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The yellow (Passiflora edulis) and sweet (Passiflora alata) passion fruit plants hold significant economic importance in tropical fruit cultivation, valued not only for the quality of their fruit but also for their medicinal properties. Conventional propagation through seeds faces challenges due to irregular and slow germination, affecting the time required for seedling formation and the viability and uniformity of plantations. The use of plant growth regulators has been explored as a strategy to overcome these barriers, improving both the rate and uniformity of seed germination. This study aimed to evaluate the influence of seed imbibition with plant growth regulators on the germination and subsequent growth of yellow and sweet passion fruit seedlings. Gibberellic acid (GA3) and GA4+7 combined with 6-benzyladenine (GA4+7+6BA) were applied in five different concentrations (0, 250, 500, 750, and 1000 mg L−1 a.i.). The experiments were conducted in both laboratory and greenhouse conditions, following a completely randomized design with a 2 × 5 factorial scheme. The varieties tested were 'BRS Mel do Cerrado' for sweet passion fruit and 'IAC-275' for yellow passion fruit. Quantitative parameters, such as germination percentage, germination speed index, fresh and dry biomass of roots and shoots, and enzymatic activity, were assessed. The results indicated that GA3, at higher concentrations, significantly enhanced both germination percentage and speed index in both Passiflora alata and Passiflora edulis when compared to the control. Additionally, seedlings treated with GA3 showed a marked increase in shoot and root biomass, particularly at concentrations of 500 and 750 mg L−1. Enzymatic assays revealed heightened catalase and peroxidase activities in treated seedlings, indicating improved stress tolerance. In contrast, the GA4+7+6BA treatment showed less pronounced effects on seedling growth. Overall, GA3 was more effective in enhancing germination and seedling growth in both species, suggesting its potential application in improving the propagation of passion fruit. [ABSTRACT FROM AUTHOR]

The propagation of citrus seedlings is accomplished through grafting, utilizing seeds for the production of rootstocks. The germination of certain seeds may be low and uneven, complicating the production of high-quality seedlings. The use of plant growth regulators (PGRs) is a viable alternative to improve the quality of seedling production, as these compounds can break dormancy, control the hydrolysis of reserves, induce cell division, and regulate permeability and protein functions. This study aimed to evaluate the germination of seeds and the growth of Rangpur lime (Citrus limonia L. Osbeck) seedlings under the influence of imbibition in solutions of gibberellic acid (GA3) and a combination of GA4+7 + 6Benzyladenine. The experiment was conducted under controlled laboratory and greenhouse conditions, using a completely randomized design in a 2 × 5 factorial scheme, with two types of plant regulators (GA3 and GA4+7 + 6BA) at five concentrations (0, 250, 500, 750, and 1000 mg L−1 a.i.). Quantitative and qualitative variables were evaluated, ranging from seed germination to seedling development and formation, including germination percentage and speed index, fresh and dry biomass of roots and shoots, enzymatic activity, and gas exchange. The results indicate that GA3 significantly accelerates the germination process of Rangpur lime cv. Santa Cruz seeds and promotes better seedling growth and development, resulting in vigorous seedlings. These findings demonstrate that the application of PGRs, particularly GA3, can substantially enhance the propagation efficiency of citrus rootstocks, offering a practical solution for improving the uniformity and quality of seedling production in commercial settings. [ABSTRACT FROM AUTHOR]

Plant growth regulators play an essential role in plants' biochemical processes. In this study, foliar spray was applied using three growth regulators, gibberellic acid (GA3), naphthalene acetic acid (NAA), and 6-benzyl amino purine (BAP), to investigate their effects on wheat (Triticum aestivum L.) 'Giza-171' yield traits and grain biochemical constituents, including sugars, carbohydrates and protein. The assessed growth regulators (GA3, NAA, and BAP) were applied at 100 and 150 mg L-1 concentrations. The results indicated significant improvements in wheat grain yield and 1000-grain weight, which increased by 15.40% and 24.78%, respectively, using GA3 at 150 and 100 mg L-1. In addition, the highest contents of protein and carbohydrates were observed with samples treated by the foliar application of NAA at 150 mg L-1 and BAP at 100 mg L-1, respectively. The fat content in wheat grains increased by 1.97% and 2.73% with foliar spray with 150 mg L-1 NAA and 100 mg L-1 BAP, respectively. The lipid profile showed cis-linoleic acid was the primary fatty acid, followed by palmitic acid; the content of linoleic acid slightly increased with GA3 treatment to 50.42%, while palmitic acid significantly increased with 100 mg L-1 NAA. The total saturated and unsaturated fatty acids recorded 33.64% and 66.30%, respectively; the 150 mg L-1 NAA treatment had the lowest saturated fatty acid content. The SDS-PAGE profiles showed that growth regulators significantly enhanced the wheat protein where new bands appeared, especially in 100 mg L-1 GA3 and 100 mg L-1 BAP treatments. The applied growth regulators improved wheat yield, contents of some compounds, and nutritional value. [ABSTRACT FROM AUTHOR]

The present study was conducted at the instructional cum research farm of the Department of Plantation Crops and Processing of Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, India during rabi season for consecutive two years (October-2019 to March-2020 and October-2020 to march-2021) to investigate the "Effect of Different Plant Growth Regulators on Quality attributes of Garlic (Allium sativum L.)" with various growth regulators (GA3 @ 50 ppm, GA3 @ 100 ppm, GA3 @ 150 ppm, NAA @ 50 ppm, NAA @ 100 ppm, NAA @ 200 ppm, Kinetin @ 10 ppm, Kinetin @ 20 ppm, Kinetin @ 40 ppm and Control (Distilled water). In view of, effect of different plant growth regulators on quality attributes has observed significant variation. Results pertaining to total soluble solids, significantly highest TSS recorded under GA3 @100 ppm treated plots (32.10 °Brix), however, dry matter content of bulb was highest at GA3 @ 50 ppm (33.63%). Interestingly, highest oleoresin content of the bulb was also reported from the GA3 @ 50 ppm treated plots (0.24 g) with lowest physiological loss of bulb weight (7.04%). The control plots treated with distilled water was produced qualitatively inferior bulbs. The aim of the study provided valuable results to determine the potential growth regulator for enhancing post-harvest quality attribute of garlic by employing methodology of Randomized Block Design comprising of three replications with ten treatments. Based on the current experimental results, it may be concluded that foliar application of GA3 @ 50 ppm proved the best over other plant growth regulators. [ABSTRACT FROM AUTHOR]

The nutritional value of blue honeysuckle (Lonicera caerulea L.) fruit is abundant; however, its production faces challenges due to a short harvesting period and fruit drop issues. In this study, the effects and potential mechanisms of two different plant growth regulators, GA3 (Gibberellins acid) and 2,4-D (2,4-Dichlorophenoxyacetic acid), on blue honeysuckle fruit abscission and abscission layer formation were investigated. The main cultivated variety of blue honeysuckle, 'Berel', was used as the experimental material. GA3 and 2,4-D were sprayed on the plants from the veraison. The anatomical structure of the fruit abscission zone (FAZ) was observed after treatment. Key enzymes involved in cell wall degradation, pectinase, cellulase, polygalacturonase, and pectin methylesterase, were analyzed for their activities. Furthermore, the gene expression levels of cell wall detachment-related genes CX1, CX2, PL20, PE, and key genes for gibberellin and ethylene synthesis GA2OX1, GA1, ACO, and ACO3 were examined. The results indicated that the application of GA3 and 2,4-D could delay the formation of the abscission layer. In the FAZ treated with GA3 and 2,4-D at 5 DAT, the activity of key enzymes involved in cell wall degradation decreased, the expression of genes related to cell wall degradation enzymes and key genes for ethylene synthesis was inhibited, and the drop of fruit reduced. In conclusion, exogenous application of GA3 and 2,4-D suppresses the abscission of 'Berel' blue honeysuckle fruit, likely through the inhibition of cell wall degradation and abscission layer formation. [ABSTRACT FROM AUTHOR]

Citrus is one of the most important and widely grown fruit crops around the world. Citrus fruit drop is due to the influence of various biotic and abiotic factors. Major biotic factors include insects like fruit flies and diseases such as Huanglongbing (HLB) and postbloom fruit drop (PFD) due to Colletotrichum acutatum. The associated abiotic factors are temperature, rainfall, hailstorms, water stress, nutritional imbalance, etc. Studies have been conducted to understand fruit drop and its relation to various plant growth regulators. Plant growth regulators such as auxin and gibberellins have been categorised as abscission inhibitors, while ethylene, abscisic acid (ABA) and methyl jasmonate (MJ) are abscission promoters. Here, in this review, we have emphasised on the different phases of fruit drops, factors causing fruit drop, the role of plant growth regulators, fruit detachment force (FDF), rootstocks, water relation, nutrient status and different chemical, biological, botanical and hormonal strategies applied for controlling citrus fruit drop. Moreover, we have also discussed the molecular basis of citrus fruit drop and have reviewed recent studies involving biosynthesis/signalling pathway genes and phytohormone genes affecting fruit drop. This review offers comprehensive information about citrus fruit drop and shall provide the direction of future research for students, horticulturists, researchers and other stakeholders. [ABSTRACT FROM AUTHOR]

In newly reclaimed sandy lands, plants face substantial environmental challenges, affecting their productivity, yield, and quality. Gibberellic acid (GA3) is a plant growth regulator physiologically involved in plant responses to abiotic stresses. As agricultural activities expand in desert regions, applications of GA3 could help address adverse plant growth and developmental effects. Here, we investigated the impact of exogenously applied GA3 on the growth of Cape gooseberry (Physalis peruviana L.) in newly reclaimed sandy lands in the arid Nubaria region of the West Delta of Nile, Egypt. Different GA3 concentrations of 100, 150, 200, and 250 ppm were foliar-applied to the plants. The application of GA3 in our study significantly improved the vegetative growth, plant height, leaf and branch count, and the fresh weight and yield of Cape gooseberry plants. Fruit weight, quality soluble solids, and leaf chlorophyll content were also improved. The most pronounced effects were achieved with concentrations of GA3 at 200 and 250 ppm, with the 200-ppm concentration displaying superiority in most parameters. Notably, GA3 treatments enhanced relative water content (RWC), an indicator of water status in arid conditions. Maintaining optimal RWC is crucial for essential processes like photosynthesis, promoting growth, and productivity. This research underscores GA3's potential in enhancing Cape gooseberry growth, yield, and quality, providing a practical strategy for mitigating environmental challenges in arid regions, a concern exacerbated by climate change. [ABSTRACT FROM AUTHOR]

Fall armyworm (FAW) Spodoptera frugiperda is currently being considered as a serious insect pest in maize that causes significant yield losses worldwide. Silicon (Si) and plant growth regulators (PGRs) are known to induce resistance against biotic and abiotic stresses thereby enhancing the yield. This study was conducted to determine the influence of Si and PGRs on the incidence and damage of FAW on maize (Zea mays L.) under field condition. The experiment was conducted in both Kharif and Rabi seasons using a randomized complete block design with three replications and treatments. Various combinations of foliar silicic acid (FSA) and two PGRs such as gibberelic acid (GA3) and jasmonic acid (JA) were tested to study their effects on FAWincidence and maize yield. The application of FSA at 2mL/plant + GA3 at 0.5 mg/plant recorded the lowest number of larvae per plant (0.39 larva/plant) with the lowest damage score of 2.55 (Davis scale). The percent infestation was also low for the same treatment, i.e., 34.14 percent infestation with the highest percent reduction over control (56.43%). The highest yield (58.39 q/ha) and cost-benefit ratio (1:2.34) was recorded for FSA at 2 mL/plant + GA3 at 0.5 mg/plant, which was considered as the best treatment. This study demonstrated that exogenous application of Si along with PGRs has significant negative effect on field incidence of FAW and enhanced the yield of maize. [ABSTRACT FROM AUTHOR]

Anatolia is one of the important production areas of garlic. Garlic production is conducted by using the head or the cloves inside the heads, which are actually the consumed part of the garlic, as propagation material. However, due to the use of cloves, which are the most valuable part of the market, as reproduction material, the profit is reduced by about 10%. The study aims to provide an alternative propagation material to reduce the losses resulting from this practice in local Kahramanmaraş garlic production. For this purpose, generating plantlets directly from stem discs of the garlic cloves in vitro and the effects of different growth regulators have been studied. For this, the plant growth regulators added to MS media as BAP (1.0, 1.5 and 2.0 mg l-1), GA3 (0.5, 1.0 and 1.5 mg l-1), 2-IP (0.75, 1.00 and 1.25 mg l-1); kinetin (1.0, 2.0 and 3.0 mg l-1) and TDZ (0.75, 1.00 and 1.25 mg l-1) were tested. In the study number of explants, number of infected explants, number of healthy explants, number of developed explants, healthy explant rate, developed explant rate, number of callused explants, callus growth rate, number of proliferated explants, proliferation rate, proliferation number, number of rooted explants, rooting rate and number of roots were investigated. However, shoot ratios, shoot numbers, and callus formation were the main focus. The highest rates of proliferation were found in 2-IP (53.8%, 45.5%, and 40.0% at 1.00, 0.75, and 1.25 mg l-1 dosages, respectively) and Kinetin (35.3% at 2.00 mg l-1). The maximum shoot number was reached with 2-IP at the dose of 1.00 mg l-1 as 1.9 shoot/explants. Kinetin at 3.00 mg l-1 and 2IP at 1.25 mg l-1 were the other successful applications with 1.8 shoots. This study indicated promising results to obtain plantlets directly from the clove's stem discs and including them into seedling production for the mass production of garlic. [ABSTRACT FROM AUTHOR]

Gibberellins (GA) and paclobutrazol (PBZ) are plant growth regulators. GA promotes plant growth and development while PBZ retards plant growth. Little is known about their effects on chlorophyll synthesis and photosynthesis in young oil palm plantlets. In this study, ten-month old young clonal palms were treated with 0.02 g/palm either gibberellic acid (GA3) or PBZ. The PBZ-treated palms were shorter with compact crown, shorter fronds and leaflets, more fronds and higher Soil Plant Analysis Development (SPAD) units, particularly at time point T1. Thus, PBZ suppressed elongation in leaflets, rachis and trunk but increased fronds production and leaf chlorophyll content. Contrastingly, GA3 promoted oil palm height with significant inter-leaflet elongation and lower frond production. Chlorophyll content was also adversely affected in GA3-treated palms at time point T1. Transcriptome sequencing revealed that differentially expressed genes (DEGs) were enriched for metabolic related activities. These genes were mostly downregulated by GA3 treatment. The GA3 treatment also reduced expression of chlorophyll synthesis genes, DEGs encoding components of the photosystems I (PSI) and II (PSII) supercomplexes, cytochrome b6f, Adenosine tri-phosphate (ATP) synthase and Rubisco as well as their assembly factors, translocons and photoreceptors. Meanwhile, PBZ treatment increased expression of geranylgeranyl diphosphate reductase that may inhibit GA biosynthesis but increase chlorophyll synthesis, which was likely correlated to increased chlorophyll content in the darker green leaves of PBZ-treated palms. [ABSTRACT FROM AUTHOR]

Gibberellin, as one of the pivotal plant growth regulators, can improve fruit quality by altering fruit size and secondary metabolite content. Flavonoids are the most abundant secondary metabolites in grapes, which influence the color and quality of the fruit. However, the molecular mechanism of whether and how GA3 affects flavonoid metabolism has not been reported, especially for the 'Red globe' grape with delayed cultivation in Hexi corridor. In the present study, the 'Red globe' grape grown in delayed facilities was sprayed with 20, 40, 60, 80 and 100 mg/L GA3 at berries pea size (BPS), veraison (V) and berries ripe (BR), respectively. The results showed that the berry weight, soluble sugar content and secondary metabolite content (the flavonoid content, anthocyanin content and polyphenol content) at BR under 80 mg/L GA3 treatment were remarkably increased compared with other concentration treatments. Therefore, RNA sequencing (RNA-seq) was used to analyze the differentially expressed genes (DEGS) and pathways under 80 mg/L GA3 treatment at three periods. GO analysis showed that DEGs were closely related to transporter activity, cofactor binding, photosynthetic membrane, thylakoid, ribosome biogenesis and other items. The KEGG enrichment analysis found that the DEGs were mainly involved in flavonoid biosynthesis and phenylpropanoid biosynthesis, indicating GA3 exerted an impact on the color and quality of berries through these pathways. In conclusion, GA3 significantly increased the expression of genes related to flavonoid synthesis, enhanced the production of secondary metabolites, and improved fruit quality. In addition, these findings can provide a theoretical basis for GA3 to modulate the accumulation and metabolism of flavonoids in grape fruit. [ABSTRACT FROM AUTHOR]

• Exogenous application of five plant growth regulators (stimulant, stem retardant) were assessed on Lilium. • BA and GA 3 at 50 mg l−1 significantly improve lily flower postharvest flower component including vase life. • Ancymidol at rate of 50 l−1 was effective in reducing stem elongation by 23 % to 41 % without adverse side effects on leaf and flower postharvest quality. • Ethephon successfully reduced stem length (28 %-53 %) and resulted in 67 % to 100 % flower abortion across lily cultivars. Plant growth regulators (PGRs) are chemical compounds that can potentially stimulate cut flowers growth and development and play key regulatory roles in plant responses to the surrounding environment. The aim of this study was to assess how the application of five PGRs; 6-Benzylaminopurine (BA, cytokinins), indole-3-acetic acid (IAA, auxins), gibberellic acid (GA 3 , Gibberellins), Ethephon (ethylene stimulant, stem retardant) and Ancymidol (stem retardant) affected plant morpho-physiology, leaf and stem anatomy, yield and flower quality of lily (Lilium × elegans cvs. MayTime and Fangio). Two experiments were carried out; in the first experiment, PGR stimulants (BA, IAA, GA 3) were applied at rates of 50 and 200 mg l−1 on days 30 and 40 (vegetative stage). The results showed that BA and GA 3 at 50 mg l−1 significantly increased leaf area in 'Fangio' by 44 %-69 %. In addition, BA, IAA and GA 3 at lower rate (50 mg l−1) significantly increased flower number per stem ('Fangio' 29 %-47 %; 'Maytime' 20 %-70 %), and vase life ('Fangio', 16 %-32 %; 'Maytime' 17 %-18 %). In terms of anatomy, BA at both rates (50 and 200 mg l−1) increased leaf thickness while GA 3 at 50 mg l−1 increased the total number of vascular bundles in the stem, compared to control untreated ones. The cultivar 'Maytime' had higher leaf area (200 %), plant height (73 %), number of days to flowering (49 %), brightness or lightness color L* (106 %), lower number of flowers per stem (43 %), and shorter vase life (21 %) than 'Fangio'. In the second experiment, both lily cultivars received two foliar sprays of growth retardants; Ancymidol at rates of 50 and 200 mg l−1 and Ethephon at 50 and 500 mg l−1. Ancymidol at 50 mg l−1 was effective in reducing stem elongation by 23 % to 41 % without adverse side effects on leaf and flower quality. In fact, lilies plants treated with Ancymidol at 50 mg l−1 had similar leaf area, chlorophyll content, photosynthesis rate, stomatal conductance, transpiration, flower diameter, number per stem and vase life to that of control non-treated plants. On the other hand, reduced stem length (28 %-53 %) resulted from Ethephon application was associated with 67 % to 100 % flower abortion across lily cultivars. Overall, this study revealed that foliar application of PGRs (BA, GA 3 and IAA) at a rate of 50 mg l−1 hold promise for improving flower quality of lily cultivars, specifically, flower numbers per stem and vase life. In addition, 50 mg l−1 of Ancymidol is efficient in producing compact plants while maintaining leaf and flower quality components. [ABSTRACT FROM AUTHOR]

The present research investigated the impact of plant growth regulators in mitigating the effects of heat stress in tomato (Solanum lycopersicuwi L.) genotype LST-6 and cultivar Punjab Varkha Bahar-4. In north India, the temperature in the summer season ranges between 25-45 °C and temperature above 28 °C leads to heat stress in plants and negatively affects the reproductive stage of plants. Considering this, we subjected the plants to varying concentrations of GA3 (10, 20, 30 µg/mL) and 4-CPA (15, 45, 75 µg/mL). GA3 application took place three weeks after transplanting, while 4-CPA was administered during the anthesis stage. We recorded observations from both control and treated plants, with a 10-day gap between each spray treatment. The application of plant growth regulators (PGRs) enhanced the plants' ability to withstand high temperatures by improving photosynthetic efficiency, as evidenced by increased chlorophyll and carotenoid levels in the leaves. The level of different biochemical constituents (total protein, starch, total soluble sugars, phenol and proline content) also increased in PGRs treated plants. Application of GA3 and 4-CPA also enhanced the membrane thermostability and reduced lipid peroxidation. The PGRs treated plants exhibited increased plant height, leaf area, pollen viability, fruit set, number of fruits per plant and fruit weight, ultimately improving yield. GA3 and 4-CPA application also increased the total soluble solids, lycopene content and titratable acidity in tomato fruits. Thus, overall improvement was observed with the application of PGRs; however, 75µg /mL 4-CPA was most effective in imparting thermo tolerance. [ABSTRACT FROM AUTHOR]

The use of plant growth regulators has led to environmental contamination of water bodies that occur adjacent to agricultural areas. Some of these chemicals are bioactive, not only to plants, but also to non-target exposed biota, namely of the aquatic compartment. Previous work demonstrated the establishment of hepato- and nephrotoxic effects in juvenile tilapia (Oreochromis niloticus) exposed via aquatic media to gibberellic acid (GA3), which is among the most used plant growth regulators, in agricultural practices. Here, we investigated the effect of GA3 on hematological indices, poikilocytosis, nuclear abnormalities, and genotoxic indices measured in Nile tilapia (Oreochromis niloticus), as well as the putative protective effects of dietary supplementation of Spirulina (Arthrospira platensis). Fish were evenly assorted into 5 groups: group I served as a control, and groups II–V were fed diets supplemented with Spirulina at rates of 0 g/kg, 5 g/kg, 20 g/kg, and 100 g/kg, respectively, for 2 months before being exposed to 150 mg/L GA3. The results revealed that GA3 exposure decreased significantly all hematological indices (P < 0.05), except leucocytes and mean corpuscular hemoglobin concentration (MCHC), compared to the control group (P > 0.05). GA3 exposure increased significantly the percentage of nuclear abnormalities, altered erythrocytes and the percentages of tail DNA, compared to the control group (P < 0.05). Spirulina supplementation restored the hematological, poikilocytosis, nuclear abnormalities, and the percentages of tail DNA to near normal levels. The 100 g/kg SP treatment was the most effective in attaining such effect, showing concentration-dependency. The present study reinforces our findings of the toxicity of GA3 on O. niloticus and suggests that the addition of Spirulina to fish diet can mitigate the hemotoxic effects of GA3. [ABSTRACT FROM AUTHOR]

An investigation was carried out at Department of Floriculture and Landscape Architecture, College of Agriculture Vellanikkara to evaluate the effects of growth regulators and pruning on induction of off-season flowering in jasmine (Jasminum sambac L.). The experiment was laid out in randomized block design (with two factors) viz. time of pruning (factor 1) - last week of September, last week of October and last week of November, and application of growth regulators (factor 2) such as cycocel (1000 ppm, 1500 ppm), paclobutrazol (200 ppm, 300 ppm), mepiquat chloride (150 ppm, 300 ppm) GA3 (100 ppm, 150 ppm), with two replications. In the present study, P x G interaction had a significant effect on the days to bud initiation, number of cymes per plant and number of buds per plant. The treatment combination P1 x G1 (pruning during last week of September along with application of cycocel 1000 ppm) was found to give better flower yield during offseason. [ABSTRACT FROM AUTHOR]

The objective was to study the effectiveness of the growth regulator (ANA + GA3) associated or not to the application of adjuvant and artificial pollination in 'Gefner' atemoya. The experiment was conducted in the experimental orchard at Florida's Tropical Research and Education Center. The experimental design was in a randomized block, with 14 treatments, 10 repetitions and 3 flowers per plot. The highest percentages of fixed fruits were obtained with hand pollination - HP and 450 NAA + 1250 GA3 mg L-1 + adjuvant and HP. The use of hand pollination for 'Gefner' atemoya tree proved to be the most efficient method so far. Applying growth regulator without artificial pollination produces parthenocarpic fruits, however with high rate of abortions, and small fruits. Growth regulators together with hand pollination produces small and uneven fruits, and cause reduction in the fruits' titratable acidity. The use of adjuvant caused low fixation and toxicity to fruits, and its use is not recommended. [ABSTRACT FROM AUTHOR]

The seeds of mustard variety of Brassica junncea PR-15 were imbibed in the water for 6-hrs. and then seeds were washed by distilled water and grown in the petridishes under UV-B exposure, alone and along with different growth regulators such as IAA (10-7), Kn (10-5) and GA3 (10-7) M (molarities) concentrations were noted during laboratory studies. The seed germination and seedling growth of the Brassica juuncea PR-15 (Rai) were observed for different concentrations of PGRs, alone and along with UV-B exposure for studies of chlorophyll estimation to & evaluated the appropriate concentrations of these growth regulators, which applied in field studies for the chlorophyll analysis. [ABSTRACT FROM AUTHOR]

Plant growth regulators (PGRs), such as cytokinins (6-benzyladenine; BA) and gibberellins (GAs), are widely used in fruit production. This study focused on the plum cultivar "Čačanska rodna" (P. domestica L.) grafted on vegetative rootstock "WaVit" and generative rootstock Prunus cerasifera, with interstock Prunus spinosa. PGR treatments included 50 mg L−1 and 100 mg L−1 of BA and 200 mg L−1 of gibberellin A3 (GA3) and non-treated control. Pomological characteristics of plum fruits were examined at harvest, while physicochemical properties were analyzed at harvest and after 28 days of cold storage and 4 days of shelf life. GA3 and BA application changed the fruit morphological traits, improved skin strength, and increased carotenoid, anthocyanin and sucrose content while decreasing the titratable acidity at harvest. The beneficial effects of higher sucrose, anthocyanin and carotenoid levels persisted in all PGR-treated fruits after cold storage and shelf life. GA3-treated fruits had firmer flesh, stronger skin and higher total soluble solids (TSS) content, while in BA-treated plums, these effects were rootstock-dependent. The physical properties and chemical composition of plum fruit in the postharvest period suggest beneficial effects of the applied PGR treatments. Moreover, these chemical treatments might have prolonged the beneficial impact on fruit storability, nutritional profile and sensory properties. Based on our results, GA3 preharvest treatment can be included in standard cultivation practices within contemporary production systems of European plums not only to improve fruit quality at harvest but also to improve the storage potential and nutritional value, regardless of the rootstock used. [ABSTRACT FROM AUTHOR]

The mango is considered as 'king of fruits' in India due to its delicious taste and nutritional status. Extension of fruit shelf life is a prime importance for availability of fresh fruit in market for longer duration and distance transportation. India is the largest producer and a prominent exporter of mango in the world.In this context, the study was conducted to evaluate the effect of preharvest spray of different chemicals and plant growth regulators (PGRs) on mango var. 'Amrapali' for shelf life and its quality. As 'Amrapali' has regular bearer with very good flavor and taste with a late maturing character, selected for shelf life studies. The fruits of mango weresprayed with chemicals viz. CaCl2 1%, CaCl2 2%, Ca(NO3)2 1%, Ca(NO3)2 2%, KNO3 1%, KNO3 2%, GA3 25 mg/l, GA3 50 mg/l, Ethrel 0.1 ml/l and Ethrel 0.2 ml/l prior to harvest. After harvesting, fruits were stored under ambient storage condition. Among all the treatments, GA3 25 mg/l treatment recorded significantly highest fruit length, fruit diameter, fruit volume and fruit weight at harvest and at fully ripe stage. Application of CaCl2 2% resulted in significantly minimum physiological loss in weight consistently from 2nd day to 16th day of storage besides significantly highest shelf life and quality. Hence, this intervention can contribute in preserving physical and chemical quality attributes for maximum acceptance by consumers. [ABSTRACT FROM AUTHOR]

A field experiment was carried out to evaluate the effect of plant growth regulators i.e., cycocel, NAA, GA3 at Vegetable research farm of Lovely Professional University, Phagwara (Punjab) during year 2018. The trial was conducted with seven treatments (Including control) and replications thrice. Plants treated with GA3 @20ppm resulted in maximum growth characters like as vine length and leaves per plant whereas plant treated with GA3@40 ppm showed maximum number of branches and number of female flowers. Maximum number of fruits per plant and yield was recorded in GA3 @40 ppm, while maximum fruit length and diameter of fruits was registered with GA3 @ 40ppm and NAA @100ppm, respectively. Among all treatments lower plant growth and yield was found in plants treated with water spray (control). [ABSTRACT FROM AUTHOR]

Plant growth regulators (PGRs) have been considered as agrochemicals applied widely in agricultural production, wherein, gibberelic acid (GA3) has gained an interest in using to enhance the growth and improve yield for various vegetables. In this work, lettuces were sprayed with GA3 at different concentration of 0, 10, 30, 50 and 100 mg L-1, respectively, at three dates after transplanting (the 7-day, the 14-day, and the 21-day). The impacts of GA3 on the growth, nutrient elements, and the absorption of heavy metals in lettuces were investigated. The accumulation of GA3 by lettuce plants were confirmed by liquid chromatography - tandem mass spectrometer system (LC-ESI-MS/MS). The results demonstrated, that low concentrations of GA3 (10 and 30 mg L-1) increased the plant height, number of leaves and fresh weight of lettuces, whereas the opposite results were reported in high concentration of GA3 treatment (100 mg L-1). In addition, GA3 decreased nutrient contents of Fe and Mn, and heavy metals' absorption in lettuces. However, the higher concentrations of GA3 treatment use, the more their accumulations were found in lettuce samples. To the best of our knowledge, this is the first investigation of the influences of GA3 on nutrient elements and the absorption of heavy metals in lettuce. This is needed to further investigate the improvement of crop production efficiency with PGRs, and to minimize their harmful impact on human health and the ecological environment. [ABSTRACT FROM AUTHOR]

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Field experiments were conducted with four levels of seed priming including control and two varieties of pigeon pea at ICAR-Indian Institute of Seed Science, Mau during three consecutive years (2011-12 to 2013-14). One-year-old seeds of pigeon pea varieties (Bahar and Malviya-13) were primed with growth regulator (100 ppm GA3), in-organic salt (0.2% KNO3) and tap water (sanitized) separately for 06 hrs. and sown in field under RBD with 03 replications. Observations were recorded on seed quality parameters, biochemical attributes including nitrate assimilatory enzymes and activities of anti-oxidant enzymes during seedling stage. Seed quality parameters including germination, seedling growth and vigor indices were significantly enhanced through seed priming with GA3 followed by KNO3 and tap water over unprimed control. Biochemical attributes viz; chlorophyll a andb contents, were more influenced with GA3 priming followed by KNO3 and tap water whereas the proline accumulation was reduced with priming treatments and maximum reduction was noted with GA3 followed by KNO3 and tap water. Enhancement in nitrate assimilatory enzymes including nitrate and nitrite reductase activities was more with KNO3 priming followed by GA3 and tap water. Anti-oxidant enzymes activities including Catalase, Peroxidase and Super Oxide Dismutase were also increased significantly by KNO3 priming followed by GA3 and tap water over unprimed control. [ABSTRACT FROM AUTHOR]

Soil pollution due to potentially toxic elements is a worldwide challenge for health and food security. Chelate-assisted phytoextraction along with the application of plant growth regulators (PGRs) could increase the phytoremediation efficiency of metal-contaminated soils. The present study was conducted to investigate the effect of different PGRs [Gibberellic acid (GA3) and indole acetic acid (IAA)] and synthetic chelator (EDTA) on growth parameters and Cd phytoextraction potential of Dysphania ambrosioides (L.) Mosyakin & Clemants grown under Cd-spiked soil. GA3 (10−7 M) and IAA (10−5 M) were applied four times with an interval of 10 days through a foliar spray, while EDTA (40 mg kg−1 soil) was once added to the soil. The results showed that Cd stress significantly decreased fresh biomass, dry biomass, total water contents, and photosynthetic pigments as compared to control. Application of PGRs significantly enhanced plant growth and Cd phytoextraction. The combined application of GA3 and IAA with EDTA significantly increased Cd accumulation (6.72 mg pot−1 dry biomass) and bioconcentration factor (15.21) as compared to C1 (Cd only). The same treatment significantly increased chlorophyll, proline, phenolic contents, and antioxidant activities (CAT, SOD, and POD) while MDA contents were reduced. In roots, Cd accumulation showed a statistically significant and positive correlation with proline, phenolics, fresh biomass, and dry biomass. Similarly, Cd accumulation showed a positive correlation with antioxidant enzyme activities in leaves. D. ambrosioides showed hyperaccumulation potential for Cd, based on bioconcentration factor (BCF) > 1. In conclusion, exogenous application of GA3 and IAA reduces Cd stress while EDTA application enhances Cd phytoextraction and ultimately the phytoremediation potential of D. ambrosioides. [ABSTRACT FROM AUTHOR]

Background: The South Gujarat hilly part is considered to be a non-traditional area of strawberry cultivation in India. The poor farmers of this region are cultivating strawberries under open field condition. Both, the yield and quality of strawberry fruits of this region are not up-to-the-mark as there in other parts of the country. Hence, a low-cost improved production technology is required to maximize yield as well as improve the quality of strawberry fruits. Methods: Uniform runners of strawberry cv. Winter Dawn were grown in open field under paddy straw as bedding material. Foliar spraying of plant growth regulators viz. NAA (50, 75, 100 and 125 mg l -1) and GA3 (50, 75, 100 and 125 mg l -1) were done at 30 and 60 days after planting. The experiment was laid out in randomized block design with control plants receiving no spray treatments and replicated thrice. Result: The plant growth parameters like plant spread, number of leaves, number of crowns, leaf area, length of petiole, number of runners were recorded maximum with the application of 100 mg l -1 GA3. This treatment was also found to be the best in respect of number of flowers, number of fruits, fruit weight, marketable and total fruit yield of strawberry. Strawberry fruits with the highest total soluble solid, ascorbic acid, reducing sugar, non-reducing sugar and total sugar content were recorded in the plants which received 125 mg l-1 NAA. However, the plant growth regulator treatments failed to influence any significant effect on days taken to 50.0 % flowering, fruit firmness and acidity content of strawberry fruits. [ABSTRACT FROM AUTHOR]

The efficacy of plant growth regulators (PGRs) has been demonstrated in the flowering of economically significant orchid hybrids, but studies of their effects in wild species with commercial potential are scarce. The effect of three doses of gibberellic acid (GA3) and 6-benzyladenine (BA), individually or in combination, and a control without PGRs, were evaluated during three flowering periods in Laelia anceps subsp. anceps, in the temporal behavior of flowering, morpho-floral quality parameters and in potential residual effects and malformations. Significant effects were observed between the experimental periods and doses used, with a single application of PGRs in the first period reducing the days to visible flower induction (DVFI), days to anthesis (DAN) and days of flower life (DFL), mainly in the first period. There were no significant differences between doses for morpho-floral quality parameters within each period, but differences existed between experimental periods, where the life and size of the flower increased in the first period, and the number of flowers and flower stems increased significantly in the second period. The doses of 2.37 mg · L−1 BA + 100 mg · L−1 GA3 showed highest significant consistency in the reduction of DVFI, DAN and increase of DFL and flower stems in the study. There were no floral malformations, and a positive residual effect was observed in temporal variables in the second period. Most of the doses used encourage beneficial effects in the various aspects of flowering evaluated. [ABSTRACT FROM AUTHOR]

Fruit splitting is one of main problems extensively observed in citrus-growing area located in the northern parts of Iran. In order to investigate the effect of 2,4-D and GA3 on incidence of fruit splitting in Thompson navel orange, an experiment, as a factorial arrangement in a randomized complete block design (RCBD) with three replications, was carried out in two consecutive years of 2016 and 2017. The main factors of this experiment included timing of spray at different growth stages (full bloom, petal fall, and June drop), 2, 4-D (0, 10, 20 mg L-1), and GA3 (0, 50, and 100 mg L-1). In the end of experiment, the characteristics including fruit length, fruit diameter, rind thickness, cellulase and polygalacturonase activities, total soluble solid, percentage of split fruit, and fruit yield were measured. Results showed that using 2, 4-D and GA3 not only decreased the rate of fruit splitting but also increased fruit yield as compared to controls. The highest fruit length, fruit diameter, rind thickness, total soluble solid and the lowest activities of cellulase and polygalacturonase were obtained using 100 mg L-1 GA3 and 20 mg L-1 2, 4 D during the full bloom. In general, the results revealed that using 2, 4-D and GA3 during the full bloom increased fruit yield while reduced fruit splitting and maintained the qualitative characteristics of Thompson navel orange. [ABSTRACT FROM AUTHOR]

Background: Pea is the most important crop and vegetable in the world but it has low yield. There is a need to find the ways for the improvement of crop productivity. Plant growth regulators (PGRs) are extensively used in many crops for enhancement of yield and quality. This study was designed to find the influence of PGRs on growth, yield and quality of pea cultivars grown in Pakistan. Methods: Pot experiments were conducted to evaluate the effect of various plant growth regulators (IAA, NAA and GA3) on pea during 2018-19. Four cultivars of pea i.e. Meteor, Green cross, Sultan and Dollar were used in these experiments. There were 0, 100 and 200 mmolL-1 levels for each hormone that were applied as foliar spray after 14 days of germination. Experiment was laid down in completely randomized design (CRD) with three replicates. Result: Morphological, biochemical and yield attributes significantly increased in four cultivars of pea except variety Sultan for few parameters. Cultivar Meteor showed highly positive increasing effects on growth and yield attributes as compared to other treatments. Catalases (CAT) activities were increased and peroxidase dismutase (POD) activities were reduced. It can be concluded that reduction in POD activities helped to increase the defense mechanism of plants and high CAT activities caused better balance in plant metabolism as a result growth, yield and quality of pea were increased. All the variables including shoot length, shoot biomass, number of fruits, total seed yield, carbohydrates and protein had positive correlation with phytohormones. These outcomes might be good indicators to predict the best pea cultivars that can have positive promising response for growth, yield and quality traits under plant growth regulators (PGR). [ABSTRACT FROM AUTHOR]

Ber (Ziziphus maurtiana) is an important minor fruit crop of India. Over the years the crop is now widely domesticated and commercial orchards of Ber are now available. With wide commercialization, many physiological problems, i.e. flowers and fruit drop, embryo abortion, poor flowering and fruit setting, abnormal and small size fruits etc. were observed which cause huge loss to the growers. In order to minimize these problems, over the years many experiments and advancement have been done, and among them, usage of plant growth regulators is one of the most adopted methods and is utilized to improve flowering fruiting and yield with improved fruit quality. The current review discusses the role of different plant growth regulators and how they influence each fruit character. This information could be useful to the researchers in planning further advance research in this aspect and for the commercial growers to decide the proper treatments to mitigate the problems. [ABSTRACT FROM AUTHOR]

The present study was carried out to evaluate the response of the anise plant seeds to the plant growth regulator gibberellin (GA3) and the effect of the saponins extract of Sansevieria hyacinthoides leaves on the seeds germination and seedling growth. Various plant extracts were used to improve crop yield and quality, being safe for the environment. Firstly, the toxic effect of the leaf extract was estimated using the phytotoxicity assay on radish seeds. This assay showed insignificant decrease in root length at 1000 µg/ml, whereas an increase in root growth was observed at concentrations 10 and 100 µg/ml. Similarly, stimulatory effect on the percentage of seeds germination was observed reached (100%) at 10µg/ml. Low concentrations (0.0, 1.25, 2.5, 5.0, 10.0 µg/ml) of saponin extract were applied to test the germination and growth of anise plant. Leaves extract increased the germination of anise seeds and enhanced the growth of root length significantly at 10µg/ml in comparison with control treatment (0µg/ml). The root lengths were 1.3 and 2.3cm after 4 and 7days respectively and the percent of germination reached 100% after only 7 days. The lower concentrations did not have any effect on seeds germination rate with little effect on root length. It is concluded that the saponins extracted from Sansevieria leaves are safe and has no toxic effect and possess clear activity similar to the effect of the plant growth regulator gibberellin on increasing seed germination rate and promoting seedling growth. [ABSTRACT FROM AUTHOR]

Potato (Solanum tuberosum L.) is an important food crop in Pakistan and produced twice or more in a year. Its tubers undergo a certain period of dormancy after the harvest and are incapable to sprout which can limit their usage as seed for the next season. Therefore, this study was planned to break the tuber dormancy using plant growth regulators and electric current. For this purpose, three experiments were conducted from April 2015 to July 2016 with the objectives: i) to screen out genotypes based on their dormancy duration and ii) to assess the effects of two dormancy breaking methods on seed tuber dormancy breakage, hydrogen peroxide contents and antioxidative activities at one and three week storage. The first experiment comprised of 22 equal number of white and red skin potato genotypes. Mean dormancy ranged from 36 to 85 days in these genotypes, including FD51-5 and PRI Red in short-term dormancy group; Sante and FD73-49 in medium-term dormancy group and FD69-1 and FD8-1 in long-term dormancy group. The second experiment consisted of above screened genotypes and three levels of benzyl aminopurine (30, 60 and 90 mgL-1) and gibberellic acid (10, 20 and 30 mgL-1). The solution of 60 mgL-1 benzyl aminopurine significantly reduced the dormancy duration in all genotypes but did not have a significant effect on the sprout outgrowth. While, 20 mgL-1 GA3 produced maximum sprout length with non-significant effect on dormancy duration. The genotype × PGR interaction was more pronounced in short and medium-term dormancy genotypes than in longterm dormancy genotypes. The third experiment also consisted of above six genotypes with five levels of electric current (0, 20, 40, 60 and 80 volt). The use of electric current was most effective at 80 volt for shortening tuber dormancy and inducing sprout length. Hydrogen peroxide contents, superoxide dismutase and ascorbate peroxidase activities after treatment with plant growth regulators and electric current increased with dormancy progression. In contrast, catalase and peroxidase activities decreased. Our results indicate that enhanced antioxidative activity is closely associated with the effect of applied treatments, storage period, genotypes and genotype × storage period. Nevertheless, further research should be continued to evaluate the combined effect of BAP and GA3 on dormancy termination. [ABSTRACT FROM AUTHOR]

Withania somnifera (L.) Dunal a member of the Solanaceae family, is a traditional medicinal plant commonly known in India as Ashwagandha. It is used for different diseases such as hiccup, cough, rheumatism, tuberculosis, and exhibits excellent antitumor and anti-bacterial activities as well. Direct organogenesis of plants using mature seeds provides faster response and is also a time saving approach, thus the present study was conducted to investigate the optimal concentrations and combinations of plant growth regulators with MS medium for the establishment of an efficient regeneration system in W. somnifera using mature seed as an explant. Therefore, an efficient in vitro protocol for high frequency regeneration has been developed using mature seeds as explant. In the present study, the multiple shoots along with embryogenic callus induction was best seen in MS medium supplemented with BAP (1.5 mg/L) and IAA (0.5 mg/L). Furthermore, MS medium fortified with GA3 (0.3 mg/L) and IBA (3.0 mg/L) alone was suited for shoot elongation and rhizogenesis respectively. The rooted plantlets were hardened and successfully established in the soil. The establishment of a highly reproducible regeneration system would greatly influence the efforts of improvement of the hereby studied medicinal plant species through useful gene transfer technology. [ABSTRACT FROM AUTHOR]

A field study was conducted to evaluate the effect of different plant growth regulators (PGRs) applied through seed priming and foliar spray on growth and yield of three okra cultivars grown under calcareous soils. The cultivars of Punjab Selection and Sabzpari produced significantly higher number of branches and leaves per plant, pod length and diameter and pod yield as compared to cv. Green ferry, while, cv. Punjab selection produced significantly greater number of flowers and pods per plant as compared to other two cultivars. Seed germination (%), plant height, and fruit set (%) were not affected by the cultivars. Among the PGR treatments, seed primed with GA3 resulted in significantly higher germination percentage and greater plant height at flowering. Seed priming and foliar spray with NAA and GA3 were effective in increasing the final plant height, number of branches, number of leaves, number of flowers and number of pods per plant and fruit set (%), fresh weight per pod and pod yield. However, pod diameter, pod moisture content and dry weight per pod were not influenced by the PGR treatments applied. These results suggested that the PGRs have great potential to improve seed germination, enhance growth and increase yield of okra cultivars under calcareous soils. [ABSTRACT FROM AUTHOR]

The present investigation were carried out at Experimental Farm of the Department of Agriculture, Mata Gujri College, Sri Fatehgarh Sahib, Punjab, India during the year 2019. The experiment comprised three treatments of plant growth regulators, (G0 = No growth regulator, G1= GA3 @ 50 ppm, G2= NAA @ 100 ppm) and four treatments of biofertilizers (B0= No biofertilizer, B1= Azotobacter @ 5 kg ha-1, B2= PSB @ 5 kg ha-1, B3= KSB @ 5 kg ha-1). Thus there were 12 treatment combinations replicated thrice in factorial randomized block design. Among plant growth regulators, maximum growth and yield parameters were observed in GA3 @ 50 ppm. Among the biofertilizers, B1= Azotobacter @ 5 kg ha-1 were recorded to be the best regarding growth and yield parameters. Maximum fruit yield was obtained in treatment combinations of G1 B1 - GA3 @ 50 ppm + Azotobacter @ 5 kg ha-1. [ABSTRACT FROM AUTHOR]

A field experiment was carried out during 2017-2018 in the Horticulture Research Station farm in El Kanater El Khayreia, El Kalubeia Governorate, Egypt, to find out the response of foliar application of melatonin, GA3 and NAA on vegetative and fruit attributes of 'Canino' apricot. Different plant growth regulators influenced all variable parameters related to vegetative growth and fruit. Results revealed that between all growth regulators, the foliar application of melatonin following by GA3 there was the highest vegetative growth as compared to other treatments, while GA3 gave the highest yield following by melatonin as compared to other treatments. Treatment with NAA improved vegetative growth, yield and fruit quality to a lesser extent as compared to the control. [ABSTRACT FROM AUTHOR]

The experiment was carried out to study the effect of organic practices, mulching and plant growth regulators on growth, yield and quality of papaya cv. Taiwan Red Lady 786 under subtropical conditions of Punjab. In this experiment, farmyard manure, vermicompost and mulching along with different concentrations of GA3, NAA and Ethrel were tested in randomized block design. Maximum plant height (145.33cm), stem diameter (37.66cm), number of leaves/plant (32.33), number of flowers (135.66/plant), number of fruits (40.66/plant), fruit set percentage (78.18%), fruit length (17.13cm), fruit breadth (12.23cm), specific gravity (0.92) and ascorbic acid percentage (83.77%) was recorded in GA3 200ppm with FYM, vermicompost and black mulching, whereas maximum TSS (16.71엯 B) and minimum acidity percentage (0.129%) was recorded with application of Ethrel 200ppm with FYM, vermicompost and black mulching. The results of this experiment revealed that integration of PGR's application with farmyard manure, vermicompost and black mulch yield better results. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Drought is one of the most serious environmental factors limiting production of sugarcane worldwide. In order to assess the influence of gibberellins (GA3) on drought and plant growth, along with associated physio‐biochemical attributes, expression of eight drought‐responsive genes were quantified and analysed.At grand growth stage (120 DAP) two sugarcane varieties (CoLk94184, CoPK05191) were exposed to drought by withholding irrigation. GA3 (35 ppm) was applied using battery‐operated uniform controlled dispensing sprayer twice at 1‐week intervals on 2‐week drought‐stressed plants. Physio‐biochemical attributes including antioxidant enzyme activities were estimated following standard protocols. RT‐PCR was performed to visualise the drought‐associated gene expression patterns.Drought triggered a reduction in RWC and chlorophyll content but these recovered when droughted plants were exposed to GA3. Proline content increased many fold in both varieties under stress, but decreased under the influence of GA3. There was a mixed response of antioxidant enzyme activity, which distinctly declined after GA3 exposure, together with a lesser reduction in dry matter content over that of control plants. With increasing stress, expression of pyrroline‐5‐carboxylase synthetase (P5CS) and betaine‐aldehyde dehydrogenase genes was observed, selectively up‐regulated in CoPK05191. Expression of proline oxidase/transporter was high in CoPK05191 but diminished along with proline content after exposure to GA3. CoLk94184 showed no significant difference in P5CS gene expression under stress condition, whereas expression of betaine‐aldehyde dehydrogenase gene was unchanged in response to stress.Results demonstrated that exposure of droughted plants to GA3 not only led to recovery of activity of drought‐associated physio‐biochemical attributes, but also minimised impact on cane dry weight and quality. Further, GA3 application caused differential gene expression that possibly triggers increased responsiveness towards drought tolerance in sugarcane. [ABSTRACT FROM AUTHOR]

An experiment was conducted to investigate the effects of growth regulators on growth, yield and the quality of okra. Indole Acetic Acid (IAA) and Gibberellin (GA3) were applied as foliar spray and stem and flower injection at concentrations of 0, 30, 60, 90, and 120 mg/L on okra plants. The results showed that foliar spray of 90 mg/L IAA, increased the number of leaves, number of branches, number of flowers and number of pods. On the other hand, spraying of 90 mg/L GA3 increased stomatal conductance and pod weight of okra, while the highest chlorophyll content was recorded with 60 mg/L GA3. Stem injection of 120 mg/L IAA produced the highest number of leaves, number of branches, number of flowers, number of pods and plant height. Similarly, 120 mg/L GA3 as stem injection increased the number of branches, number of leaves, number of flowers and number of pods and total soluble solids (TSS). Flower injection of IAA at 30 and 90 mg/L increased pod size, pod weight, pod number and TSS content, while seed production was inhibited by 120 mg/L IAA. GA3 used in a 90 mg/L treatment as flower injection increased pod size and TSS content. It is concluded that the application of 120 mg/L IAA and 90 mg/L GA3 increased the growth, development and quality of the okra fruit and stem and that flower injection worked better than foliar spray. [ABSTRACT FROM AUTHOR]

A field trial was conducted during 2015 and 2016, to study the effect ofgrowth regulators on growth, flowering, yield and fruit quality of strawberry cv. Chandler. The experiment was laid out in completely randomized design with 16 treatments viz.CPPU at 1, 2 and 4 ppm, GA3 at 25, 50 and 75 ppm, Promalin at 2, 4 and 6 ppm, GA4+7 at 5, 10 and15 ppm, NAA at 10, 20 and 30 ppm and control (water spray) and each treatment was replicated thrice. The results revealed that the plants sprayed with 15 ppm GA4+7 two weeks before flowering significantly reported highest plant height (33.43 cm), leaf area (239.70 cm2), number of flowers (31.94), fruit set (87.45 %), number of fruits per plant (29.02), yield (540.01 g/plant), fruit length (53.63 mm) and fruit diameter (37.19 mm) and fruit weight (23.70 g) as compared to control. This treatment resulted in 196.36 % increase in yield and 56.22 %in fruit weight over control. Plants sprayed with 6 ppm promalin also showed significant improvement in vegetative growth, fruit size, yield and fruit quality, which resulted in 137.92 % increase in yield and 51.81 % increase in fruit weight over control. Hence, it is concluded that foliar spray of 15 ppm GA4+7 applied 2 weeks before flowering is beneficial in improving growth, yield and fruit quality of strawberry plants. [ABSTRACT FROM AUTHOR]

The use of plant growth regulators has become a widespread practice in the citrus producing countries of the world to control fruit drop at various stages during fruit growth and development. An experiment was conducted to evaluate the effects of two plant growth regulators on reproductive growth and yield development of Assam lemon (Citrus limon L.). Foliar applications of different concentrations of GA3 (20, 40 and 60 ppm) and NAA (10, 20 and 30 ppm) at pre- and post-flowering stages significantly altered reproductive physiology of the crop. GA3 appreciably reduced the time taken for flower initiation compared to control. The duration from flowering to harvest also decreased significantly by GA3. Yield and yield attributing characters like number of flowers per shoot, highest fruit set, fruit retention and number of fruits per plant were also positively influenced by GA3 treatment. The highest yield (55.92 t/ha) was recorded in GA3 (60 ppm) treated plants. [ABSTRACT FROM AUTHOR]

The experiment was carried out at HRS, Mondouri, BCKV during 2012-14 to find out the effect of growth regulators on growth and yield of chilli cv. Beldanga. Three concentrations of four growth regulators, namely, NAA (25, 50 and 75 ppm), GA3 (20, 40 and 60 ppm), 2, 4-D (5, 7.5 and 10 ppm) and ethrel (300, 400 and 500 ppm) were included in this investigation. The regulators were applied as foliar spray at 30 and 60 days after transplanting. There were altogether 13 treatments including control (water spray).In both the years, the seedlings were transplanted during middle of November in 2 x 1.6 m plot at 50 x 40 cm spacing accommodating 16 plants per plot. The experiment was laid out in RBD with three replications. The NPK dose was 150 : 80 : 80 kg/ha. Among different treatments, maximum number of both primary (4.43) and secondary branches (17.97), 1000-seed weight (3.74 g), yield per plant (182.31 g) and projected yield per hectare (6.37 t) were observed in plants raised from application of NAA 75 ppm. Maximum plant height (60.67cm), plant spread in (E-W) (36.00 cm) and maximum weight of 20 dry fruit (9.39 g) were recorded in GA3 60 ppm and GA3 20 ppm treated plants, respectively. The plant spread in (N-S) (36.97 cm) and maximum number of seeds per fruit (60.47) were recorded in 2,4-D 7.5 ppm treated plants. The projected yield under untreated control was 4.34 t/ha. From yield maximization point of view, the most effective treatment was NAA 75 ppm followed by NAA 50 ppm and GA3 60 ppm under alluvial plains of West Bengal for production of chilli. [ABSTRACT FROM AUTHOR]

This study was carried out during 2013 and 2014 seasons to examine the impact of spraying clusters of European grapevine cv. Early Sweet once when average diameter of berries reached 6 mm with GA3 at 10 to 40 ppm or S1tofex at 2.5 to 10 ppm on yield and fruit quality. Spraying clusters with GA3 or Stiofex was effective in improving yield, cluster and berry weight, dimension, total acidity %, protein %, P, K, and Mg in the juice and decreasing shot berries o/o, T.S.S. %, reducing sugars %, T.S.S./ ac1d and total carotenoids relative to control treatment. All GA3 and Sitofex treatments materially delayed date of harvesting and had no effect on berry shape index. The effect either in decrease or increase were associated with increasing concentrations of each growth regulator without substantial differences on the aforementioned characteristics among the higher two concentrations of each auxin. In most cases the uppermost effects were attributed to using GA3 For promoting yield, fruit quality and nutritional value as well as overcommg the problem bemes of Ely Sweet grapes grown under Minia region, it is advised to spray the whole clusters once at 6 mm bernes d1ameter stage w1th GA3 at 20 ppm. [ABSTRACT FROM AUTHOR]

A field experiment was conducted to study the effect of plant bio regulators on growth, flowering and seed yield in China aster cv. Kamini at College of Horticulture, Rajendranagar, Hyderabad during rabi, 2013-14. The experiment was laid in randomized block design and replicated twice. Plant growth regulators viz., GA3 salicylic acid, maleic hydrazide, alar and paclobutrazol were used in the experiment. The treatments were imposed as foliar sprays twice at 20 and 35 days after transplanting. The observations on growth parameters were recorded at three stages of plant growth viz., 30, 60 and 90 DAT. GA3 200 mg/1 spray recorded significantly higher plant height (60.10 cm), number of primary branches per plant (24.60) and number of secondary branches per plant (61.45) at 90 DAT, number of flower's per plant (84.96), flower yield per plan t (109.66 g), flower yield per hectare (16.58 t), seed yield per plant (9.98 g), seed yield per ha (1509.31 kg) and 1000 seed weight (2.01 g). GA3 200 mg/1 foliar spray was found to bet par with SA 200 mg/1 in respect of number of primary branches (23.86), flower yield per hectare (15.90 t), seed yield per plant (9.85 g) and seed yield per hectare (1489.65 kg). SA 200 mg/1 foliar spray could be recommended for increased growth, flower and seed yield in China aster cv. Kamini as it is more cheaper than GA3 [ABSTRACT FROM AUTHOR]

This investigation was carried out at the orchard of Faculty of Agriculture, Assuit University during 2012 and 2013 seasons with the objectives of: study the rules and the effects of some plant growth regulators (PGRs) namely gibberellic acid (GA3), benzyl amino-purine (BA), and naphthalene acetic acid (NAA) on the developmental changes on some physical properties as well as fruit ripening of Abbodi and Abiad Aswan fig fruits during its growth. Twelve trees (4 treatments x 3 replication) of both cvs. were used for this study. The PGRs were sprayed at the end of the first period of fruit growth. The result of this study could be summarized as follows: -The fruit diameter of untreated fruits (control) significantly and very rapid increased during the first period (6 weeks) followed by slow increase for about 4 weeks (period II) and then it was rapidly increased again at the third period and took 7 weeks until maturity. -Concerning the effect of the applied growth regulators on the diameter of fig fruits, it was found that, GA3 at 50 ppm and NAA at 25 ppm significantly increased the fruit diameter as compared with BA treatment at 40 ppm and untreated fruits during all developmental stages. While, the treated fruits with the three growth regulators had significantly smaller diameter comparing with untreated one at the maturity stage in both experimental seasons. -The fruit weight and volume of both cultivars took approximately the same trend as diameter concerning the response of applied growth regulators during both studied seasons. -GA3 treatment advanced fruit maturity by 4 weeks, on Abiad Aswan and 3 weeks on Abbodi cv. while NAA enhanced fruit maturity of Abiad Aswan cv. by 3 weeks and one week for Abbodi cv. earlier than the control. Concerning BA treatment, it advanced fruit maturity by 2 weeks for Abiad Aswan cv. and one week for Abbodi cv. during the two experimental season. [ABSTRACT FROM AUTHOR]

The experiment was conducted to determine the most effective PGRs for the optimum performance of chickpea cultivars and to select the most promising cultivar. The PGRs were IAA, GA, Kn, SA and Tria and the cultivars were DCP 92-3, GNG-469, KWR-108 and H1. Crop characters like shoot, root length, leaves number, number of pods per plant, 100-seed weight, seed yield and seed protein content were influenced by applied PGRs but most significantly with GA. The effect of spray of PGRs on seed protein content and also cultivar differences were found significant. Cultivar, DCP 92-3 gave the maximum seed yield which was 59.60% more over H 1, produced the lowest value and it was followed by KWR-108. Among the applied PGRs, GA produced the 174.48% higher seed yield than control, and this effect of GA was equalled by that of SA. The effect of interaction treatments was, found non-significant for seed yield. [ABSTRACT FROM AUTHOR]

• Hand pollination showed fruits of larger sizes and excellent organoleptic qualities. • The use of growth regulators showed smaller fruits, but of excellent organoleptic quality. • The adjuvant at the dosage applied resulted in peel toxicity and is not recommended. The objective of this study was to evaluate the effect of GA 3 and NAA plant growth regulators, LI 700® adjuvant and hand pollination on fruit set and quality of 'LeahReese' sugar apple under subtropical conditions. The randomized block design had 14 treatments, 10 replicates and 3 flowers per treatment per tree. For quality evaluation, 9 fruits from each treatment were used, with 3 replicates and 3 fruits per replicate. The treatments were combined using growth regulators, adjuvant, and hand pollination. The regulators were NAA (0 and 450 mg L−1), GA 3 (0; 750; 1000; 1250 and 1500 mg L−1), with or without application of adjutant (LI700®) and with or without hand pollination. The solutions were applied directly to the flowers at anthesis (female stage) and repeated to the fruits at 7 and 21 days after the anthesis. The percentage of fruit set was evaluated bi-weekly. After the harvest, the physical and physical-chemical characteristics of the fruits were evaluated. The variables evaluated were submitted to ANOVA and the effects of the treatments were separated by the Tukey test, at 5% probability level. The percentage of fruit set decreased by the 7th week in all treatments. Only one treatment (T13) without hand pollination set parthenocarpic fruit. The application of growth regulators to hand pollinated flowers resulted in fruits with good physicochemical qualities, but with lower quality physical characteristics than fruits obtained from hand only. The use of the LI 700® adjuvant in the applied dosage caused peel damage to sugar apple. [ABSTRACT FROM AUTHOR]