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In the current era of rapid industrialization, the foremost challenge is the management of industrial wastes. Activities such as mining and industrialization spill over a large quantity of toxic waste that pollutes soil, water, and air. This poses a major environmental and health challenge. The toxic heavy metals present in the soil and water are entering the food chain, which in turn causes severe health hazards. Environmental clean‐up and reclamation of heavy metal contaminated soil and water are very important, and it necessitates efforts of environmentalists, industrialists, scientists, and policymakers. Phytoremediation is a plant‐based approach to remediate heavy metal/organic pollutant contaminated soil and water in an eco‐friendly, cost‐effective, and permanent way. This review covers the effect of heavy metal toxicity on plant growth and physiological process, the concept of heavy metal accumulation, detoxification, and the mechanisms of tolerance in plants. Based on plants' ability to uptake heavy metals and metabolize them within tissues, phytoremediation techniques have been classified into six types: phytoextraction, phytoimmobilization, phytovolatilization, phytodegradation, rhizofiltration, and rhizodegradation. The development of research in this area led to the identification of metal hyper‐accumulators, which could be utilized for reclamation of contaminated soil through phytomining. Concurrently, breeding and biotechnological approaches can enhance the remediation efficiency. Phytoremediation technology, combined with other reclamation technologies/practices, can provide clean soil and water to the ecosystem. [ABSTRACT FROM AUTHOR]

Calcium-dependent protein kinase (CDPK) is member of one of the most important signalling cascades operating inside the plant system due to its peculiar role as thermo-sensor. Here, we identified 28 full length putative CDPKs from wheat designated as TaCDPK (1-28). Based on digital gene expression, we cloned full length TaCPK-1 gene of 1691 nucleotides with open reading frame (ORF) of 548 amino acids (accession number OP125853). The expression of TaCPK-1 was observed maximum (3.1-fold) in leaf of wheat cv. HD2985 (thermotolerant) under T2 (38 ± 3 °C, 2 h), as compared to control. A positive correlation was observed between the expression of TaCPK-1 and other stress-associated genes (MAPK6, CDPK4, HSFA6e, HSF3, HSP17, HSP70, SOD and CAT) involved in thermotolerance. Global protein kinase assay showed maximum activity in leaves, as compared to root, stem and spike under heat stress. Immunoblot analysis showed abundance of CDPK protein in wheat cv. HD2985 (thermotolerant) in response to T2 (38 ± 3 °C, 2 h), as compared to HD2329 (thermosusceptible). Calcium ion (Ca2+), being inducer of CDPK, showed strong Ca-signature in the leaf tissue (Ca—622 ppm) of thermotolerant wheat cv. under heat stress, whereas it was minimum (Ca—201 ppm) in spike tissue. We observed significant variations in the ionome of wheat under HS. To conclude, TaCPK-1 plays important role in triggering signaling network and in modulation of HS-tolerance in wheat. [ABSTRACT FROM AUTHOR]

Worldwide, millets are regarded as a nutri-grain; however, they are the least exploited. Pearl millet grain is abundant in health-beneficial nutrients, making it suitable as food and feed; though poor in bioavailability of micronutrients like iron (Fe) and zinc (Zn) due to abundance of anti-nutritional factors causing micronutrient deficiencies (MNDs). Crop biofortification has been used as one of the potential strategies to control micronutrient malnutrition, mainly Fe and Zn in a cost effective manners. Many in vivo and in vitro studies have advocated the negative impact of phytates, fibers and tannins on iron and zinc availability. The interaction between Fe, Zn and other minerals has also adverse impact on the bioaccessability and bioavailability of micronutrients. The efforts have been made to reduce anti-nutritional factors using different processing methods like pre-soaking of seeds, fermentation, heat treatment, snap heat, phytase treatment, etc. to improve the nutritional quality of the flour. Hydrothermal with infra-red treatment has been observed to be most effective in enhancing the availability of minerals. The screening of pearl millet germplasms in many studies indicated presence of sufficient variability for grain iron and zinc. Breeding, molecular and processing approaches should be followed to achieve micronutrient homeostasis and nutrient sustainability. [Display omitted] • Pearl millet flour is rich in macro- and micronutrients required for our balanced diet. • The bioavailability of Fe/ Zn is very low due to abundance of ANFs causing MNDs. • Phytase treatment, germination, fermentation, etc. enhances the bioavailability of Fe and Zn. • Wide-diversity has been observed in ANFs and nutrients in pearl millet germplasm. • Micronutrient homeostasis can be achieved through breeding and processing methods. [ABSTRACT FROM AUTHOR]

Heat stress causes oxidative bursts damaging the organelles and nascent proteins. Plants have inherited antioxidant defense system to neutralize the effect of reactive oxygen species. Superoxide dismutase provides first line of defense against the HS by regulating the accumulation of peroxide radicals inside the cells. Here, we report identification and cloning of putative manganese superoxide dismutase (Mn-SOD) gene of ~733 nt from wheat cv. HD2985 through de novo assembly. The gene was observed to localize on Chr 6D with a mitochondrial targeting peptide sequence and iron/manganese domain. We predicted 147 homologs of Mn-SOD in eukaryotes with diverse speciation nodes. A recombinant Mn-SOD protein of ~25.5 kDa was purified through heterologous expression system. Kinetics assay of recombinant protein showed optimum pH of 8.0, optimum temperature of 35 °C and K m and V max values of 1.51 μM and 9.45 U/mg proteins, respectively. Maximum expression and activity of Mn-SOD was observed in leaves from Raj3765, as compared to stem and spike during milky-ripe stage under differential HS. In gel activity assay showed the appearance of all the three isoforms of SOD in thermotolerant cv. under HS. Mn-SOD, being active at pivotal position, can be also used as potential biochemical marker in wheat breeding program. • Cloned putative Mn-SOD of ~733 nt from wheat cv. HD2985 through de novo assembly. • Predicted 147 homologs of Mn-SOD in eukaryotes with diverse speciation nodes. • Recombinant Mn-SOD protein of ~25.5 kDa was purified from E. coli. • Kinetics of recombinant protein showed optimum pH, temperature, K m and V max of 8.0, 35 °C, 1.51 μM and 9.45 U/mg proteins. • Mn-SOD was observed to be potential biochemical marker for wheat breeding program. [ABSTRACT FROM AUTHOR]

Terminal heat stress has detrimental effect on the growth and yield of wheat. Very limited information is available on heat stress-associated active proteins (SAAPs) in wheat. Here, we have identified 159 protein groups with 4271 SAAPs in control (22 ± 3 °C) and HS-treated (38 °C, 2 h) wheat cvs. HD2985 and HD2329 using iTRAQ. We identified 3600 proteins to be upregulated and 5825 proteins to be downregulated in both the wheat cvs. under HS. We observed 60.3% of the common SAAPs showing upregulation in HD2985 (thermotolerant) and downregulation in HD2329 (thermosusceptible) under HS. GO analysis showed proton transport (molecular), photosynthesis (biological), and ATP binding (cellular) to be most altered under HS. Most of the SAAPs identified were observed to be chloroplast localized and involved in photosynthesis. Carboxylase enzyme was observed most abundant active enzymes in wheat under HS. An increase in the degradative isoenzymes (α/β-amylases) was observed, as compared to biosynthesis enzymes (ADP-glucophosphorylase, soluble starch synthase, etc.) under HS. Transcript profiling showed very high relative fold expression of HSP17, CDPK, Cu/Zn SOD, whereas downregulation of AGPase, SSS under HS. The identified SAAPs can be used for targeted protein-based precision wheat-breeding program for the development of 'climate-smart' wheat. [ABSTRACT FROM AUTHOR]

Heat stress has an adverse effect on the quality and quantity of agriculturally important crops, especially wheat. The tolerance mechanism has not been explored much in wheat and very few genes/ TFs responsive to heat stress is available on public domain. Here, we identified, cloned and characterized a putative TaHSFA6e TF gene of 1.3 kb from wheat cv . HD2985. We observed an ORF of 368 aa with Hsf DNA binding signature domain in the amino acid sequence. Single copy number of TaHSFA6e was observed integrated in the genome of wheat. Expression analysis of TaHSFA6e under differential HS showed maximum transcripts in wheat cv . Halna (thermotolerant) in response to 38 °C for 2 h during pollination and grain-filling stages, as compared to PBW343, HD2329 and HD2985. Putative target genes of TaHSFA6e ( HSP17 , HSP70 and HSP90 ) showed upregulation in response to differential HS (30 & 38 °C, 2 h) during pollination and grain-filling stages. Small HSP17 was observed most triggered in Halna under HS. We observed increase in the catalase, guaiacol peroxidase, total antioxidant capacity (TAC), and decrease in the lipid peroxidation in thermotolerant cvs . (Halna, HD2985), as compared to thermosusceptible (PBW343, HD2329) under differential HS. Multiple stresses (heat - 38 °C, 2 h, and drought - 100 mL of 20% polyethylene Glycol 6000) during seedling stage of wheat showed positive correlation between the expression of TaHSFA6e , putative targets ( HSP70 , HSP90 , HSP17 ) and TAC. Halna (thermotolerant) performed better, as compared to other contrasting cvs . TaHSFA6e TF can be used as promising candidate gene for manipulating the heat stress-tolerance network. [ABSTRACT FROM AUTHOR]

Wheat is a staple food worldwide and provides 40% of the calories in the diet. Climate change and global warming pose a threat to wheat production, however, and demand a deeper understanding of how heat stress might impact wheat production and wheat biology. However, it is difficult to identify novel heat stress associated genes when the genomic information is not available. Wheat has a very large and complex genome that is about 37 times the size of the rice genome. The present study sequenced the whole transcriptome of the wheat cv. HD2329 at the flowering stage, under control (22° ± 3°C) and heat stress (42°C, 2 h) conditions using Illumina HiSeq and Roche GS-FLX 454 platforms. We assembled more than 26.3 and 25.6 million high-quality reads from the control and HS-treated tissues transcriptome sequences respectively. About 76,556 (control) and 54,033 (HS-treated) contigs were assembled and annotated de novo using different assemblers and a total of 21,529 unigenes were obtained. Gene expression profile showed significant differential expression of 1525 transcripts under heat stress, of which 27 transcripts showed very high (>10) fold upregulation. Cellular processes such as metabolic processes, protein phosphorylation, oxidations-reductions, among others were highly influenced by heat stress. In summary, these observations significantly enrich the transcript dataset of wheat available on public domain and show a de novo approach to discover the heat-responsive transcripts of wheat, which can accelerate the progress of wheat stress-genomics as well as the course of wheat breeding programs in the era of climate change. [ABSTRACT FROM AUTHOR]

Abiotic stress leads to change in the expression and activities of number of proteins which are involved in defense mechanism against stresses. Qualitative and quantitative changes in proteins might play a role in signal transduction, antioxidative defence, heat shock, metal binding or osmolyte synthesis. Here, 22 wheat genotypes were screened for its cell membrane stability (CMS), out of which C-306 showed the maximum CMS value of 74%. Protein profiling revealed the expression of many new and existing proteins in C-306 cultivar compared to PBW343 under differential heat shock (HS). An altered protein expression was also observed in tolerant and susceptible cultivars at different stages of growth. Isoenzymic profiling revealed the expression of many new isoenzymes of ascorbate peroxidase and superoxide dismutase in C-306 compared to PBW343 in response to heat shock. A stage specific analysis showed the maximum activity of different antioxidant isoenzymes at pollination and seed hardening stages. SODs plays central role in regulating defense mechanism and need to be further characterized. [ABSTRACT FROM AUTHOR]

• Pearl millet is considered as 'nutri-cereal' because of high nutrient density. • Lipase is stable and versatile enzyme involved in diverse biological processes. • Lipase causes hydrolytic rancidity and off-odour development in pearl millet flour. • Identified 2180 putative lipase transcripts from pearl millet. • Physiochemical treatments reduce the lipase activity in pearl millet flour. Pearl millet is considered as 'nutri-cereal' because of high nutrient density of the seeds. The grain has limited use because of low keeping quality of the flour due to the activities of rancidity causing enzymes like lipase, lox, pox and PPO. Among all the enzymes, lipase is most notorious because of its robust nature and high activity under different conditions. we have identified 2180 putative transcripts showing homology with different variants of lipase precursor through transcriptome data mining (NCBI BioProject acc. no. PRJNA625418). Lipase plays dual role of facilitating the germination of seeds and deteriorating the quality of the pearl millet flour through hydrolytic rancidity. Different physiochemical methods like heat treatment, micro oven, hydrothermal, etc. have been developed to inhibit lipase activity in pearl millet flour. There is further need to develop improved processing technologies to inhibit the hydrolytic and oxidative rancidity in the floor with enhanced shelf-life. [ABSTRACT FROM AUTHOR]