Amaranth Plants Research Articles

Effect of single or sequential POST herbicide applications on seed production and viability of glyphosate-resistant Palmer amaranth (Amaranthus palmeri) in dicamba- and glyphosate-resistant soybean

AbstractGlyphosate-resistant (GR) Palmer amaranth is a troublesome weed that can emerge throughout the soybean growing season in Nebraska and several other regions of the United States. Late-emerging Palmer amaranth plants can produce seeds, thus replenishing the soil seedbank. The objectives of this study were to evaluate single or sequential applications of labeled POST herbicides such as acifluorfen, dicamba, a fomesafen and fluthiacet-methyl premix, glyphosate, and lactofen on GR Palmer amaranth control, density, biomass, seed production, and seed viability, as well as grain yield of dicamba- and glyphosate-resistant (DGR) soybean. Field experiments were conducted in a grower’s field infested with GR Palmer amaranth near Carleton, NE, in 2018 and 2019, with no PRE herbicide applied. Acifluorfen, dicamba, a premix of fomesafen and fluthiacet-methyl, glyphosate, or lactofen were applied POST in single or sequential applications between the V4 and R6 soybean growth stages, with timings based on product labels. Dicamba applied at V4 or in sequential applications at V4 followed by R1 or R3 controlled GR Palmer amaranth 91% to 100% at soybean harvest, reduced Palmer amaranth density to as low as 2 or fewer plants m−2, reduced seed production to 557 to 2,911 seeds per female plant, and resulted in the highest soybean yield during both years of the study. Sequential applications of acifluorfen, fomesafen and fluthiacet premix, or lactofen were not as effective as dicamba for GR Palmer amaranth control; however, they reduced seed production similar to dicamba. On the basis of the results of this study, we conclude that dicamba was effective for controlling GR Palmer amaranth and reduced density, biomass, and seed production without DGR soybean injury. Herbicides evaluated in this study had no effect on Palmer amaranth seed viability.

Predominance of Metabolic Resistance in a Six-Way-Resistant Palmer Amaranth (Amaranthus palmeri) Population.

Evolution of multiple herbicide resistance in Palmer amaranth across the United States is a serious challenge for its management. Recently, a Palmer amaranth population (KCTR; Kansas Conservation Tillage Resistant) from a long-term conservation tillage research project in Kansas, United States, was found uncontrolled by several commonly used herbicides. Importantly, this field did not have a history of repeated use of some of the herbicides for which the KCTR Palmer amaranth population showed lack of control. The objectives of this study were to confirm the evolution of multiple resistances and determine possible mechanism(s) of resistance in KCTR Palmer amaranth plants. In response to post-emergence application, 28–100% of KCTR Palmer amaranth survived field recommended rates of 2,4-D, ALS-, PS II-, EPSPS-, PPO-, HPPD-inhibitor herbicides, or tank- or pre-mixture of PS II- and HPPD-inhibitor herbicides, confirming evolution of six-way resistance in this Palmer amaranth population. However, this population was found susceptible to the PS I- and glutamine synthetase inhibitor herbicides. Chlorsulfuron-, imazethapyr-, and atrazine-resistant plants did not show any previously reported mutation in ALS and psbA genes, the target sites of these herbicides, respectively. However, the survivors of glyphosate treatment showed amplification of EPSPS gene (up to 88 copies). The KCTR plants pretreated with cytochrome P450 or GST inhibitors along with atrazine, 2,4-D, lactofen, or mesotrione had significantly less biomass accumulation than those treated with herbicides alone. Plants treated with P450 inhibitor followed by imazethapyr showed moderate reduction of biomass in KCTR which was statistically similar to a susceptible Palmer amaranth population treated with imazethapyr. These results suggest predominance of metabolic resistance possibly mediated by cytochrome P450 and GST enzyme activity that may have predisposed the KCTR Palmer amaranth population to evolve resistance to multiple herbicides. This is the first report of evolution of six-way resistance in a single Palmer amaranth population. Appropriate management strategies, including integration of cultural, and mechanical, and herbicide mixtures, are warranted to control such Palmer amaranth populations.

Evaluation of the Nutrient Composition, In Vitro Fermentation Characteristics, and In Situ Degradability of Amaranthus caudatus, Amaranthus cruentus, and Amaranthus hypochondriacus in Cattle.

Simple SummaryThe amaranth plants, one of the crops that can grow in poor soil and areas with extreme weather conditions—high temperature and limited rainfall—showed high potential feed value as forage for ruminants. An extensive study will help extend its utilization as an alternative protein and fiber feed source in cattle feeding. In this study, the nutrient compositions of the three different species of amaranth, Amaranthus caudatus, A. cruentus, and A. hypochondriacus, were evaluated. Rumen fluid was incubated with the amaranth plants to evaluate fermentation characteristics (total gas production, total volatile fatty acids concentration, pH, and ammonia concentration). There were no differences among the different amaranth species, but all amaranth showed favorable fermentation values. The effective degradabilities of dry matter and crude protein of the amaranth forages were also determined. Compared to other studies, the effective degradabilities of dry matter (33–56%) and crude protein (27–59%) of the amaranth were lower; these results could be due to the maturity stage at which the forages were harvested. In terms of chemical composition, the amaranth forages showed better nutritive value than the locally produced forages in Chungcheong province of Korea. The amaranth forages showed 11.95–14.19% crude protein (CP), 45.53–70.88% neutral detergent fiber (NDF), and 34.17–49.83% acid detergent fiber (ADF) contents. The high nutrient composition, highly effective degradability of dry matter, and crude protein coupled with the favorable fermentation characteristics suggest that the amaranth forages showed good to excellent feed quality to cattle.The amaranth plants showed high potential feed value as forage for ruminants. An in-depth study of this plant, particularly in cattle, will help extend its utilization as an alternative protein and fiber feed source in cattle feeding. In this study, the nutrient compositions of three different species of amaranth, Amaranthus caudatus L., Amaranthus cruentus L., and Amaranthus hypochondriacus L.—two varieties for each species, A.ca 74, A.ca 91, A.cu 62, A.cu 66, A. hy 30, and A. hy 48—were evaluated. The in vitro technique was used to evaluate the fermentation characteristics such as total gas production, total volatile fatty acids (VFA) concentration, pH, and ammonia concentration of the rumen fluid. Moreover, the effective degradabilities of dry matter (EDDM) and crude protein (EDCP) of the amaranth forages were determined through in situ bag technique. The amaranth forages: A. caudatus, A. cruentus, and A. hypochondriacus showed better nutritive value than the locally produced forages in Chungcheong province of Korea. The CP of the amaranth ranged from 11.95% to 14.19%, and the neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents ranged from 45.53% to 70.88% and 34.17% to 49.83%, respectively. Among the amaranth varieties, A. hypochondriacus 48 showed the most excellent ruminant feed nutrient quality (CP, 14.19%; NDF, 45.53%; and ADF, 34.17%). The effective degradabilities of dry matter (EDDM; 33–56%) and crude protein EDCP (27–59%) of the amaranth were lower compared to other studies, which could be due to the maturity stage at which the forages were harvested. Nonetheless, A. hypochondriacus 48 showed the highest EDDM (56.73%) and EDCP (59.09%). The different amaranth species did not differ greatly in terms of total VFA concentration or molar proportions, total gas production, or ammonia-N concentration. The high nutrient composition, and highly effective degradability of dry matter and crude protein, coupled with the favorable fermentation characteristics, suggest that the amaranth forages showed good to excellent feed quality for cattle.

A Review of Recent Studies on the Antioxidant Activities of a Third-Millennium Food: Amaranthus spp.

Amaranth (Amaranthus spp.) plant commonly refers to the sustainable food crop for the 21st century. The crop has witnessed significant attention in recent years due to its high nutritional value and agronomic advantages. It is a relatively well-balanced cosmopolitan food that is a protector against chronic diseases. Usually, the antioxidant activities of amaranth are held responsible for its defensive behavior. Antioxidant activity of plants, generally, is attributed to their phytochemical compounds. The current interest, however, lies in hydrolysates and bioactive peptides because of their numerous biological functions, including antioxidant effect. While the importance of bioactive peptides has been progressively recognized, an integrated review of recent studies on the antioxidant ability of amaranth species, especially their hydrolysates and peptides has not been generated. Hence, in this review, we summarize studies focused on the antioxidant capacity of amaranth renewal over the period 2015–2020. It starts with a background and overall image of the amaranth-related published reviews. The current research focusing on in vitro, in vivo, and chemical assays-based antioxidant activity of different amaranth species are addressed. Finally, the last segment includes the latest studies concerning free radical scavenging activity and metal chelation capacity of amaranth protein hydrolysates and bioactive peptides.

Amarant (Amaranthus cruentus L.) Bitkisine Değişik Oranlarda Uygulanan Leonardit Dozunun Su-Verim İlişkilerine Etkisi

Bu çalışmanın amacı farklı dozlarda leonardit uygulamasının Amarant bitkisinin su-verim ilişkilerine etkisini incelemektir. Araştırma Kahramanmaraş Sütçü İmam Üniversitesi Ziraat Fakültesi araştırma alanlarında saksı denemesi olarak yürütülmüştür. Araştırmada 5 farklı leonardit konusu (L2, L3, L4, L5, L6) her saksıda bir bitki olacak şekilde 18 tekerrüre göre düzenlenmiştir. Tesadüf parselleri deneme desenine göre düzenlenen çalışma 90 adet saksıyla yürütülmüştür. Toprak nem değerleri Time Domain Reflectometry (TDR) ile ölçülmüştür. Bitkilere yetişme dönemi boyunca 75.64 ile 82.99 L aralığında su verilmiştir. Su kullanım etkinliği (WUE) 0.28 ile 0.63 g L-1 aralığında bulunurken, sulama suyu etkinliği (IWUE) 0.40 ile 0.97 g L-1 aralığında bulunmuştur. Bu çalışmada bitki-verim tepki etmeni 1.54 olarak bulunmuştur. Çalışmadan elde edilen sonuçlara en yüksek verim, bin dane ağırlığı, bitki boy ve salkım boy değeri L6 konusundan sırasıyla 72.41 g adet-1, 0.75 g, 92.66 cm ve 21.66 cm olarak bulunmuştur. En düşük verim, bin dane ağırlığı, bitki boyu ve salkım uzunluğu değeri sırasıyla L3 konusunda 29.94 g adet-1, L4 konusunda 0.54 g, L2 konusunda 72.5 cm ve L2 konusunda 13 cm olarak bulunmuştur.

Using Amaranthus green proteins as universal biosurfactant and biosorbent for effective enzymatic degradation of diverse lignocellulose residues and efficient multiple trace metals remediation of farming lands

Improving biomass enzymatic saccharification is effective for crop straw utilization, whereas phytoremediation is efficient for trace metal elimination from polluted agricultural soil. Here, we found that the green proteins extracted from Amaranthus leaf tissue could act as active biosurfactant to remarkably enhance lignocellulose enzymatic saccharification for high bioethanol production examined in eight grassy and woody plants after mild chemical and green-like pretreatments were performed. Notably, this study estimated that total green proteins supply collected from one-hectare-land Amaranth plants could even lead to additional 6400–12,400 tons of bioethanol, being over 10-fold bioethanol yield higher than those of soybean seed proteins and chemical surfactant. Meanwhile, the Amaranth green proteins were characterized as a dominated biosorbent for multiple trace metals (Cd, Pb, As) adsorption, being 2.9–6 folds higher than those of its lignocellulose. The Amaranth plants were also assessed to accumulate much more trace metals than all other plants as previously examined from large-scale contaminated soils. Furthermore, the Amaranth green proteins not only effectively block lignin to release active cellulases for the mostly enhanced biomass hydrolyzes, but also efficiently involve in multiple chemical bindings with Cd, which should thus address critical issues of high-costly biomass waste utilization and low-efficient trace metal remediation.

The innovative bio-inspired fabrication of the cheap cross-linked cellulose/graphene oxide/ZnO bio-nanopolymer and its high catalytic performance

Molybdenum complex was immobilized on the extracted cellulose from Palmer amaranth plant (CLCSbMo). Then, by addition of graphene oxide/ZnO bio-nanocomposite to CLCSbMo, rGO/ZnO@CLCSbMo bio-nanopolymer was produced. It was characterized by SEM, FT-IR, TGA, DTA, XRD and EDAX. Its catalytic activity was investigated on the oxidation of alcohols and corresponded aldehydes and ketones were obtained with high conversions and excellent selectivities. This heterogeneous catalyst was recycled and data were shown the high stability and durability after five runs.

МЕТАБОЛИТЫ АВТОТРОФНЫХ И ГЕТЕРОТРОФНЫХ ЛИСТЬЕВ АМАРАНТА Amaranthus tricolor L. СОРТА EARLY SPLENDOR

An important area of systemic biology (metabolomics) is the study of the composition and properties of low-molecular metabolites of agricultural plants with different modes of nutrition. The use of metabolic technologies expands the possibilities of analyzing biochemical changes in the composition and structural modifications of metabolites occurring during the transition from autotrophic to heterotrophic nutrition. Most photosynthetic plants are capable of autotrophic nutrition, but in their lifetime, there are periods of appearance of the achlorophyllic organs which receive nutritients from the organic substances stored earlier. Thus, among Amaranthus tricolor L. plants there are varieties with leaves which differ from each other in the way of nutrition. For example, Early Splendor variety plants form brightly colored red heterotrophic leaves along with green photosynthesis leaf blades at the end of the vegetative phase. The comparative study of the low-molecular metabolites composition in these leaves is important for understanding the relationship between heterotrophic and autotrophic nutrition in the whole plant. In this paper, significant qualitative differences in metabolites composition between autotrophic and heterotrophic leaves were stated for the first time during the metabolome analysis of water and alcohol extracts of heterotrophic and autotrophic amaranth leaves of Early Splendor variety using the method of gas chromato-mass spectrometry. It was found that the low-molecular metabolites of autotrophic and heterotrophic leaves contained both non-specific metabolites common for both type of nutrition and specific metabolites characteristic for each of the ways separately. On the one hand, it indicates the close interaction between two ways of nutrition and, on the other hand, the ability to synthesize and modify the metabolites which demonstrates partial autonomy of heterotrophic leaves. The purpose of the work is to study the composition of low-molecular metabolites and to identify new biologically active metabolites antioxidants in heterotrophic and autotrophic amaranth leaves of Early Splendor variety. Experiments were carried out in 2017-2019 with amaranth plants of the Early Splendor variety at the end of flowering—the beginning of seed formation phase. The plants were grown in a film greenhouse (the Federal Research Center for Vegetable Growing). The fresh red-colored heterotrophic leaves formed at the top of the main stem and the underlying photosynthetic leaves with a fully formed leaf blade were collected for analysis. The leaves were homogenized (T18 homogenizer, IKA, Germany) and extracted for 30 min at 24 °C with either 96 % ethanol or distilled water (leaves weighing batch: extragent 1:10). The metabolites were profiled by gas chromato-mass spectrometry method (GH-MC) with a chromograph GH-MC JMS-Q1050GC (JEOL Ltd., Japan). According to the mass spectra library of the NIST-5 National Institute of Standards and Technology (USA), a total of 87 metabolites were totally identified. Heterotrophic leaves contained 19 substances in water extracts and 38 metabolites in alcohol extracts, while photosynthetic leaves contained 21 substances in the water extract and 57 metabolites in alcohol extracts. Twenty-nine identical metabolites were found in water and alcohol extracts. In heterotrophic and autotrophic amaranth leaves of Early Splendor variety squalene (C30H50), a biologically active compound with antioxidant properties was identified for the first time. Also, in heterotrophic leaves monopelargonine (monononanoin) (C15H11O7) was identified. Monopelargonine is an intermediate product of flavonoid o-glycosylation, is referred to phenolic compounds and possesses high antioxidant activity. Metabolites have been identified that are present in both autotrophic and heterotrophic amaranth leaves, which suggests a close interaction of the two types of nutrition during the appearance, growth and development of heterotrophic leaves. At the same time, photosynthesizing leaves serve as donors of key metabolites for heterotrophic leaves, while the latter are not only acceptors, but also can synthesize and modify metabolites necessary for cell formation. Due to revealed rich composition of carbohydrates, essential amino acids, lipids and organic acids, the photosynthesizing leaf biomass is a source of antioxidants and biologically active substances. It should be stressed that not all metabolites were identified. Nevertheless, the set of metabolites that we identified in the photosynthetic leaves allows us to suggest these substances to be key and sufficient compounds for the construction and functioning of cells and tissues in heterotrophic leaves.

THE METABOLITES OF AUTOTROPHIC AND HETEROTROPHIC LEAVES OF Amaranthus tricolor L. EARLY SPLENDOR VARIETY

An important area of systemic biology (metabolomics) is the study of the composition and properties of low-molecular metabolites of agricultural plants with different modes of nutrition. The use of metabolic technologies expands the possibilities of analyzing biochemical changes in the composition and structural modifications of metabolites occurring during the transition from autotrophic to heterotrophic nutrition. Most photosynthetic plants are capable of autotrophic nutrition, but in their lifetime, there are periods of appearance of the achlorophyllic organs which receive nutritients from the organic substances stored earlier. Thus, among Amaranthus tricolor L. plants there are varieties with leaves which differ from each other in the way of nutrition. For example, Early Splendor variety plants form brightly colored red heterotrophic leaves along with green photosynthesis leaf blades at the end of the vegetative phase. The comparative study of the low-molecular metabolites composition in these leaves is important for understanding the relationship between heterotrophic and autotrophic nutrition in the whole plant. In this paper, significant qualitative differences in metabolites composition between autotrophic and heterotrophic leaves were stated for the first time during the metabolome analysis of water and alcohol extracts of heterotrophic and autotrophic amaranth leaves of Early Splendor variety using the method of gas chromato-mass spectrometry. It was found that the low-molecular metabolites of autotrophic and heterotrophic leaves contained both non-specific metabolites common for both type of nutrition and specific metabolites characteristic for each of the ways separately. On the one hand, it indicates the close interaction between two ways of nutrition and, on the other hand, the ability to synthesize and modify the metabolites which demonstrates partial autonomy of heterotrophic leaves. The purpose of the work is to study the composition of low-molecular metabolites and to identify new biologically active metabolites antioxidants in heterotrophic and autotrophic amaranth leaves of Early Splendor variety. Experiments were carried out in 2017-2019 with amaranth plants of the Early Splendor variety at the end of flowering—the beginning of seed formation phase. The plants were grown in a film greenhouse (the Federal Research Center for Vegetable Growing). The fresh red-colored heterotrophic leaves formed at the top of the main stem and the underlying photosynthetic leaves with a fully formed leaf blade were collected for analysis. The leaves were homogenized (T18 homogenizer, IKA, Germany) and extracted for 30 min at 24 °C with either 96 % ethanol or distilled water (leaves weighing batch: extragent 1:10). The metabolites were profiled by gas chromato-mass spectrometry method (GH-MC) with a chromograph GH-MC JMS-Q1050GC (JEOL Ltd., Japan). According to the mass spectra library of the NIST-5 National Institute of Standards and Technology (USA), a total of 87 metabolites were totally identified. Heterotrophic leaves contained 19 substances in water extracts and 38 metabolites in alcohol extracts, while photosynthetic leaves contained 21 substances in the water extract and 57 metabolites in alcohol extracts. Twenty-nine identical metabolites were found in water and alcohol extracts. In heterotrophic and autotrophic amaranth leaves of Early Splendor variety squalene (C30H50), a biologically active compound with antioxidant properties was identified for the first time. Also, in heterotrophic leaves monopelargonine (monononanoin) (C15H11O7) was identified. Monopelargonine is an intermediate product of flavonoid o-glycosylation, is referred to phenolic compounds and possesses high antioxidant activity. Metabolites have been identified that are present in both autotrophic and heterotrophic amaranth leaves, which suggests a close interaction of the two types of nutrition during the appearance, growth and development of heterotrophic leaves. At the same time, photosynthesizing leaves serve as donors of key metabolites for heterotrophic leaves, while the latter are not only acceptors, but also can synthesize and modify metabolites necessary for cell formation. Due to revealed rich composition of carbohydrates, essential amino acids, lipids and organic acids, the photosynthesizing leaf biomass is a source of antioxidants and biologically active substances. It should be stressed that not all metabolites were identified. Nevertheless, the set of metabolites that we identified in the photosynthetic leaves allows us to suggest these substances to be key and sufficient compounds for the construction and functioning of cells and tissues in heterotrophic leaves.

Biochemical Studies Reveal Remarkable Influence of Bioremediation Treatments on Health Status of Crude Oil Polluted Soil and Oxidative Stress in Selected Plants

Oil spillage is a challenging global problem which requires urgent search for effective clean-up strategies to conserve the ecosystem. In this study, effects of crude oil pollution and bioremediation treatments on soil health and plant growth were investigated. Agricultural soil was polluted with crude oil ranging from 5.0 to 25.0 mL per kg soil. Three food crops, maize (Zea mays), soybean (Glycine max) and amaranth (Amaranthus cruentus) were planted and grown in three groups; Group I comprised plants on polluted soils without any treatment. Group II were plants on polluted soils exposed to bioremediation treatments using biostimulation and bioaugmentation methods. Group III comprised plants on clean soil which served as control. Experiments were carried out in triplicates. Soil enzyme activities and physicochemical parameters were determined using standard assay and evaluation procedures. Growth parameters, proximate composition and oxidative stress indicators of maize, soybean and amaranth plants were monitored over 120 d experimental period. Results indicated significant inhibition (p &lt 0.05) of activity of soil enzymes (dehydrogenase, β-glucosidase, acid phosphatase, arylsulphatase, amidase and protease) by crude oil pollution. The trend was significantly reversed in bioremediated soils with significant enhancement of enzyme activity. Height of plant and number of leaves significantly decreased (p &lt 0.05) with increasing concentration of crude oil polluted soil. Improvement in plant growth parameters was recorded in soils bioremediated with inorganic and organic fertilizers. Levels of oxidative stress indicators (superoxide dismutase, catalase and peroxidase) and malondialdehyde from stem of plants grown on bioremediated soils significantly reduced compared with polluted soil. GC-MS analysis revealed more significant level of crude oil degradation in soil bioremediated with inorganic fertilizer (NPK). Results established the efficacy of bioremediation treatments in alleviating toxicity of crude oil pollution in agricultural soils and revealed biostimulation using NPK and cow dung (organic fertilizer) as a more effective strategy.

Characterization of the Phenolic Compounds in Different Plant Parts of Amaranthus cruentus Grown under Cultivated Conditions.

Phenolic compounds that are present in amaranth crops have gained a lot of interest from researchers due to their health benefits potential. Therefore, the aim of this study was to investigate phenolic compounds present in different plant parts of Amaranthus cruentus using liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry. Moreover, data were analyzed by one-way analysis of variance of the statistical analysis software, whereas commercial statistical package version 4.02 was used for principal component analysis. A total of 21 phenolic compounds were detected and eight were not identified. Caffeoylsaccharic acid isomer, coumaoryl saccharic acid, tryptophan, feruloyl-d-saccharic acid isomer a, b, and c, caffeoyl isocitrate, quercetin 3-O-rhamnosyl-rhamnosyl-glucoside, feruloyl isocitrate, hyperoside, kaempferol rutinoside, and alkaloid compounds were mostly detected in tender and mature leaves. Generally, rutin content was higher (p < 0.05) in most vegetative parts of the amaranth plant, thus, late maturity leaves, tender leaves, and mature leaves, respectively. Lower quantities of rutin were observed in tender grains, flowers, and mature grains. It can be concluded that amaranth contains phenolic compounds, predominantly in the vegetative parts, which makes it to be a promising source of phenolic compounds beneficial to human health.

An Ecological and Economical Assessment of Integrated Amaranth (Amaranthus hybridus) and Nile Tilapia (Oreochromis niloticus) Farming in Dar es Salaam, Tanzania

Organic wastes can be recycled in an ecologically sound way in fishponds by applying integrated agriculture and aquaculture systems (IAA). This kind of waste recycling can help to protect the environment from pollution and improve fishpond yields. Additionally, IAA provides an opportunity for diversification of the output from two or more existing subsystems leading to higher overall farm economic returns. This study explored the potential application of amaranth wastes (AW) as a dietary ingredient for tilapia in a tilapia-amaranths integrated system (ITA). An experimental diet (AD) contained 10% (based on the control diet, CD) inclusion of AW collected from a nearby vegetable market. The experiments included triplicate treatments with; (i) fish fed on AD, where the pond water was used for irrigating the amaranth plants (IAA-fish), and (ii) fish fed on CD, where no pond water was used for irrigating the amaranth plants (non-IAA fish). 90 days after fish stocking, eighteen 4 m2 amaranth plots were prepared and treated with (i) tap water without fertilization (control amaranths), (ii) water from IAA-fish pond and organically fertilized (IAA amaranths), and (iii) tap water and inorganically fertilized (non-IAA amaranths). The use of AW improved the fish feed conversion ratio. The overall net income from ITA was 3.2, 2.3, 2.6, and 1.8 higher than from non-IAA amaranths, IAA-amaranths, non-IAA fish, and IAA fish sub-systems respectively.

Assessment of physiological and biochemical responses of Amaranthus retroflexus seedlings to the accumulation of heavy metals with regards to phytoremediation potential

The aim of this research was to assess, under laboratory conditions, how the accumulation of four heavy metals (HMs) (lead (Pb), copper (Cu), nickel (Ni), and zinc (Zn)), prepared as aqueous solutions from 1 μM to 1 mM, affected biochemical and physiological parameters of Amaranthus retroflexus seedlings. Seedlings showed considerably high resistance to all investigated HMs and no significant oxidative stress in leaves. After chronic exposure to high doses of any of the HMs, seedlings remained viable, but with slightly slower axial growth. We propose the use of biochemical indices (lipid peroxidation (LPO) intensity; level of total peroxides) as criteria to assess the adaptive potential of amaranth plants to HMs. These indices had very high correlation coefficients (r) with the accumulation of HMs in A. retroflexus roots, stems and leaves: 0.86–0.89 for malone dialdehyde (MDA) content for Ni and Zn, and 0.79–0.94 for total peroxides (for Cu, Pb, and maximum in Ni). At 1 mM of any HM, seedlings accumulated Pb and Ni at levels of HM-hyperaccumulating species. If soil is contaminated (in terms of maximum permissible concentration, MPC) by Pb (8.2 ± 2.2 MPC) or Ni (3.5 ± 1.0 MPC) (equivalent to 1 mM of the HM in solution), A. retroflexus is a strong candidate for the phytoremediation of Pb- and Ni-contaminated soils.

A natural post-emergence herbicide based on essential oil encapsulation by cross-linked biopolymers: characterization and herbicidal activity.

This work describes efforts to encapsulate savory (Satureja hortensis L.) essential oil (EO) with different natural polymers (i.e., Arabic gum/gelatin (AGG), apple pectin (AP), gelatin (G)) and, as a separate set of experiments, with bio cross-linkers (i.e., citric acid and transglutaminase enzyme). The phytotoxic activity of encapsulated savory EO on tomato (Lycopersicon esculentum Mill.) and amaranth weed (Amaranthus retroflexus L.) was investigated. The micro-capsules were evaluated in terms of size, polydispersity, stability, encapsulation efficiency, morphology, and release properties. The Korsmeyer-Peppas model operated when EO was being released from the micro-capsules. Carvacrol (52.5%) and γ-terpinene (30.2%) comprised the main constituents of the savory EO. Based on the results, encapsulating the EO with cross-linked biopolymers increased the stability and herbicidal activity of EO, as compared to simple EO emulsions. Maximum toxicity injuries (MTI) were caused by encapsulations of apple pectin, cross-linked with APe enzyme (15ml/L) on both plant species. MTI were observed 2days after using the micro-encapsulated herbicides (MCHs). However, the injury caused by MCHs on tomato was not significant. The lowest values of fresh weight (2.80g), chlorophyll a (0.194mg/g Fw), and total chlorophyll content (0.219mg/g Fw) of amaranth occurred in response to APe (15ml/L). Moreover, using AP(e) (10ml/L) caused the lowest values of starch (0.444mg/g Fw) and flavonoid contents (4.18mg Cat/g Fw) in amaranth which measured as 59% and 90% reductions, respectively, in comparison with the control. The highest values of MDA (0.0109nmol/g Fw) and H2O2 (0.0432μmol/g Fw) were observed in amaranth plants treated with AP(e) (10ml/L). In summary, cross-linked apple pectin can perform well in slow release delivery systems of agrochemicals. It can be recommended for use in the production of commercial, EO-based natural herbicides.

Effect of sonic bloom frequency on the growth of red amaranth (Alternanthera amoena Voss)

Red amaranth (Alternanthera amoena Voss) is able to be used not only as food plants but also as herbal plants. Due to a high nutrient content of red amaranth, the demand of this plant is continue to increase. Even though this plant has high demand, its productivity is relatively low. The Sonic-bloom was experimented to be applied on the red amaranth cultivation to improve the productivity. The purpose of this research is to determine the effect of various frequencies and duration of sonic-bloom exposure on the growth of the red amaranth plant (Alternanthera amoena Voss). The frequencies were set at two levels i.e. 3000-5000Hz and 7000-9000 Hz with the exposure duration were 15, 30, 45, 60 and 75 minutes respectively. The results showed that the frequency and duration of exposure have a significant influence on the cultivation parameters of red amaranth plants. Frequency treatment of 3000-5000 Hz and 7000-9000 Hz produced plants with 25.93 cm and 18.83 cm of height, 13 strands of leaves, 42 cm and 30.6 cm of plants length, 2841.01 μm2 and 3688.51 μm2 of stomata area, and 14.84 gr and 7.58 gr of wet plant weight respectively. These results were significantly different compared to the control (without sonic bloom treatment) that have 8.53 cm of height, 7-13 strands of leaves, 14.87 cm of plants length, 972.98 μm2 of stomata area, and 0.55 gr of wet weight. The best treatment in this study is the frequency of 3000-5000 Hz with exposure duration of 75 minutes, concluding that Sonic Bloom technology is able to improve the productivity of red amaranth plants.

Suitability of urban waste land use in relation to heavy metal and micronutrient influence on soil and green amaranth production in Southeast Nigeria

An assessment of the impact of long term (&gt;20 years) MSW disposal on soil properties and their suitability for crop productivity was carried out in Anambra and Enugu States of southeast Nigeria. Four dumpsites were selected (two in each state) and, 12 soil auger samples (2 sampling points at 3 depths and 2 repeated measures) each were collected at incremental depth intervals of 0-20, 20-30, and 30-40cm were collected at the dump sites and adjacent non-dumpsites situated 100 meters away from the dumpsites; The auger samples were used for the determination of Fe, B, Pb and Zn content of the soil. Forty Amaranthus spinosus biomass samples were collected from both dump and non-dumpsites in the four locations and also assayed for Fe, B, Pb, and Zn content. Results showed that the mean values of Fe concentration in the dumpsites are between 4.48 – 11.57 mg kg-1 whereas B ranged from 1.19 – 6.73 mg kg-1; Pb ranged from 0.36 – 2.19 mg kg-1 and Zn averaged from 17.2 – 54.0 mg kg-1. The values of these elements were higher than those of the corresponding non-dump sites by between 6-100 %. Pb and Zn with values of 2.0 and 0.06 mg kg-1 respectively in the amaranth plants in the dumpsite soils were higher than the permissive limits for heavy metals in vegetables. Despite the toxicity variance of the elements in the dumpsites and non-dumpsite soils and vegetables, the calculated hazard quotient (ecological risks) values of these elements were less than unity (Q.H.Q &lt; 1), suggesting that harmful effects are not likely to occur in the study areas. Public awareness creation of the dangers of plant cultivation in the unmanaged dumpsite, including health implication of heavy metal pollution and entry into the food chain as well as controlling sources of municipal wastes with appropriate legislations are recommended.

Effect of Zeolite on Nitrogen Use Efficiency and Physiological and Biomass Traits of Amaranth (Amaranthus hypochondriacus) Under Water-Deficit Stress Conditions

In the present study, the interactive effect of irrigation and nitrogen (N) on biomass and physiological characteristics of amaranth and the influence of zeolite in this interaction were investigated. A 2-year field experiment was conducted as split-plot factorial in a randomized complete block design in three replicates. The main factor consisted of different levels of deficit irrigation (DI) such as irrigation after 40 (DI1), 60 (DI2), and 75% (DI3) depletion of soil available water. The subplots derived from a combination of different factors including nitrogen rates (zero (N0), 80 (N1), 160 (N2), and 240 (N3) kg urea ha−1) and zeolite levels (zero (Z0) and 10 (Z1) ton ha−1). Reduction of soil moisture resulted in a decrease in the amount of chlorophylls, carotenoids, protein, maximum quantum yield of photosystem II (Fv/Fm ratio), and biomass of amaranth. In contrast, it resulted in the increase of antioxidant enzyme activity, soluble carbohydrates, and proline. However, nitrogen application led to an increase in the contents of chlorophyll, carotenoids, protein, antioxidant enzyme activity, Fv/Fm ratio, and biomass of amaranth and a decrease in the soluble carbohydrates and proline. Zeolite treatment by increasing the content of chlorophylls (16%), carotenoids (19%), protein (25%), Fv/Fm ratio (11%) as well as enchantment of soluble carbohydrate content and antioxidant enzyme activity and by decreasing the proline content (40%) moderated the adverse consequences of water-deficit stress and improved biomass of amaranth. In general, the use of zeolite along with the lowest rate of nitrogen fertilizer (80 kg urea ha−1) reduced the harmful effects of the oxidative stress caused by water scarcity and improved the growth conditions for the plant and thus produced maximum biomass of amaranth plant under moderate and severe deficit irrigations.

Effects of Cowpea-Amaranth Intercropping and Fertiliser Application on Soil Phosphatase Activities, Available Soil Phosphorus, and Crop Growth Response

Low available soil phosphorus (P) is associated with its immobility, which renders it unavailable for plant uptake. In addition, farmers normally apply inorganic fertilisers to legumes to activate soil-bound phosphorus using root exudates. Sufficient soil mineral nutrition is key to sustainable crop production, and hence food and nutritional security. The aim of this study was to quantify the acid and alkaline phosphatase activity as an indicator of P supply and availability under varying levels of nitrogen, phosphorus and potassium (NPK) fertilization and different cropping systems. An intercropping (cowpea and amaranth) and fertiliser (control, 25%, 50%, and 100% of the recommended NPK levels) field trial was laid out in a 2 × 4 factorial treatment structure in a completely randomized design (CRD) with four replications. There was higher acid and alkaline phosphatase activity in the rhizosphere of cowpea and amaranth grown as sole crops compared to those from intercropping. The cowpea and amaranth plants grown without fertiliser or 25% NPK had the highest rhizospheric phosphatase activity, while 100% NPK application exhibited the least. The markedly higher phosphatase activity from the low fertiliser application treatments indicates the possible stimulation of microbial activity to supplement P demands for the crops. The study revealed that the application of lower rates inorganic fertilisers in a legume intercrop stimulates the activity of the phosphatase enzymes, which can subsequently liberate soil-bound phosphorus. Plant tissue phosphorus concentration of cowpea and amaranth plants increased proportionately to the increase in fertiliser application up to 50% of the recommended NPK level. The land equivalent ratio (LER) was greater than 1, indicating that it is more beneficial to intercrop cowpea and amaranth as opposed to growing them as sole crops. Overall, the application of NPK fertilizer to amounts of up to 50%, based on the results of this study, appear to be better than 100% in terms of biomass accumulation and phosphate activity.

Identification of microRNAs involved in betalain metabolism in the green and red sectors of amaranth leaves based on Illumina sequencing data

ABSTRACT Amaranth plants are rich in betalains. Additionally, the molecular structure and metabolic pathway of betalains are different in amaranth than in beet. To date, only a few studies have examined the regulatory roles of microRNAs (miRNAs) in betalain biosynthesis in plants. Thus, we constructed small RNA libraries for the red and green sectors of amaranth leaves to identify miRNAs associated with betalain biosynthesis. We identified 239 miRNAs including 198 known and 41 novel miRNAs. 493 target genes for the 239 miRNAs were detected in an amaranth transcriptome database. The validation of the expression of 20 miRNAs and nine target genes in a quantitative real-time polymerase chain reaction assay revealed the miRNAs and target genes that were differentially expressed in the two leaf sectors. The miRNAs involved in betalain metabolism in amaranth plants were identified by Illumina sequencing platform. The data presented herein may provide insights into the regulation molecular mechanisms for betalain biosynthesis in amaranth and other plant species.

Physical and chemical analysis and biochemical composition of amaranth introduced in Dagestan

Amaranth leaves are of high nutritional value, containing various metabolites, monoand disaccharides, photosynthetic pigments, unsaturated acids, phenolcarboxylic acids with high antioxidant activity. Vegetable amaranth is grown in different soil and climatic conditions all over the world. The article describes the results of physicochemical analysis of composition of amaranth plant introduced in southern Dagestan. The results of determining biochemical composition of vitamins, organic acids, antioxidants, betacyanin - amaranthin, chlorophyll, carotenoids and chlorogenic acid in the leaves of the introduced amaranth are presented. It has been shown that amaranth culture can be an important source of vitamins and valuable biologically active substances for both humans and animals. Based on the results obtained on amaranth introduction, it can be noted that cultivation of amaranth has great prospects in Southern Dagestan, as a mass crop.