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关键词： Antioxidant enzymes   Brassica oleracea   Crude oil   Dopamine   Stress   POLYCYCLIC AROMATIC-HYDROCARBONS   ZEA-MAYS L.   NITRIC-OXIDE   CONTAMINATED SOIL   OXIDATIVE STRESS   GROWTH   METABOLISM   TOLERANCE   PLANTS   OIL  

摘要： Hydrocarbon stress has become one of the most restrictive factors for crop choice and productivity in most parts of the world. Dopamine (DA) has positively influenced the metabolic, physiological and biochemical activities besides the growth of plants under numerous abiotic stress conditions. The current study was performed to analyze the potential of DA to alleviate hydrocarbon stress and improve growth of Brassica oleracea plants. Hydrocarbon stress in plants was induced by growing in 5% and 10% crude oil contaminated soil. Crude oil stressed plants exhibited reduced growth besides decreased level of photosynthetic pigments and gas exchange attributes. Moreover, oil stressed plants showed elevated level of hydrogen peroxide (H2O2), electrolyte leakage (EL), malondialdehyde (MDA) and superoxide radical (O2-). However, exogenous application of 50, 100 and 200 mu mol L-1 DA improved photosynthesis, shoot and root dry weight of B. oleracea seedlings growing in hydrocarbon amended soil. Additionally, DA100 treatments improved non-enzymatic and enzymatic antioxidants of treated seedlings. Our results demonstrate that increased gas exchange attributes, modulation of osmoregulators and improved activity of the antioxidative enzymes alleviated hydrocarbon stress in DA supplemented B. oleracea plants. Consequently, the first time observed ameliorative role of DA in hydrocarbon stress opens a new arena for application of this dynamic biomolecule for sustainable crop production. (c) 2020 Elsevier Ltd. All rights reserved.

关键词： Meal frequency   Meta-analysis   Blood glucose   Lipid   Triglyceride   Cholesterol   6 ISOCALORIC MEALS   EATING FREQUENCY   RISK-FACTORS   CALORIC RESTRICTION   FOOD GROUPS   CARDIOVASCULAR-DISEASE   PROTEIN-INTAKE   NORMAL-WEIGHT   INSULIN   GLUCOSE  

摘要： Background: Although several randomized controlled trials (RCTs) have supported the beneficial effects of higher meal frequency (MF) on cardiometabolic risk factors, the putative effects of higher MF on health remain inconclusive. This study systematically reviewed the evidence from RCTs of the effect of higher compared with lower MF on the blood lipid profile, glucose homeostasis, and adipokines. Methods: PubMed, Scopus, ISI Web of Science, and the Cochrane database were searched up to October 2020 to retrieve relevant RCTs. A DerSimonian and Laird random effects model was used to pool mean differences and 95% CI for each outcome. The quality of studies and evidence was assessed through standard methods. Results: Twenty-one RCTs (686 participants) were included in this meta-analysis. Overall results showed a significant improvement in total cholesterol [weighted mean difference (WMD) = -6.08 mg/dl; 95% CI: -10.68, -1.48; P = 0.01; I2 = 88%], and low-density cholesterol (LDL-C) (WMD = -6.82 mg/dl; 95% CI: -10.97, -1.60; P = 0.009; I2 = 85.7%), while LDL-C to high-density cholesterol ratio (LDL-C: HDL-C) increased (WMD = 0.22; 95% CI: 0.07, 0.36; P = 0.003; I2 = 0.0%) in higher MF vs. lower MF. No significant effects were found on measures of glycemic control, apolipoproteins-A1 and B, or leptin. In subgroup analyses, higher MF significantly reduced serum triglyceride (TG), and increased HDL-C, compared with lower MF in interventions > 12 weeks, and decreased serum TC and LDL-C in healthy participants. A significant reduction in LDL-C also was observed in studies where the same foods given both arms, simply divided into different feeding occasions, and in feeding studies, following higher MF compared to lower MF. Conclusion: Our meta-analysis found that higher, compared with lower MF may improve total cholesterol, and LDL-C. The intervention does not affect measures of glycemic control, apolipoproteins-A1 and B, or leptin. However, the GRADE ratings of low credibilit

关键词： Chitosan   Salicylic acid   Wheat   Source-activity   Cellular homeostasis   Reserve food remobilization   Nanoparticles   POLYPHENOL OXIDASE   STRESS   ASSAY   RESISTANCE   INDUCTION   GROWTH   MAIZE   SEED  

摘要： Sustained source-activity is imperative for vigor plant growth and yield. In present study, physio-biochemical responses of wheat plant contributing to source-activity were measured after application of salicylic acid-chitosan nanoparticles (SA-CS NPs). SA-CS NPs slowly release SA for sustained availability to plant. In seedling bioassay, as compared with salicylic acid (SA), SA-CS NPs incurred up to similar to 1.5 folds increased activities of seed reserve food remobilizing enzymes for substantial mobilization of reserve food to growing seedlings and enhanced seedling vigor index (SVI) by 1.6 folds. At booting stage, foliar application of SA-CS NPs (0.01-0.08%; w/v) enhanced the activities of superoxide dismutase (1.94 folds), catalase (1.33 folds), peroxidase (1.99 folds) and polyphenol oxidase (1.04 folds) in flag leaf. SA-CS NPs further contrived cellular homeostasis by comforting reactive oxygen species (ROS), malondialdehyde (MDA) and proline contents in flag leaf. SA-CS NPs (0.08%; w/v) significantly increased chlorophylls (a-b) contents (1.46 folds), spike length without awns, spike lets per spike and grain weight per pot as compared with SA. Study categorically explicates that slow release of SA from SA-CS NPs could exert significant effect on source-activity by maneuvering various physio-biochemical responses of wheat plant.

关键词： Abscisic acid (ABA)   Antioxidant metabolism   Bud dormancy   Carbohydrate metabolism   Dormancy release   Gibberellins (GAs)   Peroxidase (POX)   CONTAINING SUPEROXIDE-DISMUTASE   ABSCISIC-ACID   TEMPERATURE-DEPENDENCE   SEED DORMANCY   JAPANESE PEAR   FRUIT-TREES   BREAKING   EXPRESSION   GENES   ENDODORMANCY  

摘要： In this work, we studied the interplay among the levels of starch, sugars, abscisic acid (ABA) and bioactive gibberellins (GAs), and the antioxidant metabolism during bud dormancy release in a low chill peach variety. The experiments were performed in two consecutive years and two geographical areas with different annual media temperature. In the cold area, peach plants accumulated more starch and soluble sugars than in the temperate area, sorbitol and sucrose being the most abundant sugars. The enzymatic activities of the ascorbate-glutathione (ASC-GSH) cycle and the ROS-scavengers enzymes superoxide dismutase (SOD), catalase and peroxidase (POX) were measured. The increased activity of the ASC-GSH cycle enzymes and POX suggested a mild oxidative stress at endodormancy and at dormancy release periods. In this sense, the presence of H2O2-sensitive antioxidant enzymes, including Fe-SOD, Cu,Zn-SOD, POX and APX in the floral buds could trigger the oxidative signaling leading to dormancy release. Interestingly, the induction of a new POX isoenzyme occurred at dormancy release, suggesting its use as a marker for this event in low chill peach varieties. GAs levels decreased at the end of the dormancy period, whereas ABA levels showed a strong decline throughout the dormancy period, especially in buds from the cold area. As a consequence, a sharp decrease in the ABA/GAs ratio was observed, a phenomenon closely related to dormancy release. This response was more evident in the cold area. Results suggested that a decrease in ABA levels, as well as in the ABA/GAs ratio, may be necessary for the bud dormancy release in peach, at least in low chill varieties. Overall, we observed an interaction among sugars, antioxidant enzymes and plant hormones in the dormancy period. Glucose levels correlated with chill accumulation, peaking at ecodormancy and dormancy release. This response was parallel with increases in some antioxidant enzymes, the induction of a new POX isoenzyme and the

关键词： Seed drying   Oxidative stress   Germination metabolism   Lipid peroxidation   WHEAT TRITICUM-AESTIVUM   RICE ORYZA-SATIVA   STRESS TOLERANCE   L.   FERTILIZATION   GERMINATION   RESPONSES  

摘要： Faba bean (Vicia faba L.) productivity is limited by drought stress and is often associated with mineral nutrient deficiencies such as zinc (Zn). Three independent experiments were conducted to optimize Zn application and its role in tolerance against drought in faba bean. In the first experiment, faba bean seeds soaked in aerated 0.001, 0.01, 0.05, 0.1 and 0.5 M Zn solutions (osmopriming) or water (hydropriming) for 12 h were sown in Petri plates in a growth chamber. Based on the results, in the second and third experiments, faba bean seeds were subjected to osmopriming with 0.001 M Zn solution and hydropriming followed by surface drying and re-drying of seed to the original weight. In third experiment, treated faba bean seeds were planted in peat moss-filled pots maintained at 75 % water holding capacity (WHC) (well-watered) or 50 % WHC (drought stress). In the first study, seeds primed with high Zn concentration (>= 0.01 M Zn) did not germinate. Drought stress suppressed the seedling emergence, growth with enhanced oxidative stress. However, seed priming with 0.001 M Zn solution followed by surface drying ameliorated the adverse effect of drought stress by increasing the biomass production (99.8 %), leaf area (23 %), a amylase activity (85 %), soluble sugar (54.7 %), Soil Plant Analysis Development (SPAD) value (48.7 %), leaf Zn concentration (79.8 %) with reduction in leaf malondialdehyde (42.7 %) content and total antioxidant activities (35.2 %) under drought stress compared to untreated control. Conclusively, adequate Zn supply through seed priming can help in ameliorating the adverse effect of drought stress in faba bean during the early seedling growth stage.