Explore the vast range of titles available.

Improving cadmium (Cd) tolerance and phytoremediation efficiency in hyperaccumulator plants is a critical scientific issue in environmental remediation. Remediation performance is often constrained by physiological bottlenecks, including insufficient tolerance to high Cd stress and low heavy metal accumulation capacity. Against this background, exploring effective strategies to enhance the phytoremediation efficiency of hyperaccumulators has important theoretical and practical value. Using L. (amaranth) cultivar R104, quercetin (0, 5, 10, 20 mg·L ; denoted as CK, Q1, Q2, and Q3, respectively) was applied under varying Cd levels (0, 4, 20 mg·kg⁻¹; denoted as Cd0, Cd4, and Cd20, respectively), and physiological traits, antioxidant responses, and key metabolites were comprehensively assessed. The results demonstrate that exogenous quercetin markedly alleviated Cd induced toxicity, with the Cd20Q2 treatment showing the most pronounced mitigation effect. Compared the Cd stressed control without quercetin, electrolyte leakage was reduced by 49.5%, chlorophyll content increased by 17.7%, and the plant's Cd enrichment capacity was significantly enhanced, with the aboveground enrichment factor reaching 7.02. It revealed that quercetin activated the phenylpropanoid flavonoid pathway, promoting the synthesis of endogenous flavonoids (notably quercetin and kaempferol) and increasing glutathione (GSH) levels and overall antioxidant capacity. This created a synergistic mechanism of \"endogenous flavonoid enhancement coupled with exogenous quercetin supplementation\". Concurrently, the enhanced accumulation of GSH and related metabolites facilitated Cd chelation and detoxification, thereby reducing oxidative injury at the cellular level. In summary, exogenous quercetin improves Cd tolerance and remediation efficiency in amaranth by regulating flavonoid metabolism and strengthening GSH mediated detoxification. These findings provide theoretical and practical support in heavy metal remediation strategies.

Phytoextraction assisted by plant growth regulators (PGRs) is gaining popularity in phytoremediation applications. A pot experiment was conducted to compare the effects of foliar applications of 11 PGRs, including Indole-3-acetic acid (IAA), Indole-3-butyric acid (IBA), diethyl aminoethyl hexanoate (DA-6), 6-Benzylaminopurine (6-BA), 1-naphthylacetic acid (NAA), Abscisic acid (ABA), 2,4-Dichlorophenoxyacetic acid (2,4-D), Ethrel (ETH), Brassinolide (BR), Gibberellin (GA3), and Compound sodium nitrophenolate (CSN) on plant development, chlorophyll content, antioxidant enzyme activities, Cd phytoextraction capacity and micro-distribution of Amaranthus hypochondriacus L. grown in Cd contaminated soil. The effect on biomass yield was dependent on the PGRs type, with IBA being the most efficient. The addition of PGRs increased Cd extraction efficiency, with their effect decreasing in the order: IAA > DA-6 > IBA > 2,4-D > 6-BA > NAA > BR > CSN > ETH > GA3 > ABA. Application of PGRs increased Cd concentrations in leaves and stems but reduction was found in roots (except for 2,4-D). Exogenous PGRs increased the activities of stress ameliorating enzymes (SOD and CAT) and led to a reduction in MDA (malondialdehyde) concentration. In leaves, scanning electron microscope-Energy dispersive spectrometer (SEM–EDS) confirmed that application of IBA or DA-6 further fixed more Cd in upper and lower epidermal cells, which might relate to more Cd migration from roots to shoots in Amaranthus hypochondriacus L. These findings suggest that the treatment with IBA or DA-6 appears to be optimal for enhancing the phytoextraction efficiency of Amaranthus hypochondriacus L. in Cd contaminated soil.

Grain Amaranth is the most promising C4 dicotyledonous pseudocereal and is distributed globally. It has an excellent nutritional profile and adaptability against a broad range of environmental factors. These traits have renewed the interest of researchers and breeders in exploring this underutilized orphan crop. The present study aimed to validate the genome-wide SSR to assess the genetic diversity among 94 Amaranthus hypochondriacus accessions using 57 genomic SSR (g-SSR) markers developed in-house. A total of 36 g-SSRs were recorded as polymorphic and amplified 138 alleles, with an average of 3.83 alleles per locus. Major allele frequency ranged from 0.29 to 0.98, with an average of 0.63 per marker. The expected heterozygosity ranged from 0.03 to 0.81, with an average of 0.46 per locus. Polymorphism information content (PIC) ranged from 0.03 to 0.79, with an average of 0.40, indicating a high level of polymorphism across amaranth accessions. Population structure analysis resulted into two major genetic clusters irrespective of their geographical origin, which suggests there may be sharing of common genomic regions across the accessions. High allelic frequency and heterozygosity levels indicate significant genetic variability in the germplasm, which can be further used in future breeding programs.

Amaranth species represent a diverse group of plants. Many of them are a rich source of secondary metabolites with many positive biological effects. Total phenolic, total flavonoid and rutin content, antioxidant activity against superoxide and hydroxyl radicals, FRAP (Ferric-reducing ability of plasma) assay and DPPH (2,2-Diphenyl-1-picrylhydrazyl) radical scavenging assay were determined in ethanol extracts of dried leaves of the new Slovak amaranth varieties ‘Pribina’ and ‘Zobor’. The amount of total phenolic substances (‘Pribina’ GAE 38.3 mg.g−1 DM and ‘Zobor’ GAE 26.1 mg.g−1 DM), content of total flavonoids (‘Pribina’ QE 26.5 mg.g−1 DM and ‘Zobor’ QE 20.3 mg.g−1 DM) and rutin (‘Pribina’ 50.8 mg.g−1 DM and ‘Zobor’ 15.2 mg.g−1 DM) were higher in the variety ‘Pribina’, compared to the variety ‘Zobor’. A statistically higher antioxidant activity against superoxide radical (1.63%·mg−1g−1 DM), hydroxyl radical (3.20%.mg−1g−1 DM), FRAP assay (292.80 µmol.L−1·mg−1.g−1 DM) and DPPH (54.2 ± 1.78 µg.mL−1 DM) were detected in the ‘Pribina’ variety. Antiradical and antioxidant activities of both extracts showed high positive correlations in relation to the content of total phenolic substances, total flavonoids and rutin. Amaranth is an undemanding crop on specific environmental conditions and is resistant to abiotic and biotic stress.

Seed oil, pressed oil, and pulp oil from three varieties of Amaranthus hypochondriacus, Lera, Gelios, and Khar′kovskii-1, introduced into Uzbekistan were characterized for the first time. The contents of oil in seeds and squalene in pressed oils did not differ significantly. These parameters in the introduced variety Khar′kovskii-1 were slightly less than those in the analogous varieties growing in the Russian Federation (RF). It was found that pressed oils and pulp oils contained different sets of fatty acids (FAs). Pressed oil of the introduced variety Lera differed from that of the analogous European variety by higher contents of monoenoic and lower contents of polyenoic FAs.

A. hypochondriacus leaves contained ample phytopigments including betalain, anthocyanin, β-xanthin, β-cyanin, and bioactive phytochemicals of interest in the industry of food. We have been evaluating the possibility of utilizing phytopigments of amaranth and bioactive constituents for making drinks. Therefore, we evaluated bioactive phytopigments and compounds including the potentiality of antioxidants in A. hypochondriacus leaves. A. hypochondriacus leaves have abundant protein, carbohydrates, and dietary fiber. We found considerable levels of inorganic minerals including magnesium, calcium, potassium (3.88, 3.01, 8.56 mg g −1 ), zinc, manganese, copper, iron (16.23, 15.51, 2.26, 20.57 µg g −1 ), chlorophyll b , chlorophyll ab chlorophyll a (271.08, 905.21, 636.87 μg g −1 ), scavenging capacity of radicals (DPPH, ABTS + ) (33.46, 62.92 TEAC μg g −1 DW), total polyphenols (29.34 GAE μg g −1 FW), β-xanthin, betalain, β-cyanin (584.71, 1,121.93, 537.21 ng g −1 ), total flavonoids (170.97 RE μg g −1 DW), vitamin C, β-carotene, carotenoids (184.77, 82.34, 105.08 mg 100 g −1 ) in A. hypochondriacus leaves. The genotypes AHC6, AHC4, AHC11, AHC5, and AHC10 had a good scavenging capacity of radicals. Polyphenols, phytopigments, flavonoids, and β-carotene of A. hypochondriacus had potential antioxidant activity. Extracted juice of A. hypochondriacus can be an ample source of phytopigments and compounds for detoxification of reactive oxygen species (ROS) and attaining nutritional and antioxidant sufficiency.

Background Grain amaranth ( Amaranthus hypochondriacus ) is a nutri-dense pseudocereal with dual-purpose potential as both grain and leafy vegetable. The exploration of grain amaranth types as leafy green could be useful in diversifying food systems, cropping systems and enhancing amaranth germplasm resources. The systematic nutritional profiling and multivariate analysis of grain amaranth leaves is limited, constraining targeted breeding efforts to improve nutritional quality. To establish its breeding potential for nutritious leafy greens, underscoring the compositional diversity of mineral nutrients and heavy metals accumulation in grain amaranth germplasm is vital. Results Plants were grown in an augmented randomized block design, and nutrient profiling was performed using digestion-based methods and microwave plasma atomic emission spectroscopy (MP-AES). Significant genetic variations were observed for essential mineral nutrients and heavy metals concentrations. Exotic accession EC519523 exhibited superior N and P content, while indigenous collections IC42356 and IC47434 showed promise for K-related nutritional quality. Vegetable checks, Arka Neelachal Bainishi and Arka Neelachal Ruchitha, along with grain type accessions, displayed potential for Fe and Mn biofortification. Notably, the comparative analysis of heavy metals with corresponding FAO/WHO permissible limits depicted significant genotypic variations where several accessions remained within limits, while the mean Cd and Pb values exceeded the referenced permissible thresholds. These findings indicated that suitability for consumption should therefore be considered genotype-dependent rather than universally safe. Multivariate analyses revealed five principal components explaining > 80% of the total variation, while cluster analysis grouped accessions into five nutritional clusters. These results enabled the scope of selecting ideal parents from diverse clusters for escalating breeding for nutritional and food security. Strong correlations between macro- and micronutrients indicated shared uptake pathways. Conclusions These findings highlighted the scope of developing Amaranthus hypochondriacus cultivars with dual-purpose value and offered the opportunities for diet diversification, biofortification, and sustainable food security. The results necessitated the need of further multi-location experiments to fetch a better understanding of breeding nutritious cultivars having level of heavy metals within permissible limits, and underscoring the trade-offs between leaf and grain yield in grain amaranths.

Amaranth, a gluten-free pseudo-cereal, is grown, cultivated, and adapted in diverse ecological zones all over the world. In recent years, increased attention has been paid on its nutritional eminence, particularly in terms of its seed protein, which specifically contains high levels of the essential amino acids. This important food and nutritional security crop’s gene pool, which is diverse, needs to be characterized and genotyped in order to broaden its genetic base and to boost production. Genotyping by sequencing data of diverse germplasm serve useful tool for identification of important candidate genes associated with important traits of plants. In the present study, genotyping-by-sequencing (GBS) approach was used to characterize a genetically diverse collection of 192 Amaranth accessions. This resulted in an estimated 41,931 single-nucleotide polymorphisms (SNPs) segregating across the entire collection and several thousand SNPs segregating within every accession. A model-based population structure analysis reveals the presence of three subpopulations among the Amaranth accessions, which are in parallel with the results of phylogenetic analysis. A total of 1796 gene ontology (GO) terms were assigned to SNP-carrying genes for three main categories: biological process, cellular component, and molecular function. High-throughput genotyping and sequencing data generated, will be very useful not only for breeders for further enhancement of Amaranth but also for molecular biologists for isolation and identification of nutritionally important genes from Amaranth, which can be used for biofortification programs.

Micronutrient malnutrition poses a global challenge, highlighting the need for biofortified crops with enhanced mineral density. Grain amaranth ( Amaranthus hypochondriacus ), a nutrient-rich pseudocereal, offers high levels of essential minerals, yet its genetic basis for mineral accumulation remains poorly understood. We evaluated 192 diverse accessions across two contrasting environments for calcium (Ca), iron (Fe), magnesium (Mg), and zinc (Zn) content, which varied from 90.5 to 249.7 mg/100 g (1.8-fold) for Ca, 6.8–35.7 mg/100 g (5.2-fold) for Fe, 182.2–471.7 mg/100 g (2.6-fold) for Mg, and 2.6–9.2 mg/100 g (3.6-fold) for Zn. High broad-sense heritability (H² ≥ 0.87) and substantial genetic advance confirmed strong genetic control and scope for selection. A multi-locus genome-wide association study using 41,931 SNPs identified 368 significant associations, of which 25 environmentally stable marker trait associations (MTAs) were detected across traits. Candidate gene analysis revealed 92 putative genes related to mineral homeostasis, and expression profiling validated functional relevance of key candidates. This study provides a comprehensive genomic framework for marker-assisted breeding of biofortified amaranth cultivars with enhanced mineral density.

Background The WRKY gene family plays a significant role in plant growth, development, and responses to biotic and abiotic stresses. However, the role of the WRKY gene family has not been reported in Amaranthus hypochondriacus . This study presents a comprehensive genome-wide analysis of the WRKY gene family in grain amaranth ( A. hypochondriacus L. ), a resilient crop known for its high nutritional value and adaptability to challenging environments. Results In this study, 55 WRKY genes (AhyWRKY1-55) were identified in A. hypochondriacus and distributed unevenly across 16 scaffolds. Of these, 50 contained conserved WRKY domains and were classified into three main groups. Group II was further divided into five subgroups (IIa-IIe) based on phylogenetic analysis, with each clade being well supported by conserved motifs. Additionally, the gene structure analysis revealed variations in exon-intron organization. In contrast, motif analysis showed the presence of conserved domains that were similar within the group but differed between groups, suggesting their functional diversity. Cis-acting elements related to plant growth and development and light, hormones, and stress responses were identified. Synteny analysis revealed that 34 (61.8%) of the genes originated from tandem duplication, indicating the role of tandem duplication in the expansion of the A. hypochondriacus WRKY gene family. Protein-protein interaction analysis suggested that AhyWRKY3, AhyWRKY27, AhyWRKY28, AhyWRKY36, and AhyWRKY52 were hub genes involved in the complex protein interaction network. Using in silico and real-time quantitative PCR, expression analysis revealed tissue- and condition-specific expression patterns of AhyWRKY genes. Notably, under drought stress, AhyWRKY39 , AhyWRKY40 , AhyWRKY54 , and AhyWRKY01 showed increased expression, while under salt stress, AhyWRKY40 , AhyWRKY54 , AhyWRKY39 , AhyWRKY49 , and AhyWRKY8 were upregulated at 30 days, suggesting that these genes may play key role in response to salinity stress. Conclusions The present study provides valuable insights into the organization and evolutionary patterns of the WRKY gene family in amaranth. It also identifies putative candidate WRKY genes that may play a role in conferring drought and salt tolerance. Overall, this study lays a foundation for further functional validation of these WRKY candidate genes, facilitating their exploitation in the amaranth genetic improvement programs to develop stress-resilient varieties.