutrition in plants, including silicon, which is of crucial importance for grasses. Ultraviolet radiation can mitigate the impacts of water shortage, and therefore we examined the effects of moderate water shortage and reduced ultraviolet radiation on different leaf traits, including leaf levels of silicon and other elements, and plant biomass production. Moderate water shortage and ambient ultraviolet radiation did not affect the contents of photosynthetic pigments, while they reduced stomata density. Water shortage significantly decreased leaf light reflectance in the ultraviolet and violet regions. Leaf silicon, calcium, phosphorus, and sulphur levels were significantly lower with reduced water availability and significantly higher with reduced ultraviolet radiation. Leaf silicon levels ranged from 1.5% to 2.5% of leaf dry mass, with leaf calcium levels from 0.3% to 0.6%. Except for chlorine and potassium, the levels of these elements in the leaves were significantly positively related (p ≤ 0.05) to soil moisture levels. Water availability, but not ultraviolet radiation, significantly reduced living leaf biomass.

Talinum triangulare (Jacq.) Willd. is a traditional leafy vegetable used by tribal communities for ethnomedicinal and ethnoculinary preparations. This article reviews the current knowledge of its multiple uses, including pharmacological activities and nutritional composition. The literature survey shows that it has been traditionally useful in the treatment of several diseases, such as anaemia, diabetes, measles, and ulcers and the preparation of various traditional foods. Analysis of the literature on its phytochemicals shows its richness in bioactive compounds. Further, research also shows that this plant has antidiabetic, antiobesity, antitumor, antiulcer, hepatoprotective, and neuroprotective activities besides anti-inflammatory and antioxidant properties. Nutrient analysis of the plant reveals the presence of Ca, Zn, Fe, vitamins C and E, dietary fibre and protein in considerable quantities. The results of the pharmacological studies on the antidiabetic, antiulcer and anti-anaemic activities provide support in favour of its ethnomedicinal uses. The presence of bioactive compounds and pharmacological activities show the usefulness of this plant as a functional food., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Aluminium (Al) is toxic to most plants. Nevertheless, some species accumulate Al without showing toxicity symptoms. Previous studies have evidenced Al in chloroplasts of Al-accumulating species from the Cerrado vegetation in South America. We ask whether Al increases carbon assimilation through enhanced apparent efficiency of Rubisco. Seedlings of the Al-accumulator Qualea grandiflora (Vochysiaceae) were grown in nutrient solution with 0, 740, and 1480 μm Al. Growth parameters, relative leaf water content, Al concentration in organs, gas exchange and apparent carboxylation efficiency (measured from A/Ci curves) were evaluated for 60 days. Plants without Al showed no root growth, necrotic roots, low gas exchange rates, and decreased apparent carboxylation efficiency. Al-treated plants, however, showed new white roots and increased root biomass leading to higher leaf hydration, and apparent carboxylation efficiency was higher in these plants. Increased Al available in the nutrient solution increased Al accumulation in plant organs. Absence of Al compromised root integrity in Q. grandiflora, thus limiting leaf hydration. No positive direct effect of Al on Rubisco was evidenced in Al-treated plants., (© 2023 German Society for Plant Sciences, Royal Botanical Society of the Netherlands.)

Tea is the one of the most popular non-alcoholic caffeinated beverages in the world. Tea is produced from the tea plant (Camellia sinensis (L.) O. Kuntze), which is known to accumulate fluoride. This article systematically analyzes the literature concerning fluoride absorption, transportation and fluoride tolerance mechanisms in tea plants. Fluoride bioavailability and exposure levels in tea infusions are also reviewed. The circulation of fluoride within the tea plantation ecosystems is in a positive equilibrium, with greater amounts of fluoride introduced to tea orchards than removed. Water extractable fluoride and magnesium chloride (MgCl 2 ) extractable fluoride in plantation soil are the main sources of absorption by tea plant root via active trans-membrane transport and anion channels. Most fluoride is readily transported through the xylem as F - /F-Al complexes to leaf cell walls and vacuole. The findings indicate that tea plants employ cell wall accumulation, vacuole compartmentalization, and F-Al complexes to co-detoxify fluoride and aluminum, a possible tolerance mechanism through which tea tolerates higher levels of fluoride than most plants. Furthermore, dietary and endogenous factors influence fluoride bioavailability and should be considered when exposure levels of fluoride in commercially available dried tea leaves are interpreted. The relevant current challenges and future perspectives are also discussed. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.)