Paclobutrazol Application Research Articles

An overview of gibberellin inhibitors for regulating vegetable growth and development

Gibberellin (GAs) promotes plant growth processes like germination, shoot elongation, root development, and flowering, while its inhibition is occasionally used in some vegetable crop practices. This paper aims to review the current literature on GAs inhibitors in practical vegetable crops and suggest future strategies for increasing yield. In some vegetable crops, inhibiting GAs with natural (abscisic acid, ethylene) or synthetic (paclobutrazol, prohexadione-Ca) regulators is key to improving yield and quality. Abscisic acid (ABA) counteracts GAs in germination and stress adaptation, while ethylene (ET) opposes GAs in senescence and growth inhibition. The application of paclobutrazol (PBZ) and prohexadione-Ca (Pro-Ca) is known to inhibit synthetic GAs, resulting in denser plants while improving plant photosynthetic efficiency, which improves crop yield. Achieving desired growth and yields with GAs inhibitors relies on precise dosing, emphasizing the importance of review studies for advancing vegetable cultivation.

The Effect of Soil Application and Foliar Sprays of Paclobutrazol at Various Concentrations on the Plant Morphology of Lime var. (Citrus aurantifolia L)

The experiment was conducted with the view to study the effect of soil application and foliar sprays of paclobutrazol at various concentrations on the plant morphology of lime var. The soil of experimental site was sandy loam in texture with pH of 6.8. The experiment was CRD and two factorials, Complete Randomized Design, with four different doses of foliar sprays and five different doses of soil application of paclobutrazol. Trunk diameter growth was found highest (46.23 cm) with soil application of paclobutrazol at 2.0 ml/L of water. Floral shoots percentage was found highest (93.50%) with soil application of paclobutrazol at 1.0 ml/L of water. Highest average leaf area of (8.70 cm2) was found with soil application of paclobutrazol at 4.0 ml/L of water. Nevertheless, it is recommended for future study to conduct the experiment with soil application of paclobutrazol at 2.00 ml/L with different planting densities.

Response of potato tuber as an effect of the N-fertilizer and paclobutrazol application in medium altitude

Abstract Development of G0 potato seeds in medium altitude with high temperatures has been constrained high temperatures, which inhibited plant growth and development, especially for tuber formation. The production of G0 potato seeds in the high-temperature area can be increased by the application of nitrogen (N) fertilizer and paclobutrazol (PBZ). The study aimed to identify the effect of different doses of N-fertilizer and the frequency of PBZ application on the plant growth and yield of first-generation potato seeds (G0) in medium land. The Randomized Complete Block Design with two factors was used in this experiment. The first factor was the dose of N-fertilizer (n 1 = 60, n 2 = 120, and n 3 = 180 kg/ha) and the second factor was the frequency of PBZ application (p 1 = 1, p 2 = 2, and p 3 = 3 times), applied starting at 40 DAP and repeated every 10 days with a concentration of 100 ppm. The results showed that there was a significant interaction between the dose of N-fertilizer and the frequency of PBZ application on plant dry weight. The 120 kg/ha of N-fertilizer-treated plants exhibited the highest plant height and the number of stolons per plant, whereas three times PBZ application treated plant exhibited the higher tuber growth rate, the number, and weight of tuber per plant with the value of number and weight of tuber per plant of 9.26 and 83.97 g, respectively. It can be concluded that N-fertilizer increased plant growth, whereas PBZ increased G0 potato seeds in the medium land altitude with high temperature.

Effect of Paclobutrazol on Biochemical and Yield Attributes of Chickpea (Cicer arietinum L.)

The experiment was carried out during the rabi (winter) season ( 2nd week of November to last week of Feburary) of 2019 and 2020 at the District Seed Farm, ‘AB’ block, Kalyani at Bidhan Chandra Krishi Viswavidyalaya, Nadia, West Bengal to study the effect of paclobutrazol on the biochemical and yield attributes of chickpeas with yield. The experiment was laid down in a randomized block design having six treatments of a formulation of paclobutrazol 40% (0, 25, 35, 45, 55 and 65 ml ha-1) with each replicated four times and the experimental material for the study consisted of chickpea variety was JAKI 92-18. Results revealed that Paclobutrazol caused to decline in the leaf chlorophyll content and enhanced the accumulation of storage carbohydrates particularly starch in the leaf. Leaf soluble sugar content was lowest in the control (2.86) and all the treatments were significantly higher than the control in this respect. It caused to enhance the seed yield by enhancing the number of seeds plants-1 and improving the harvest index. The highest yield was obtained in paclobutrazol 35 ml ha-1 (2008 kg ha-1); other treatments with substantially higher yields than control were paclobutrazol 45 ml ha-1 (1783 kg ha-1), and paclobutrazol 25 ml ha-1 (1692 kg ha-1). Hence, foliar application of Paclobutrazol @ 35 ml l-1 may be most effective in augmenting the yield attributes and yield of chickpea during rabi season.

Influence of Low Concentration of Paclobutrazol and Its Application Close to the Main Trunk on Fruiting of Mango in Ultra High Density Plantations

Control of flowering and fruiting in mango is achieved by the application of Paclobutrazol (PBZ) in many commercial orchards. However, growers tend to use very high concentrations of the chemical, resulting in high costs of operation and long-term effects. This study examines the impact of low concentrations and varying application methods of PBZ on mango fruit yield in ultra-high-density plantations. Here 3 methods of application and 4 levels of PBZ concentrations (PBZ 23% SC) were tried in a 3 year study. Application of PBZ at N1 (close to the trunk, also termed as collar drench), N2 (20 cm away from the trunk) and N3, (1 m away from the trunk), all resulted in similar number of fruits and fruit weights. Using very low concentrations of PBZ, 4 (0.37 g a.i. /m canopy diameter (cd), 5 (0.46 g a.i. /m cd) and 6 (0.55 g a.i. /m cd) ml/2 liter water, it was found that the lowest 0.37 g a.i. /m cd is enough to get statistically higher fruit yield. These findings: a very low dose of PBZ can result in high productivity and a requirement of least volume of the solution when applied as a collar drench would make the use of PBZ more sustainable and encourage more growers to adopt the hormonal use for mango production.

Synergistic Effects of Seed Inoculation with Piriformospora indica and Foliar Hormonal Application on Early Flowering in Rice Bean (Vigna umbellata) Variety Surabhi

This study aimed to evaluate the effectiveness of seed inoculation with Piriformospora indica and various foliar hormonal treatments in promoting early flowering in fodder rice bean (Vigna umbellata Thunb.), variety Surabhi, conducted at the College of Agriculture, Vellayani. The experiment was laid out in randomized block design with ten treatments and three replications. The plot size of 3 m2 was followed in the field experiment. The experiment assessed the impact of different treatments on flowering and other biometric traits in the leguminous crop. The treatments included untreated control, seed inoculation with Piriformospora indica before sowing and foliar applications of salicylic acid (100 ppm,150 ppm), GA₃ (200 ppm,300 ppm), Paclobutrazol (10 ppm,20 ppm) and KNO₃ (1%,1.5%) at 30 days after sowing (DAS). The results revealed that significant differences were observed among treatments for all thirteen biometric traits measured. Early flowering was recorded in plants treated with salicylic acid @ 100 ppm(65.35 days), followed by GA₃ @ 300 ppm (67.72 days), salicylic acid @ 150 ppm (67.81 days), and Paclobutrazol @ 10 ppm (69.87 days), whereas the control flowered last (80.96 days. The findings suggest that the application of specific concentrations of growth regulators and seed inoculation with P.indica can effectively reduce the time to flowering, enhancing the potential for improved seed production in fodder rice bean.

UHPLC-MS/MS analysis of the influence of paclobutrazol application on Ophiopogon japonicus

The pharmacological effects of Ophiopogon japonicus are influenced by its active substances like saponins and flavonoids, which are crucial for assessing its quality. An ultra-high performance liquid chromatography tandem triple quadrupole mass spectrometry (UHPLC-MS/MS) method was developed for the qualitative and quantitative assessment of 20 saponins and flavonoids in O. japonicus. The average recovery of these compounds ranged from 70 % to 130 %, with relative standard deviations (RSD) between 0.11 % and 16.46 %. Planting O. japonicus in Santai County (Sichuan, China) and investigated the impact of 0.6, 1.3, 2.8, 5.6, and 11.3 g/L concentrations of paclobutrazol on both root yield and the levels of saponins and flavonoids in O. japonicus. Lower paclobutrazol concentrations (1.3 g/L) led to increased levels of saponins and flavonoids in O. japonicus such as ophiopogonin D′, ruscogenin and ophiopogonanone F, with paclobutrazol residues measuring 77.17 μg/kg DW. This preliminary insight into the influence of paclobutrazol and production of saponin flavonoids in O. japonicus bears significance for its larger industrial production.

Paclobutrazol application effects on green leaf index, morphology, and productivity of maize (Zea mays)

Abstract Indonesia’s growing demand for maize has necessitated the development of strategies to enhance crop yields. Paclobutrazol (PBZ), a growth regulator, presents a promising solution for improving plant growth and achieving crop production sustainability in maize. This study investigated the impact of various concentrations of PBZ on maize growth and yield. The study employed a single-factor randomized complete block design (RCBD), incorporating four treatments (0 ppm, 200 ppm, 400 ppm, and 600 ppm) and six replications. Data analysis employed Analysis of Variance (ANOVA) at the 5% significance level and followed by regression analysis. Results revealed significant effects of PBZ on agronomic and productivity variables in maize. Regression analysis demonstrated a linear correlation between PBZ and various parameters, including stem diameter, leaf area, leaf area index, plant dry weight, cob weight, and cob length. Furthermore, we identified a polynomial relationship between PBZ concentrations and both the green leaf index and corn-husk dry weight, with the optimal concentrations of PBZ are 567.5 ppm and 410.83 ppm, respectively. Additionally, various concentrations of PBZ showed a tendency for higher productivity at PBZ concentrations of 400 and 600 ppm. Therefore, 400 ppm became the lowest effective concentration of paclobutrazol for optimizing maize growth and yield.

Vegetative growth, flowering pattern and yield of mango (Mangifera indica L.) as affected by exogenous application of paclobutrazol and KNO3

Studied the response of different flowering regulatory agro-chemicals had a significantly positive impact on vegetative growth, flowering pattern and yield attributes of mango, during 2015-16 and 2016-17. Paclobutrazol is associated with a shorter internodal length and the highest flowering intensity. The study was laid out with 7 treatments in randomized block design and replicated thrice were applied on north Indian mango cultivars "Dashehari" and "Kesar" under the Banswara condition of Rajasthan. The results revealed that most of the flowering parameters were better performed with paclobutrazol @ 3.0 ml m-2 soil drench application mid-September (number of flowers/10 tagged panicle, per cent hermaphrodite flowers, per cent fruit set, least length and width of panicle) and foliar application of potassium nitrate 25 g l -1 observed maximum height and width of panicle, fruit weight, yield kg tree-1, yield t/ha.

Efficiency of paclobutrazol and gibberellic acid in wheat (Triticum aestivum L.) under different doses of nitrogen fertilization

Application of growth regulators like paclobutrazol and gibberellic acid is a suitable way to prevent excessive nitrogen consumption. Therefore, this 2-year research was conducted in Karaj, Iran. This research was laid out in a randomized complete block design with three replications in a split-plot arrangement in 2019–2021. Treatments included nitrogen at three levels: (60, 105 and 150 kg ha−1) which were placed in the main plots. The second factor was the foliar application of growth regulators at three levels: [gibberellic acid (100 ppm), paclobutrazol (200 ppm) and control]. The results showed that application of paclobutrazol and gibberellic acid raised super wheat yield and quality compared to control. The highest biological yield (27.67 ton ha−1), was observed in the interaction of nitrogen 150 kg ha−1 + gibberellic acid in the second year, which was the same with nitrogen 150 kg ha−1 + gibberellic acid in the first year and also interaction of nitrogen 150 kg ha−1 + paclobutrazol in the second year. The highest grain protein (14.69%) was seen in nitrogen 150 kg ha−1 + gibberellic acid in the second year and nitrogen 150 kg ha−1 + gibberellic acid in the first year. Growth regulators usage and increasing the nitrogen content (150 kg ha−1), improved the yield and grain quality of wheat. Therefore, the interaction of nitrogen 150 kg ha−1 + gibberellic acid and nitrogen 150 kg ha−1 +paclobutrazol, were the best treatments of this study, due to the creation of suitable environmental conditions for wheat, and these treatments can be suggested to the farmers.

Pruning and Chemical Manipulation Influence Leaf Physiological Parameters and Pod Yield Parameters of Perennial Moringa (Moringa oleifera Lam.) cv. Kappalpatti Local During Off-Season

Understanding and controlling the physiological processes that regulate flowering is crucial for producing crops in off-season. To explore this, an experiment was conducted involving various pruning intensities and chemical sprays to induce off-season flowering and fruiting in moringa trees. The experiment followed a Factorial Randomized Block Design, with Factor I representing pruning at four levels: P-1 (No pruning), P-2 (Pinching off the previous year's growth of fruiting branches), P-3 (Light pruning, removing 33% of previous year's growth), and P-4 (Severe pruning, removing 66% of previous year's growth). Factor II involved chemical sprays at seven levels: C-1 (Control - water spray), C-2 to C-7 (Different chemical treatments). A total of 28 treatment combinations were tested with two replications each. Pruning was performed in the second week of July, and chemicals were sprayed twice, with the first application 30 days after pruning and the second 15 days thereafter. Various physiological parameters such as nitrate reductase activity, total carbohydrate content, nitrogen content, carbohydrate: nitrogen ratio, soluble protein, IAA oxidase activity, and gibberellic acid content in leaves were measured using standard procedures. Pod yield-related characteristics such as number of panicles per tree, number of flowers per panicle, number of pods per panicle, and total pod yield per tree were also recorded. Statistical analysis was conducted following Panse and Sukhatme's procedures (1985), revealing significant effects on various physiological parameters by pruning, chemicals, or their combinations. These alterations in physiological parameters induced flowering during the off-season in perennial moringa cv. Kappalpatti local. Notably, the interaction between pinching and foliar application of nitrobenzene at 0.5% (P2 × C7) resulted in 61.15 panicles per tree, while severe pruning combined with foliar application of paclobutrazol at 50 ppm (P4 × C2) led to 125.45 flowers per panicle. Additionally, the interaction between light pruning and foliar application of paclobutrazol at 50 ppm (P3 × C2) showed significantly higher mean numbers of pods per panicle (2.95) and pod yield per tree (14.14 kg).

Effects of Paclobutrazol on Reproductive and Vegetative Traits of Phalaenopsis Join Grace 'TH288-4'.

Phalaenopsis is the most popular potted plant worldwide. However, its typically long stalks often lead to increased shipping costs and risks. This study investigates the effectiveness of varying the concentration, timing, and frequency of paclobutrazol (PP333) applications on shortening the stalk of Phalaenopsis Join Grace 'TH288-4'. Concurrently, it also examines the potential for producing visually appealing and single-flower potted phalaenopsis products by means of truncation. Mature phalaenopsis plants were moved to a cool room in the seventh week to induce flowering. Four experimental groups were established based on different PP333 application schedules: the control (CK) group, with reverse osmosis water application in the second week; the T2 group, with a single application in the second week; the T2T3 group, with applications in both the second and third weeks; and the T7T8 group, with applications in the seventh and eighth weeks. The PP333 concentrations used were 250, 500, 750, and 1000 mg·L-1, applied as foliar sprays. The results showed that the shortest stalks, measured from the base to the first flower, were observed in the T2 group treated with PP333 at 750 mg·L-1 and in the T2T3 group with PP333 at 500, 750, and 1000 mg·L-1. These treatments resulted in stalk lengths of 19.18-22.17 cm, which are 67.2-71.6% shorter than the controls. PP333 application had minimal effect on the stalk diameter, pedicel length, flower width, length, and length/width ratio. However, root diameter was thicker in plants treated with PP333 compared with the control plants. For producing single-flower phalaenopsis, a foliar spray of 750 mg·L-1 PP333 is recommended approximately a month before moving the plants to cooler conditions, followed by truncation, retaining only the first flower. As a result, this study establishes a PP333 treatment protocol for phalaenopsis, offering a strategy to effectively shorten the stalks.

The Application of Paclobutrazol to GA3-Treated Seed Tuber Potato Fields Does Not Shorten the Growth Cycle or Mitigate Tuber Elongation.

Potato seed tubers are a valuable product in potato agriculture. Over the years, studies have been conducted to increase the fraction of mid-size tubers, which are used as a planting material, within the general pool of tuber sizes. Gibberellic acid has been a central component of such studies and has successfully increased the seed-size pool. However, in many cases, misshapen tubers were formed, and the practice has not become widespread. The use of the gibberellic acid inhibitor paclobutrazol has been examined for its ability to increase seed tuber number and tuber growth and to overcome the heat inhibition of tuberization in warm climates. Paclobutrazol has been shown to increase tuber yield and growth rate. In this study, we aimed to test whether the combination of gibberellic acid and paclobutrazol can increase the seed tuber pool, reduce the number of misshapen tubers, and shorten the growth cycle, thus avoiding end-of-season elevated heat conditions and reducing agricultural inputs. Our findings suggest that gibberellic acid on its own can lead to an increase in the number of seed tubers at earlier stages of growth; however, the sequential addition of paclobutrazol was not able to drive even earlier growth or lower the number of misshapen tubers.

Paclobutrazol Enhanced Stem Lodging Resistance of Direct-Seeded Rice by Affecting Basal Internode Development.

The objectives of this study were to explore the mechanism of stem mechanical strength in direct-seeded rice (DSR) as affected by paclobutrazol, especially its related endogenous hormone and cell wall component changes in culm tissue and response to the application of paclobutrazol. Field experiments were conducted in Changchun County, Jilin Province, China, by using two japonica rice varieties, Jiyujing and Jijing305, with soaking seeds in paclobutrazol at concentrations of (0 mg L-1, S0; 50 mg L-1; S1; 100 mg L-1; S2; 150 mg L-1, S3; 200 mg L-1, S4) in 2021 and 2022. The results suggest that the application of paclobutrazol increased the grain yield and reduced the lodging rate of DSR. Compared with the S0 treatments, soaking the seeds in paclobutrazol treatments rapidly shortened the length of the basal internode by decreasing the endogenous indole acetic acid (IAA) and gibberellin A3 (GA3) contents in culm tissue. The larger breaking strength (M) was attributed to a higher section modulus (SM) and bending stress (BS). The higher mechanical tissue thickness in culm tissue under paclobutrazol treatments, which was raised by higher endogenous zeatin and zeatin riboside (Z+ZR) content in culm tissue, increased the culm diameter, culm wall thickness, and section modulus (SM) of the internode. Compared with the S0 treatments, soaking the seeds in paclobutrazol treatments increased the cellulose content, lignin content, activities of lignin-related enzymes, and expression of key genes in lignin biosynthesis, as well as resulted in a higher bending stress (BS) to enhance the culm breaking strength (M).

Gibberellin Inhibitors Molecules as a Safeguard against Secondary Growth in Garlic Plants

Secondary growth in garlic depreciates its visual aspect and thereby renders the crop unviable for trade. Therefore, farmers commonly reduce fertilization and impose drought and oxidative stress caused by high-dose pesticides to reduce secondary growth in garlic plants. However, these procedures can be considered adverse, unhealthy, and environmentally inappropriate. To remedy this scenario, we investigated whether spraying growth inhibitors would prevent secondary growth in garlic plants. First, we evaluated the effects of abscisic acid, trinexapac-ethyl, chlormequat chloride, and paclobutrazol treatments on garlic plants grown in polyethylene tanks (250 m3). We then analyzed the effects of deficit irrigation combined with the application of trinexapac-ethyl (sprayed two or three times) and the application of trinexapac-ethyl, chlormequat chloride, or paclobutrazol alone (each sprayed two or three times) on garlic plants grown in the field, comparing them with the effects of deficit irrigation (control treatment) alone. The in-field experiment was replicated with the following treatments: control (deficit irrigation) and trinexapac-ethyl (sprayed two or three times) treatments. We analyzed the physiological, biometric, and production parameters affecting secondary growth in garlic plants. We observed that trinexapac-ethyl could efficiently regulate secondary growth without causing physiological disturbances in garlic plants. Our results provide valuable information that will contribute to the development of a sustainable technique to replace the current practices used by farmers to prevent secondary growth in garlic plants.

EFFECT OF PACLOBUTRAZOL AND ABSCISIC ACID APPLICATION ON GROWTH AND PRODUCTIVITY OF CANOLA (Brassica napus L.)

Canola (Brassica napus L.) is an important non-conventional oilseed crop that can be grown in diverse soil and climatic conditions. However, seed shattering after maturity is a major problem in canola production as it can cause up to 50% yield loss if harvesting is delayed due to adverse conditions. Different agronomic and physiological interventions can be opted to enhance yield stability and shattering resistance in canola. The present field study aimed at exploring the potential effects of paclobutrazol and abscisic acid on the growth and yield contributing attributes of canola. The treatments of the experiment included a control (no-spray), water spray, paclobutrazol (50 mg L-1), abscisic acid (0.5 mM), and a combination of paclobutrazol+ abscisic acid (50 mg L-1+0.5 mM). The current experiment examined two canola cultivars, Hybrid (45S42) and Inbred Sandal Canola. The experiment was laid out under Randomized Complete Block Design (RCBD) with a factorial arrangement having three replications. The results showed that exogenous application of paclobutrazol and abscisic acid alone or in combination significantly affected both canola cultivars. The plant height decreased significantly however, leaf area index, grain weight, number of seeds per silique, and number of branches per plant were increased compared with the control. Moreover, the combination of paclobutrazol and abscisic acid recorded a higher increase in leaf area index, dry matter accumulation, plant yield, and number of seeds per pod than their individual application. Between cultivars, the Hybrid cultivar (45S42) recorded better yield as compared to the Inbred Sandal Canola. These results thereby suggest that Hybrid (45S42) cultivar with combined application of paclobutrazol and abscisic acid can be a suitable option for gaining high yield and productivity

Morphological and physiological investigations reveal the regulatory effect of exogenous paclobutrazol on flowering promotion by winter warming in Chaenomeles speciosa ‘Changshouguan’

The application of exogenous paclobutrazol (PP333) can improve the ability of winter warming to promote flowering in Chaenomeles speciosa, but the underlying mechanism is unclear. In this study, the cultivar ‘Changshouguan’ was sprayed with different concentrations of PP333 during flower bud differentiation, and the changes in the anatomical structures and physiological characteristics of the flower buds during the differentiation process, as well as the growth state of the flower buds and the effect on flowering promotion after winter warming treatment, were comprehensively investigated. The results showed that different concentrations of PP333 could advance the flowering time of ‘Changshouguan’ by 15–24 d under the warming treatment and increase the flowering duration to 17 d compared with those under the warming treatment alone (CK), and 1000 mg/L was the best treatment. Compared with the CK treatment, the PP333 treatment decreased the contents of indole acetic acid (IAA) and gibberellic acid (GAs) and increased the contents of zeatin ribosides (ZRs) and abscisic acid (ABA), thus changing the balance of hormones during flower bud differentiation. The inflection point (low point) of the curve shapes of the ZRs/GAs and ZRs/IAA ratios appeared significantly earlier, which showed a pattern consistent with soluble sugar and protein content and antioxidant activity. Interestingly, the above changes also corresponded to earlier flowering times during the warming process. Taken together, these results indicate that spraying an appropriate concentration of PP333 in the early stage of ‘Changshouguan’ flower bud differentiation promotes the early differentiation of flower buds and early flowering under winter warming treatment by altering their endogenous hormone content and homeostasis and changing their physiological state. The key to maintaining a relatively long flowering period in plants in the PP333 treatment group after flowering promotion was the increased accumulation of sugars and proteins.

Integrated Methylome and Transcriptome Analysis between Wizened and Normal Flower Buds in Pyrus pyrifolia Cultivar 'Sucui 1'.

Here, cytosine methylation in the whole genome of pear flower buds was mapped at a single-base resolution. There was 19.4% methylation across all sequenced C sites in the Pyrus pyrifolia cultivar 'Sucui 1' flower bud genome. Meantime, the CG, CHG, and CHH sequence contexts (where H = A, T or C) exhibited 47.4%, 33.3%, and 11.9% methylation, respectively. Methylation in different gene regions was revealed through combining methylome and transcriptome analysis, which presented various transcription trends. Genes with methylated promoters exhibited lower expression levels than genes with non-methylated promoters, while body-methylated genes displayed an obvious negative correlation with their transcription levels. The methylation profiles of auxin- and cytokinin-related genes were estimated. And some of them proved to be hypomethylated, with increased transcription levels, in wizened buds. More specifically, the expression of the genes PRXP73, CYP749A22, and CYP82A3 was upregulated as a result of methylation changes in their promoters. Finally, auxin and cytokinin concentrations were higher in wizened flower buds than in normal buds. The exogenous application of paclobutrazol (PP333) in the field influenced the DNA methylation status of some genes and changed their expression level, reducing the proportion of wizened flower buds in a concentration-dependent manner. Overall, our results demonstrated the relationship between DNA methylation and gene expression in wizened flower buds of P. pyrifolia cultivar 'Sucui 1', which was associated with changes in auxin and cytokinin concentrations.

Growth Responses of Okra (Abelmoschus esculentus L. Moench) to Selected Plant Growth Regulators

This study was conducted to evaluate the effects of two types of plant growth regulators (PGRs) which are gibberellins (GA3) and Paclobutrazol (PBZ) on the growth and photosynthetic pigment (chlorophyll) of Okra (Abelmoschus esculentus L. Moench) plants. Exogenous applications of GA3 and PBZ with different concentrations (i.e. 20, 40, 80 and 100 mg/L) were sprayed on two-week-old Okra plants under the nursery stage. The control plants were only treated with distilled water. The stem diameter (mm) of treated and control plants was measured weekly. At the end of the experimental period, data on growth characteristics such as plant height (cm), leaf area (cm2) and number of leaves were recorded. The estimation of chlorophyll was measured using the SPAD-502 Chlorophyll Meter. Results showed that the plant morphological characteristics of Okra plants were significantly affected by the application of GA3 and PBZ (P<0.0001). In addition, stem growth (expressed as stem cross-sectional area- mm2) of Okra plants was significantly increased with increasing GA3 concentrations. In contrast, applying PBZ reduced Okra plants' stem growth. This study highlighted the major effects of GA3 and PBZ on the growth of Okra plants when planted under tropical climate conditions.

Flowering and production of Palmer mango trees under organic compound and paclobutrazol application

Flowering and production of Palmer mango trees under organic compound and paclobutrazol application