Concentrations Of Paclobutrazol Research Articles

Seed tuber production of potato from stem cuttings, planting densities, and paclobutrazol concentrations

Rapid multiplication of potato seed using cuttings is a pivotal strategy for ensuring seed availability. This study aimed to elucidate the interactive effects of node number, paclobutrazol concentration, and planting density on seed potato and cutting productions. The study consisted of two experiments. The first experiment evaluated two genotypes (Granola and PKHT-6) with one or two nodes per cutting. The second experiment investigated planting density (one, three, or five plants per polybag) and paclobutrazol concentration (0, 15, 30, and 45 mg L-1). Notably, node number did not significantly influence cutting success, despite genotype-specific and interactive effects on vegetative parameters like plant height, stem diameter, leaf number, and root length. Planting density had no statistically significant impact on all vegetative parameters but demonstrably affected all production parameters. Conversely, paclobutrazol concentration significantly affected all vegetative parameters and influenced all production parameters except tuber weight per plant. From the results of this research, the use of single cutting is more recommended because it will obtain more plant material compared to two-node cuttings. Thus, in a more global context of potato development, this has the potential to increase the production of potato seeds from cuttings twice as much as the current seed production. The use of three plants/polybags is more recommended since it will produce more tuber but not different with five plants, and the use of paclobutrazol 15 mg L-1 is also recommended to increase the number of tubers. In this way, the production costs of G0 potato seeds can be reduced so that the availability of G0 potato seeds will be more guaranteed and affordable. Keywords: Granola; PKHT-6; rapid multiplication; tuber production

Effect of Paclobutrazol and GA4+7 on Post-Harvest Storage of Dragon Fruit [Hylocereus costaricensis (Web.) Britton and Rose

Dragon fruit undergoes rapid senescence during storage. This study identified the synergistic effect of Paclobutrazol and GA4+7 with different concentrations on the postharvest quality and shelf life of dragon fruits stored at ambient conditions. This study was conducted in completely randomized design. Dragon fruits were treated with different concentration of Paclobutrazol and GA4+7 and stored at ambient temperature for 13 days. Changes in fruit’s physiological loss of weight, firmness, total soluble solid, titrable acidity, and ascorbic acid were periodically recorded. The results indicated that the Paclobutrazol treated with 200mg significantly reduced the decrease of physiological loss of weight, firmness, total soluble solids, titrable acidity and ascorbic acid content. The results showed that Paclobutrazol treated with 200mg is the most effective treatment than GA4+7 for improving the postharvest quality and prolong the shelf life of dragon fruits when stored at ambient condition.

Response of growth, yield, and seeds quality of G0 potato on different potassium fertilizer doses and retardant concentrations in Jatinangor medium land

This study aims to determine the best interaction of potassium (K) fertilizer dose and retardant concentration on the growth, yield, and seed quality of G0 potato grown in the medium land of Jantinangor. The experiment was conducted at Screen House Station Ciparanje, Jatinangor, Faculty of Agriculture Universitas Padjadjaran from November 2022 until January 2023 at an elevation of ± 685 meters above sea level. The experimental design used was the Factorial Randomized Block Design (RBD). The first factor was the K fertilizer dose including 50%, 100%, and 150%. The second was the retardant concentration including without retardant, 100 ppm paclobutrazol, 100 ppm prohexadione-Ca, and 150 ppm prohexadione-Ca. The experimental results showed that there was an interaction effect between the K dose and retardant concentration. The interaction effect of 150% K and 100 ppm prohexadione-Ca showed the highest percentage of L class seed tuber and the lowest tuber weight loss. Independently, 150% K improved growth rate, number of tubers (6.67 knol/plant), and weight of tubers (73.33 g/plant). Independently, 100 ppm paclobutrazol concentration increased the chlorophyll content index. 150 ppm prohexadione-Ca concentration suppressed leaf area and plant height but increased stomatal conductance, fast emergence shoot time, and shoot length. 100 ppm prohexadione-Ca concentration produced the highest number of tubers and the weight of tubers, i.e., 6.78 knol/plant and 74.33 g/plant, respectively.

Paclobutrazol Residues in Recirculated Water in Commercial Greenhouses

Reusing irrigation water has technical, environmental, and financial benefits. However, risks are also associated with the accumulation of agrochemicals, in addition to ions, plant and food safety pathogens, and biofilm organisms. In this project, we measured the concentration of paclobutrazol (a persistent and widely used plant growth regulator) in recirculated water in greenhouses producing ornamental plants in containers. Solutions were collected from catchment tanks at nine commercial greenhouses across seven states in the United States in Spring and Fall 2014. Paclobutrazol was detected in all samples, with differences observed by season, greenhouse operation, paclobutrazol application method, and irrigation method. Across operations, the residual concentration of paclobutrazol was higher in spring for most greenhouses (ranging from 0 to 1100 µg·L−1) compared with the fall (ranging from 0 to 8 µg·L−1). The spray-drench application method resulted in the highest residual concentrations (up to 35 µg·L−1), followed by substrate drench (up to 26 µg·L−1) and foliage spray (concentrations under 3 µg·L−1). Residual concentrations were higher with overhead irrigation (up to 35 µg·L−1) compared with subirrigation systems (up to 15 µg·L−1). Our results indicate that paclobutrazol is likely to be a growth retardant risk in greenhouse operations recirculating water. A clear understanding of the risks associated with recirculated water intends to support the development and implementation of risk management strategies to ensure and promote safe use of recirculated water in greenhouses. Overall, the most effective preventative strategy is to ensure the use of the minimum amount of the a.i. necessary per unit of space and time.

Application of soil amendments and paclobutrazol to shorten internode and increase rice yields

This study aims to determine the role of soil amendments, Paclobutrazol (PBZ), and varieties as well as their interactions on the growth and yield of rice. This study used a randomized block design (RBD) factorial split-split plot 3 x 2 x 2 with 3 replicates. The first factor was soil amendments as the main plot which consisted of 3 levels: A1= biochar, A2= compost, A3= mixture of biochar, compost, Mycorrhiza, and Trichoderma. The second factor was the concentration of PBZ in the split plot, which consisted of 2 levels: PBZ1 = 500 ppm, and PBZ2 = 700 ppm. The third factor is the variety as a split-split plot consisting of 2 levels: V1 = Sigupai Abdya, V2 = Tangse. The results showed that soil amendments had a significant effect on grain weight, and yield potential. The best yields are found in 50 g pot−1 of compost. PBZ had a very significant effect on grain weight and yield potential. PBZ at 700 ppm, can shorten rice internodes. Varieties have a very significant effect on grain weight and yield potential. The best growth and yields were found in the treatment of 50 g pot−1 compost with PBZ at a concentration of 700 ppm using the Tangse variety.

Response of off-season strawberries (Fragaria sp.) production under the effects of paclobutrazol and drought stress

Strawberry (Fragaria sp.) is a fruit crop harvested seasonally with the peak season from August to November while the off-season harvest is January to June with limited harvest. The purpose of this study was to find the concentration of paclobutrazol and the level of drought stress for off-season strawberry production. This research conducted on April to July 2023. The experiment used a factorial Randomized Block Design consisting of 2 factors and 3 replications with 16 treatment combinations. The first factor was paclobutrazol consisting of four levels, namely P0 = control, P1 = 10,000 ppm, P2 = 20,000 ppm and P3 = 30,000 ppm and the second factor was the level of drought stress consisting of four levels i.e. C0 = 100% field capacity, C1 = 80% field capacity, C2 = 60% field capacity and C3 = 40% field capacity. The results showed that paclobutrazol accelerated flowering time, increased fruit set, leaf relative water content, root length, chlorophyll content, but decreased the number of fruits formed, harvested fruits, fruit diameter, harvested fruit weight, weight per fruit, root oven dry weight, percentage of fallen fruits and total soluble solids. Drought stress level increased leaf relative water content, root length, root oven dry weight, percentage of fallen fruit, percentage of fruit set, but decreased number of flowers formed, fruits harvested, weight of fruits harvested, weight per fruit, fruit diameter, total soluble solids, chlorophyll content and delayed flowering time.

Effects of paclobutrazol seed priming on seedling quality, photosynthesis, and physiological characteristics of fragrant rice

BackgroundPaclobutrazol is widely used in the agricultural field. This study investigated the effects of seed priming with different concentrations of paclobutrazol on seedling quality, 2-acetyl-1-pyrroline (2-AP, a key aroma component of fragrant rice) biosynthesis, and related physiological and biochemical indicators in fragrant rice seedlings.ResultsThe experiment is being conducted at the College of Agriculture, South China Agricultural University. In the experiment, three concentrations of paclobutrazol (Pac 1: 20 mg·L−1; Pac 2: 40 mg·L−1; Pac 3: 80 mg·L−1) were used to initiate the treatment of fragrant rice seeds, while water treatment was used as a control (CK). The results showed that compared with CK, paclobutrazol treatment reduced plant height, increased stem diameter, and increased fresh and dry weight of aromatic rice seedlings. Moreover, paclobutrazol treatment also increased the seedlings’ photosynthetic pigment content and net photosynthetic rate.ConclusionsThis study demonstrates that paclobutrazol primarily increases the content of proline by reducing the content of glutamate and down-regulating the expression of P5CS2, thereby promoting the conversion of proline to the aromatic substance 2-AP. Under the appropriate concentration of paclobutrazol (40 mg·L−1~80 mg·L−1), the seedling quality, stress resistance, and aroma of fragrant rice can be improved.

Optimization of Potato Cuttings of Granola Kembang Cultivars with the Application of Auxin and Paclobutrazol for Tuber Production

Optimization of Potato Cuttings of Granola Kembang Cultivars with the Application of Auxin and Paclobutrazol for Tuber Production

Cultivo de abobrinha sob estresse salino e aplicação exógena de paclobutrazol

ABSTRACT Salinity is considered an obstacle to the production system that limits the growth and yield of crops around the world. Therefore, it is essential to develop strategies to minimize the effects of salinity and increase yield, especially in the semi-arid region of the Northeast, which has limited water resources of good quality for irrigation. The objective was to evaluate the effects of applying paclobutrazol on zucchini crop under salt stress. The experiment was conducted in a greenhouse, in a randomized block experimental design, in a 2 × 5 factorial scheme, with two salinity levels of irrigation water (0.6 and 4.0 dS m-1) and five concentrations of paclobutrazol - PBZ (0; 2; 4; 6 and 8 g L-1), and with four repetitions. Application of 8 mg L-1 PBZ increases stem diameter in zucchini under irrigation of 4.0 dS m-1. Chlorophyll b and total chlorophyll contents increase with PBZ concentration of 4 mg L-1 and irrigation of 0.6 dS m-1. PBZ concentration of 4 mg L-1 increases the relative water content while reducing electrolyte leakage in zucchini under salinities of 4.0 and 0.6 dS m-1 respectively. Root, stem and leaf dry mass of zucchini increases when plants are irrigated with water of 0.6 dS m-1 and subjected to PBZ concentration of 8 mg L-1. PBZ concentrations do not attenuate the effects of salinity on leaf area, crown volume and diameter, vegetative vigor index, chlorophyll a and carotenoids.

Interactive effects of NPK fertilizer and paclobutrazol concentration on growth and yield of hanjeli (Coix lacryma-jobi L.)

The balance between growth and crop yield can be manipulated by exploiting nutrient and retardant interactions. This study is aiming to assess the effects of various combinations of NPK 16-16-16 fertilizer in different doses, along with the application of multiple concentrations of paclobutrazol on the growth and yield of hanjeli. This experiment was carried out in the experimental field of Ciparanje, Faculty of Agriculture Universitas Padjadjaran, Jatinangor, Sumedang from February 2021 to August 2021. This research was conducted in a split-plot design with three replications. The main plot consisted of 200 kg/ha (n1), 250 kg/ha (n2), and 300 kg/ha (n3). The subplot consisted of 2000 ppm (p1), 3000 (p2), and 4000 ppm (p3). The results show that there were interaction effects between different doses of NPK fertilizer and paclobutrazol concentrations on plant height and 100-grain weight. The best combination came from the application of 200 kg/ha NPK fertilizer with 3000 ppm of paclobutrazol, which gave higher results in plant height and 200 kg/ha NPK fertilizer with 2000 ppm of paclobutrazol on 100-grain weight.

Productivity and Econometric Analysis of Leguminous Monkey-nut (Arachis hypogaea L.) as Influenced by Growth Retardant

Background: Groundnut (Arachis hypogaea L.) holds significant importance as a staple food legume and a key economic crop, serving as a valuable source of edible oil and protein in India. However, its full yield potential is often hampered by excessive vegetative growth, which leads to suboptimal yields. With this background, a field experiment was conducted at the Perunthalaivar Kamaraj Krishi Vigyan Kendra in Puducherry during 2020 and 2021. The objective was to investigate the influence of different concentrations and timing of paclobutrazol (PBZ) application on the growth and yield of groundnut. Methods: The experiment was laid out in a split-plot design with three replications, six main plot treatments (Including PBZ concentrations of 25, 50, 100, 150, 200 ppm and a control) and three sub-plot treatments (Involving single sprays at 30 days after emergence (DAE), single sprays at 50 DAE and double sprays at 30 and 50 DAE). Result: The results revealed that the application of paclobutrazol at different concentrations had a positive effect on reducing plant height during the later stages of growth, particularly when a double spray was applied at 30 and 50 DAE. Notably, the application of paclobutrazol at a concentration of 200 ppm in groundnut cultivation proved to be economically viable, resulting 29% increase in pod yield compared to the control group. Specifically, PBZ at 200 ppm, with a double spray, significantly boosted the total pod yield to 2724 kg ha-1. Furthermore, the correlation and regression analyses indicated a positive relationship between growth and yield.

Pengaruh Teknik Hardening dan Konsentrasi Paclobutrazol terhadap Pertumbuhan Planlet Krisan (Chrysanthemum sp.) pada Tahap Aklimatisasi

The increasing interest and demand for chrysanthemum plants affect their economic value, which causes the quality of chrysanthemum plants to be demanded from all sides. One of the efforts to meet the needs of chrysanthemum plants in a short time is tissue culture. However, the acclimatization stage becomes a critical stage that threatens the presentation of chrysanthemum plantlets. This study aimed to determine the interaction between hardening techniques and paclobutrazol concentration on the growth of chrysanthemum plantlets at the acclimatization stage. This research was conducted in the Green House of the Tissue Culture Laboratory of Jember Polytechnic from November 2022 to January 2023. This study used a factorial complete randomized design (CRD) repeated 4 times. The first factor is the hardening technique consisting of 2 levels, H0 (no hardening), and H1 (hardening). The second factor is paclobutrazol concentration which consists of 3 levels, P1 (10 ppm), P2 (15 ppm), and P3 (20 ppm). Observational data were statistically analyzed using ANOVA, if the results showed significantly different effects then continued with the BNT test at the 5% level. The results showed that the hardening treatment had a significantly different effect on leaf color with a score of 3.5. Treatment with a paclobutrazol concentration of 20 ppm had a significantly different effect on increasing plant height by 2.71 cm and increasing the number of leaves by 1.38. This suggests that paclobutrazol and hardening treatment are needed at the acclimatization stage of chrysanthemums.

The effect of varieties of true shallot seed and paclobutrazol concentrations on growth and production of shallot plant

The increasing demand for shallots is inversely proportional to the quality of the current production. Efforts to improve and increase quality of production are selection of good varieties and add plant regulatory substances has also become the focus of many researchers in their effect on plant growth. Therefore, research was carried out on the effect of the varieties and also plant regulatory substances namely paclobutrazol on the growth and production of shallot plants. This research was carried out at the Teaching Farm, Faculty of Agriculture, Hasanuddin University from August to November 2021. This research was carried out as a factorial experiment in a split plot design, as the main plot, namely the botanical seed varieties of shallot (v) consists of 3 varieties, namely the Lokananta varieties (v1), Maserati varieties (v2), and Sanren varieties (v3), as a sub-plot, namely the concentration of paclobutrazol consists of 4 levels, namely 0 ppm (k0), 100 ppm (k1), 200 ppm (k2) and 300 ppm (k3). The research results showed that the interaction of the Sanren varieties with paclobutrazol concentration of 100 ppm gave the best results on the weight of fresh stover per plant (26.04 g), weight of dry stover per plant (19.23 g) and production per hectare (9.20 ton/ha). The Sanren varieties gave the best results on chlorophyll a (387.23 μmol.m−2), chlorophyll b (187.12 μmol.m−2), total chlorophyll (564.14 μmol.m−2) and number of tubers (1.81). Paclobutrazol concentration of 100 ppm gave the best results on plant height (43.07 cm) and number of leaves (6.24 strands), while paclobutrazol concentration of 200 ppm gave the best results on tuber diameter (23.13 mm) and paclobutrazol concentration of 300 ppm gave the best results on the number of tubers (1.54).

Impact of paclobutrazol on storage root number and yield of sweet potato (Ipomoea batatas L.)

Increasing storage root number is an important way to improve the yield of sweet potato. Here, two-year field experiments were conducted to study the effect of 0 (CK), 10, 20 and 30 mg kg−1 paclobutrazol (PBZ) on the phytohormones and lignin biosynthesis, and root growth and yield of sweet potato. The current study found that PBZ10 decreased the concentration of phytohormones gibberellin 3 (GA3), indole acetic acid (IAA) and abscisic acid (ABA) in the subterranean stem, whereas increased the concentration of zeatin riboside (ZR) and methyl jasmonate (MeJA), resulting in lower root length, volume and tip number at 3 and 5 days after planting (DAP). At 5 DAP, PBZ10 decreased GA3, MeJA and ABA concentration in adventitious root, and increased IAA and ZR concentrations, resulting in increased root length, volume, tip number and surface area at 10 DAP. By 5–30 DAP, PBZ10 decreased the concentration of GA3 and ABA in potential storage roots and increased the concentration of IAA, ZR and MeJA, thus increasing root number. At 10–20 DAP, PBZ10 decreased the lignin concentration in the potential storage root along with the expression of IbEXP1 and the enzymatic activities of phenylalanine ammonialyase, 4-coumaric acid CoA ligase and peroxidase, which are involved in the regulation of lignin biosynthesis, resulting in increased potential storage root diameter; interestingly, the opposite pattern was observed by 25–30 DAP. Then, PBZ10 increased the SR number at 40 DAP, and the yield of sweet potato at harvest time, and no PBZ was detected in SRs of PBZ10. But excessive concentration of PBZ is unfavorable to root development and led to a decrease of yield. These results indicated that a moderate PBZ (10 mg kg−1) application could reasonably regulate phytohormones and lignin biosynthesis, then increase storage root number and yield of sweet potato.

Paclobutrazol in the in vitro conservation of cassava genotypes

In vitro germplasm conservation allows to extend the interval between subcultures without compromising the viability and genetic integrity of the plant, ensuring a backup of genotypes with high phytosanitary quality. Thus, this study aimed to verify the effect of four concentrations of Paclobutrazol® in inducing minimum growth in five Manihot esculenta accessions from the in vitro Active Germplasm Bank of Embrapa Cassava and Fruits. An experiment was installed using the Murashige and Skoog medium without addition and added with four concentrations of Paclobutrazol® (0.10, 0.20, 0.30, and 0.40 mg L-1), in five in vitro accessions of M. esculenta: BRS Jari (BGM 2041), Cigana (BGM 0264), BRS Poti Branca (BGM 2017), TME 14, and BRS Novo Horizonte. The statistical design was completely randomized in a 5 x 5 factorial scheme, with 15 repetitions. After 120 days of cultivation, the following variables were evaluated: plant height (cm), number of green leaves, number of senescent leaves, number of mini-cuttings, number of shoots, and fresh and dry mass of shoots and roots (mg). Paclobutrazol® caused a reduction in plant height and gain in root mass for all accessions, in addition to preserving the number of green leaves and decreasing leaf senescence for most genotypes. There was a strong dependence of the genotype in relation to the concentration of Paclobutrazol®. The concentration of 0.20 mg L-1 showed potential in the in vitro conservation of M. esculenta genotypes.

Effect of sucrose and paclobutrazol concentrations and photoperiod in Dioscorea spp. Microtuberization

Effect of sucrose and paclobutrazol concentrations and photoperiod in Dioscorea spp. Microtuberization

Respons Tanaman Angelonia (Angelonia angustifolia) terhadap Pemberian Paclobutrazol

Ornamental plants have now developed as souvenirs given at a wedding. Requirements for souvenirs, the plants should be tiny, lush, and have much of flowers. So its growth needs to be modified using a growth regulator paclobutrazol. This study aimed to determine the response of angelonia plants to the application of paclobutrazol at several levels of concentration and determine the concentration of paclobutrazol which has the best appearance of angelonia plants. This research method used a randomized block design (RBD) with treatment of 6 levels of paclobutrazol concentration, namely 0 ppm, 30 ppm, 60 ppm, 90 ppm, 120 ppm and 150 ppm with 3 replications. The F test and further tests were carried out an Orthogonal Polynomials. All tests were carried out at the 5% level. The results showed that the application of paclobutrazol at a concentration level of 30-150 ppm, was effective in suppressing the growth rate of angelonia plants in the vegetative phase. This value was proved by the results of the questionnaire that, the highest visual value was obtained at a concentration of 150 ppm. But with the increasing concentration of paclobutrazol, the freshness of flowers became shorter. Keywords: Angelonia, Concentration, Paclobutrazol

Influence of Shading and Paclobutrazol Concentrations on Growth and Quality Characters of Three Different Turf Grasses Genera

This study was carried out in Pirmam,, Erbil Governorate - Iraq for two years, from 15 March 2020 to 15 March 2021 in the spring season and from 15 September2020 to 15 September 2021 in the autumn season, to study the responses of three turf grass genera, includingermuda grass (Cynodon dactylon L. var. cd4), Tall fescue grass (Festuca arrundaceae L. var. Barleroy) and Creeping bent grass (Agrostis palustris) cultivated by seeds to two shading levels of 0 and 75% and sprayed with three paclobutrazol concentrations at 0, 750 and 1500 mg. l-1. The experiment was performed by using Randomized Complete Block Design (RCBD) in a split-plot design with three factors and three replications. The results showed that the shading level (0%) led to a significant increase in most studied characters like mowing number, cumulative dry weight of turf grass clipping yield, dry root weight, total chlorophyll and carbohydrate percentage and was superior to those grown under 75% shading. Both levels of shading had no significant effects on color degree and coverage percentage of the used turf grasses. It also showed that foliar spray of paclobutrazol had a significant impact on those traits. The highest values of plant density, mowing number, and cumulative dry weight of clipping yield were recorded when turf grasses were unsprayed with paclobutrazol, while the highest values of color degree, coverage percentage, total chlorophyll content, and carbohydrate percent were obtained when turf grasses were sprayed with 1500 and 750 mg.l-1 of paclobutrazol, respectively. Significant differences were shown among turf grass genera that were grown from seeds in those traits. Agrostise genus was significantly superior to other genera only in plant density, while Festuca genus was significantly superior to other genera in the rest of the other characteristics. As for triple interactions, the highest significant values for most characteristics were found in Festuca genera that were sprayed with 750 and 1500 mg.l-1 concentrations of paclobutrazol and grown in open fields.

Fruit Set dan Daya Simpan Buah Tanaman Cabai Rawit (Capsicum frutescens L.) Akibat Pemberian Paklobutrazol dan Pupuk Organik Cair Buah Pisang

Increasing the productivity of cayenne pepper (Capsicum frutescens L.) can be done through the use of growth regulators, namely paclobutrazol and liquid organic fertilizer. Treatment of paclobutrazol concentrations and doses of liquid organic fertilizer derived from banana fruit waste is expected to increase the fruit set and storability of the resulting cayenne pepper. The purpose of this study was to determine the best concentration of paclobutrazol and POC banana fruit to increase the fruit set of cayenne pepper, and to determine the best concentration of paclobutrazol to produce cayenne pepper with a more resistant shelf life. The research method used was using a Split Plot Design with the main plot being the dosage of liquid organic fertilizer for bananas, which consisted of NPK 40 g/plant (control), 300 ml/plant POC banana, 400 ml/plant and 500 ml/plant POC bananas. While the concentration of paclobutrazol as a sub-plot, which consisted of 0 ppm/without paclobutrazol (control), 100, 150 and 200 ppm. The results showed that there was a significant interaction between the combination treatment concentrations of paclobutrazol and the dosage of liquid organic fertilizer for bananas in the observed parameter of fruit set percentage. A higher percentage of fruit set was obtained from the combination treatment of 150 ppm paclobutrazol concentration with a dose of 300 ml/plant of banana liquid organic fertilizer. The concentration of paclobutrazol had a significant effect on the storability of cayenne pepper. Cayenne pepper that more resistant to storage were obtained from treatment with a concentration of 150 ppm paclobutrazol.

The Effects of Paclobutrazol Seed Soaking on Biomass Production and Yield Formation in Direct-Seeded Rice

Direct-seeded rice has been widely adopted in Asia in recent years. However, its low and unstable yields severely limit the increase in rice production and directly affect food security. The aim of this research was to investigate the effects of different concentrations of paclobutrazol seed soaking on the biomass production and yield formation of direct-seeded rice and to find the optimal concentrations to provide a theoretical basis for the high-yielding cultivation of direct-seeded rice. Two rice varieties, Jiyujing and Jijing305, were used in this experiment, and the seeds were soaked in paclobutrazol at concentrations of 0, 50, 100, 150, and 200 mg L−1. The appropriate concentration of paclobutrazol seed soaking increased the yield of direct-seeded rice; this was attributed to the increase in the spikelet per unit area and the seed setting rate. However, the too-high paclobutrazol concentration was not conducive to a yield increase. Regression analysis showed that the appropriate concentration of paclobutrazol seed soaking was 100–105 mg L−1. The appropriate concentration of paclobutrazol for seed soaking ensured the seedling emergence rate; improved the seedling quality, stem tillers, and productive tillers; increased the efficient leaf area, chlorophyll content, and net photosynthetic rate, resulting in an increase in dry matter accumulation; coordinated the source-sink relationship and dry matter distribution; and promoted the material translocation from the “source” to the “sink”. In conclusion, using the appropriate concentration of paclobutrazol for seed soaking is an effective means of obtaining high yields of direct-seeded rice.