132 research outputs found
The first initiative of DNA barcoding of ornamental plants from Egypt and potential applications in horticulture industry
Abstract: DNA barcoding relies on short and standardized gene regions to identify species. The agricultural and horticultural applications of barcoding such as for marketplace regulation and copyright protection remain poorly explored. This study examines the effectiveness of the standard plant barcode markers (matK and rbcL) for the identification of plant species in private and public nurseries in northern Egypt. These two markers were sequenced from 225 specimens of 161 species and 62 plant families of horticultural importance. The sequence recovery was similar for rbcL (96.4%) and matK (84%), but the number of specimens assigned correctly to the respective genera and species was lower for rbcL (75% and 29%) than matK (85% and 40%). The combination of rbcL and matK brought the number of correct generic and species assignments to 83.4% and 40%, respectively. Individually, the efficiency of both markers varied among different plant families; for example, all palm specimens (Arecaceae) were correctly assigned to species while only one individual of Asteraceae was correctly assigned to species. Further, barcodes reliably assigned ornamental horticultural and medicinal plants correctly to genus while they showed a lower or no success in assigning these plants to species and cultivars. For future, we recommend the combination of a complementary barcode (e.g. ITS or trnH-psbA) with rbcL + matK to increase the performance of taxa identification. By aiding species identification of horticultural crops and ornamental palms, the analysis of the barcode regions will have large impact on horticultural industry
Diversity of active constituents in Cichorium endivia and Cynara cornigera extracts
The present study attempts to explore the phytochemical constituents of different extracts from Cynara cornigera and Cichorium endivia plant materials. The two species studied are native in Egypt. Five different solvents, viz., aqueous, methylene chloride, petroleum ether, ethyl acetate, and n-butanol were used. Phytochemical analysis revealed the presence of phenols, flavonoids, sterols (stigmasterol and beta-sitosterol), terpenes (α-amyrin, ursolic and oleanolic acid), and hydrocarbons (n-alkane), the latter found in low amount. The ethyl acetate and water extracts of C. cornigera root showed lower mass fractions of phenolic compounds ranged from 20 to 81 g/100 g, and higher amounts in ethyl acetate extract of the inflorescences and butanol extract of the root where values ranged from 195 to 399 g/100 g. The β-sitosterol and stigmasterol were present in all plant extracts. Oleanolic and ursolic acids were detected in roots, leaves and inflorescences of C. cornigera and in C. endivia shoot. The ethyl acetate extracts from C. cornigera leaf and inflorescence attained higher chemical diversity than the other extracts. Alternatively, sterols and triterpenes were the major constituents. The high chemical diversity of active constituents justifies the future potential use of the two species at commercial level
Seaweed Extracts Enhance Salam Turfgrass Performance during Prolonged Irrigation Intervals and Saline Shock
The negative effects of the ongoing climate change include unusual prolonged droughts and increased salinity pressures on the agricultural lands. Consequently, crops are facing unprecedented environmental pressure, and this calls for more research toward controlling such major stresses. The current study investigates the effects of seaweed extract sprays of Ascophyllum nodosum (5 and 7 mL·L−1; 6 day intervals) on Paspalum vaginatum Salam' during prolonged irrigation intervals (2 and 6 day) and saline growing conditions (1 and 49.7 dS·m−1) for 6 weeks in containers under greenhouse conditions. Control plants showed reduced turf quality, photochemical efficiency, root length and dry weight, total non-structural carbohydrates, and K and Ca compositions. Seaweed extracts increased turf quality, leaf photochemical efficiency, root length and dry weight, total non-structural carbohydrates, K, Ca, and proline in treated plants during prolonged irrigation intervals as well as saline shock conditions. There were also increases in the antioxidant defensive mechanisms such as catalase (CAT), superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities and non-enzymatic antioxidants as well as reduced lipid peroxidation. The application of SWE at 7 mL·L−1 showed higher performance in treated plants during prolonged irrigation intervals as well as saline conditions. Our findings imply that several mechanisms including drought tolerance, osmotic adjustment and antioxidant defense system may interact to enhance the performance of plants in the face of environmental stress following SWE treatments
Biogenic Synthesis, Characterization, and In Vitro Biological Evaluation of Silver Nanoparticles Using Cleome brachycarpa
The therapeutical attributes of silver nanoparticles (Ag-NPs) in both conditions (in vitro and in vivo) have been investigated using different plants. This study focused on the green chemistry approach that was employed to optimize the synthesis of silver nanoparticles (AgNPs) using Cleome brachycarpa aqueous extract as a reducing and stabilizing agent. The characterization of obtained CB-AgNPs was undertaken using UV-visible spectroscopy, Atomic-force microscopy (AFM), Fourier-Transform Infrared Spectroscopy (FTIR), scanning electron microscopy (SEM), and Energy-Dispersive X-ray (EDX) analysis. Results suggest that CB-AgNPs synthesized via stirring produced small-sized particles with more even distribution. The synthesized silver nanoparticles were spherical with a 20 to 80 nm size range. In vitro studies were used to analyze antioxidant, antidiabetic, and cytotoxic potential under different conditions. The results also indicated that CB-AgNPs may have significant potential as an antidiabetic in low concentrations, but also exhibited potential antioxidant activity at different concentrations. Moreover, the anticancer activity against the breast cell line (MCF-7) with IC50 reached up to 18 μg/mL. These results suggest that green synthesized silver nanoparticles provide a promising phytomedicine for the management of diabetes and cancer therapeutics
Mulberry based zinc nano-particles mitigate salinity induced toxic effects and improve the grain yield and zinc bio-fortification of wheat by improving antioxidant activities, photosynthetic performance, and accumulation of osmolytes and hormones
Salinity stress (SS) is a challenging abiotic stress that limits crop growth and productivity. Sustainable and cost effective methods are needed to improve crop production and decrease the deleterious impacts of SS. Zinc (Zn) nanoparticles (NPs) have emerged as an important approach to regulating plant tolerance against SS. However, the mechanisms of SS tolerance mediated by Zn-NPs are not fully explained. Thus, this study was performed to explore the role of Zn-NPs (seed priming and foliar spray) in reducing the deleterious impacts of SS on wheat plants. The study comprised different SS levels: control, 6 and 12 dS m−1, and different Zn-NPs treatments: control, seed priming (40 ppm), foliar spray (20 ppm), and their combination. Salinity stress markedly reduced plant growth, biomass, and grain yield. This was associated with enhanced electrolyte leakage (EL), malondialdehyde (MDA),
hydrogen peroxide (H2O2), sodium (Na), chloride (Cl) accumulation, reduced photosynthetic pigments, relative water contents (RWC), photosyntetic rate (Pn), transpiration rate (Tr), stomata conductance (Gs), water use efficiency (WUE), free amino acids (FAA), total soluble protein (TSP), indole acetic acid (IAA), gibberellic acid (GA), and nutrients (Ca, Mg, K, N, and P). However, the application of Zn-NPs significantly improved the yield of the wheat crop, which was associated with reduced abscisic acid (ABA), MDA, H2O2 concentration, and EL, owing to improved antioxidant activities, and an increase in RWC, Pn, Tr, WUE, and the accumulation of osmoregulating compounds (proline, soluble sugars, TSP, and FAA) and hormones (GA and IAA). Furthermore, Zn-NPs contrasted the salinity-induced uptake of toxic ions (Na and Cl) and increased the uptake of Ca, K, Mg, N, and P. Additionally, Zn-NPs application substantially increased the wheat grain Zn bio-fortification. Our results support previous findings on the role of Zn-NPs in wheat growth, yield, and grain Zn bio-fortification, demonstrating that beneficial effects are obtained under normal as well as adverse conditions, thanks to improved physiological activity and the accumulation of useful compounds. This sets the premise for general use of Zn-NPs in wheat, to which aim more experimental evidence is intensively being sought. Further studies are needed at the genomic, transcriptomic, proteomic, and metabolomic level to better acknowledge the mechanisms of general physiological enhancement observed with Zn-NPs application
Synthesis, Spectroscopic Characterization, DFT and Molecular Dynamics of Quinoline-based Peptoids
Peptoids mimic the functions of peptides which have a side chain appended to amidic nitrogen instead of α carbon. This structural change in their backbone gives them increased resistance from proteolysis, improved biostability, greater immunogenicity, and better bioavailability. Therefore, they are specifically designed for various biological activities, including antibacterial, antifungal, antioxidant, antifouling, and anticancer properties. The aim of the research is the one-pot synthesis of quinoline-based peptoids 5(a-b) via Ugi-4CR by the reaction of 1R-(-)-myrtenal 1, benzylamine 2, quinoline-based carboxylic acids 3(a-b), and cyclohexyl isocyanide 4. These peptoids were characterized by FT-IR, 1H NMR, 13C NMR, and HR ESI-MS. In computational studies, the spectral results of 5(a-b) were compared with the calculated spectral values computed at B3LYP/6-311G (d,p) level. TD-DFT method was used to predict electron excitation of 5(a-b) and the contribution of orbitals. The electronic transition of peptoids from charge distribution was computed using natural bond order (NBO) analysis. NPA and MEP analysis was calculated to predict charge distribution in 5(a-b). The FMOs analysis was executed to calculate the global reactivity descriptor to predict the reactivity and stability of peptoids. DFT analysis showed that 5b was slightly more reactive than 5a due to extended conjugation. The biological activities were also predicted using an in silico approach that involved molecular docking and molecular dynamic (MD) simulations. The antiulcer, antibacterial, and antifungal activities were predicted based on ligand–protein binding interactions, binding energy calculations, and dissociation constants. 5(a-b) were evaluated in-vitro for anticholinesterase activity, and they showed 71% inhibition. The umbrella sampling was performed to probe ligand–protein binding
Bioactivities of Traditional Medicinal Plants in Alexandria
In traditional folklore, medicinal herbs play a vital role in the prevention and treatment of microbial diseases. In the present study, the phenolic profiles of the medicinal plants Asparagus aethiopicus L., Citrullus colocynthis L., Senna alexandrina L., Kalanchoe delagoensis L., Gasteria pillansii L., Cymbopogon citratus, Brassica juncea, and Curcuma longa L. were determined by high-performance liquid chromatography with a diode-array detector method. The results revealed rich sources of important compounds such as robinin in the fruits and leaves of A. aethiopicus; caffeic acid in the tubers of A. aethiopicus and quercitrin in the leaves of G. pillansii. Further, relatively high antioxidant, antibacterial, and antifungal activities were observed in C. colocynthis fruit coat, S. alexandrina pods, and A. aethiopicus leaves, respectively. The relatively higher the bioactivities of plants extracts associated with the phenols in these plants, in particular, the more abundant the phenols. Therefore, it was concluded that the fruit coat of C. colocynthis, pods of S. alexandrina, and leaves of A. aethiopicus might be excellent sources of natural products. These plant extracts also have a wide spectrum of antimicrobial activities that could be used in the pharmaceutical industries and to control diseases
Silicon nanoparticles and indole butyric acid positively regulate the growth performance of Freesia refracta by ameliorating oxidative stress under chromium toxicity
Chromium (Cr) toxicity hampers ornamental crops’ growth and post-harvest quality, especially in cut flower plants. Nano-enabled approaches have been developing with phenomenal potential towards improving floricultural crop production under heavy metal-stressed conditions. The current pot experiment aims to explore the ameliorative impact of silicon nanoparticles (Si-NPs; 10 mM) and indole butyric acid (IBA; 20 mM) against Cr stress (0.8 mM) in Freesia refracta. The results showed that Cr stress significantly reduced morphological traits, decreased roots-stems biomass, abridged chlorophyll (14.7%) and carotenoid contents (27.2%), limited gas exchange attributes (intercellular CO2 concentration (Ci) 24.8%, stomatal conductance (gs) 19.3% and photosynthetic rate (A) 28.8%), condensed proline (39.2%) and total protein (40%) contents and reduced vase life (15.3%) of freesia plants by increasing oxidative stress. Contrarily, antioxidant enzyme activities, MDA and H2O2 levels, and Cr concentrations in plant parts were remarkably enhanced in Cr-stressed plants than in the control. However, foliar supplementation of Si-NPs + IBA (combined form) to Cr-stressed plants increased defense mechanism and tolerance as revealed by improved vegetative and reproductive traits, increased biomass, photosynthetic pigments (chlorophyll 30.3%, carotenoid 57.2%) and gaseous exchange attributes (Ci 33.3%, gs 25.6%, A 31.1%), proline (54.5%), total protein (55.1%), and vase life (34.9%) of metal contaminated plants. Similarly, the improvement in the activities of peroxidase, catalase, and superoxide dismutase was recorded by 30.8%, 52.4%, and 60.8%, respectively, compared with Cr-stressed plants. Meanwhile, MDA (54.3%), H2O2 (32.7%) contents, and Cr levels in roots (43.3), in stems (44%), in leaves (52.8%), and in flowers (78.5%), were remarkably reduced due to combine application of Si-NPs + IBA as compared with Cr-stressed nontreated freesia plants. Thus, the hypothesis that the synergistic application of Si-NPs + IBA will be an effective approach in ameliorating Cr stress is authenticated from the results of this experiment. Furthermore, the study will be significant since it will demonstrate how Si-NPs and IBA can work synergistically to combat Cr toxicity, and even when added separately, they can improve growth characteristics both under stressed and un-stressed conditions
Accumulation of phytotoxic metals and metalloids in vegetable continuum subjected to different irrigation streams: a threat towards nutritional security
The urban agro-ecosystem in developing countries plays a major role in uplifting the socioeconomic status of their inhabitants by confronting the challenges of improving food security and eradicating hunger. Food security and safety has become a serious global concern owing to accumulation of phytotoxic metals and metalloids in different food commodities subjected to different contaminated irrigation sources. The current study was undertaken to assess the concentrations of heavy metals and metalloid in ridge gourd (Luffa cylindrica L.), its planting soil medium and irrigation water sources used for crop production to determine the health risk. The results showed that the mean concentrations of different metals and metalloids in ground water samples i.e. Ni (0.14 mg L-1), Fe (1.29 mg L-1), Cu (0.10 mg L-1), Pb (0.55 mg L-1), As (0.10 mg L-1), Cr (2.38 mg L-1) and Cd (0.05 mg L-1) were over the permissible limits. Soil samples irrigated with ground water showed that concentrations of Cd (23.67 mg kg-1), Cr (26.66 mg kg-1) and As (45.97 mg kg-1) were above the permissible limits. Similarly, vegetable samples irrigated with ground water had a higher level of Cd (0.33 mg kg-1) than their prescribed safe limits. The bio-concentration factor ranged from 0.00 to 8.21 for all irrigation sources. The target hazard quotients (THQ) for Zn, Fe, and Cr were higher than the threshold value when ridge gourd was consumed, indicating a health concern. Similarly, hazard index values were 5.05, 28, 27, and 1.01, from groundwater, canal water, and sewage water, respectively. Target Cancer Risk (TCR) exposed Ni, Cr, Cd and As in canal water were sources of high cancer risk and Pb showed moderate cancer risk for the local community. These findings suggest that human intake of ridge gourd vegetable from the studied area may pose health hazards. Hence, frequent monitoring of different irrigation streams used in urban and semi-urban agriculture is strongly recommended to manage higher concentrations of phytotoxic metals and metalloids in crop produce and their associated health risks for humans.
Phage combination alleviates bacterial leaf blight of rice (Oryza sativa L.)
Rice bacterial leaf blight (BLB) is the most destructive bacterial diseases caused by Xanthomonas oryzae pv. oryzae (Xoo). Phages have been proposed as a green and efficient strategy to kill bacterial pathogens in crops, however, the mechanism of action of phages in the control of phyllosphere bacterial diseases remain unclear. Here, the glasshouse pot experiment results showed that phage combination could reduce the disease index by up to 64.3%. High-throughput sequencing technology was used to analyze the characteristics of phyllosphere microbiome changes and the results showed that phage combinations restored the impact of pathogen invasion on phyllosphere communities to a certain extent, and increased the diversity of bacterial communities. In addition, the phage combination reduced the relative abundance of epiphytic and endophytic Xoo by 58.9% and 33.9%, respectively. In particular, Sphingomonas and Stenotrophomonas were more abundant. According to structural equation modeling, phage combination directly and indirectly affected the disease index by affecting pathogen Xoo biomass and phage resistance. In summary, phage combination could better decrease the disease index. These findings provide new insights into phage biological control of phyllosphere bacterial diseases, theoretical data support, and new ideas for agricultural green prevention and control of phyllosphere diseases
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