Membrane Stability Index Research Articles

Silicon elevated cadmium tolerance in wheat (Triticum aestivum L.) by endorsing nutrients uptake and antioxidative defense mechanisms in the leaves

Numerous abiotic stressors including heavy metal stresses, specifically cadmium (Cd) stress in agricultural bio-system hinder the plant adequate growth. The present study was aimed to reveal the protective role of silicon (Si) application with two levels and to recognize the optimum level of Si for wheat plants grown hydroponically under three different levels of Cd toxicities. In methodology, we used nine treatments with three levels of Si (0, 1, and 3 mmol L−1; Na2SiO3) against three levels of Cd (0, 50, 200 μmol L−1; CdCl2) with three biological replicates. The results of our study demonstrated that Si incorporation with the advantage of 3 mmol L−1 in cultured media with Cd50 and Cd200 demolished the toxic effects of Cd on the leaves of wheat plants by increasing plant dry biomass by 88% and 262%, leaf area by 48% and 57%, total chlorophyll contents by 120% and 74%, catalase (CAT) activity by 92% and 110%, superoxide dismutase (SOD) activity by 62% and 78%, peroxidase (POD) activity by 66% and 40%, ascorbic acid (AsA) contents by 33% and 34%, glutathione (GHS) contents by 39% and 30% and reduced MDA contents by 56% and 50%, H2O2 contents by 61% and 66%, and EL contents by 56% and 47% as parallel to Cd corresponding levels. In addition, Si incorporation with the advantage of 3 mmol L−1 significantly increased relative water contents (RWC) to maintain the cell turgor pressure and protect the plant from wilting and cells flaccid and enhanced membrane stability index (MSI) to protect the plant from logging under damaging effects of Cd toxicities. Based on the present findings, Si can be considered a quasi-essential element that enhanced wheat tolerance against Cd toxicity by limiting uptake, accumulation, and translocation of Cd and through regulating antioxidative defense mechanisms.

Silver nanoparticles elicited physiological, biochemical, and antioxidant modifications in rice plants to control Aspergillus flavus

Abstract This study was carried out to analyze the effects of biogenic silver nanoparticles (AgNPs) on physiological, biochemical, and enzymatic attributes of rice plants against Aspergillus flavus. The plant-based AgNPs were synthesized by using the aqueous extract of Moringa oleifera leaves. The characterization of AgNPs was accomplished through UV-visible spectrophotometry, SEM, and energy-dispersive X-ray (EDX) analysis, which confirmed that the nanoparticles are crystalline and are less than 100 nm in size. The exogenous applications of different concentrations of AgNPs (25, 50, 75, and 100 mg/L) on rice plants in field experiments were used to control the proliferation of A. flavus. The effects of biosynthesized AgNPs were evaluated for physiological (relative water content, membrane stability index, and chlorophyll content), nonenzymatic metabolites (total phenolic, total flavonoid, proline, soluble sugar, and protein contents), and enzymatic metabolites (superoxide dismutase, peroxidase, and catalase) in rice plants under biotic stress, and 50 mg/L concentration of AgNPs was found to be effective to elicit biochemical modifications to reduce biotic stress. The 50 mg/L concentration of AgNPs was also effective in controlling the proliferation of fungal pathogen. The applications of AgNPs reduced the biotic stress by decreasing the production level of osmolytes, enzymatic, and nonenzymatic compounds but significantly increased the protein content.

Physio-Biochemical and Yield Response of Chickpea Genotypes under Salinity and High Temperature Stress

A pot experiment was carried out with six chickpea genotypes viz. KPG-59, IPC-2013-74 and NDG-15-6 (tolerant group); and KWR-108, BG-3075 and BG-3076 (susceptible group) to study the responses of these genotypes under salinity stress (4.20 dSm-1) with normal sowing, high temperature (HT) stress with late sowing and their combination (saline soil + late sowing), and compared with control (non-stress) condition based on several physio-biochemical traits such as malondialdehyde content (MDA), membrane stability index (MSI), relative water content (RWC) and proline in leaf at reproductive stage; and seed yield after harvesting. Both salinity and HT individually and in combination significantly affected the traits studied. Among the parameters, MDA increased under stress treatments over control, while MSI and RWC decreased for the same. However, combined stress exhibited hypo-additive effects for these parameters which might be due to developed cross-tolerance while facing salinity and HT stress in sequence. Increase in proline content under stress over control is an indication of osmotic adjustment in response to stress. These results might be good criteria in development of genotypes with improved response in terms of physio-biochemical traits and yield.

The effect of magnetized seawater on physiological and biochemical properties of different rice cultivars

Abstract. Sutiyanti E, Rachmawati D. 2021. The effect of magnetized seawater on physiological and biochemical properties of different rice cultivars. Biodiversitas 22: 3083-3091. Seawater is an alternative source to overcome the reduced availability of freshwater in agricultural practices. However, seawater cannot be used directly because it has high salinity that causes various disturbances in plant growth and development. Magnetic field treatment can be used for seawater desalination. The objective of this study was to analyze the potential of magnetized seawater for agricultural irrigation by observing the effect of magnetized seawater on physiological and biochemical properties of different rice cultivars. This research was conducted in a Completely Randomized Design (CRD) with 3 research factors, which were 2 rice cultivars ('IR 64' and 'Inpari 35'), 2 levels of salinity (0 and 10 dS m-1), and 4 types of magnetic treatment (0 untreated with magnetic device, 1, 2 and 3 cycles treated with magnetic device). Variables including plant growth (plant height, fresh weight and dry weight), physiological characters (chlorophyll content, carotenoid content, membrane stability index, relative water content, proline content) and biochemical properties (superoxide dismutase, malondialdehyde, H2O2 and anthocyanin content) were observed. Magnetized seawater 3 cycles enhanced growth, physiology and biochemical parameters of ‘IR 64’ and ‘Inpari 35’ in 0 and 10 dS m-1 level salinity with decreasing level salinity of water to minimize effect of salinity. The effect of magnetized seawater treatment is more visible to increase the growth of ‘IR 64' rice plants.

Physiological and Biochemical Mechanisms of Exogenously Applied Selenium for Alleviating Destructive Impacts Induced by Salinity Stress in Bread Wheat

Salinity is a major abiotic stress that poses great obstacles to wheat production, especially in arid regions. The application of exogenous substances can enhance plant salt tolerance and increase its productivity under salinity stress. This work aimed to assess the mechanisms of selenium (Se) at different concentrations (2, 4 and 8 μM SeCl2) to mitigate hazardous impacts of salt toxicity at physiological, biochemical and agronomic levels in bread wheat. The results displayed that Se foliar application increased chlorophyll content, net photosynthetic rate, transpiration rate, stomatal conductance, relative water content, membrane stability index, excised leaf water retention, proline, total soluble sugars, Ca content, K content, antioxidant enzyme activities and non-enzymatic antioxidant compounds compared to untreated plants. On the other hand, Se application decreased the content of Na, hydrogen peroxide and superoxide contents. Accordingly, our findings recommend exogenous Se application (in particular 8 μM) to alleviate the deleterious effects induced by salinity stress and improve wheat yield attributes through enhancing antioxidant defense systems and photosynthetic capacity.

Effect of Acridine Orange in Promoting Growth and Physiological Characteristics of Fragaria Ananassa Duch Under Salinity Stress in Vitro

This experimental were conducted out at plant tissue culture lab., Center of Desert studies to test the effect of four concentrations of Acridine Orange viz., 0, 10, 50 and 100mM L−1 under four levels of salinity viz., 0, 30, 60 and 90 mM NaCl L−1 on some phenological traits including: leaves number, branches number, plant length and fresh weight. Membrane stability index and electrolytic leakage also were in vitro measured. The experiment was factorial and arranged in a complete randomized design (CRD) with five replicates. Results revealed that 50 mML−1 of Acridine orange gave highest leaves number of 14.67 leaves explant−1, branches number of 3.75 branches explants−1, plant length of 1.48cm and fresh weight of 0.71g. whereas, 10 mM L−1 membrane stability index of 76.63. Furthermore, 30 mML−1 possesses highest leaves number of 11.75 leaves explants−1, branches number of 2.83 branch explant−1, plant length of 1.29cm and fresh weight of 0.58g. The highest level of salinity (90 mM) gave highest of electrolyte of 69.07.It could concluded that 50 m mol l−1 of acridine orange was the best concentration to promote growth of strawberry in vitro. Moreover, Plantlets were more tolerant to 30 m mol L−1 of Nacl in vitro.

Selenium Modulates Antioxidant Activity, Osmoprotectants, and Photosynthetic Efficiency of Onion under Saline Soil Conditions

Selenium (Se) has been recently reported to play a crucial role in ameliorating the negative impact of abiotic stress, including salinity, on several plant species. Two field experiments (2016/17 and 2017/18) were carried out to investigate the possible effect of exogenous Se application at two levels (25, 50 mg L−1) on growth, bulb yield, physio-biochemical attributes, and antioxidant activities of onion grown under saline (5.25 dS m−1) soil condition. Se (25 or 50 mg L−1) foliar application enhanced growth characteristics, as well as membrane stability index (MSI) and relative water content (RWC) as a result of the osmotic adjustment by accumulating more osmoprotectants and enhancing the activity of antioxidants defense system, thus improving photosynthetic efficiency and bulb yield. Proline, glycine betaine, choline, and total soluble sugars content were higher in leaves and bulbs of Se-treated plants under salt stress. Se (25 or 50 mg L−1) significantly increased the activities of enzymatic (ascorbate peroxidase, superoxide dismutase, and catalase) and non-enzymatic (ascorbic acid and glutathione) antioxidants in both leaves and bulbs of salt-stressed onion. Se application at 25–50 mg L−1 may find, in the future, a potential application as anti-abiotic stresses for improving plant growth and productivity under saline soil condition.

Amelioration of short-term drought stress during different growth stages in Brassica juncea by rhizobacteria mediated maintenance of ROS homeostasis.

In the present investigation, the role of rhizobacteria in alleviating the deleterious effects of drought on mustard was assessed. The plants were exposed to short-term water shortages, during the vegetative and reproductive growth stages. Drought stress in both stages had a negative effect on growth, physiological, and biochemical parameters of mustard. Both the root and shoot biomass were significantly reduced in plants exposed to drought, but rhizobacterial inoculation resulted in better plant biomass than uninoculated plants. The ameliorative effects of inoculation were also indicated by improved relative water content, membrane stability index, total chlorophyll content, and photosynthetic parameters. Similarly, inoculation resulted in enhanced activity of antioxidative enzymes superoxide dismutase (SOD), ascorbate peroxidase, and catalase in both stages of growth which possibly increased stress tolerance by maintaining reactive oxygen species (ROS) homeostasis. There was a significant reduction in the accumulation of H2 O2 , proline and total soluble sugar in rhizobacteria treated plants under drought, suggesting that the treated plants did not encounter much stress and could maintain better plant health than uninoculated plants. Expression analysis of the BjP5CSB and BjFeSOD genes was conducted during both the growth stages. Expression of the BjP5CSB gene was significantly down-regulated in inoculated plants under drought, while BjFeSOD gene transcript levels were upregulated. The vegetative stage was more responsive to rhizobacterial inoculations than the reproductive stage under drought. Principal component analysis indicated a differential response by the two growth stages to inoculation. Hence, results indicate that these rhizobacteria reduce the negative impacts of drought in mustard by maintaining ROS homeostasis.

Responses of bimetallic Ag/ZnO alloy nanoparticles and urea on morphological and physiological attributes of wheat.

Wheat (Triticum aestivum L.) is the most important staple food crop globally. According to economic survey 2018‐19, agriculture sector of Pakistan grew by 0.85%, with wheat accounting for 8.9% of agriculture and 1.6% of GDP, and its production fell short of the target by 4.9%. Wheat requires beneficial ties to improve its efficiency with the help of modern technology. Nanotechnology modifies conventional agricultural practices as these are stimulating agents for plant growth. Green bimetallic Ag/ZnO alloy nanoparticles (NPs) synthesised from salts reduced by Moringa oleifera and characterised by UV‐visible spectroscopy, scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy are studied herein. Different concentrations of urea and Ag/ZnO alloy NPs were applied exogenously to wheat plants (Pakistan‐13 and Galaxy13). A significant effect of 100 mg/L urea and 75 ppm Ag/ZnO alloy NPs was observed on the morphology of wheat, with a maximum increase of 58% plant length, 85% leaf area, 89% plant fresh weight and 76% plant dried weight. In physiological parameters, relative water content and membrane stability index have shown maximum increases of 39% and 77%, while chlorophyll a, b, and total chlorophyll content (TCC) showed maximum increases of 92%, 71%, and 84% respectively. Evidence of the morpho‐physiological responses of urea and green synthesised alloy NPs on wheat varieties are reported on.

Cadmium stress alleviation potential of Bruguiera cylindrica (L.) Blume enhances in combination with NaCl

A hydroponic experiment in NaCl tolerant mangrove, Bruguiera cylindrica plantlets was done to investigate the interactive effects of CdCl2+NaCl as well as the individual effects of CdCl2. CdCl2 alone results in enhanced level of cell membrane lipid peroxidation, damaging normal structure, and function of the membrane and there by leading to reduction of membrane stability index and thus severely promoting the electrolyte leakage than the combined treatment of CdCl2+NaCl. Antioxidants greatly contribute to cope with the stress by scavenging ROS and were more prominent in individual stress than combined stress. B. cylindrica can be categorized as a highly tolerant mangrove species with a Tolerance Index (TI) of above 60% toward CdCl2+NaCl (TI is 70 and 75% in leaf and root). But TI was only 63 and 67% in leaf and root, respectively, on exposure to CdCl2 alone indicating that this plant is less tolerant to Cd alone. The existence of B. cylindrica depends on the heavy metals being introduced into the mangrove ecosystem and imparts a combination stress along with NaCl. In this regard, B. cylindrica survives up to 0.20 mM CdCl2 along with NaCl. Thus, the high NaCl tolerance mechanisms in this mangrove species could be equally efficient in imparting tolerance toward high concentration of Cd along with NaCl and exhibits phytostabilization in polluted coastal wetlands.

Gold nanoparticles affect the cryopreservation efficiency of in vitro-derived shoot tips of bleeding heart

The popularity of nanoparticles (NPs) is continuously increasing. To date, however, there has been little research on the application of NPs in plant cryopreservation, i.e. storage of tissues in liquid nitrogen (LN). The aim of this study is to analyze the effect and evaluate the usefulness of gold nanoparticles (AuNPs) in regard to cryobiology studies. In vitro-derived shoot tips of Lamprocapnos spectabilis ‘Valentine’ were cryopreserved with the encapsulation-vitrification protocol. Gold nanoparticles (at 10–30 ppm concentration; 13 nm in size) were added either into the preculture medium; to the protective bead matrix during encapsulation; or to the recovery medium after rewarming of samples. The control plants were produced from cryopreserved explants non-treated with nanoparticles or treated with colloid dispersion medium without NPs. A non-LN-treated standard was also considered. The influence of AuNPs on the cryopreservation efficiency was determined by evaluating the recovery rate of explants and their morphogenic response; the membrane stability index (MSI); the concentration of pigments in shoots; and the antioxidant enzymes activity. The genetic stability of the plant material was evaluated using Start Codon Targeted Polymorphism (SCoT) markers. It was found that 10 ppm of AuNPs added into the alginate bead matrix improved the recovery level of LN-derived shoot tips (70.0%) compared to the non-NPs-treated cryopreserved control (50.5%). On the other hand, the presence of nanoparticles in the recovery medium had a deleterious effect on the survival of explants. AuNPs usually had no impact on the MSI (73.9–85.9%), except for those added into the recovery medium at the concentration of 30 ppm (decline to 55.8%). All LN-derived shoots were shorter and contained less chlorophyll and carotenoids than the untreated standard. Moreover, the application of AuNPs affected the enzymatic activity in L. spectabilis. Minor genetic variation was found in 8.6% of plants if AuNPs were added either into the preculture medium (at 10 and 20 ppm) or to the alginate matrix (at 30 ppm). In conclusion, AuNPs added at a lower concentration (10 ppm) into the protective bead matrix can significantly improve the cryopreservation efficiency in L. spectabilis with no alternation in the DNA sequence.

Development and evaluation of early maturing thermo-tolerant Indian mustard (Brassica juncea L. Czern & Coss) genotypes for cultivation in semi-arid region of India

Heat stress at the seedling stage can increase mortality and has become an increasing threat for Indian mustard cultivation. Indian mustard is being predominantly grown under a rainfed ecosystem. In this context, the selection of heat tolerant genotypes may be one of the panaceas. Hence, this study was planned to evolve, evaluate and identify some of the promising early maturing heat stress tolerant from a pool of advanced breeding lines, to be used as probable donors for transferring heat tolerance. For this purpose, heat stress was imposed on 10 Indian mustard advanced breeding lines at the seedling period. The mean performance of the ten advanced breeding lines of Indian mustard with respect to morphophysiology revealed that the genotype DRMRHT-13-13-5-4 recorded earliest in maturity (117.5 days), high oil content (43.14 %) and seed yield of 3182.82 (kg/ha) which was 19.75 per cent higher seed yield over best check NPJ-112 under heat stress conditions. Similarly, the genotype DRMRHT-13-13-5-6 also recorded early in maturity (118.5 days), oil content (42.18%) and seed yield of 2964.92 (kg/ha) which was 11.55 per cent higher seed yield over the best check NPJ-112. There was a positive correlation between relative water content and membrane stability index (r=0.945) but both of these traits were negatively associated with excised-leaf water loss. Cluster survey classified 10 advanced breeding lines in five divergent groups. The tree diagram revealed abundant diversity between the Indian mustard genotypes for different characters and some magnitude of a consortium between different clusters. Based on the higher membrane stability index, water retention capacity of leaves, relative water content, minimum excised-leaf water loss and seed yield, advanced breeding lines DRMRHT-13-13-5-4 and DRMRHT-13-13-5-6 were identified as early in maturity and heat tolerant at a seedling stage which could be used in breeding programmes.

Evaluation of Oxidant and Antioxidant Systems in Drought Response of Cowpea Varieties

Plant in their natural environment are exposed to several stresses such as the drought that affect their growth and productivity. Exposure of plant to drought leads to oxidative stresses as a result of increase in ROS, however plant counteract this effect by its antioxidant system. H 2 O 2 , malondialdehyde, membrane stability index, catalase and ascorbate peroxidase activities where evaluated in leaves of two cowpea varieties drought tolerant (Dan’ila) and drought susceptible (TVU 7778) during 2 weeks water deficit and 5days recovery. The result indicates significant increase in the H 2 O 2, MDA, CAT and APX activities in both varieties during the stress period and significant decrease during recovery in drought tolerant variety compared to the drought susceptible variety. The membrane stability index decreases significantly during stress period in both varieties. Drought tolerant variety has the higher ability to counteract oxidant activity during the drought stress and recover faster than the drought susceptible variety. Keywords : Drought, antioxidant, cowpea DOI: 10.7176/JNSR/12-8-03 Publication date: April 30 th 2021

ACC deaminase containing endophytic bacteria ameliorate salt stress in Pisum sativum through reduced oxidative damage and induction of antioxidative defense systems.

Approximately 6% of the world's total land area and 20% of the irrigated land are affected by salt stress. Egypt is one such country affected by salt-stress problems. This paper focuses on the role of isolated bacteria, such as Bacillus subtilis and Pseudomonas fluorescens, in alleviating the harmful effects of salt stress. The results show that the irrigation of plants with different concentrations of saline water (0, 75, and 150 mM NaCl) leads to significantly decreased growth criteria, photosynthetic pigments (i.e., chl a, chl b, and carotenoids), and membrane stability index (MSI) values. Moreover, malondialdehyde (MDA), glutathione content, endogenous proline, the antioxidant defense system, 1-aminocyclopropane-1-carboxylic acid (ACC) content, ACC synthase (ACS), ACC oxidase (ACO), and Na+ content were significantly increased under NaCl-stress exposure. On the contrary, treatment with endophytic bacteria significantly increased the resistance of pea plants to salt stress by increasing the enzymatic antioxidant defenses (i.e., superoxide dismutase, catalase, peroxidase, and glutathione reductase), non-enzymatic antioxidant defenses (i.e., glutathione), osmolyte substances such as proline, and antioxidant enzyme gene expression. As a result, endophytic bacteria's use was significantly higher compared to control values for indole-3-acetic acid (IAA), gibberellic acid GA3, MSI, and photosynthetic pigments. The use of endophytic bacteria significantly decreased Na+ accumulation while, at the same time, promoting K+ uptake. In conclusion, the induction of endophytic bacterium-induced salt tolerance in pea plants depends primarily on the effect of endophytic bacteria on osmoregulation, the antioxidant capacity, and ion uptake adjustment by limiting the uptake of Na+ and, alternatively, increasing the accumulation of K+ in plant tissue.

Biostimulation potential of biochar for remediating the crude oil contaminated soil and plant growth.

Crude oil contamination is a serious environmental threat to soil and plants growing in it. Biochar has the potential of biostimulation for remediation of crude oil-contaminated soil. Therefore, the current research was designed to analyze the bio-stimulatory impact of biochar for remediating the crude oil contaminated soil (10%, and 15%), and growth of maize under glasshouse conditions. Biochar was produced by pyrolysis of Australian pines at 350 °C. Soil incubations were done for 20 days. The results of soil analysis showed that the crude oil degradation efficiency of biochar was 34%. The soil enzymatic activities had shown 38.5% increase in fluorescein diacetate (FDA) hydrolysis and 55.6% increase in dehydrogenase activity in soil incubated with biochar in comparison to control. The soil microbial diversity was improved to 41% in biochar treated soil with respect to untreated one, while microbial respiration rate had shown a 33.67% increase in soil incubated with biochar with respect to control under oil stress. Gas Chromatography Mass spectrometry (GC-MS) analysis had shown the high content of low molecular weight hydrocarbons (C9-C13) in the soil incubated with biochar in comparison to untreated soil. Biochar showed a significant increase in fresh and dry biomass (25%, 14.61%), leaf area (10%), total chlorophyll (11%), water potential (21.6%), osmotic potential (21%), and membrane stability index (12.7%). Moreover, biochar treatment showed a higher increase in the contents of proline (29%), total amino acids (18%), soluble sugars (30.4%), and antioxidant enzymes like superoxide dismutase (16.5%), catalase (11%), and peroxidase (12%). Overall, the results of the present study suggest the bio-stimulating potential of biochar for degradation of hydrocarbons in crude oil contaminated soil and their growth-stimulating effects on maize.

Growth, Yield and Physiological Characteristics of Maize (Zea mays L.) at Two Different Soil Moisture Regimes by Supplying Silicon and Chitosan

Water deficit is an important factor to challenge food security, particularly in arid and semi-arid climates. In present experiment, silicon (Si) and chitosan were evaluated to affect the growth, yield and physiological behavior of maize (Zea mays L.) under water deficit. A pot experiment was conducted in wire house using two soil moisture regimes i.e. 100% field capacity (FC, control) and 50% FC (water deficit), 2 mM Si, 1.0 g chitosan kg−1 soil and 2 mM Si + 1.0 g chitosan kg−1 soil, and replicated thrice. Water deficit increased malondialdehyde (MDA) while decreased membrane stability index (MSI), nutrients accumulation, chlorophyll synthesis and photosynthesis, leading to a decline in grain yield of 41.17% compared to control. Silicon or/and chitosan improved the growth, yield and physiological characteristics of maize, with highest improvement by the combined use of Si and chitosan. Integrated use of Si and chitosan improved soluble proteins by 35.84%, photosynthesis 56.57%, MSI 51.38%, relative water content 58.57%, and grain yield 44.31% compared to water deficit without Si and chitosan. Silicon or/and chitosan stimulated antioxidant enzymes activities, maximum increase of 81.47% in SOD, 55.37% POD, and 134.44% CAT, while decrease in MDA 64.31% with Si + chitosan compared to water deficit without Si and chitosan. For the set of treatments under investigation, integrated use of Si and chitosan could be an important strategy to improve the growth, yield and physiological characteristics of maize under water deficit.

Influence of tinting on physiological and keeping quality parameters of tuberose (Polianthus tuberosa) spikes

Tinting adds not only variation to flower colours but also to economy of farmers. The different food colours are being used for tinting but little is known about their action. So, the present investigation to evaluate the effect of different food colours on physiological and keeping quality parameters of tuberose (Polianthus tuberosa L.) spikes was conducted at Punjab Agricultural University during 2017-18. The tuberose spikes cv. Prajwal were tinted with food dyes, viz. Apple green, Classic blue, Orange red and Rose pink @ 1% alone and supplemented with sucrose (2%) and citric acid (300 ppm) for 1 and 2 hrs. Tinting had no adverse effect on vase life although other quality parameters, viz. change in weight, dye solution uptake, opening of floret, number of florets drop/spike and water uptake were affected. Based on number of floret drop/spike and floret opening, spikes tinted with Apple green and Classic blue dye solution supplemented with sucrose and citric acid had more acceptability than those tinted with Rose pink and Orange red. The better acceptability of Apple green and Classic blue tinted spikes was associated with more membrane stability index, total soluble protein and total soluble sugar content which decreased with senescence (at the end of vase life). Thus, tinting with Apple green and Classic blue for 1 h in supplemented solution can add colour to tuberose spikes without having any adverse effect on its post-harvest attributes.

Integrated Effects of Potassium Humate and Planting Density on Growth, Physiological Traits and Yield of Vicia faba L. Grown in Newly Reclaimed Soil

Several agronomic factors, including planting density, affect plant growth and final yield. New soil suffers from severe fertility shortage and crop productivity. Potassium humate (KH) application improves soil fertility and plant performance under new soil conditions. Therefore, this investigation was performed in two seasons of 2018/2019 and 2019/2020 to study the impact of KH application at the rate of 50 kg hectare−1 (ha−1) on growth, yield, physio-biochemical attributes, plant water status and nutrients in faba bean plants grown in newly reclaimed soil under three planting densities, i.e., D1 = 222.222 plants ha−1 (15 × 60 cm), D2 = 166.666 plants ha−1 (20 × 60 cm) and D3 = 133.333 plants ha−1 (25 × 60 cm). The results showed that KH application enhanced tissue water status by increasing the membrane stability index (MSI%) and relative water content (RWC%), while electric leakage (EL%) was reduced, alongside increased growth attributes physio-biochemical properties and nutrients. These results were positively reflected by the improved yield and its components (i.e., number of pods plant−1, 100-seed weight, seed yield plant−1 and seed yield ha−1) in favor of the medium planting density (166.666 plants ha−1). The results of the current study showed that the application of KH with the medium planting density (20 × 60 cm) was the best treatment combination to enhance the performance and productivity (2.97 ton ha−1) of faba bean plants grown under newly reclaimed soil conditions.

Putrescine-functionalized carbon quantum dot (put-CQD) nanoparticles effectively prime grapevine (Vitis vinifera cv. \u2018Sultana\u2019) against salt stress

BackgroundSalinity is an important global problem with destructive impacts on plants leading to different biochemical and metabolic changes in plants through induced oxidative stress that disturbs metabolism, growth, performance and productivity of plants. Given that putrescine (Put) and carbon quantum dots (CQDs), individually, have promising effects in different plant processes, the idea of their combination in a nano-structure “Put-CQD” lead to its synthesis to evaluate the potential exertion of synergistic effects. The current study aimed to investigate the application of newly-synthesized nanoparticles (NPs) consisting of CQDs and Put in grapevine (Vitis vinifera cv. ‘Sultana’) under salinity stress conditions. For this purpose, Put, CQDs and Put-CQD NPs at 5 and 10 mg L− 1 concentrations were applied as chemical priming agents in ‘Sultana’ grapevine 48 h prior salinity stress imposition (0 and 100 mM NaCl).ResultsSalinity significantly decreased (P ≤ 0.05) morphological parameters, photosynthetic pigments, chlorophyll fluorescence parameters and membrane stability index. In addition, salinity enhanced MDA, H2O2, proline content and antioxidant enzyme activity. Results revealed that Put-CQD NPs, particularly at 10 mg L− 1 concentration, alleviated the destructive impacts of salinity stress by improving leaf fresh and dry weights, K+ content, photosynthetic pigments, chlorophyll fluorescence and SPAD parameters, proline content, total phenolics and antioxidant enzymatic activities (CAT, APX, GP and SOD), while decreasing Na+ content, EL, MDA and H2O2 levels.ConclusionTo conclude, Put-CQD NPs represent an innovative priming treatment that could be effectively applied on grapevine to improve plant performance under salinity stress conditions.

Glycine betaine functionalized graphene oxide as a new engineering nanoparticle lessens salt stress impacts in sweet basil (Ocimum basilicum L.)

Regarding destructive impacts of salinity on different vital processes of plants, many strategies have been developed to alleviate salinity effects. Amongst, nanoparticles (NPs) application has been achieved great attention. For that point, considering positive effects of graphene oxide NPs (GO) and glycine betaine (GB) on different plant processes, GO-GB NPs were primarily synthesized to use GO as a carrier for GB. Then, GO, GB and GO-GB (each in three concentrations; 0, 50 and 100 mg L−1) were applied on sweet basil (Ocimum basilicum L.) plants under 0, 50 and 100 mM salinity stress conditions. The results demonstrated that GO-GB NPs could lessen negative effects of salinity by enhancing agronomic traits, photosynthetic pigments, chlorophyll fluorescence parameters, membrane stability index (MSI), proline, phenols, antioxidant enzymes activities and dominant constituents of essential oils and decreasing MDA and H2O2. These positive effects were more considerable at its lower dose (50 mg L−1) introducing it as the best treatment to ameliorate sweet basil performance especially essential oil compounds under salt stress. GO application at its higher dose (100 mg L−1) demonstrated toxicity by negative impacts on the measured parameters. In conclusion, the positive response of sweet basil to GO-GB NPs under non-stress and salt stress conditions cause to consider the NPs as potential novel plant growth promoting and stress protecting agent with innovative outlooks for its use in agriculture.