Application Of GA3 Research Articles

Gibberellic Acid and Silicon Ameliorate NaCl Toxicity in Brassica juncea: Possible Involvement of Antioxidant System and Ascorbate-Glutathione Cycle.

This work was carried out to observe the combined impact of exogenous applications of Gibberellic acid (GA3) and Silicon (Si) on Brassica juncea under salt (NaCl) stress. Application of GA3 and Si enhanced the antioxidant enzyme activities of (APX, CAT, GR, SOD) in B. juncea seedlings under NaCl toxicity. The exogenous Si application decreased Na+ uptake and enhanced the K+ and Ca2+ in salt stressed B. juncea. Moreover, chlorophyll-a (Chl-a), Chlorophyll-b (Chl-b), total chlorophyll (T-Chl), carotenoids and relative water content (RWC) in the leaves declined under salt stress, which were ameorialated after GA3 and Si supplementation individually and in combination. Further, the introduction of Si to NaCl treated B. juncea help in alleviating the negative effects of NaCl toxicity on biomass and biochemical activities. The levels of hydrogen peroxide (H2O2) increase significantly with NaCl treatments, subsequently resulting in enhanced peroxidation of membrane lipids (MDA) and electrolyte leakage (EL). The reduced levels of H2O2 and enhanced antioxidantactivities in Si and GA3 supplemented plants demonstrated the stress mitigating efficiency. In conclusion, it was observed that Si and GA3 application alleviated NaCl toxicity in B. juncea plants through enhanced production of different osmolytes and an antioxidant defence mechanism.

Gibberellic Acid Alleviates Cadmium-Induced Seed Germination Inhibition through Modulation of Carbohydrate Metabolism and Antioxidant Capacity in Mung Bean Seedlings

Gibberellins (GA) are the decisive players in seed germination whose functionality could be adversely affected by the presence of cadmium (Cd); however, the underlying mechanisms are unclear. Eco-toxicological effects of Cd (0, 25, 50, 75, and 100 µM) on the early stages of ontogenesis in a mung bean variety (ML-2056) were investigated. Seed germination characteristics along with Cd-tolerance index were recorded at the seventh day of germination. Additionally, endogenous gibberellic acid (GA3) level, amylase activity, oxidative stress, and the antioxidant defense system were also investigated in Cd-stressed germinating seedlings. Results revealed that Cd reduced seed germination and interfered with GA synthesis in a concentration-dependent manner. Further, to validate the role of GA in Cd-tolerance, experiments were executed to explore the effect of seed priming with GA3 and its biosynthesis inhibitor paclobutrazol (PBZ) on ML-2056 under Cd stress. Application of GA3 improved the activities of amylase and carbohydrate-metabolizing enzymes, the antioxidant defense system, and sustained lower H2O2 and TBARS contents, whereas PBZ caused a significant reduction in growth and decreased endogenous GA3 content in Cd-stressed ML-2056, suggesting a crucial role of GA synthesis in reversing Cd-induced negative effects. Overall, GA synthesis played a crucial role in mitigating Cd toxicity in mung bean, which might be used as a criterion for developing Cd-stress-tolerant genotypes.

A petunia transcription factor, PhOBF1, regulates flower senescence by modulating gibberellin biosynthesis.

Flower senescence is commonly enhanced by the endogenous hormone ethylene and suppressed by the gibberellins (GAs) in plants. However, the detailed mechanisms for the antagonism of these hormones during flower senescence remain elusive. In this study, we characterized one up-regulated gene PhOBF1, belonging to the basic leucine zipper transcription factor family, in senescing petals of petunia (Petunia hybrida). Exogenous treatments with ethylene and GA3 provoked a dramatic increase in PhOBF1 transcripts. Compared with wild-type plants, PhOBF1-RNAi transgenic petunia plants exhibited shortened flower longevity, while overexpression of PhOBF1 resulted in delayed flower senescence. Transcript abundances of two senescence-related genes PhSAG12 and PhSAG29 were higher in PhOBF1-silenced plants but lower in PhOBF1-overexpressing plants. Silencing and overexpression of PhOBF1 affected expression levels of a few genes involved in the GA biosynthesis and signaling pathways, as well as accumulation levels of bioactive GAs GA1 and GA3. Application of GA3 restored the accelerated petal senescence to normal levels in PhOBF1-RNAi transgenic petunia lines, and reduced ethylene release and transcription of three ethylene biosynthetic genes PhACO1, PhACS1, and PhACS2. Moreover, PhOBF1 was observed to specifically bind to the PhGA20ox3 promoter containing a G-box motif. Transient silencing of PhGA20ox3 in petunia plants through tobacco rattle virus-based virus-induced gene silencing method led to accelerated corolla senescence. Our results suggest that PhOBF1 functions as a negative regulator of ethylene-mediated flower senescence by modulating the GA production.

The interplay of specific hormonal profile in fruit parts of sunflower inbred lines with contrasting dormancy levels during germination and dormancy breaking by exogenous application of plant growth regulators

AbstractSunflower (Helianthus annuus L.) seed dormancy at harvest is an undesirable characteristic regarding productive systems. From a commercial point of view, the dormancy generates production and marketing problem with a negative impact on crop yields. To overcome this problem, we studied different treatments, including the application of growth regulators. In addition, as the interaction of various hormones in different sunflower fruit parts is not fully understood regarding regulation of dormancy and germination processes, we also (1) characterized the dormancy level of sunflower seeds of Xi3 and X274 inbred lines; (2) assessed the effect of exogenous growth regulators on dormancy release; (3) evaluated the endogenous content of abscisic acid (ABA), gibberellins (GAs), 12‐oxo‐phytodienoic acid (OPDA), jasmonic acid (JA), salicylic acid (SA), auxins, and cytokinins (CKs) in embryonic axis, cotyledons, pericarp, and seed coat‐endosperm; and (4) analyzed the kinetics of the accumulation of these phytohormones in Xi3 embryonic axis during early imbibition (3 to 12 h) of cypselas treated, or not, with growth regulators effective in the dormancy release. We were able to classify the two sunflower lines studied according to dormancy level: The Xi3 line was dormant and X274 line was non‐dormant at harvest. The results showed that the dormancy of Xi3 seeds is associated with a high level of ABA, OPDA, and JA, while germination of X274 dry seeds at harvest time is related to high levels of GA1. Exogenous treatment with GA3 and Ethephon overcame Xi3 seed dormancy through the changes in endogenous hormonal profiles of the embryonic axis. The exogenous application of GA3 induced JA, SA, and CKs accumulation and to modify the ABA/GA1 ratio, whereas Ethephon treatments mediated the ABA/GA1 ratio with the consequent Xi3 seed germination. Thus, the interplay of different phytohormones during early imbibition time seems to be the responsible for breaking sunflower seed dormancy.

Effects of glycyrrhetinic acid β on growth and virulence of Aeromonas hydrophila.

Aeromonas hydrophila is a significant pathogen to freshwater farmed animals, and antibiotics are usually used to control the bacterial septicemia caused by A. hydrophila. Due to the severe situation of development and spread of antibiotic resistance, there are stricter restrictions on antibiotics used in aquaculture. To evaluate the feasibility of glycyrrhetinic acid β (GA) as an alternative therapy against bacterial infection, in this study, an A. hydrophila isolated from diseased fish is used to test the antibacterial, anti-virulence activity and therapeutic effect of GA in vitro and in vivo, respectively. Results showed that GA did not affect the growth of A. hydrophila in vitro, while it could down-regulate (p < 0.05) the mRNA expression of the hemolysis-related genes hly and aerA, and significantly inhibited (p < 0.05) hemolytic activity of A. hydrophila. In addition, in vivo test showed that oral administration of GA was ineffective in controlling acute infections caused by A. hydrophila. In conclusion, these findings suggested that GA was a potential anti-virulence candidate against A. hydrophila, but the application of GA for the prevention and treatment of A. hydrophila-related diseases was still a long way.

Exogenous gibberellic acid shortening after-ripening process and promoting seed germination in a medicinal plant Panax notoginseng

BackgroundPanax notoginseng (Burk) F.H. Chen is an essential plant in the family of Araliaceae. Its seeds are classified as a type of morphophysiological dormancy (MPD), and are characterized by recalcitrance during the after-ripening process. However, it is not clear about the molecular mechanism on the after-ripening in recalcitrant seeds.ResultsIn this study, exogenous supply of gibberellic acid (GA3) with different concentrations shortened after-ripening process and promoted the germination of P. notoginseng seeds. Among the identified plant hormone metabolites, exogenous GA3 results in an increased level of endogenous hormone GA3 through permeation. A total of 2971 and 9827 differentially expressed genes (DEGs) were identified in response to 50 mg L−1 GA3 (LG) and 500 mg L−1 GA3 (HG) treatment, respectively, and the plant hormone signal and related metabolic pathways regulated by GA3 was significantly enriched. Weighted gene co-expression network analysis (WGCNA) revealed that GA3 treatment enhances GA biosynthesis and accumulation, while inhibiting the gene expression related to ABA signal transduction. This effect was associated with higher expression of crucial seed embryo development and cell wall loosening genes, Leafy Contyledon1 (LEC1), Late Embryogenesis Abundant (LEA), expansins (EXP) and Pectinesterase (PME).ConclusionsExogenous GA3 application promotes germination and shorts the after-ripening process of P. notoginseng seeds by increasing GA3 contents through permeation. Furthermore, the altered ratio of GA and ABA contributes to the development of the embryo, breaks the mechanical constraints of the seed coat and promotes the protrusion of the radicle in recalcitrant P. notoginseng seeds. These findings improve our knowledge of the contribution of GA to regulating the dormancy of MPD seeds during the after-ripening process, and provide new theoretical guidance for the application of recalcitrant seeds in agricultural production and storage.

Türk Tarım – Gıda Bilim ve Teknoloji Dergisi, 11(1): 104-111, 2023 Büyüme Geciktirici ile Yetiştirilen Dahlia Bitkilerinin Giberellik Asit ile Büyümesinin Hızlandırılması

In this study, 0, 25, 50, and 100 ppm concentrations of paclobutrazol were applied to dahlia seeds. In order to eliminate the possible retarding effects of paclobutrazol, GA3 was applied by spraying on leaves at doses of 0, 100, and 200 ppm 1 week after planting the seedlings in pots. At the end of the study, 25 ppm paclobutrazol application showed better results compared to the control (4.68 cm-67.59%) at seedling height (5.08 cm) and germination rate (80.56%). As the doses of paclobutrazol increased, there was a decrease in the specified parameters. In the second stage, although there were no statistical differences in terms of plant growth in the seedlings treated with paclobutrazol alone, 50 ppm paclobutrazol application plant height (47.87 cm) and plant stem diameter (6.55 mm), 0 ppm paclobutrazol application root wet weight (7.02 g) and 50 ppm paclobutrazol application. The application showed the best results in root length (22.70 cm). In GA3 applications at different concentrations, the 100 ppm GA3 application gave the best results in terms of plant growth compared to other applications. With the combination of paclobutrazol and GA3 applications, 50 ppm paclobutrazol and 100 ppm ga3 applications were more effective in plant growth. It was concluded that 25 ppm paclobutrazol could be used for height control of seedlings in terms of growth and flowering, and 100 ppm GA3 should be applied to eliminate possible retarding effects and quality plant growth.

Effects of Gibberellic Acid (GA3) Application on The Plant Growth and Seed Production of Pinto Peanut (Arachis pintoi Krap &amp; Greg)

Pinto peanut (Arachis pintoi Krap &amp; Greg.) is a legume that is usually used as a cover crop, bio mulch in fruit and vegetable plantations, ornamental plants, and animal feed. Pinto peanut has many benefits; through the symbiosis with rhizobacteria they can fix nitrogen, as ground cover can reduce the risk of landslides, inhibit weed growths, and is a source of nectar for bees. Arahcnis pintoi can be propagated vegetatively or generatively, but generative propagation is hard to conduct in the tropics because it takes a long time for the plants to produce seeds. Our study was conducted to determine the effect of GA3 application on seed production of A. pintoi. The experiment was arranged in a single factor randomized complete block design with GA3 concentration of 0, 75, 150, 225, and 300 ppm. An orthogonal polynomial test was conducted to determine the effective concentrations for GA3 on seed formation and seed viability. Harvested seeds were stored for 1 month, then sown on sand medium; the seeds were soaked in 1% KNO3 solution to break seed dormancy prior. Our study showed that the GA3 effective concentration range from 130.69 ppm to 137.16 ppm, indicated by the increase the number of flowers at 105, 120, 135, and 150 DAT up to 28.59% compared to control. GA3 at 126.80 ppm can also increase the number of harvested pods by 18.16%. The effect of GA3 on vegetative growth was shown by the increase in the growth of new individual plants concentration, i.e. 53.25 new individual plant with GA3 application of 141.88 ppm.

Development and validation of a chemotherapy tolerance prediction model for Chinese multiple myeloma patients: The TM frailty score.

The physical fitness of older individuals is heterogeneous, making it difficult to know their chemotherapy tolerance. The toxicities may offset the benefits of anti-myeloma therapy in frail patients. The accurate evaluation of frailty status before chemotherapy is essential. We aimed to explore the applicability of the IMWG GA and develop a new frailty screening tool more suitable for Chinese MM patients. We performed the IMWG GA and the full CGA in 167 MM patients and validated the applicability of the IMWG GA to chemotherapy and prognosis. The CGA domains were screened for their predictive value to improve IMWG GA and develop new frailty screening tools. The results showed that the IMWG GA had limitations in distinguishing the risk of grade ≥3 adverse events (AEs) between fit and int-fit patients. Of the CGA domains, TUG and MNA-SF were independent prognostic factors for grade ≥3 AEs and OS and further stratified the risk of grade ≥3 AEs in the IMWG GA int-fit subgroup (P< 0.05). We combined TUG and MNA-SF to construct the TM frailty score. The frail subgroup had a higher proportion of adverse outcomes, a higher hazard ratio (HR) in Cox regression and a higher Harrell's C-index for distinguishing the risk of grade ≥3 AEs and OS than the IMWG GA frail subgroup. The TM frailty score is more suitable than the IMWG GA for evaluating chemotherapy tolerance and prognosis in the Chinese population.

Screening of seed germination requirements of some native plants of the Mediterranean region

In the present study, we aim to investigate the seed germination conditions of three Lamiaceae widespread in the Mediterranean region and growing spontaneously in Algeria: Marrubium vulgare L., Rosmarinus officinalis L. and Thymus algeriensis Boiss. et Reut. Two experiments were carried out: (i) Ex vitro germination test: without pre-treatment. Species seeds were sowed directly in the soil under continuous darkness at 4 °C, room temperature (23±2 °C), photoperiod (16 h/light/25±1 °C, 8 h/dark/15±1 °C) and in open green house conditions. (ii) In vitro germination test was achieved by incubating sterile and soaking seeds in various doses of gibberellic acid (GA3) (0, 125, 250, 500 mg/L) under photoperiod (16 h/light/25±1 °C, 8 h/dark/15 ± 1 °C) and continuous darkness (16 h/dark/25±1 °C, 8 h/dark/15±1 °C).In ex vitro experiment, results showed that the combination of darkness and cold, ambient temperature and photoperiod did not present any significant effect (P > 0.05) on germination success rate (GSR) in the three tested species. However, low GSR (23.3%) was observed in both Thymus algeriensis and Marrubium vulgare when seed samples were placed in a greenhouse. An effective sterilization protocol was developed to successfully germinate seeds under in vitro conditions where mercuric chloride (HgCl2) was used as the most powerful sterilizing agent. In in vitro experiment, Thymus algeriensis seeds presented high GSR (66.7% to 83.3%). Furthermore, the application of GA3 at 125, 250, 500 mg/L and continuous darkness resulted in significantly high GSR (P < 0.001) in Marrubium vulgare with 68.3%, 71.6%, 73.3% and 71.7%, respectively. The interaction of GA3 at 125 mg/L and darkness significantly increased the GSR to 93.3%. In addition, GA3 doses, photoperiod-dark and the interaction GA3 × phoroperiod-dark significantly influenced the germination speed (P < 0.001) in Marrubium vulgare. While, all the treatments: GA3 doses, photoperiod-dark and their interactions did not significantly affect the seed germination (P > 0.10) in Rosmarinus officinalis, which showed a very low GSR (6.7%).

Responses of roots and rhizosphere of female papaya to the exogenous application of GA3

Exogenous GAs have an indeterminate effect on root development. Our current study used female papaya to reveal how the roots and rhizosphere respond to the exogenous application of GA3 by investigating the transcriptome profile in roots, metabolic profile and microbial community in both roots and rhizosphere of GA3-treated and control female papaya. The results demonstrated that exogenous GA3 treatment enhanced female papaya lateral root development, which gave plants physical advantages of water and nutrient uptake. In addition, it was likely that GA3 spraying in papaya shoot apices increased the level of auxin, which was transported to roots by CpPIN1, where auxin upregulated CpLBD16 and repressed CpBP to promote the lateral root initiation and development. In papaya roots, corresponding transporters (CpTMT3, CpNRT1:2, CpPHT1;4, CpINT2, CpCOPT2, CpABCB11, CpNIP4;1) were upregulated and excretion transporters were downregulated such as CpNAXT1 for water and nutrients uptake with exogenous GA3 application. Moreover, in GA3-treated papaya roots, CpALS3 and CpMYB62 were downregulated, indicating a stronger abiotic resistance to aluminum toxic and phosphate starvation. On the other hand, BRs and JAs, which involve in defense responses, were enriched in the roots and rhizosphere of GA3-treated papayas. The upregulation of the two hormones might result in the reduction of pathogens in roots and rhizosphere such as Colletotrichum and Verticillium. GA3-treated female papaya increased the abundance of beneficial bacteria species including Mycobacterium, Mitsuaria, and Actinophytocola, but decreased that of the genera Candidatus and Bryobacter for that it required less nitrate. Overall, the roots and rhizosphere of female papaya positively respond to exogenous application of GA3 to promote development and stress tolerance. Treatment of female papaya with GA3 might result in the promotion of lateral root formation and development by upregulating CpLBD16 and downregulating CpBP. GA3-treated papaya roots exhibited feedback control of brassinolide and jasmonate signaling in root development and defense. These findings revealed complex response to a growth hormone treatment in papaya roots and rhizosphere and will lead to investigations on the impact of other plant hormones on belowground development in papaya.

Histological, transcriptomic, and gene functional analyses reveal the regulatory events underlying gibberellin-induced parthenocarpy in tomato

Gibberellin (GA) is one of the major plant hormones that promote parthenocarpy, a highly valuable agronomic trait. Here, we demonstrated that exogenous GA3 application triggered the formation of parthenocarpic fruits with smaller size but unchanged shape in tomato (Solanum lycopersicum). These fruits exhibited a thicker pericarp, undeveloped ovules, and few jelly tissues, leading to smaller locules with empty cavities. Histological investigation showed that GA treatment produced more cell layers with larger cells in the pericarp, suggesting its promotion in both cell division and expansion. Transcriptomic analyses between GA3- and mock-treated unpollinated ovaries/fruits identified a large number of differentially expressed genes related to hormones, cell division, cell expansion, and transcription factors, implying that they coordinately regulated parthenocarpy conferred by GA. In particular, the downregulation of five reported repressors of tomato parthenocarpy, including two auxin signaling components, AUXIN RESPONSE FACTOR5 (SlARF5) and SlARF7, and three MADS-box genes, TOMATO APETALA3 (TAP3), TOMATO PISTILLATA (TPI), and AGAMOUS-LIKE6 (SlAGL6), after GA treatment might play a key role in this process. Furthermore, we found that the knockdown of a GA signaling factor SlMYB33, which was depressed by GA treatment, induced parthenocarpic fruit set in tomato, an effect that might have been achieved by enhancing GA biosynthesis and decreasing the expression of some repressors of tomato parthenocarpy. Thus, our results provide a basis for understanding the regulatory mechanism of GA in tomato parthenocarpy.

SEED VIABILITY, GERMINATION, AND SEEDLING GROWTH OF CAPSICUM CULTIVATED SPECIES

Seed viability of domesticated and cultivated Capsicum species: Capsicum annuum L., Capsicum baccatum L., Capsicum chinense Jacq., Capsicum frutescens L., and Capsicum pubescens Ruiz and Pav. was tested by the tetrazolium method. The seeds were soaked in three tetrazolium salt solutions of 1, 0.5 and 0.2%, and temperature conditions of 30 - 35 C for 3 h. The percentage of seeds stained in relation to the total number of seeds was evaluated. To estimate germination, the seeds were subjected to chemical treatments with gibberellic acid (GA3) at doses of 0, 100, 200, 300, and 400 mg L-1 at room temperature for 24 h. The germination rate was estimated, while plant height was evaluated at 10, 20 and, 30 days after sowing (DAS). Capsicum seed viability fluctuated between 52.44% and 97.11%. The highest percentage of viability was obtained with the 1% dose of tetrazolium (81.63%), while the 0.2% dose resulted in the lowest average value (63.7%). In addition, C. annuum, C. baccatum and C. chinense showed high staining patterns, while most of the observed patterns in C. frutescens corresponded to non-viable seeds. After GA3 application, average seed germination was 100% in C. chinense; 75.6% in C. baccatum; 73.32% in C. annuum; and 61.5% in C. frutescens. However, the application of GA3 did not cause an additional effect on the germination of Capsicum seeds. The highest plant height at 30 DAS was observed in accessions of C. annuum (9.08 cm), while C. chinense presented the lowest value (4.49 cm).

Influence of Phytohormones on Growth, Yield and Quality of tomato (Solanum lycopersicon L.) in irrigated ecosystems of Punjab, India

The present study was conducted at the research farm and Horticulture lab of Sant Baba Bhag Singh University, Punjab during the year 2020 and 2021. The experiment was conducted in a randomized block design comprising of 9 treatments (T0 - Control, T1 - GA3 @ 20 ppm, T2 - GA3 @ 30 ppm, T3 - GA3 @ 40 ppm, T4 - NAA @ 15 ppm, T5 - NAA @ 20 ppm, T6 - NAA @ 25 ppm, T7 - GA3 @ 30 ppm + NAA @ 20 ppm, T8 - GA3 @ 40 ppm + NAA @ 25 ppm) with three replications. Findings of the present study revealed that treatment T8 - GA3 @ 40 ppm + NAA @ 25 ppm resulted in highest number of leaves per plant (56), plant height (82.46 cm), number of flowers per plant (44.8), number of fruits (22.9), fruit diameter (5.83 cm), fruit weight (50.27 g), TSS (5.32 o Brix), fruit yield per plot (20.68 kg/plot) and fruit yield per hectare (344.69 q/ha). Hence, it is successfully established that the application of GA3 + NAA can be helpful in enhancing the yield and quality parameters of tomato crop thereby, improving the socio-economic status of the tomato growers.

Aplicações sucessivas de ácido giberélico em tangerineiras em alternância de produção

Abstract Gibberellins can promote the inhibition of floral induction in citrus in order to reduce alternate bearing. However, not much is known about the responsiveness of Citrus deliciosa to exogenous applications of gibberellic acid. Furthermore, the successive application of gibberellins is barely studied. The main objective of this work was to evaluate the effect of successive applications of gibberellic acid (GA3) on the reduction of spring flowering subsequent to low fruit load periods (off-year) in ‘Montenegrina’ and ‘Rainha’ mandarin trees, in southern Brazil. The treatments consisted of one to four successive applications of GA3 (40 mg L-1) with 21-day interval in off-year trees. Applications began in May and ended in July. There was a significant reduction in sprouting and flowering of ‘Montenegrina’ mandarin with more than two GA3 successive applications compared to the control. To ‘Rainha’ mandarin, only two GA3 applications reduced the sprouting and solely one GA3 application was enough to reduce sprouting in relation to the control. GA3 use reduced sprouting and flowering of Montenegrina and Rainha cultivars. The orchard age may be related to its level of alternate bearing and, therefore, to the greater or lesser sensitivity of gibberellin applications.

Study of Growth and Yield of Potato Plants (Solanum tuberosum L.) under Several Gibberellin Application during The Dry Season

Potatoes (Solanum tuberosum L.) are a vegetable crop that is the third most important carbohydrate food source in the world after rice and wheat. Potatoes growth and yield may be improved by applying plant growth regulators. This study purpose was to determine the outcome of several gibberellin plant growth regulator applications on the growth and yield of ‘Granola’ potato grown during the dry season. The study used a randomized completely block design with six factors, which were combinations of gibberellin (GA) doses and forms, namely: 1) liquid GA form with a dose of 0.1 ml.L-1, 2) liquid GA form with a dose of 0.2 ml.L-1, 3) liquid GA form with a dose of 0.4 ml.L-1, 4) powdered GA form with a dose of 0.01 g.L-1, 5) powdered GA form with a dose of 0.02 g.L-1, 6) powdered GA form with a dose of 0.04 g.L-1, and 7) Control (without GA application). All GA treatments, both liquid and powder, could increase tuber weight and yield per plot compared to the control plants. GA affects growth by increasing leaf area index, while plant height was not significantly affected. The treatment of 0.2 ml. L-1 liquid GA was the finest in producing the largest tuber size, tuber weight per plant, and tuber weight per plot. This treatment could increase the yield by 57.46% compared to ‘Granola’ that did not receive GA3 treatment. The results of this study can be used to improve potato tuber yield during the dry season.

Influence of plant growth regulators on morphological and flowering behavior of bottle gourd (Lagenaria siceraria (Mol.) Standl.)

A field experiment was conducted for evaluating the influence of three plant growth regulators (PGR) viz., gibberellic acid (GA3), Naphthalene acetic acid (NAA) and Ethrel on morphological and flowering behaviour of bottle gourd. The foliar application of Ethrel @ 300 ppm was found beneficial for days taken for appearance of first female flower, number of male flowers, number of female flowers, sex ratio. Whereas, maximum length of vine at 60 and 90 DAS, minimum number of days taken from fruit set to edible maturity was obtained by the foliage application of GA3 @ 40 ppm however minimum days taken for appearance of first male flower was obtained with GA3 @ 60 ppm. Based on these observations, it could be suggested that the significant increase in flowering and growth characters would be obtained by the spraying of Ethrel @ 300 ppm at 2-4 true leaf stage.

Uso de revestimento comestível à base de pectina contendo ácido giberélico na conservação pós-colheita de tomates frescos

ABSTRACT Edible coating are commonly used as they minimize post-harvest losses and extend the shelf life of fruits. Therefore, in this study, analyzed the effect of edible coatings containing gibberellic acid (GA3) on the shelf life of tomatoes (Solanum lycopersicum L.). Tomatoes were divided into six groups: Uncoated (CT); coating with 75 and 100 mg L-1 of GA3 solubilized in water without adding pectin (A75 and A100, respectively); coating with 75 and 100 mg L-1 of GA3 with added pectin (P75 and P100, respectively); coating pectin only (PEC). Pectin-based coatings (PEC, P75, and P100) were produced by solubilizing pectin (3%) in water, followed by adding different concentrations of GA3.Treatments A75 and A100 were prepared with distilled water and 75 and 100 mg L-1 GA3. Tomatoes (turning stage) were immersed in the solutions for 3 min, dried at room temperature, and stored at 12 °C (90% RH). The pH, titratable acidity, soluble solids, color and weight loss were analyzed every four days for 32 days, and the firmness of the tomatoes was analyzed every seven days for 35 days. Coatings with GA3 maintained firmness, delayed weight loss, and decreased acidity, pH, sugar content, and color changes. Pectin-based coatings (P75, P100) were the most effective in delaying weight loss. The application of GA3 associated with pectin-based coatings delayed the ripening process, maintained the quality, and prolonged the shelf life of fruits. As this is an inexpensive technique, it may be used commercially.

Characterization of a barley (Hordeum vulgare L.) mutant with multiple stem nodes and spikes and dwarf (msnsd) and fine-mapping of its causal gene.

Multiple nodes and dwarf mutants in barley are a valuable resource for identifying genes that control shoot branching, vegetative growth and development. In this study, physiological, microscopic and genetic analysis were conducted to characterize and fine-map the underling gene of a barley mutant with Multiple Stem Nodes and Spikes and Dwarf (msnsd), which was selected from EMS- and 60Co-treated barley cv. Edamai 934. The msnsd mutant had more stem nodes, lower plant height and a shorter plastochron than Edamai 934. Moreover, the mutant had two or more spikes on each tiller. Microscopic analysis showed that the dwarf phenotype of msnsd resulted from reduced cell lengths and cell numbers in the stem. Further physiological analysis showed that msnsd was GA3-deficient, with its plant height increasing after external GA3 application. Genetic analysis revealed that a single recessive nuclear gene, namely, HvMSNSD, controlled the msnsd phenotype. Using a segregating population derived from Harrington and the msnsd mutant, HvMSNSD was fine-mapped on chromosome 5H in a 200 kb interval using bulked segregant analysis (BSA) coupled with RNA-sequencing (BSR-seq), with a C-T substitution in the exon of HvTCP25 co-segregating with the msnsd phenotype. RNA-seq analysis showed that a gene encoding gibberellin 2-oxidase 8, a negative regulator of GA biosynthesis, was upregulated in the msnsd mutant. Several known genes related to inflorescence development that were also upregulated and enriched in the msnsd mutant. Collectively, we propose that HvMSNSD regulates the plastochron and morphology of reproductive organs, likely by coordinating GA homeostasis and changed expression of floral development related genes in barley. This study offers valuable insights into the molecular regulation of barley plant architecture and inflorescence development.

Gibberellin-induced Stem Elongation and Apical Bud Growth Acceleration Without Decreased Yield in Broccoli (&lt;i&gt;Brassica oleracea&lt;/i&gt; L. var. &lt;i&gt;Italica&lt;/i&gt;)

In Japan, broccoli (Brassica oleracea L. var. Italica) is primarily harvested manually. Some Japanese broccoli cultivars have short stems, but these broccoli heads are more difficult to harvest, and complicate the introduction of mechanical harvesters. Therefore, research is focused on strategies to control stem length. The present study examined the effects of the plant hormone gibberellin (GA) on the morphological and agronomic traits of broccoli shoots. The broccoli cultivar ‘SK9-099’, widely distributed in Japan and characterized by a short stem, was studied. These experiments were conducted over three cropping seasons, i.e., spring (Exp. 1), summer (Exp. 2), and fall (Exp. 3), with four GA treatment plots at 0 ppm (Control), 20 ppm, 100 ppm, and 500 ppm. This study observed that, on average, GA elongated stem length from approximately 16.0 cm in the control plot to 24.7 cm in the 500 ppm plot for the three cropping seasons, without decreasing yield. In addition, GA treatment accelerated apical bud growth and shortened the overall growth period by 16 days in the 500 ppm plot compared to the control in the fall, equivalent to 20.5% of the growth period from transplantation to harvest in the latter.This study highlights several practical benefits of GA application for growers, minimizing manual harvesting labor, avoid the difficult of designing mechanical harvesters for short-stemmed cultivars, and increase field usage efficiency by shortening the growth period.