Integral effects of brassinosteroids and timber waste biochar enhances the drought tolerance capacity of wheat plant

Drought stress is among the major threats that affect negatively crop productivity in arid and semi-arid regions. Probably, application of some additives such as biochar and/or brassinosteroids could mitigate this stress; however, the mechanism beyond the interaction of these two applications is not well inspected. Accordingly, a greenhouse experiment was conducted on wheat (a strategic crop) grown under deficit irrigation levels (factor A) i.e., 35% of the water holding capacity (WHC) versus 75% of WHC for 35 days while considering the following additives, i.e., (1) biochar [BC, factor B, 0, 2%] and (2) the foliar application of 24-epibrassinolide [BR, factor C, 0 (control treatment, C), 1 (BR1) or 3 (BR2) mu mol)]. All treatments were replicated trice and the obtained results were statistically analyzed via the analyses of variance. Also, heat-map conceits between measured variables were calculated using the Python software. Key results indicate that drought stress led to significant reductions in all studied vegetative growth parameters (root and shoot biomasses) and photosynthetic pigments (chlorophyll a, b and total contents) while raised the levels of oxidative stress indicators. However, with the application of BC and/or BR, significance increases occurred in the growth attributes of wheat plants, its photosynthetic pigments, especially the combined additions. They also upraised the levels of enzymatic and non-enzymatic antioxidants while decreased stress indicators. Furthermore, they increased calcium (Ca), phosphorus (P) and potassium (K) content within plants. It can therefore be deduced that the integral application of BR and BC is essential to mitigate drought stress in plants.Peer reviewe

Associative effects of activated carbon biochar and arbuscular mycorrhizal fungi on wheat for reducing nickel food chain bioavailability

Heavy metal stress and less nutrient availability are some of the major concerns in agriculture. Both abiotic stresses have potential to decrease the crops productivity. On the other hand, organic fertilizers i.e., activated carbon biochar (ACB) and arbuscular mycorrhizal fungi (AMF) increase nutritional and heavy metal like Nickel (Ni) stress tolerance and provide immunity to plants for their survival in unfavorable environments. Previous studies have only looked at single applications of either ACB or AMF thus far. There is limited evidence of their synergistic effects, especially in plants growing in soil contaminated with nickel (Ni). To cover the knowledge gap of combined use of AMF inoculation (Glomus intraradices) and/or wheat straw biochar amendments on wheat growth, antioxidant activities and osmolytes concentration, present study is conducted. The use of either the AMF inoculant or the ACB alone resulted in improved wheat growth and decreased Ni uptake. Furthermore, sole AMF or ACB also reduced Ni stress effectively, allowing wheat to grow faster and reducing soil Ni transfer into plant tissue. In comparison to a control, adding ACB with AMF inoculant considerably increased fungal populations. The most significant increase in wheat growth and decrease in tissue Ni contents came from amending soil with AMF inoculant and biochar. Inducing soil alkalinization and causing Ni immobilization, as well as decreasing Ni phyto-availability, the combination treatment had a synergistic impact. These findings imply that AMF inoculation in ACB treatment could be used not only for wheat production but also for Ni-contaminated soil phyto-stabilization. (C) 2022 The Author(s). Published by Elsevier B.V.Peer reviewe

A Combined Use of Rhizobacteria and Moringa Leaf Extract Mitigates the Adverse Effects of Drought Stress in Wheat (Triticum aestivum L.)

Less nutrient availability and drought stress are some serious concerns of agriculture. Both biotic and abiotic stress factors have the potential to limit crop productivity. However, several organic extracts obtained from moringa leaves may induce immunity in plants under nutritional and drought stress for increasing their survival. Additionally, some rhizobacterial strains have the ability to enhance root growth for better nutrient and water uptake in stress conditions. To cover the knowledge gap on the interactive effects of beneficial rhizobacteria and moringa leaf extracts (MLEs), this study was conducted. The aim of this experimental study was to investigate the effectiveness of sole and combined use of rhizobacteria and MLEs against nutritional and drought stress in wheat. Nitrogen-fixing bacteria Pseudomonas aeruginosa (Pa) (10(8) CFU ml(-1)) was inoculated to wheat plants with and without foliar-applied MLEs at two different concentrations (MLE 1 = 1:15 v/v and MLE 2 = 1:30 v/v) twice at 25 and 35 days after seed sowing (50 ml per plant) after the establishment of drought stress. Results revealed that Pa + MLE 2 significantly increased fresh weight (FW), dry weight (DW), lengths of roots and shoot and photosynthetic contents of wheat. A significant enhancement in total soluble sugars, total soluble proteins, calcium, potassium, phosphate, and nitrate contents validated the efficacious effect of Pa + MLE 2 over control-treated plants. Significant decrease in sodium, proline, glycine betaine, electrolyte leakage, malondialdehyde, hydrogen peroxide, superoxide dismutase (SOD), and peroxide (POD) concentrations in wheat cultivated under drought stress conditions also represents the imperative role of Pa + MLE 2 over control. In conclusion, Pa + MLE 2 can alleviate nutritional stress and drought effects in wheat. More research in this field is required to proclaim Pa + MLE 2 as the most effective amendment against drought stress in distinct agroecological zones, different soil types, and contrasting wheat cultivars worldwide.Peer reviewe

Exogenously applied ZnO nanoparticles induced salt tolerance in potentially high yielding modern wheat (Triticum aestivum L.) cultivars

Salinity stress is one of the potential threats that adversely affect the productivity of many cereal crops worldwide. Spraying plants with nano-Zn particles may lessen effectively such negative impacts on plants; yet its mode of action is still not well explored. This study was performed to evaluate the effects of spraying nano-Zn particles with varying concentrations (0, 20, 50 and 80 mg L-1) on two wheat cultivars irrigated with saline water (EC = 6.3 dS m-1) versus a non-saline one. The key results revealed that root and shoot weights decreased significantly under salinity stress conditions, while improved considerably with nano-Zn-particles foliar application up to 50 mg nanoZn L-1; thereafter significant reductions occurred. Also, shoot and root lengths as well as plant leaf area index improved considerably owing to this foliar application. Clearly, roots and shoots weights of wheat plants sprayed with nano-Zn particles under salinity stress conditions exhibited higher values than the corresponding ones that was grown under non-saline conditions without nano-Zn-particles applications. Unexpectedly, this foliar spray led to significant reductions in plant pigments and also in enzymatic and non-enzymatic antioxidants in plants. Yet, this foliar spray enhanced formation of total soluble sugars and proline, and raised significantly Ca contents in wheat roots and shoots, and to some extent K contents. In conclusion, the foliar application of nano-Zn particles increased plant growth under salty stress conditions via two parallel processes, i.e., stimulating formation of osmolytes and stimulating nutrient uptake which may, in turn, increase plant metabolism. (c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CCPeer reviewe

In vitro cytotoxic and antioxidant activities of phenolic components of Algerian Achillea odorata leaves

In this study, methanol extract from Achillea odorata was evaluated for its phenolic contents using Folin–Ciocalteu reagent, and antioxidant activity using: 1,1-diphenyl-2-picrylhidrazyl (DPPH) radical scavenging activity, reducing activity of H2O2 and ferric reducing power assay. The total phenolic content was determined as gallic acid (GAE) equivalent. Flavonoids and flavonols contents were determined as quercetin (QE) equivalents. The cytotoxicity of the plant extract was tested against three tumor cell lines: MCF-7, Hep2 and WEHI using 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphynyl tetrazolium bromide (MTT) assay. Preliminary screening was concluded in the presence of substances with large therapeutic values. The total phenolic content confirmed the presence of total phenolics in the extract and showed strong association with antioxidant activity. An important content of flavonoids and flavonols was also detected. The results of the antioxidant activities obtained indicate that A. odorata recorded a good capacity. For the cytotoxic activity, the results showed the plant extract significantly inhibited tumor cell growth and colony formation at various concentrations

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population