2-chloroethylphosphonic Acid Research Articles

Using Pomegranate Peel Extract to Change the Adverse Effect of Ethephon by Enhancing its Antioxidant, Anti-inflammatory, and Anti-apoptotic Effects in Rats

Organophosphorus insecticide and growth regulator namely Ethephon (2-chloroethylphosphonic acid) are widely used as a ripening process accelerator and a cultivation duration inhibitor. Pomegranate extract (PPE) has recently been taken into consideration due to its pharmacological effects especially those associated with renal diseases. Thus, this study aims to investigate the possible protective effect of PPE against ethephon-induced nephrotoxicity in rats. In this study four groups of adult male rats were divided into control group, PPE 400 mg/kg group, Ethephon 250 mg/kg group, and finally, PPE + Ethephon group (treated with the same dose of PPE group and Ethephon group). In the current study, kidney function parameters (KIM-1, creatinine, and urea) along with oxidative stress markers, heme oxygenase-1 (HO-1) and nuclear factor erythroid 2–related factor 2 (Nrf2), glutathione (GSH) and its correlated enzymes, nitric oxide (NO), superoxide dismutase (SOD), malondialdehyde (MDA) and catalase (CAT) were estimated. Additionally, mediators of renal inflammation: interleukin 1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), nuclear factor kappa B (NF-κB) were measured. Apoptotic biomarkers (Bax, caspase 3, and Bcl2) in addition to renal histopathological data were also investigated. Results revealed that Ethephon elicited a significant increase in oxidation markers and reduced antioxidant levels, accompanied by oxidative renal tissue injury. Consequently, administration of Ethephon was reported to provoke secretion of the pro-inflammatory mediators. Moreover, histopathological results showed that deformities in the renal tissues were noticed which is attributed to Ethephon exposure. Interestingly, co-administration of PPE and Ethephon resulted in significantly ameliorated the biochemical and histopathological alterations produced by Ethephon. Current results propose the potential effect of PPE in the protection of renal tissue from Ethephon induced nephrotoxicity in rats.

Evaluation of volatile constituents, exudation of resin and occurrence of galls of Protium aracouchini (Aubl.) Marchand

Protium aracouchini (Aubl.) Marchand [sin Icica aracouchini Aubl.], which occurs in the Adolpho Ducke Forest Reserve, in the Brazilian Amazon, was evaluated for the presence of galls, for resin exudation and the composition of the essential oils from the aerial parts and the resin. The experiment to stimulate the exudation of resin from the trunk was conducted using a 2-chloroethylphosphonic acid solution. The resin produced after 40 days and the aerial parts had their essential oils extracted in a Clevenger apparatus and the volatile chemical constituents were analyzed using GC/MS. The non-oxygenated sesquiterpenes α-copaene (21.15%) and α-gurjunene (13.69%), in addition to the oxygenated sesquiterpene spathulenol (10.32%), were detected as the majority constituents of the essential oil of the leaves, and a concentration similar to that of α-gurjunene was found in the branches (13.28%). The resin essential oil showed a high concentration of hydrocarbon monoterpenes (76.49%) with a predominance of α-pinene (17.57%) and limonene (46.11%). Four gall morphotypes were found associated with this species. The present study reports for the first time information on the volatile constituents and the resinous potential of P. aracouchini, and registers the morphotypes of the galls that help in the taxonomy of the species.

Ethephon-Induced Ethylene Enhances Protein Degradation in Source Leaves, but Its High Endogenous Level Inhibits the Development of Regenerative Organs in Brassica napus.

To investigate the regulatory role of ethylene in the source-sink relationship for nitrogen remobilization, short-term effects of treatment with different concentrations (0, 25, 50, and 75 ppm) of ethephon (2-chloroethylphosphonic acid, an ethylene inducing agent) for 10 days (EXP 1) and long-term effects at 20 days (Day 30) after treatment with 100 ppm for 10 days (EXP 2) on protein degradation and amino acid transport in foliar sprayed mature leaves of Brassica napus (cv. Mosa) were determined. In EXP 1, endogenous ethylene concentration gradually increased in response to the treated ethephon concentration, leading to the upregulation of senescence-associated gene 12 (SAG12) expression and downregulation of chlorophyll a/b-binding protein (CAB) expression. Further, the increase in ethylene concentration caused a reduction in protein, Rubisco, and amino acid contents in the mature leaves. However, the activity of protease and expression of amino acid transporter (AAP6), an amino acid transport gene, were not significantly affected or slightly suppressed between the treatments with 50 and 75 ppm. In EXP 2, the enhanced ethylene level reduced photosynthetic pigments, leading to an inhibition of flower development without any pod development. A significant increase in protease activity, confirmed using in-gel staining of protease, was also observed in the ethephon-treated mature leaves. Ethephon application enhanced the expression of four amino acid transporter genes (AAP1, AAP2, AAP4, and AAP6) and the phloem loading of amino acids. Significant correlations between ethylene level, induced by ethephon application, and the descriptive parameters of protein degradation and amino acid transport were revealed. These results indicated that an increase in ethylene upregulated nitrogen remobilization in the mature leaves (source), which was accompanied by an increase in proteolytic activity and amino acid transport, but had no benefit to pod (sink) development.

A new approach to suppress methane emissions from rice cropping systems using ethephon

Rice is the main staple food for more than half of the world's population. Yet, rice cultivation is subjected to criticism because of its important role in methane (CH4) emissions. Although several agronomic practices such as controlled irrigation and conservation tillage have been widely adopted to mitigate CH4 emissions from rice cultivation, the benefits gained by these practices are highly dependent on site-specific soil and climate conditions, and often offset by yield reduction. The use of plant growth regulating compounds having the potential to increase the crop yield and mitigate CH4 emissions may be an innovative approach to sustainable agriculture. Ethylene (C2H4), a plant growth regulator is known to have a strong inhibitory effect on methanogenesis. However, due to gaseous form and low water solubility, C2H4 has not been used to suppress methanogenesis in paddy fields. To develop C2H4 as a prospective soil amendment for reducing methane (CH4) emissions, ethephon (2-Chloroethylphosphonic acid), a precursor of C2H4 was tested. We found that ethephon reduced CH4 formation by 43%, similar to other well known methanogenic inhibitors (2-Bromoethanesulfonate, 2-Chlomoethanesulfonate, 2-Mercaptoethanesulfonate). However, ethephon rapidly hydrolyzed to C2H4 and methanogenic activity recuperated completely after C2H4 removal. To slow down the release of C2H4, ethephon was mixed with bio-degradable polymers such as cellulose acetate and applied to paddy soils. We found that compared with the control, the C2H4 release of ethephon slowed down to 90 days, and the CH4 emissions were reduced by 90%. The application of ethephon at lower concentrations did not significantly alter bacterial communities, their relative abundance, and the abundance of methanotrophs, but it significantly reduced archaeal communities and the relative abundance and expression level of methanogens in paddy soils. Results suggest that cellulose acetate-mixed ethephon has great promise to suppress CH4 emissions in rice paddies while ensuring sustainable yields.

Ethephon-Induced Ethylene Enhances Starch Degradation and Sucrose Transport with an Interactive Abscisic Acid-Mediated Manner in Mature Leaves of Oilseed rape (Brassica napus L.).

The leaf senescence process is characterized by the degradation of macromolecules in mature leaves and the remobilization of degradation products via phloem transport. The phytohormone ethylene mediates leaf senescence. This study aimed to investigate the ethephon-induced ethylene effects on starch degradation and sucrose remobilization through their interactive regulation with other hormones. Ethephon (2-chloroethylphosphonic acid) was used as an ethylene-generating agent. Endogenous hormonal status, carbohydrate compounds, starch degradation-related gene expression, sucrose transporter gene expression, and phloem sucrose loading were compared between the ethephon-treated plants and controls. Foliar ethephon spray enhanced the endogenous ethylene concentration and accelerated leaf senescence, as evidenced by reduced chlorophyll content and enhanced expression of the senescence-related gene SAG12. Ethephon-enhanced ethylene prominently enhanced the endogenous abscisic acid (ABA) level. accompanied with upregulation of ABA synthesis gene 9-cis-epoxycarotenoid dioxygenase (NCED3), ABA receptor gene pyrabactin resistance 1 (PYR1), and ABA signaling genes sucrose non-fermenting 1 (Snf1)-related protein kinase 2 (SnRK2), ABA-responsive element binding 2 (AREB2), and basic-helix-loop-helix (bHLH) transcription factor (MYC2).) Ethephon treatment decreased starch content by enhancing expression of the starch degradation-related genes α-amylase 3 (AMY3) and β-amylase 1 (BAM1), resulting in an increase in sucrose content in phloem exudates with enhanced expression of sucrose transporters, SUT1, SUT4, and SWEET11. These results suggest that a synergistic interaction between ethylene and ABA might account for sucrose accumulation, mainly due to starch degradation in mature leaves and sucrose phloem loading in the ethephon-induced senescent leaves.

Exogenous ethylene reduces growth via alterations in central metabolism and cell wall composition in tomato (Solanum lycopersicum)

Ethylene is a gaseous hormone with a well-established role in the regulation of plant growth and development. However, its role in the modulation of carbon assimilation and central metabolism remains unclear. Here, we investigated the morphophysiological and biochemical responses of tomato plants (Solanum lycopersicum) following the application of ethylene in the form of ethephon (CEPA - 2-chloroethylphosphonic acid), forcing the classical triple response phenotype. CEPA-treated plants were characterized by growth inhibition, as revealed by significant reductions in both shoot and root dry weights, coupled with a reduced number of leaves and lower specific leaf area. Growth inhibition was associated with a reduction in carbon assimilation due to both lower photosynthesis rates and stomatal conductance, coupled with impairments in carbohydrate turnover. Furthermore, exogenous ethylene led to the accumulation of cell wall compounds (i.e., cellulose and lignin) and phenolics, indicating that exposure to exogenous ethylene also led to changes in specialized metabolism. Collectively, our findings demonstrate that exogenous ethylene disrupts plant growth and leaf structure by affecting both central and specialized metabolism, especially that involved in carbohydrate turnover and cell wall biosynthesis, ultimately leading to metabolic responses that mimic stress situations.

Ethylene reduces glucose sensitivity and reverses photosynthetic repression through optimization of glutathione production in salt-stressed wheat (Triticum aestivum L.)

Ethylene plays a crucial role throughout the life cycle of plants under optimal and stressful environments. The present study reports the involvement of exogenously sourced ethylene (as ethephon; 2-chloroethyl phosphonic acid) in the protection of the photosynthetic activity from glucose (Glu) sensitivity through its influence on the antioxidant system for adaptation of wheat (Triticum aestivum L.) plants under salt stress. Ten-day-old plants were subjected to control and 100 mM NaCl and treated with 200 µl L−1 ethephon on foliage at 20 days after seed sowing individually or in combination with 6% Glu. Plants receiving ethylene exhibited higher growth and photosynthesis through reduced Glu sensitivity in the presence of salt stress. Moreover, ethylene-induced reduced glutathione (GSH) production resulted in increased psbA and psbB expression to protect PSII activity and photosynthesis under salt stress. The use of buthionine sulfoximine (BSO), GSH biosynthesis inhibitor, substantiated the involvement of ethylene-induced GSH in the reversal of Glu-mediated photosynthetic repression in salt-stressed plants. It was suggested that ethylene increased the utilization of Glu under salt stress through its influence on photosynthetic potential and sink strength and reduced the Glu-mediated repression of photosynthesis.

Ethylene-Cytokinin Interaction Determines Early Defense Response of Wheat against Stagonospora nodorum Berk.

Ethylene, salicylic acid (SA), and jasmonic acid are the key phytohormones involved in plant immunity, and other plant hormones have been demonstrated to interact with them. The classic phytohormone cytokinins are important participants of plant defense signaling. Crosstalk between ethylene and cytokinins has not been sufficiently studied as an aspect of plant immunity and is addressed in the present research. We compared expression of the genes responsible for hormonal metabolism and signaling in wheat cultivars differing in resistance to Stagonospora nodorum in response to their infection with fungal isolates, whose virulence depends on the presence of the necrotrophic effector SnTox3. Furthermore, we studied the action of the exogenous cytokinins, ethephon (2-chloroethylphosphonic acid, ethylene-releasing agent) and 1-methylcyclopropene (1-MCP, inhibitor of ethylene action) on infected plants. Wheat susceptibility was shown to develop due to suppression of reactive oxygen species production and decreased content of active cytokinins brought about by SnTox3-mediated activation of the ethylene signaling pathway. SnTox3 decreased cytokinin content most quickly by its activated glucosylation in an ethylene-dependent manner and, furthermore, by oxidative degradation and inhibition of biosynthesis in ethylene-dependent and ethylene-independent manners. Exogenous zeatin application enhanced wheat resistance against S. nodorum through inhibition of the ethylene signaling pathway and upregulation of SA-dependent genes. Thus, ethylene inhibited triggering of SA-dependent resistance mechanism, at least in part, by suppression of the cytokinin signaling pathway.

Ethylene and Sulfur Coordinately Modulate the Antioxidant System and ABA Accumulation in Mustard Plants under Salt Stress.

This study explored the interactive effect of ethephon (2-chloroethyl phosphonic acid; an ethylene source) and sulfur (S) in regulating the antioxidant system and ABA content and in maintaining stomatal responses, chloroplast structure, and photosynthetic performance of mustard plants (Brassica juncea L. Czern.) grown under 100 mM NaCl stress. The treatment of ethephon (200 µL L−1) and S (200 mg S kg−1 soil) together markedly improved the activity of enzymatic and non-enzymatic components of the ascorbate-glutathione (AsA-GSH) cycle, resulting in declined oxidative stress through lesser content of sodium (Na+) ion and hydrogen peroxide (H2O2) in salt-stressed plants. These changes promoted the development of chloroplast thylakoids and photosynthetic performance under salt stress. Ethephon + S also reduced abscisic acid (ABA) accumulation in guard cell, leading to maximal stomatal conductance under salt stress. The inhibition of ethylene action by norbornadiene (NBD) in salt- plus non-stressed treated plants increased ABA and H2O2 contents, and reduced stomatal opening, suggesting the involvement of ethephon and S in regulating stomatal conductance. These findings suggest that ethephon and S modulate antioxidant system and ABA accumulation in guard cells, controlling stomatal conductance, and the structure and efficiency of the photosynthetic apparatus in plants under salt stress.

Effects of plant growth regulators on growth, flowering, fruiting and fruit yield of cucumber (Cucumis sativus L.): A review

This review provides a comprehensive overview of the basic and applied aspects of different plant growth regulators in the regulation of growth and development of cucumber plants. The study is completely based on the use of secondary sources of data; related journals, government institutes, and relevant reports. Foliar application of PGRs has been shown to change the physiological and developmental processes, including plant vegetative growth, sex expression, yield, and yield components in cucumber. There are basically two types of growth regulators; plant growth promoters such as auxin, gibberellins, cytokinins, maleic hydrazide, ethephon, etc. and plant growth inhibitors such as ethylene, abscisic acids, dormins, etc. The combined use of auxins and gibberellins result in increased secondary growth. Maleic hydrazide (MH) along with Ethephon at 100 ppm each increases the number of nodes and primary branches. Ethrel at 300-400 ppm retards the secondary development and increase femaleness, and at 200-300 ppm make fruit surface smooth. Silver nitrate (AgNO3) at 400 ppm enhances the maleness in cucumber. Application of Ethephon at 300 ppm reduces the harvesting time of the fruit. Salicylic acid (at 2 doses of 0.07 mm/l + 0.18 mm/l) increases chlorophyll content and its exogenous application increases the fruit yield. Maleic Hydrazide (MH) alone at 100 ppm increases the femaleness, inhibits apical growth at 50-100 ppm, and increases fruit size at 200 ppm. Therefore, various auxin [indole-3-acetic acid (IAA), NAA], auxin transport inhibitor (TIBA), cytokinins (KIN), gibberellin [gibberellic acid (GA3)], ABA, ethylene [(2-chloroethylphosphonic acid (ethrel; ethephon; CEPA)] and growth retardant (MH) have been applied to control the vegetative growth and to maximize yield of cucumber. Numerous obstacles have hindered the quality cucumber production in Nepal; like environmental stresses, biotic and abiotic constraints, pest and disease outbreaks, and many others. The use of exogenous plant growth regulators has been crucial to Nepali cucumber producers as plant growth regulators has hasty effect on vegetative as well as the quality yield of plants. This study aims to reveal the suitable concentrations for the applications of growth regulators so that the use of such regulators is environmentally and toxicologically safe for both plants and the consumers.

Determination of 2-chloroethylphosphonic acid and its intermediate vinylphosphonic acid from artificially ripened sapota fruit by modified dispersive solid-phase extraction cleanup and gas chromatography/mass spectrometry analysis.

Fruit is generally ripened after harvesting using artificial ripeners such as ethylene, calcium carbide, and ethephon (2-chloroethylphosphonic acid), which can release some residues into the fruits. These residues must be within the maximum levels described in various international standards. The presence of the residues of artificial ripeners must be verified using sensitive and selective detection methods. The residues of ethephon and vinylphosphonic acid (VPA) were extracted from the pulp of sapota fruit using acetone, and the extract was treated with MgSO4 to remove residual water. The extract was subjected to dispersive solid-phase extraction cleanup using DSC-6S sorbent and graphitized carbon black mix, and the cleaned sample was evaporated to dryness and reconstituted in ether containing diazomethane. The analytes were quantitatively identified using gas chromatography/mass spectrometry. The developed method was observed to be linear in the concentration range of 1-5000 ng/g, and the limits of detection and quantification of the method were 1 and 2 ng/g, respectively, for both ethephon and VPA residues. The inter-day and intra-day precision was below 15%. The developed method was used for the quantification of ethephon residues from sapota fruit ripened with 100, 200, 500, 1000, 5000, and 10 000 mg/L solutions of ethephon, and ethephon residues were detected in the pulp samples up to a concentration of 5 ng/g. VPA residues were not detected in the fruit pulp; however, the washing solution of fruit ripened with a 10 000 mg/L ethephon solution showed VPA residues. The validated method exhibited high sensitivity for the analytes with a limit of quantification of 2 ng/g, which is lower than the described maximum residue level of 0-5 μg/g. The ethephon residues were below the maximum residue limits in the pulp of sapota fruit ripened with ethephon solutions up to 10 000 mg/L concentration.

USO DE ÁCIDO 2 -CLOROETIL- FOSFONICO PARA INDUCIR PRODUCCIÓN Y CALIDAD DE GOMA DE MEZQUITE (Prosopis laevigata)

<p><strong>Background.</strong> Mezquite gum (<em>Prosopis laevigata</em> [Humb. & Bonpl. ex Willd.]) is similar to the gum Arabic; its production is associated to the stress condition of the tree. <strong>Objective.</strong> To induce and evaluate the gum production and quality. <strong>Methodology.</strong> A completely randomized design with factorial arrangement was used, factor one was seasons (spring and autumn), factor two was tree heights (2.0 and 3.0 m) and factor three was the application of two products, acid 2 -chloroethyl- phosphone (Etherel 240<sup>®</sup>) + distilled water and a control (distilled water). <strong>Results.</strong> The gum was produced only in primary branches between 10 and 15 days after applying 2-chloroethyl phosphonic acid + distilled water. Gum production was higher in autumn in 3.0 m trees, with an average of 57 g per tree. A yield of 10.8 kg ha<sup>-1</sup> of gum with a density of 190 trees ha<sup>-1</sup> was estimated. The content of ash and protein in gum was higher in trees of 2.0 m in autumn, while the content of fiber and nitrogen-free extract in gum was higher in trees of 3.0 m in autumn. The moisture and fat content in gum was higher in spring in trees of 2.0 and 3.0 m, respectively. The pH of the gum was less acid in 3.0 m trees in spring with a lower content of impurities. <strong>Implications.</strong> It is suggested to carry out other tests to determine the presence of acid 2-chloroethyl-phosphonic in the chemical composition of the gum. <strong>Conclusion.</strong> The application of acid 2-chloroethyl-phosphonic (20%) + distilled water stimulated gum secretion in mesquite trees. Trees treated with distilled water (control) did not produce gum.</p>

A STUDY ON ELECTRICAL IMPEDANCE IN RIPENING AMBON-BANANAS (MUSA PARADISIACA VAR. SAPIENTUM) PROCESSES STIMULATED BY ETHREL (2-CHLOROETHYL PHOSPHONIC ACID)

The use of ethrel (2-chloroethyl phosphonic acid) is faster fruit maturity. Excessive use of ethrel in the ripening of bananas causes damage to the fruit and people who consume it. The principle of measurement based on electrical impedance spectroscopy can detect changes that occur in biological material. This paper discusses the comparison of the electrical impedance values of the ripeness of bananas, which marinated using various ethrel concentrations and natural maturity. The electrical impedance measurement system uses four needle electrodes made of pure silver, which are supported by the use of the V to I module and signal generator from PICOSCOPE 5244B. The system injects a current of one mA into the sample. The sample consisted of bananas through the ripening process using three ethrel concentrations of 1000 ppm and 2000 ppm. Observation of changes in fruit and impedance measurements in the range of 1 Hz to 1 MHz carried out every two days for nine days. The impedance value that correlates with the maturity of the banana well observed in the frequency range between one to 100 kHz. Increasing the impedance value describes the fruit maturity, which indicated by increasing the acidic until peak-phase and increasing sugar content until the fruit rot. The maturation process using ethrel provides the effect of shifting the peak impedance value. The higher the ethrel concentrations that used the electrical impedance value of the banana will be higher.

Postharvest quality of ‘Brookfield’ apple field-treated with naphthalene acetic acid alone or combined with other growth regulators

ABSTRACT The Gala cultivars represent about 65% of the Brazilian apple production, however, it has a short harvest period, making necessary to use technologies that anticipate or delay fruit maturation. A widely used technology is the preharvest application of growth regulators. The objective of this investigation was to evaluate the effect of preharvest application of naphthalene acetic acid (NAA) combined with aminoethoxyvinylglycine (AVG) and 2-chloroethylphosphonic acid (Ethephon), on the quality of ‘Brookfield’ apple at harvest and after eight months controlledatmosphere (CA)(1.2 kPa O2 and 2.0 kPa CO2) storage followed by seven days of shelf life at 20 °C. The treatments were: [1] Control: application of water only; [2] NAA (40 g.ha-1); [3] NAA (40 g·ha-1) plus Ethephon (2.0 L·ha-1 24% of active ingredient), and [4] NAA (40 g·ha-1) plus AVG (0.83 kg.ha-1 15% of active ingredient). At harvest, fruit treated with NAA presented a higher level of starch degradation, ethylene production and respiration rate. Fruit treated with NAA plus AVG maintained better quality after eight months under CA storage plus seven days of shelf life, due to higher healthy fruit amount and higher flesh firmness, but this combination reduced the red skin color index. Additionally, NAA plus Ethephon may be an alternative to maintain the quality of ‘Brookfield’ apple during storage in comparison to the application of NAA isolated.

Gene-specific chromatin architecture changes associates with ethylene induced germination of soybean [Glycine max (L.) Merrill

The present work aims to specifically evaluate the gene-specific chromatin architecture changes during ethylene (ET) induced germination in soybean [Glycine max (L.) Merrill]. For the same, soybean seeds were primed with 250 mg l−1 ethephon (Eth; 2-chloroethylphosphonic acid, an ET-releaser) either alone or in combination with 100 µM trichostatin A [TSA; an histone deacetylase inhibitor (HDACi) and global DNA methylation] under prescribed germination conditions. Our results demonstrated that Eth priming induced soybean germination exhibited the global as well as gene-specific chromatin de-condensation of a functional read-out gene, α-amylase 1 (GmαAMY1) alone as well as in combination with TSA, without any significant synergistic effect. Based on these observations, we propose an epigenetic role of ET as a chromatin modulator of germination-specific gene(s), which in turn lead to their corresponding up-regulation and subsequent germination and developmental changes in plants.

The quality of barley husk-caryopsis adhesion is not correlated with caryopsis cuticle permeability

Adhesion of the barley husk to the underlying caryopsis requires the development of a cuticular cementing layer on the caryopsis surface. Differences in adhesion quality among genotypes have previously been correlated with cementing layer composition, which is thought to influence caryopsis cuticle permeability, the hypothesised mechanism of adhesion mediation. It is not yet known whether differences in adhesion quality among genotypes are determined by changes in caryopsis cuticle permeability. We examined changes in candidate cementing layer biosynthetic and regulatory genes to investigate the genetic mechanisms behind husk adhesion quality. We used both commercially relevant UK malting cultivars and older European lines to ensure phenotypic diversity in adhesion quality. An ethylene responsive transcription factor (NUD) is required for the development of the cementing layer. To examine correlations between gene expression, cementing layer permeability and husk adhesion quality we also treated cultivars with ethephon (2-chloroethylphosphonic acid) which breaks down to ethylene, and silver thiosulphate which inhibits ethylene reception, and measured caryopsis cuticle permeability. Differential adhesion qualities among genotypes are not determined by NUD expression during development of the cementing material alone, but could result from differences in biosynthetic gene expression during cementing layer development in response to longer-term NUD expression patterns. Altered caryopsis cuticle permeability does result in altered adhesion quality, but the correlation is not consistently positive or negative. Cuticle permeability is therefore not the mechanism that determines husk adhesion quality, but is likely a consequence of the required cuticular compositional changes that determine adhesion.

Modulatory effects of Saussurea lappa root aqueous extract against ethephon-induced kidney toxicity in male rats.

Ethephon (2-chloroethyl phosphonic acid) is a plant growth promoter used to control the plant growth process by liberating ethylene and stimulating the production of endogenous ethylene. Medicinal plants are sources of novel drug discovery targets. Costus (Saussurea lappa) has been used as traditional Chinese medicine. The current study was conducted to examine the possible modifying effects of costus (S. lappa) root aqueous extract against kidney toxicity induced by ethephon in male rats. A total of 50 adult male rats were divided into five groups (first, control; second, costus; third, ethephon; fourth, posttreated ethephon with costus; fifth, ethephon self-healing). There is a significant increase in the serum levels of urea, creatinine, potassium ions, chloride ions, kidney injury, DNA damage, and proliferating cell nuclear antigen expressions in treated rats with ethephon when compared to the control group. In contrast, the treated rats with ethephon revealed a significant decrease in the levels of sodium ions and an insignificant decrease in the calcium ions. Saussurea lappa extract modified these alterations when compared to the control group. As a result, costus root extract significantly reduced rat kidney toxicity after ethephon administration. We recommend costus to be included in diet for its valuable effects, and also producers and consumers should become more aware about the toxic effects of ethephon.

Morphological, Transcriptomic and Hormonal Characterization of Trimonoecious and Subandroecious Pumpkin (Cucurbita maxima) Suggests Important Roles of Ethylene in Sex Expression.

Sex expression is a complex process, and in-depth knowledge of its mechanism in pumpkin is important. In this study, young shoot apices at the one-true-leaf stage and 10-leaf stage in Cucurbita maxima trimonoecious line ‘2013–12’ and subandroecious line ‘9–6’ were collected as materials, and transcriptome sequencing was performed using an Illumina HiSeqTM 2000 System. 496 up-regulated genes and 375 down-regulated genes were identified between shoot apices containing mostly male flower buds and only female flower buds. Based on gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, the differentially expressed genes were mainly enriched in the ethylene and auxin synthesis and signal transduction pathways. In addition, shoot apices at the 4-leaf stage were treated with the ethylene-releasing agent 2-chloroethylphosphonic acid (Ethrel), aminoethoxyvinyl glycine (AVG), AgNO3 and indoleacetic acid (IAA). The number of female flowers up to node 20 on the main stem of ‘2013–12’ increased significantly after Ethrel and IAA treatment and decreased significantly after AVG and AgNO3 treatment. The female flowers in ‘9–6’ showed slight changes after treatment with the exogenous chemicals. The expression of key genes in ethylene synthesis and signal transduction (CmaACS7, CmaACO1, CmaETR1 and CmaEIN3) was determined using quantitative RT-PCR, and the expression of these four genes was positively correlated with the number of female flowers in ‘2013–12’. The variations in gene expression, especially that of CmaACS7, after chemical treatment were small in ‘9–6’. From stage 1 (S1) to stage 7 (S7) of flower development, the expression of CmaACS7 in the stamen was much lower than that in the ovary, stigma and style. These transcriptome data and chemical treatment results indicated that IAA might affect pumpkin sex expression by inducing CmaACS7 expression and indirectly affecting ethylene production, and the ethylene synthesis and signal transduction pathways play crucial roles in pumpkin flower sex expression. A possible reason for the differences in sex expression between pumpkin lines ‘2013–12’ and ‘9–6’ was proposed based on the key gene expression. Overall, these transcriptome data and chemical treatment results suggest important roles for ethylene in pumpkin sex expression.

Gene-specific DNA demethylation changes associates with ethylene induced germination of soybean [Glycine max (L.) Merrill

The present work aims to evaluate epigenetic changes during ethylene (ET) induced germination in soybean [Glycine max (L.) Merrill]. Our results demonstrated that ethephon (2-chloroethylphosphonic acid, an ET-releasing compound) primed seeds exhibited: (1) DNA hypo-methylation of representative candidate genes (viz. ERF1b and AS-α1) and (2) functional restoration of DNA methylation dependent phenotype and expression of transcriptional silenced reporter transgene. Based on these observations, we proposed the novel and generic role of ET as a DNA de-methylating agent during the germination, which may lead to early developmental phenotypes in plants.

Phytoregulators in the Reproductive and Productive Characteristics of Plants and Physicochemical Characteristics of ‘Packham’s Triumph’ European Pears

The objective of this study was to evaluate the reproductive, productive and physicochemical characteristics of fruits (fruit volume and soluble solids) of ‘Packham’s Triumph’ pear trees treated with different doses of phytoregulators. The experiment was carried out in the 2014/2015 and 2015/2016 cycles, using 1-naphthaleneacetic acid (NAA), 2-chloroethyl phosphonic acid (Etefon) and 6-Benzyladenine (BA) phytoregulators, each at doses of 200 and 300 ml L-1. The experimental design consisted of a randomized block with five replicates, where each experimental unit consisted of one plant. Significance was only found for soluble solids in the 2014/2015 harvest, observing that the highest mean was identified in plants treated with 300 ml L-1 Etefon, (15 °Brix), while the lowest soluble solids content was observed with the dose of 200 mg L-1 of NAA, (11 °Brix); in the 2015/2016 crop, the highest number of inflorescences of the year was identified in plants treated with 200 ml L-1 of Etefon, (1.66) and the lowest value for the treatment with 300 ml L-1 of BA, (0.17). Effective fruiting in the value of 58.33% was also observed and verified for the plants treated with 300 mg L-1 of NAA, differing from all except from 200 ml L-1 BA. Only the plant growth regulator, NAA, at the dose of 200 mg L-1 provides low content of soluble solids in the fruits and Etefon 300 mg L-1 provides high content of solids solubles. The lowest number of branch inflorescences of the year was in plants treated with 6-Benzyladenine at a dose of 300 ml L-1 and the highest at a dose of Etefon 200 mg L-1. The NAA dose of 300 mg L-1 and 6-Benzyladenine dose of 200 ml L-1 had greater effective fruiting, but not did not reflect on the production per plant and productive efficiency. There was no benefit observed in the return bloom with the application of phytoregulators. Besides, no benefits were observed in the return bloom with the application of phytoregulators.