Induction Stage Research Articles

Changes in phytohormone content and associated gene expression throughout the stages of pear (Pyrus pyrifolia Nakai) dormancy.

To elucidate the role of phytohormones during bud dormancy progression in the Japanese pear (Pyrus pyrifolia Nakai), we investigated changes in phytohormone levels of indole acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA) and trans-zeatin (tZ). Using ultra-performance liquid chromatography/mass spectrometry/mass spectrometry, we monitored phytohormone levels in the buds of field-grown and potted trees that were artificially heated to modify the timing of dormancy and flowering (spring flush) progression. We also analyzed the expression of GA- and ABA-metabolic genes during dormancy. Indole acetic acid and tZ levels were low during dormancy and increased toward the flowering stage. Gibberellic acid levels were maintained at relatively high concentrations during the dormancy induction stage, then decreased before slightly increasing prior to flowering. The low GA concentration in potted trees compared with field-grown trees indicated that GA functions in regulating tree vigor. Abscisic acid levels increased from the dormancy induction stage, peaked near endodormancy release and steadily decreased before increasing again before the flowering stage. The ABA peak levels did not always coincide with endodormancy release, but peak height correlated with flowering uniformity, suggesting that a decline in ABA concentration was not necessary for resumption of growth but the abundance of ABA might be associated with dormancy depth. From monitoring the expression of genes related to GA and ABA metabolism, we inferred that phytohormone metabolism changed significantly during dormancy, even though the levels of bioactive molecules were consistently low. Phytohormones regulate dormancy progression not only upon the reception of internal signals but also upon sensing ambient conditions.

ANESTHETIC EFFICACY OF CLOVE OIL AND 2-PHENOXYETHANOL ON DOCTOR FISH, <i>Garra rufa</i> (HECKEL, 1843)

This study aimed to determine the anesthetic efficacy of clove oil and 2-phenoxyethanol on doctor fish (Garra rufa) at two different water temperatures. Experimental fish (1.2 ± 0.2 g mean weight) were subjected to 25, 50, 75 and 100 μL L-1 clove oil and 100, 200, 300, 400 and 500 μL L-1 2-phenoxyethanol concentrations at water temperature of 15 and 25 °C, and the induction and recovery times were investigated. Results showed that induction and recovery times in doctor fish were significantly affected by clove oil and 2-phenoxyethanol concentrations as well as water temperature. The interaction of anesthetic concentration and water temperature on all induction stage time was significant in clove oil. Between the anesthetic concentration and temperature interaction was significant for recovery times in both anesthetic agents. The induction time decreased significantly with increasing concentration of both anesthetic agents at water temperature of 15 and 25 °C. The lowest effective concentrations that produced induction within 3 min and recovery within 5 min were 50-75 μL L-1 of clove oil and 300 μL L-1 of 2-phenoxyethanol in both 15 and 25 °C respectively. The results also indicated that clove oil was effective at 4-fold lower concentrationsthan 2-phenoxyethanol, but the recovery time was longer than 2-phenoxyethanol. These results suggest that clove oil and 2-phenoxyethanol were effective anesthetics and could be used as anesthetic agents in doctor fish.

Efficient and rapid in-vitro plantlet regeneration via somatic embryogenesis in ornamental bananas (Musa spp.)

A simple and efficient protocol developed for plantlet regeneration through in vitro somatic embryogenesis in three ornamental bananas. In vitro propagation, especially somatic embryogenesis has been a method of choice to obtain homogenous planting material in ornamental bananas. In the present investigation, true-to-type plants via somatic embryogenesis were achieved in three ornamental bananas viz. Musa laterita, Musa beccarii and Musa velutina using immature male flower bud as explants. The evaluation was carried out at two stages of somatic embryogenesis, induction, and maturation of somatic embryos. Embryogenic calli desiccated up to 2 h at 25 ± 1 °C resulted in higher frequencies of embryo induction and maturation compared to non-desiccated embryos. The plantlets generated were hardened, and the genetic fidelity of the plantlets was confirmed using SRAP markers. It was observed that banana plants derived via somatic embryogenesis displayed normal phenotype as that of plants grown from a single elite mother plant. In the present study, the successful establishment of plants from male flower bud was achieved in 6 to 7 months which is a relatively short duration compared to other reports involving different species of banana. The protocol developed could be useful for large-scale micropropagation studies in these commercially important ornamental bananas.

Exposure to opposing temperature extremes causes comparable effects on Cardinium density but contrasting effects on Cardinium-induced cytoplasmic incompatibility.

Terrestrial arthropods, including insects, commonly harbor maternally inherited intracellular symbionts that confer benefits to the host or manipulate host reproduction to favor infected female progeny. These symbionts may be especially vulnerable to thermal stress, potentially leading to destabilization of the symbiosis and imposing costs to the host. For example, increased temperatures can reduce the density of a common reproductive manipulator, Wolbachia, and the strength of its crossing incompatibility (cytoplasmic incompatibility, or CI) phenotype. Another manipulative symbiont, Cardinium hertigii, infects ~ 6–10% of Arthropods, and also can induce CI, but there is little homology between the molecular mechanisms of CI induced by Cardinium and Wolbachia. Here we investigated whether temperature disrupts the CI phenotype of Cardinium in a parasitic wasp host, Encarsia suzannae. We examined the effects of both warm (32°C day/ 29°C night) and cool (20°C day/ 17°C night) temperatures on Cardinium CI and found that both types of temperature stress modified aspects of this symbiosis. Warm temperatures reduced symbiont density, pupal developmental time, vertical transmission rate, and the strength of both CI modification and rescue. Cool temperatures also reduced symbiont density, however this resulted in stronger CI, likely due to cool temperatures prolonging the host pupal stage. The opposing effects of cool and warm-mediated reductions in symbiont density on the resulting CI phenotype indicates that CI strength may be independent of density in this system. Temperature stress also modified the CI phenotype only if it occurred during the pupal stage, highlighting the likely importance of this stage for CI induction in this symbiosis.

METHODS FOR CONTROL THE SELF-SUSTAINED PLASMA-BEAM DISCHARGE AT HIGH ENERGY DENSITY

Three methods for control the self-sustained plasma-beam discharge at high energy density are presented in this paper. Using a particular method, it is possible to set the location of the double layers formation in the discharge gap, as well as control its parameters at the high-current inductive discharge stage. It is shown that such methods can significantly increase the active power inputted into the discharge.

Influence of Precursors on the Induction Period and Transition Regime of Dimethyl Ether Conversion to Hydrocarbons over ZSM-5 Catalysts

ZSM-5 catalysts were subjected to step response cycles of dimethyl ether (DME) at 300 °C in a temporal analysis of product (TAP) reactor. Propylene is the major olefin and displays an S-shaped profile. A 44 min induction period occurs before primary propylene formation and is reduced upon subsequent step response cycles. The S-shaped profile was interpreted according to induction, transition-regime, and steady-state stages to investigate hydrocarbon formation from DME. The influence of precursors (carbon monoxide, hydrogen, dimethoxymethane, and 1,5-hexadiene) was studied using a novel consecutive step response methodology in the TAP reactor. The addition of dimethoxymethane, carbon monoxide, hydrogen, or 1,5-hexadiene reduces the induction period of primary olefin formation. However, while dimethoxymethane, carbon monoxide, and hydrogen accelerate the transition regime toward hydrocarbon pool formation, 1,5-hexadiene attenuates it. Heavier hydrocarbons obtained from 1,5-hexadiene compete for active sites...

Application effect of different stages of focus intervention in hemodialysis induction stage patients

Objective To investigate the effect of different stages of key intervention in hemodialysis induction. Methods A total of 80 cases of induction period patients who received hemodialysis treatment in the center from January 2014 to December 2017 were selected and divided into observation group and control group with 40 cases each according to random number table method.The observation group carried out key interventions at different stages for patients, which were divided into three stages: early induction stage, induction stage and late induction stage. A total of 7 times of comprehensive psychological intervention and health education were planned for patients and their families, and the psychological status of patients at the three stages was analyzed for targeted key interventions.The control group was randomized to receive one-time health education during dialysis treatment. Results The observation group was significantly better than the control group in terms of dialysis treatment compliance, hemodialysis-related knowledge, nursing satisfaction and incidence of complications during dialysis, with statistically significant differences (P<0.05). Conclusion The key intervention at different stages is helpful for patients to consciously adopt healthy behaviors when they are exposed to hemodialysis, improve treatment compliance, eliminate tension, anxiety and fear, reduce complications, and make a smooth transition from induction to maintenance dialysis. Key words: Induction period; Hemodialysis; Different stages; Key intervention; Application evaluation

Effect of The Ethylene Inhibitor “Agno3”, Vitamin B9 “Folic Acid” And Thiol Compound “GSH” On in Vitro Propagation of Sideritis Syriaca L. Subsp. Syriaca (Hellenic Mountain Tea of The Crete Island)

The aim of this research was to study the effect of the ethylene inhibitor “silver nitrate (AgNO3)” and vitamin B9 "folic acid" in different concentrations combined with cytokinin BA as well as the antioxidant thiol compound “L-glutathione reduced (GSH)” in different concentrations simultaneously with auxins (IBA+NAA) on micropropagation efficiency of the endemic Sideritis syriaca L. subsp. syriaca (Hellenic mountain tea of Crete/ Malotira) using shoot tip explants. The culture medium used was the MS supplemented with 30 g/l sucrose. The simultaneous application 5 ?M AgNO3 + 2.2 ?M BA promoted best the initial shoot induction stage exhibiting 4.5 shoots/ explant and 100% shoot multiplication (5 weeks). Folic acid applied at 0.25 mg/l in combination with 0.5 mg/l BA exhibited the highest shoot multiplication percentage (90%) (4 weeks). GSH at 10 ?M with 10.7 ?M NAA + 4.92 ?M IBA gave the greatest root length (13.68 mm), at 25 ?M caused a 3-fold increase in rooting (90%) and 250 ?M GSH raised by 20% shoot multiplication (80%). An 89% final survival rate of rooted microplants to ex vitro unheated greenhouse conditions was recorded within 8 weeks period during mid-late spring. Thus, the acclimatization and hardening process was successfully completed.

CLP1, a Novel Plant Homeo Domain Protein, Participates in Regulating Cellulase Gene Expression in the Filamentous Fungus Trichoderma reesei.

The stringent regulatory network of cellulase gene expression in the filamentous fungus Trichoderma reesei involves multiple transcriptional regulators. However, identification and mechanistic investigation of these regulators are still insufficient. Here, we identified a novel transcriptional regulator, CLP1, a plant homeo domain (PHD) Protein that participates in regulating T. reesei cellulase gene expression. Phylogenetic analyses demonstrated that CLP1 homologs are widely distributed in filamentous fungi including Trichoderma, Penicillium, Fusarium, Neurospora, and Aspergillus species. We demonstrated that CLP1 is a nuclear protein and lack of CLP1 significantly impaired the induced expression of cellulase genes. ChIP experiments showed CLP1 binding to the cellulase gene promoters specifically under cellulose conditions and compromised XYR1 occupancy on the same promoters in the absence of CLP1 at the early induction stage. XYR1 overexpression fully rescued the defect in cellulase production but not the defect in conidia formation in the clp1 null mutant. Further analysis showed that the PHD is required for the CLP1 appropriate subcellular localization as well as the induced cellulase gene expression and conidiation. Taken together, these data demonstrated an important role of CLP1 in the regulation of cellulase and xylanase gene expression in T. reesei.

In vitro establishment of Monstera acuminata Koch and Monstera deliciosa Liebm

In this paper we present the bases for the aseptic establishment of Monstera acuminata Koch and Monstera deliciosa Liebm (Araceae) from leaves and the induction of in vitro organogenesis of M. acuminata K. from discs of stems of young shoots. Different disinfection protocols were applied to mature leaves and young shoots, from which foliar explants of 1 cm2 of both species were extracted, and stem disks approximately 1 mm of thick in M. acuminata K. The explants were established in semi-solid media with different hormonal treatments during the stage of aseptic establishment and induction of organogenesis. Disinfection with 3 % of sodium hypochlorite (NaClO) for 20 min and 50 % Murashige y Skoog medium (1962) with PPM, led to less oxidation in the leaf explants of both species. All the explants in the two treatments belonging to M. deliciosa, grown in medium added with PPM and different disinfection protocols, survived, did not present contamination and more than 80 % maintained answer’s capacity until 49 days of culture. After 35 days of culture, with disinfection in Tween 20 + Ethanol 20% + 2.5% NaClO, and sowing of the explants in the MS medium added with 1 mg/l of BAP, 0.5 mg/l of AIA and 0.1 mg/l of ANA were indueces seven new shoots of stem disks. M. deliciosa had better ability to adapt to in vitro conditions. Advances in the establishment and induction of organogenesis in native araceas for wicker production are the basis for ex situ conservation of local populations.

Screening the Reference Genes for Quantitative Gene Expression by RT-qPCR During SE Initial Dedifferentiation in Four Gossypium hirsutum Cultivars that Have Different SE Capability.

RNA sequencing (RNA-Seq)-based gene expression analysis is applicable to a wide range of biological purposes in various species. Reverse transcription quantitative PCR (RT-qPCR) is also used to assess target gene expression utilizing stably expressed reference genes as internal control under a given set of conditions. However, investigations of the reference genes for RT-qPCR normalization in the process of somatic embryogenesis (SE) initial dedifferentiation in Gossypium hirsutum are rarely reported. In this study, on the basis of our previous transcriptome data of three different induction stages during SE initial dedifferentiation process in four G. hirsutum cultivars that have different SE capability, 15 candidate genes were selected during SE initial dedifferentiation process, and their expression stability was evaluated by geNorm, NormFinder, and BestKeeper. The results indicated that the two genes of endonuclease 4 (ENDO4) and 18S ribosomal RNA (18S rRNA) showed stable expression in the four different G. hirsutum cultivars, endowing them to be appropriate reference genes during three induction stages in the four cotton cultivars. In addition, the stability and reliability of the two reference genes of ENDO4 and 18S rRNA were further verified by comparing the expressions of auxin-responsive protein 22 (AUX22) and ethylene-responsive transcription factor 17 (ERF17) between RT-qPCR results and the RNA-seq data, which showed strong positive correlation coefficient (R2 = 0.8396–0.9984), validating again the steady expression of ENDO4 and 18S rRNA as the reliable reference genes. Our results provide effective reference genes for RT-qPCR normalization during SE process in different G. hirsutum cultivars.

Generation of functional dopaminergic neurons from human spermatogonial stem cells to rescue parkinsonian phenotypes

BackgroundRecent progress in the induced generation of dopaminergic (DA) neurons from different types of stem cells or reprogrammed somatic cells holds tremendous potential for the treatment of Parkinson’s disease (PD). However, the lack of a reliable source for cell replacement therapy remains a major limitation in the treatment of human neurological disorders. Additionally, the current protocols for in vitro differentiation or cell reprogramming to generate human DA neurons are laborious, time-consuming, and expensive, and efficient conversion of human spermatogonial stem cells (hSSCs) to functional DA neurons has not yet been achieved.MethodsPrimary hSSCs from testicular tissues of patients were exposed to an improved induction system, which consisted mainly of olfactory ensheathing cell conditioned culture medium (OECCM) and a set of defined cell-extrinsic factors and small molecules. Morphological changes were assessed, along with the expression of various DA neuron phenotypic markers (e.g., Tuj-1, TH, Nurr1, DAT) and several critical pro-DA neurogenesis effectors (e.g., EN-1, Pitx3, Foxa2, Lmx1a, Lmx1b, and OTX2). In addition, transcriptome analysis was used to further evaluate the genetic similarity between the artificially differentiated DA neurons and genuine ones. Concomitantly, the functional properties of converted DA neurons including synapse formation, dopamine release, electrophysiological activity, and neuron-specific Ca2+ signaling images were determined. Finally, hSSCs in the early stage of induction were evaluated for survival, differentiation, migration, tumorigenicity in the mouse striatum, and improvement of functional deficits in MPTP-induced PD animals.ResultsThe hSSC-derived neurons not only acquired neuronal morphological features but also expressed various phenotypic genes and protein characteristic of DA neurons and several effectors critical for pro-DA neurogenesis. Strikingly, as the period of induction was prolonged, expression of the critical molecules for DA neuron epigenetic status gradually increased while hSSC-specific markers sharply decreased. After 3 weeks of induction, the transdifferentiation efficiency reached 21%. In addition, hierarchical clustering analysis showed that the differentiated DA neurons closely resembled genuine ones. Furthermore, the hSSC-derived neurons gained sophisticated functional properties of wild-type DA neurons, and pro-induced hSSCs efficiently survived, migrated, and differentiated into DA neurons without tumorigenesis after transplantation into mouse striatum, leading to improvement of functional deficits in PD animals.ConclusionsThe results showed that, using the present improved straightforward approach, hSSCs could acquire DA neuron morphological features and functional properties and rescue parkinsonian phenotypes. Our strategy for the conversion of hSSCs into DA neurons is very efficient and thus may provide an alternative approach suitable for clinical cell therapy to treat neurodegenerative diseases including PD.

The Yes and No of the Ethylene Involvement in Abscission.

Abscission has significant implications in agriculture and several efforts have been addressed by researchers to understand its regulatory steps in both model and crop species. Among the main players in abscission, ethylene has exhibited some fascinating features, in that it was shown to be involved at different stages of abscission induction and, in some cases, with interesting roles also within the abscising organ at the very early stages of the process. This review summarizes the current knowledge about the role of ethylene both at the level of the abscission zone and within the shedding organ, pointing out the missing pieces of the very complicated puzzle of the abscission process in the different species.

Retrospective view of the early career: three landmarks in building resilience in academic administration among Israeli teacher training college principals

ABSTRACT This study provides a retrospective view by Israeli Teacher Training College (TTC) principals of their early careers, with emphasis on the induction into their first academic-administrative positions. The thematic analysis of 10 life stories reveal three landmarks which contributed to building or impeding resilience in academic administration at the induction, adaptation and consolidation stages. Whereas the first and third stages were identified with the ‘Pygmalion Effect’ and the ability to establish an effective model of leadership, the adaptation stage was seen as impeding the development of resilience. The findings are discussed in relation to the literature on resilience in different educational contexts, and examine its applicability to the organisational culture of Israeli TTCs.

Oral health in children with acute lymphoblastic leukaemia: before and after chemotherapy treatment.

Toevaluatechanges in the oral health status ofchildrenunder the age of 14years with acute lymphoblastic leukaemia (ALL) attending a cancer centre before and after chemotherapy treatment. A total of 32 children with ALL without distinction of gender were selected for study. The oral cavity of the patients was evaluated before the induction stage and 17days later. Clinical evaluation of the submandibular, submental, and cervical lymph nodes was performed. Saliva samples were collected during the early morning hours. Bacterial plaque was assessed by using the Silness and Löe plaque index (SLPI) and gingiva status was evaluated with the gingival Löe and Silness index (GLSI). The WHO toxicity oral scale was used to record the degree of oral mucositis. The resulting data were analysed with McNemar's test, t test (for related samples), and Wilcoxon test. There were statistically significant differences for palpable lymph nodes, paleness of oral mucosa, and ecchymoseis, respectively, P ≤ 0.000, P = 0.03, and P = 0.01, with thesemanifestationsdecreasing significantly after treatment. Incipientgingivitis had frequencies of 71.9% and 75% before and after treatment, respectively. The mean SLPI score declined significantly from 1.16 ± 0.52 (before treatment) to0.56 ± 0.36 (after treatment) (P < 0.000); salivary flowincreasedsignificantly from0.54 ± 0.34to 1.22 ± 1.07 after chemotherapy treatment (P < 0.00). Oral mucositiswas present in24 children (75%)witha 1-2 severitylevel. After chemotherapy treatment, there were changes in the oral conditions of children with ALL. Some manifestations decreased after treatment, whereas inothers increased.

The failure process of mortars during sulfate attack

External sulfate attacks on concrete structures may cause serious damage and it has attracted a wide range of attention from numerous researchers over the past decades. However, many studies have been concentrated on the sample which has been already destroyed. This paper investigated the entire deterioration process of mortars that were immersed in Na2SO4 solution containing 3 gSO4 2-/L and 33.8g SO4 2-/l at 20 o C up to 600 days. The study on time-varying regularity of expansion, cracks, compressive strength and mineral phases was investigated. Back scattered electron image was used to further examine the evolution of microstructures of the mortars during the attack process. The results showed that damage process of mortars can be described as induction stage, surface damage, bulk damage and then completely damage stage. Fine ettringites that were formed in restricted spaces, approximately 2-5 μm, result in surface damage. At the bulk damage stage, cracking was the main characteristic of mortar which leads to obvious expansion. In this stage, some large ettringite crystals (&amp;gt;20μm) were just deposited in the formed cracks. At the later stage, gypsum can be easily formed at interfacial transition zones as the consumption of calcium hydroxide, which mainly contributed to completely strength failure rather than expansion.

Transcriptome Characterization of Gene Profiling During Early Stage of Nitric Oxide-Induced Adventitious Rooting in Mung Bean Seedlings

Nitric oxide (NO) functions as a signaling molecule modulating diverse developmental and physiological processes in plants. NO was recently shown to strongly induce the formation of adventitious roots in plants. A transcriptome analysis was performed using RNA-Seq and qRT-PCR technologies to obtain further insights into the gene expression profile underlying NO-induced adventitious rooting. Sodium nitroprusside (SNP), a widely used NO donor, significantly up-regulated the GO terms and pathways oxidoreductase activity, wounding response, water deprivation response, microtubule-based process, cell cycle, cell wall synthesis, photosynthesis, hydrolase activity at the root induction stage, response to stress, cell wall loosening and biogenesis, ethylene signaling at the root initiation stage. In total, 2582 and 2588 differentially expressed genes (DEGs, fold change ≥ 2) were selected in plants receiving the 6- and 24-h SNP treatments, respectively. The analysis of the most highly differentially expressed genes (RPKM ≥ 10 and fold change ≥ 2) shows that NO significantly regulated the expression of genes involved in nitrogen compound response, stress response, oxidative stress response, cell wall modification, signal transduction, protein processing, secondary metabolism, metabolic processes, and transcription factors (TFs), as well as plant hormone signaling. Notably, the expression of a large number of genes encoding peroxidase (POD) isoforms was significantly differentially regulated by SNP. Furthermore, qRT-PCR results indicated that NO significantly up-regulated the expression of several genes with known functions in pathways such as auxin signaling and stress response, as well as TF genes, at the root induction and initiation stages. The evidence obtained implies that NO up-regulated the expression of genes that are involved in the key cellular processes leading to the root formation.

Mechanisms of Nucleation and Stationary States of Electrochemically Generated Nanobubbles.

Gas evolving reactions are ubiquitous in the operation of electrochemical devices. Recent studies of individual gas bubbles on nanoelectrodes have resulted in unprecedented control and insights on their formation. The experiments, however, lack the spatial resolution to elucidate the molecular pathway of nucleation of nanobubbles and their stationary size and shape. Here we use molecular simulations with an algorithm that mimics the electrochemical formation of gas, to investigate the mechanisms of nucleation of gas bubbles on nanoelectrodes, and characterize their stationary states. The simulations reproduce the experimental currents in the induction and stationary stages, and indicate that surface nanobubbles nucleate through a classical mechanism. We identify three distinct regimes for bubble nucleation, depending on the binding free energy per area of bubble to the electrode, Δγbind. If Δγbind is negative, the nucleation is heterogeneous and the nanobubble remains bound to the electrode, resulting in a low-current stationary state. For very negative Δγ, the bubble fully wets the electrode, forming a one-layer-thick micropancake that nucleates without supersaturation. On the other hand, when Δγbind > 0 the nanobubble nucleates homogeneously close to the electrode, but never attaches to it. We conclude that all surface nanobubbles must nucleate heterogeneously. The simulations reveal that the size and contact angle of stationary nanobubbles increase with the reaction driving force, although their residual current is invariant. The myriad of driven nonequilibrium stationary states with the same rate of production of gas, but distinct bubble properties, suggests that these dissipative systems have attractors that control the stationary current.

Enhanced biomass and lipid production of Neochloris oleoabundans under high light conditions by anisotropic nature of light-splitting CaCO3 crystal

The aim of this work was to study the anisotropic effect of crystalline CaCO3 nanoparticles (CN)-driven multiple refraction/scattering from the CN-coated agglomerated cells on the rate of photosynthesis and the product yield under high light conditions in the freshwater microalgae Neochloris oleoabundans. The CN-coating via biomineralization significantly improved the biomass and lipid production of N. oleoabundans during second stage of autotrophic induction by sustaining relatively high rate of photosynthesis at high irradiance using the multiple-splitting effect of the anisotropic polymorphism. The CN were successfully produced, adsorbed and grown on the external cells under conditions of mild alkalinity (pH 7.5–8.0), mild CaCl2 concentration (0.05 M) and under nitrogen starvation with strong light (400 µE m−2 s−1). Consequently, lipid content and productivity of N. oleoabundans cells cultured with 0.05 M CaCl2 increased by 18.4% and 31.5%, respectively, compared to the cells cultured with 0.05 M CaCl2 and acetazolamide to inhibit calcification.

Nitric oxide donor improves adventitious rooting in mung bean hypocotyl cuttings exposed to cadmium and osmotic stresses

Exogenous application of a nitric oxide donor, sodium nitroprusside (SNP), improved the formation and growth of adventitious roots in mung bean hypocotyl cuttings. The combined applications of SNP and CdCl2 or mannitol partially overcame the negative effects of Cd and mannitol on adventitious rooting compared with Cd or mannitol alone. SNP significantly increased the endogenous NO level and the glutathione (GSH), ascorbic acid (ASA), polyphenol, and proline (Pro) levels during the root induction and/or initiation stages. However, the malondialdehyde (MDA) levels were significantly reduced by the SNP treatment during the entire time course. To unveil the role of NO in mediating the plant response to heavy metal and osmotic stresses during adventitious rooting, SNP together with CdCl2 or mannitol was applied in the experiments. The results obtained showed that the Cd- or mannitol-induced changes in the levels of GSH, ASA, polyphenol, Pro, and MDA and the activities of ascorbate peroxidase (APX), peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), and indole-3-acetic acid oxidase (IAAO) were completely or partially reversed by SNP supplementation in the SNP + Cd/mannitol treatments, suggesting that NO mediated the redox state via the regulation of antioxidative systems to prevent membrane lipid peroxidation in response to the stresses during adventitious rooting. Furthermore, the protective effects of NO on the cellular antioxidative systems under the stresses were similar to those of IBA, implying that auxin and NO shared common pathways to respond to the stresses and leading to adventitious rooting in mung bean hypocotyl cuttings under heavy metal and osmotic stresses. NO mediates the redox state and prevents membrane lipid peroxidation during adventitious rooting in plants exposed to abiotic stresses via the regulation of antioxidant levels and antioxidative enzyme activities. NO shares common signaling pathways with auxin or acts as a downstream mediator of auxin in response to abiotic stresses during adventitious rooting.