Different Concentrations Of GA3 Research Articles

Unveiling the potential role of gibberellic acid, melatonin and indole acetic acid on parthenocarpy, physiological traits and phytochemical responses in Hibiscus sabdariffa L

The economic part of the Hibiscus sabdariffa L. (Malvaceae) plant is the sepal. One of the main challenges in harvesting this product is separating its seeds, which are surrounded by sepals. If the parthenocarpy process occurs without seeds, the labor costs are reduced and the profits from the production of this plant are increased. In current study, the effect of gibberellic acid (GA3), melatonin (M), and indole acetic acid (IAA) on the induction of parthenocarpy in H. sabdariffa plants was investigated. The study was conducted as a factorial experiment in the form of randomized complete block design with three replications. Different concentrations of GA3 (0 (control), 700, 800, and 900 ppm), M (0 (control), 100, 200, and 400 ppm), and IAA (0 (control), 1000, 1200, and 1400 ppm) were foliar sprayed after the emergence of the flower bud on the 50th, 60th, and 70th days of planting, and the control plants were also sprayed with distilled water. Various measurements were taken including the number of seeds per boll, parthenocarpy percentage, capsule volume, number of bolls per plant, number of mature seeds, and phytochemical parameters such as anthocyanin, chlorophyll and carotenoid content, antioxidant value, total phenol and flavonoid content, and soluble solids. The application of GA3 at 800 and 900 ppm along with IAA at 1000 ppm and M at 100 and 200 ppm led to the production of parthenocarpy fruits and showed the best results in the induction of parthenocarpy. The control group indicated the highest number of mature seeds per boll. The highest amount of phenol and flavonoid contents were obtained in plants treated with GA3 at 800 ppm. For anthocyanin, the control group showed the highest value (1.63 mg g−1), and in the case of the antioxidant trait, plants exposed to 100 ppm M showed the highest IC50 (40.68%). Hence, the application of plant growth regulators with appropriate concentrations can be effective in inducing parthenocarpy in H. sabdariffa plants. Additionally, parthenocarpy-induced by GA3, IAA, and M had different impacts on fruit quality and quantity, suggesting that the effect depends on the type of employed hormones used and their concentrations.

Effect of Gibberellic Acid and Zinc Sulphate on Growth, Yield and Quality of Cucumber (Cucumis sativus L.)

An experiment was conducted at Horticulture Research Field, Department of Horticulture, Naini Agricultural Institute, Faculty of Agriculture, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj, during February-May, 2023 on cucumber. The experiment was laid out in factorial randomized block design with twenty treatment combinations and was replicated thrice. The experiment consisted of two factors. Factor H: Hybrids (TMCU-1107, TMCU-1125, TMCU-3112 and Saira-934) and Factor T: Different concentrations of GA₃+ZnSO₄ (T0 - Control (water spray), T1 -GA₃ @100ppm+ZnSO₄ @0.25%, T2 - GA₃ @200ppm+ ZnSO₄ @0.50%, T3 - GA₃ @300ppm+ ZnSO₄ @0.75% and T4 - GA₃ @400ppm+ZnSO₄ @1%). TMCU-1125 recorded significantly higher yield attributes of cucumber over other hybrids in parameters like vine length at 80 DAS (102.6 cm), days to 50% flowering (40), days to 1st harvest (46), number of fruits per plant (11), fruit length (18.4 cm), average fruit weight (237.5 g), average fruit yield per plant (2.6 kg) and ascorbic acid content (0.8 mg/100g). Among different treatments, GA₃ @300ppm+ ZnSO₄ @0.75% resulted in significantly longer vine at 80 DAS (98.4 cm), Days to 50% flowering (43), days to 1st harvest (50), number of fruits per plant (9), fruit length (16.6 cm), average fruit weight (232.0 g), average fruit yield per plant (2.0 kg) and ascorbic acid content (0.5 mg/100g). The interaction effect of T8 (TMCU-1125 + GA₃ @300ppm+ ZnSO₄ @0.75% is best suited for getting higher growth, yield, quality of cucumber.

The Effect of Glycyrrhizin on the Viability and Proliferation of Dental Pulp Stem Cells Compared to Intracanal Medicaments.

To study the effect of glycyrrhizin (GA) on the viability and proliferation of dental pulp stem cells (DPSCs) compared with intracanal medicaments. Third molars of an adult donor were used to obtain the DPSCs. Flow cytometry was utilized to conduct phenotypic analysis for DPSCs. The methyl-thiazol tetrazolium (MTT) test was used to detect the cell viability. Cell proliferation assay was conducted at distinct time intervals: 3, 5, and 7 days. The flow cytometry analysis verified the positive expression of mesenchymal cell surface antigen molecules (CD73, CD90, and CD105) and the absence of hematological markers (CD14, CD34, and CD45) in the DPSCs. The cells that treated with concentrations more than 0.5 mg/mL of Ca(OH2) and triple antibiotic paste (TAP) gave significant decrease in viability in comparison to the untreated cells (p < 0.05). Also, the cells treated with concentrations 50 and 25 µM of GA showed no significant difference compared with the untreated cells (p > 0.05), while concentrations 12.5 and 6.25 µM expressed a significant increase in viability compared with the untreated cells (p < 0.05). At 7 days, cells treated with the three different concentrations of GA (12.5, 25, and 50 µM) demonstrated a significant increase in cell density compared with Ca(OH)2 and TAP-treated cells (p < 0.05). Based upon the potential of GA on DPSCs proliferation compared with Ca(OH)2 and TAP, It is conceivable to acknowledge that GA could be used as an intracanal medicaments for revascularization process of necrotic immature teeth. This study emphasizes the significance of assessing alternative root canal medicaments and their impact on the proliferation and viability of DPSCs. The results regarding GA, specifically its impact on the viability and growth of DPSCs, provide essential understanding for its potential application as an intracanal medicine. This study adds to the continuous endeavors in identifying safer and more efficient intracanal therapies, which are essential for improving patient outcomes in endodontic operations. How to cite this article: Alrashidi MA, Badawi MF, Elbeltagy MG, et al. The Effect of Glycyrrhizin on the Viability and Proliferation of Dental Pulp Stem Cells Compared to Intracanal Medicaments. J Contemp Dent Pract 2024;25(3):267-275.

Study on Dormant and Germination Characteristics of Chinese Olive (Canarium album) Seeds

This study aimed to determine the dormancy type of Chinese olive seeds and improve their germination rate. The water permeability and germination-inhibiting substances of Chinese olive seeds were assessed. Low-temperature stratification and soaking in a GA3 solution were implemented to measure the time lag, initial time, germination rate, and germination potential of the seeds. The findings revealed that the seed coat exhibited poor water permeability, which negatively influenced the germination rate. Additionally, Chinese olive seeds contained substances that inhibited germination. The duration of low-temperature stratification (at 4 ± 1 °C) gradually diminished the dormancy of Chinese olive seeds, resulting in early and rapid germination. The germination rate significantly increased, with the percentage of seed germination rising from 0% to 42.33% within 60 days of stratification. Furthermore, combining low-temperature stratification with different concentrations of GA3 notably enhanced the germination rate. The optimal concentrations of gibberellins for 40 and 60 days of stratification were determined to be 300 and 100 mg/L, respectively. These results indicate that Chinese olive seeds possess non-deep physiological dormancy.

Bio-efficacy and Phytotoxicity of Gibberellic Acid (GA3) Technical 90% for Improving Yield and Quality in Grapes (Vitis vinifera L.)

The experiment was conducted on Thompson Seedless grapevines grafted on dog ridge rootstock to study its response towards the application of gibberellic acid (GA3) Tech. 90% at different time intervals. The experiment was designed in a randomized block design (RBD) having five treatments with four replications were carried out at Maharashtra Rajya Draksha Bagaitdar Sangh, Pune during 2020-2021 &amp; 2021 - 2022. Significant differences were observed with the applications of GA3 at different developmental stages (pre-bloom and fruit set) resulted in to increased bunch weight, berry weight, berry length, berry size, pedicel thickness, rachis length, and quality parameters viz. total soluble solids along with the highest yield per vine exogenous application of different concentrations of GA3 at different time interval schedules was beneficial for the quality and yield of Thompson Seedless grapevines.

Genome-Wide Identification and Expression Analysis of DWARF53 Gene in Response to GA and SL Related to Plant Height in Banana

Dwarfing is one of the common phenotypic variations in asexually reproduced progeny of banana, and dwarfed banana is not only windproof and anti-fallout but also effective in increasing acreage yield. As a key gene in the strigolactone signalling pathway, DWARF53 (D53) plays an important role in the regulation of the height of plants. In order to gain insight into the function of the banana D53 gene, this study conducted genome-wide identification of banana D53 gene based on the M. acuminata, M. balbisiana and M. itinerans genome database. Analysis of MaD53 gene expression under high temperature, low temperature and osmotic stress based on transcriptome data and RT-qPCR was used to analyse MaD53 gene expression in different tissues as well as in different concentrations of GA and SL treatments. In this study, we identified three MaD53, three MbD53 and two MiD53 genes in banana. Phylogenetic tree analysis showed that D53 Musa are equally related to D53 Asparagales and Poales. Both high and low-temperature stresses substantially reduced the expression of the MaD53 gene, but osmotic stress treatments had less effect on the expression of the MaD53 gene. GR24 treatment did not significantly promote the height of the banana, but the expression of the MaD53 gene was significantly reduced in roots and leaves. GA treatment at 100 mg/L significantly promoted the expression of the MaD53 gene in roots, but the expression of this gene was significantly reduced in leaves. In this study, we concluded that MaD53 responds to GA and SL treatments, but “Yinniaijiao” dwarf banana may not be sensitive to GA and SL.

Enhanced germination of seeds native to Brazil: A comparative analysis between free and nanoencapsulated gibberellic acid in Dyckia sp. (Bromeliaceae)

ABSTRACT Brazil is home to a great diversity of species of the genus Dyckia. However, many of these species are threatened due to habitat destruction and predatory exploitation. An alternative to conserving these plants is sexual propagation using plant regulators to stimulate germination. Gibberellic acid (GA3) is an effective regulator in this process, but its instability and ease of degradation pose challenges. Therefore, nanoencapsulation of GA3 could be used to protect the molecule and allow controlled release. In this study, the effects of different doses of GA3 were evaluated on the germination of four species: D. cabrerae, D. dusenii, D. pottiorum and D. walteriana. The first stage consisted of soaking the seeds in different concentrations of GA3, in which the species D. dusenii and D. walteriana showed significant responses to GA3, with an increase from 35% to more than 60% germination. However, the species D. cabrerae and D. pottiorum responded positively to GA3 only in vegetative growth parameters. In the second stage, the use of nanoparticles of alginate/chitosan (NP ALG/CS) and chitosan/tripolyphosphate (NP CS/TPP) containing GA3 was compared with free GA3 and with NPs without GA3. It was verified that the use of nanoencapsulated GA3 resulted in a more efficient germination response in D. walteriana seeds, using smaller doses of the regulator (between 0.75 mg · L−1 and 1.0 mg · L−1), mainly with the ALG/ CS NPs. Therefore, the use of GA3 is recommended for D. dusenii and D. walteriana, and for the latter, nanoparticles containing ALG/CS-GA3 allow a reduction in the required dose.

Effect of Gibberellic Acid and Eggshell on Hylocereus polyrhizus

Dragon fruit (Hylocereus polyrhizus) is a tropical fruit. Recently, it has gained interest from the public due to its potential beneficial effects on health. The acclimatization of micropropagated Hylocereus polyrhizus depends on the application of gibberellic acid (GA3) to increase plant growth. Eggshells are waste materials from industrial sectors, and they are composed of calcium source that is vital for the development of plant shoots and root. The objective of this research is to investigate the effect of different concentrations of GA3 and eggshell either added individually or in combination on the growth of shoot length and shoot diameter of H. polyrhizus. The result showed the shoot length of the H. polyrhizus increased by approximately 54.69%, from 0.64 ± 0.13 cm to 0.99 ± 0.26 cm, as the concentration of GA3 increased from 0 ppm to 10 ppm. Furthermore, this finding also reported that with eggshells, GA3 showed an adverse effect on the development of shoot diameter. The growth of shoot length and shoot diameter with the addition of eggshell was different, perhaps due to the gibberellic acid affecting the shoot length but not the shoot diameter. Generally, the growth of shoot length and shoot diameter with eggshells was higher in comparison with those without eggshells. With that, we can prove that eggshell is a good additive to promote the growth of H. polyrhizus.

Gibberellin (GA3) and Copper Sulfate Pentahydrate (CuSO4·5H2O) Reduce Seeds per Fruit and Increase Fruit Quality in Bac Son Mandarin Fruit

The aim of this study was to find the optimal gibberellic acid (GA3) and copper sulfate (CuSO4·5H2O) concentrations to reduce the number of seeds and increase the quality of Bac Son mandarin fruit. In experiment 1, the control plants (without GA3) were sprayed with water, and the remaining plants were sprayed with different concentrations of GA3 (50, 75, 100, or 125 ppm). In experiment 2, the control plants (without CuSO4·5H2O) were sprayed with water, and the remaining plants were sprayed with different concentrations of CuSO4·5H2O (50, 75, 100, or 125 ppm). Spraying GA3 at 100 ppm in 2018 produced the lowest seed number and the highest theoretical yield. In 2019, spraying GA3 led to a lower seed number and a higher actual yield compared with the control. Similarly, spraying CuSO4·5H2O significantly reduced the number of seeds/fruit and significantly increased the theoretical yield in 2018. In 2019, the total number of seeds/fruit was significantly lower in the CuSO4·5H2O treatments than in the control. Importantly, both GA3 and CuSO4·5H2O treatments did not adversely affect the fruit’s biochemical parameters or yield. These findings demonstrate that spraying GA3 or CuSO4·5H2O at a certain concentration can effectively reduce the number of seeds per fruit in Bac Son mandarin without compromising fruit quality or yield.

Integrated morphological, metabolome, and transcriptome analyses revealed the mechanism of exogenous gibberellin promoting petiole elongation in Oenanthe javanica.

Oenanthe javanica (Blume) DC. is a popular vegetable with unique flavor and its leaf is the main product organ. Gibberellin (GA) is an important plant hormone that plays vital roles in regulating the growth of plants. In this study, the plants of water dropwort were treated with different concentrations of GA3. The plant height of water dropwort was significantly increased after GA3 treatment. Anatomical structure analysis indicated that the cell length of water dropwort was elongated under exogenous application of GA3. The metabolome analysis showed flavonoids were the most abundant metabolites and the biosynthesis of secondary metabolites were also regulated by GA3. The exogenous application of GA3 altered the gene expressions of plant hormone signal transduction (GID and DELLA) and metabolites biosynthesis pathways to regulate the growth of water dropwort. The GA contents were modulated by up-regulating the expression of GA metabolism gene GA2ox. The differentially expressed genes related to cell wall formation were significantly enriched. A total of 22 cellulose synthase involved in cellulose biosynthesis were identified from the genome of water dropwort. Our results indicated that GA treatment promoted the cell elongation by inducing the expression of cellulose synthase and cell wall formation in water dropwort. These results revealed the molecular mechanism of GA-mediated cell elongation, which will provide valuable reference for using GA to regulate the growth of water dropwort.

Exogenous hormone application regulates dwarf mutant plant height in Sophora davidii (Franch.) Skeels by changing endogenous hormone levels

Dwarf mutants are valuable materials for investigating plant gene function and developing new crop varieties. In the present study, dwarf mutant (D-CK) and wild-type (W-CK) Sophora davidii (Franch.) Skeels plants foliarly sprayed with distilled water were used as controls, and dwarf mutants were treated with different concentrations of gibberellin A3 (GA3; 20, 40 and 60 mg L-1), brassinosteroid (BR; 12.5, 25 and 50 mg L-1); and auxin indole-3-acetic acid (IAA; 12.5, 25 and 50 mg L-1) to study the changes in plant height at 20, 40 and 60 d after exogenous hormone spraying. The changes in endogenous contents of IAA, GA3, BR, abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA) and IAA:ABA ratio in the dwarf mutant plants were also measured at 20, 40 and 60 d after exogenous hormone application. The dwarf mutants reverted to the W-CK height phenotype after 60 d of exogenous spraying with different concentrations of GA3 and BR (except 50 mg·L-1), but after exogenous spraying with IAA, dwarf mutants did not revert to the W-CK height phenotype. Compared with D-CK plants, endogenous GA3, BR and IAA contents in dwarf mutant plants increased to some extent with exogenous spraying of GA3, BR and IAA. The results indicated that exogenous spraying of different concentrations of GA3 and BR regulated S. davidii plant height by promoting the secretion of endogenous GA3, BR, IAA and SA and inhibiting endogenous ABA secretion in dwarf mutant. The height of mutants was sensitive to exogenous GA3 and BR but not to exogenous IAA.

The Effect of Different Concentrations of GA3 and NAA on Growth and Flowering of Asiatic Lily (Lilium × asiatica) cv. Litouwen under Naturally Ventilated Polyhouse Conditions of Prayagraj

This investigation was conducted under a naturally ventilated polyhouse, in the Department of Horticulture, SHUATS, Prayagraj, Uttar Pradesh. In December 2020 with records taken from the month of February to month of March 2021. There were nine treatments comprising two growth regulators Gibberellic acid (GA3) (at 200, 250, 300, and 350 ppm), and Naphthalic Acetic Acid (NAA) (at 50,100,150, and 200 ppm) along with control. The whole experiment was laid out as a Randomized Block Design (RBD) with three replications. The results revealed that among the Lilium cv. LITOUWEN, the foliar application of 250 ppm GA3 significantly increased the number of leaves per plant (66) with enhanced days to bud initiation (25.7 days). The number of bud per plant was 2.8 and stem length was 43.4cm respectively., GA3 at a concentration of 350 ppm enhanced vase life (7.9 days). and NAA at a concentration of 100 ppm enhanced the number of bulblets (3.3).

Effect of Deteriorated Seed Soaking with Different Concentrations of Gibberellin (GA3) on Germination and Seedling Growth of Two Oat (Avena sativa L.) Cultivars

A factorial experiment with two factors was carried out at the Seed Technology Lab., College of Agriculture, University of Baghdad in 2018 in order to study the effect of seed priming with gibberellic acid (GA3) (0, 100, 300 and 500 mgL-1) on germination and seedling growth of deteriorated seed of two oat cultivars (Shifaa, and Shofan11). The complete randomized design was used with four replications. The results showed that cultivars, soaking in different concentrations of GA3 and their interactions had a significant effect on studied traits. Shofan11, GA3 (500 mg L-1) and their interaction gave the highest values of germination ratio (74.1, 85 and 85%), lengths of radical (7, 8.5 and 8.6 cm) and plumule (9.3, 10.8 and 10.9 cm), fresh (71.95, 74.74 and 74.76 mg) and dry (18.41, 23.14 and 25.07 mg) weights of seedling and seedling vigour index (1270.2, 1644 and 1655.5), respectively. It can be concluded that soaking of deteriorated seed with GA3 led to increasing germination ratio and improved seedling growth in oat.&#x0D; &#x0D;

Gibberellic Acid Enhances the Germination and Growth of Maize under Salinity Stress

Soil salinity is the major limiting factor restricting plant growth and development. Little is known about the comparative and combined effects of gibberellic acid (GA3) seed priming and foliar application on maize under salt stress. The current study determined the impact of different concentrations of GA3 on morpho-physiological and photosynthetic attributes of maize seedlings under salinity stress treatments (no salinity and severe salinity-15 dSm-1). The GA3 treatments consisted of 1mM, 2mM, 3mM, 4mM and 5mM GA3 seed priming and exogenous application in salt condition. Salt stress particularly at 15 dSm-1 reduced the length of shoots and roots, fresh and dry weights, chlorophyll, lycopene, beta-carotine and carotenoid contents in maize plants. Nevertheless, the application of GA3 improved maize growth under salt stress. Compared with salt, the 2mM GA3 treatment (T4) recorded the highest increase in roots and shoots length, roots fresh and dry weights, shoots fresh and dry weights, chlorophyll content under salt stress compared to other concentrations. These results indicated that 2mM GA3 priming and exogenous application could be used as an effective tool for improving the maize growth and development in salt contaminated soils.

Vegetative Growth, Yield and Quality of Broccoli As Influenced by Application of Gibberellic Acid

Field experiments on broccoli cv. ‘BARI Broccoli-1’ was carried out during two consecutive rabi seasons of 2014-15 and 2015-16 at the field of Plant Physiology Section of HRC, BARI. 30 days old seedlings were treated before transplanting by dipping their roots for 24 h in different concentrations of GA3 (Gibberellic acid) viz., 20, 40, 60, 80 and 100 ppm along with control (distilled water). The experiment was laid out in a Randomized complete block Design with three replications. GA3 concentrations significantly influenced the growth parameters, yield and yield attributes and quality parameters of broccoli. In regard to the average data of two years, GA3 @ 60 ppm gave the maximum leaf length (46.58 cm), spread diameter (52.38 cm), head circumference (38.2cm cm), head length (16.60 cm), head diameter (15.45 cm), primary and secondary head weight/plant (289.85 g and 192.80 g). The maximum head yield (18.82 t/ha in 2014-15 and 21.39 t/ha in 2015-16) with an average of 20.11 t/ha was recorded at GA3 @ 60 ppm followed by GA3 @ 40 ppm. Application of GA3 @ 60 ppm also produced the highest head compactness index (18.77 g/cm), maximum vitamin C (82.88 mg/100 g FW), vitamin A (601.90 IU/100 g FW) contents and the highest total soluble solid (10.10%). From the investigation it was also observed that application of more than 60 ppm GA3 reduced the yield attributes and yield of broccoli.&#x0D; Bangladesh J. Agril. Res. 45(3): 247-259, September 2020

Breaking Dormancy and Enhancing Germination of Avena sterilis L. and Amaranthus retroflexus L. Weeds by Gibberellic Acid and Potassium Nitrate to Keep Soil and Crops Healthy

Soils infested with weed seeds are considered hostile lands for crop production. In this context, great wild oat (Avena sp.) in winter seasons and redroot pigweed (Amaranthus sp.) in summer seasons represent problematic weeds in cropland fields. In a series of laboratory trials, we estimated the effects of gibberellic acid (GA3) and potassium nitrate (KNO3) on germination and seedling growth of Avena sterilis L. and Amaranthus retroflexus L. Different concentrations of GA3 and KNO3 were evaluated in randomized complete block design with four replicates. Findings revealed that GA3 at a rate of 200 mg L−1 along each of 150 and 250 mg L−1 treatment showed the maximum increases in germination percentage, radicle length, plumule length and seedling dry weight of A. sterilis L. All applied concentrations of KNO3 were similar (p ≥ 0.05) in enhancing seed germination of A. sterilis L. exceeding the control treatment. Application of GA3 at rates of 250, 500 and 750 mg L−1 surpassed the treatments of 0 and 1000 mg L−1 GA3 for activating A. retroflexus L. seeds germination. Addition of 250 and 500 mg L−1 KNO3 were the potent treatments for stimulating the radicle length of A. retroflexus L. It could be concluded that for breaking dormancy efficiently, addition of gibberellic acid or potassium nitrate with Avena sterilis L. as well as gibberellic acid with Amaranthus retroflexus L. is recommended. Such chemicals could be involved in weed management programs, since distinctive promotion of seed germination for the target weeds was achieved. This undoubtedly will keep the soil and crops healthy.

Effect of Growth Regulators on Seedlings Growth of Apricot (prunus Armeniaca L.)

This study was conducted during the growing season of 2021 and 2022 in horticulture station located at Akre city center Duhok Iraqi Kurdistan region, the study was aimed to investigate the effect of growth regulators on seedling growth of apricot and determined the best concentration of Gibberellin, Benzyl adenine and Kinetin to improve vegetative growth of seedling of apricot . so it consisted of three concentration of GA3 (0, 250 and 500 mg.L-1), BA (0,150 and 300 mg.L-1), KIN (0,150 and 300 mg.L-1) on some vegetative growth characteristics of apricot seedlings (Prunus armeniaca L.).The best results include the following. apricot seedlings sprayed with different concentrations of GA3 significantly affected and gave the seedling height, number of leaves, dry weight, single leaf area and total chlorophyll. Also, seedling sprayed with different BA concentration effected significantly and gave the highest seedling diameter, number of leaves, single leaf area, and dry weight. Whereas seedling spray with different KIN concentrations significantly affected on seedling diameter and total chlorophyll. Generally, interaction between GA3 and KIN and interaction between GA3 and BA and the interaction between BA and KIN was effected significantly on most growth parameters. The best result was in the treatment (GA3 500 mg.L-1 + BA 300 mg.L-1 + KIN 150 mg.L-1) which significantly affected on all growth parameters (seedling height, seedling diameter, single leaf area, total chlorophyll, number of leaves and dry weight)

Cattleya tigrina (Orchidaceae) in vitro regeneration: Main factors for optimal protocorm-like body induction and multiplication, plantlet regeneration, and cytogenetic stability

The induction and subsequent regeneration of protocorm-like bodies (PLB) is the most common morphogenetic pathway for orchid micropropagation. The regeneration of plants from PLB can be a bottleneck for some species due to asynchronicity. Genetic fidelity is another issue, and the cytogenetic stability of regenerated plantlets deserves special attention due to the common occurrence of endopolyploidy in orchids. In the present work, we defined optimal conditions for PLB induction and plant regeneration for Cattleya tigrina, a threatened orchid from the Brazilian Atlantic Rain Forest. We estimated the optimum thidiazuron (TDZ) concentration for PLB induction from leaf explants, while also comparing whole leaves vs thin cell layer (TCL) as explants. For plantlet regeneration from PLB clusters, we investigated the effects of different concentrations of GA3 and sucrose, as well as the dehydration of PLBs and the use of temporary vs continuous immersion systems. Furthermore, the cytogenetic stability of regenerated plantlets was analyzed using flow cytometry, and the differences in stomatal morphology were studied. Exogenous TDZ (25 µM) was the most effective concentration for PLB induction, with 17.5% induction rate. Leaf basal regions, either in whole leaves or in TCL, were the most responsive for PLB induction. The dehydration of PLBs for 120 min increased the fresh weight increment (FWI) in plantlet regeneration, but at the expense of decreased shoot number and increased mortality. Temporary-immersion bioreactors were found to be the most suitable system for PLB multiplication compared to continuous immersion system. Shoot development was challenging due to previously acquired habituation to TDZ. Sucrose and GA3 showed an interactive effect on shoot growth. GA3 improved shoot formation, and maximum shoot production was estimated to occur at 10.3 and 9.7 µM GA3 on media containing 1.5% and 2% sucrose, respectively, resulting in larger number of developed plantlets (∼220) per culture flask. The flow cytometry analysis showed that 26.5% of plants regenerated from PLBs had doubled ploidy levels. The ploidy alterations were reflected in changes on leaf epidermis, such as increased stomatal density and number.

Improving Discharge Voltage of Al-Air Batteries by Ga3+ Additives in NaCl-Based Electrolyte.

The application of NaCl-based aluminum-air batteries is limited due to the passivation of the aluminum anode. In an effort to solve this problem, this work studied the influence of different concentrations of Ga3+ additives on the discharge behavior of Al in the NaCl electrolyte. The results of both experiments and theoretical calculations have shown that commercial purity aluminum could be significantly activated by Ga3+. Based on microstructure observations and electrochemical impedance spectroscopy, the influence activation mechanism of Ga3+ on the discharge behavior of commercial purity Al is clarified. The addition of Ga3+ biased the surface charge of aluminum along the activation direction, forming activation sites, and then destroyed the surface passivation film. Due to the formation of a gallium–aluminum amalgam, the Al-air battery had the best discharge characteristics in the electrolyte with 0.2 M Ga3+, and its discharge voltage reached 0.9734 V with a remarkable increase compared with that of NaCl solution (0.4228 V). Therefore, Ga3+ additive is a promising choice for NaCl-based Al-air batteries to improve their discharge voltage.

Effect of Foliar Application of GA3, on Biochemical Changes of Indian Mustard [Brassica juncea (L.) Czern. &amp; Coss.] under Sodic Soil

The investigation on effect of foliar application of GA3, on biochemical changes of Indian mustard under sodic soil, was conducted during the rabi season, at the Main Experiment Station Farm of ANDUAT, Kumarganj, Ayodhya-224229 (UP) in randomized block design with 8th treatments, three replications &amp; variety Narendra rai (NDR-8501). Different concentrations of GA3 (15ppm, 30ppm, 45ppm, 60ppm, 75ppm, 90ppm, 125ppm) were taken along with Distilled water control. Foliar spray was done at 30 Days after sowing. Observations to be recorded at 40, 60, 80 days after sowing of biochemical parameters like chlorophyll content, nitrate reductase, peroxidase, and catalase activities in green leaves were taken. Sprayed of different concentrations of GA3 increased all characters of the crop. All the parameters viz. To the studies of biochemical parameters were high recorded with foliar spray of GA3 125ppm followed by foliar spray with GA3 90ppm over rest of the treatments together with control, during the analysis.