Influence of Media Components on Efficacy of Paclobutrazol in Inhibiting Growth of Broccoli and Petunia

Three experiments were conducted to evaluate media component effects on paclobutrazol activity. In Expts. 1 and 2, a broccoli (Brassica oleracea var. botrytis L.) seedling bioassay was used to compare the activity of paclobutrazol at six concentrations (0-0.32 mg·L-1). Results from Expt. 1 indicated that an average of 4-, 5-, and 10-fold higher concentrations were required in old composted pine bark, fresh pine bark, and composted pine bark samples, respectively, to achieve the same activity observed in sphagnum peatmoss (peat) samples. Activity in coir was similar to that in peat while activity in vermiculite and perlite was greater than that in peat. Activity in a fibrous peat sample was greater than in two less-fibrous peat samples. Results from Expt. 2 indicated that paclobutrazol activity was reduced more in the fine (<2 mm) fraction of fresh and composted bark samples than in medium (2-4 mm) or coarse (>4 mm) fractions. In Expt. 3, petunia {Petunia hybrida Vilm. `Madness Red') was grown in a mixture of either 60% composted pine bark: 0% peat or 0% composted bark: 60% peat. The paclobutrazol concentration required to achieve the same size control was 14 times higher in the former mixture than in the latter. Thus, media components differ greatly in their influence on paclobutrazol activity and the bioassay procedure may serve as a useful tool for predicting media-paclobutrazol interactions. Chemical name used: (±)-(R*,R*)-β-[(4-chlorophenyl)methyl]-α-(l,l-dimethyl)-lH-l,2,4-triazole-l-ethanol (paclobutrazol).

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Influence of Several Container Media Components on Paclobutrazol Efficacy

HortScience ◽

10.21273/hortsci.32.3.436b ◽

1997 ◽

Vol 32 (3) ◽

pp. 436B-436

Author(s):

J. Million ◽

J. Barrett ◽

D. Clark ◽

T. Nell

Keyword(s):

Size Control ◽

Pine Bark ◽

Media Component ◽

Bioassay Procedure

A broccoli seedling bioassay was used to compare the activity of paclobutrazol applied at six concentrations to 20 media component samples mixed 1:1 (v:v) with vermiculite. Results indicated that 4-, 5-, and 10-fold higher media paclobutrazol concentrations were required in old composted pine bark, fresh pine bark, and composted pine bark samples, respectively, to achieve the same activity observed in sphagnum peatmoss. Paclobutrazol bioassay activity in coir was similar to the activity observed in peat, while activity in vermiculite and perlite was greater than in peat. In a second trial, paclobutrazol activity was reduced more in the fine (<2 mm) fraction of fresh and composted bark samples than in medium (2–4 mm) or coarse (>4 mm) fractions. In a third trial, petunias grown in a 60% composted pine bark:0% peat mix required a »14-times higher drench paclobutrazol concentration to achieve the same size control as petunia grown in a 0% composted bark:60% peat mix. It was concluded that media components differed greatly in their influence on paclobutrazol activity and that the bioassay procedure might serve as a useful tool for predicting media–paclobutrazol interactions.

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The Effects of Several Key Factors on the Efficacy of Paclobutrazol Liner Dips for the Control of Stem Elongation in Bedding Plants

HortScience ◽

10.21273/hortsci.41.4.984a ◽

2006 ◽

Vol 41 (4) ◽

pp. 984A-984

Author(s):

Rebecca A. Schnelle ◽

James E. Barrett

Keyword(s):

Growth Regulator ◽

Petunia Hybrida ◽

Stem Elongation ◽

Size Control ◽

Plant Industry ◽

Key Factors ◽

Bedding Plants ◽

Relative Moisture ◽

Bedding Plant ◽

Dry Down

The paclobutrazol liner dip is a plant growth regulator application technique that is becoming widespread in the commercial bedding plant industry. This technique, in which plug trays are dipped in a solution of paclobutrazol before transplant, is an efficient method for applying this growth regulator to a large number of plants. In previous studies, significant variability in size control was documented following liner dip treatments with identical solution concentrations. To elucidate the causes of this variability, three bedding plant species with varying levels of paclobutrazol sensitivity (Petunia ×hybrida, Impatiens wallerana, and Scaevola aemula) were treated with paclobutrazol liner dips under various conditions. Four factors identified in previous studies that may impact the efficacy of paclobutrazol liner dips were evaluated in this study. The age of the cuttings at the time of treatment ranged from 2 to 4 weeks after propagation. The light intensity incident to the plants from 2 h before through 2 h following the time of treatment ranged from about 1000 μmol·m-2·s-1 in a greenhouse to 5 μmol·m-2·s-1 indoors. The relative moisture content of the plug media before the treatment was saturated or at 25%, 50%, or 80% dry down by weight, based on air-dried media. The amount of time the plug media remained in the paclobutrazol solution was 10 s, 30 s, or 2 min. Data were collected on stem elongation 3 weeks after transplanting and again 2 weeks later. The results confirm that all four factors tested interact with the concentration of paclobutrazol in the dip solution to determine the control in stem elongation achieved by the treatment.

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Interfacial studies in Nb3Sn superconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087264 ◽

1991 ◽

Vol 49 ◽

pp. 590-591

Author(s):

Ernest L. Hall ◽

Lee E. Rumaner ◽

Mark G. Benz

Keyword(s):

Grain Size ◽

Grain Boundaries ◽

Flux Pinning ◽

Size Control ◽

High Magnetic Fields ◽

Type Ii ◽

Reaction Interface ◽

Liquid Diffusion ◽

Type Ii Superconductor ◽

Grain Size Control

The intermetallic compound Nb3Sn is a type-II superconductor of interest because it has high values of critical current density Jc in high magnetic fields. One method of forming this compound involves diffusion of Sn into Nb foil containing small amounts of Zr and O. In order to maintain high values of Jc, it is important to keep the grain size in the Nb3Sn as small as possible, since the grain boundaries act as flux-pinning sites. It has been known for many years that Zr and O were essential to grain size control in this process. In previous work, we have shown that (a) the Sn is transported to the Nb3Sn/Nb interface by liquid diffusion along grain boundaries; (b) the Zr and O form small ZrO2 particles in the Nb3Sn grains; and (c) many very small Nb3Sn grains nucleate from a single Nb grain at the reaction interface. In this paper we report the results of detailed studies of the Nb3Sn/Nb3Sn, Nb3Sn/Nb, and Nb3Sn/ZrO2 interfaces.

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Tronchuda cabbage (Brassica oleracea L. var. costata DC) leaf free amino acid profile

Planta Medica ◽

10.1055/s-0028-1084544 ◽

2008 ◽

Vol 74 (09) ◽

Author(s):

BM Silva ◽

AP Oliveira ◽

DM Pereira ◽

C Sousa ◽

RM Seabra ◽

...

Keyword(s):

Amino Acid ◽

Brassica Oleracea ◽

Free Amino Acid ◽

Free Amino ◽

Amino Acid Profile ◽

Tronchuda Cabbage ◽

Brassica Oleracea L

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Size Control of Block Polymer Templated Mesoporous Silicate Materials

MRS Proceedings ◽

10.1557/proc-628-cc6.24 ◽

2000 ◽

Vol 628 ◽

Author(s):

Takeo Yamada ◽

Keisuke Asai ◽

Kenkichi Ishigure ◽

Akira Endo ◽

Hao S. Zhou ◽

...

Keyword(s):

Mesoporous Materials ◽

Molecular Sieve ◽

Mesoporous Material ◽

Triblock Copolymer ◽

Size Control ◽

Block Polymer ◽

New Class ◽

Mesoporous Silicate ◽

Cubic Structure ◽

Silicate Materials

ABSTRACTMesoporous materials have attracted considerable interest because of applications in molecular sieve, catalyst, and adsorbent. It will be useful for new functional device if functional molecules can be incorporated into the pore of mesoporous material. However, it is necessary to synthesize new mesoporous materials with controlled large pore size. Recently, new class of mesoporous materials has been prepared using triblock copolymer as a template. In this paper, we reported that hexagonal and cubic structure silicate mesoporous materials can be synthesized through triblock copolymer templating, and their size was controlled by synthesis condition at condensation.

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A Step Size Control Method Improving Estimation Speed in Double Talk Term

IEICE Transactions on Fundamentals of Electronics Communications and Computer Sciences ◽

10.1587/transfun.e96.a.1543 ◽

2013 ◽

Vol E96.A (7) ◽

pp. 1543-1551 ◽

Cited By ~ 1

Author(s):

Takuto YOSHIOKA ◽

Kana YAMASAKI ◽

Takuya SAWADA ◽

Kensaku FUJII ◽

Mitsuji MUNEYASU ◽

...

Keyword(s):

Control Method ◽

Size Control ◽

Step Size ◽

Step Size Control

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Growth of Dracaena marginata and Spathiphyllum ‘Petite’ in Sphagnum Peat- and Coconut Coir Dust-based Growing Media

Journal of Environmental Horticulture ◽

10.24266/0738-2898-17.1.49 ◽

1999 ◽

Vol 17 (1) ◽

pp. 49-52 ◽

Cited By ~ 4

Author(s):

Robert H. Stamps ◽

Michael R. Evans

Keyword(s):

Growth Parameters ◽

Cocos Nucifera ◽

Greenhouse Production ◽

Growing Media ◽

Sphagnum Peat ◽

Affected Plant ◽

Coir Dust ◽

Media Component ◽

The Media ◽

Cocos Nucifera L

Abstract A comparison was made of Canadian sphagnum peat (SP) and Philippine coconut (Cocos nucifera L.) coir dust (CD) as growing media components for greenhouse production of Dracaena marginata Bak. and Spathiphyllum Schott ‘Petite’. Three soilless foliage plant growing mixes (Cornell, Hybrid, University of Florida #2 [UF-2]) were prepared using either SP or CD and pine bark (PB), vermiculite (V), and/or perlite (P) in the following ratios (% by vol): Cornell = 50 CD or SP:25 V:25 P, Hybrid = 40 CD or SP:30 V:30 PB, UF-2 = 50 CD or SP: 50 PB. Dracaena root growth was not affected by treatments but there were significant mix × media component interactions that affected plant top growth parameters. In general, the growth and quality of D. marginata were reduced by using CD in Cornell, had no effect in Hybrid, and increased in UF-2. S. ‘Petite’ grew equally well in all growing mixes regardless of whether CD or SP was used; however, plants grew more in Cornell and Hybrid than in UF-2. S. ‘Petite’ roots, which were infested with Cylindrocladium spathiphylli, had higher grades when grown in CD than when the media contained SP.

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Evaluation of Pine Bark, Pine Bark With Wood, and Pine Tree Chips as Components of a Container Plant Growing Media

Journal of Environmental Horticulture ◽

10.24266/0738-2898-4.1.22 ◽

1986 ◽

Vol 4 (1) ◽

pp. 22-25 ◽

Cited By ~ 1

Author(s):

A.J. Laiche ◽

V.E. Nash

Keyword(s):

Organic Amendments ◽

Pine Bark ◽

Growth Media ◽

Ligustrum Sinense ◽

Pine Tree ◽

Water Holding ◽

Low Solubility ◽

Low Nitrogen ◽

Very High ◽

Container Plant

Three woody landscape species, Rhododendron indica ‘President Clay’, Ligustrum sinense ‘variegata’, and Ilex crenata ‘compacta’, were grown in media prepared from fresh pine bark, pine bark with wood, and pine tree chips. Although media were variable in physical properties, all exhibited very high hydraulic conductivity and low water holding capacity. The capacity of these media materials to hold fertilizer elements was very low. Nitrogen, potassium, and phosphorus were rapidly removed by leaching while calciuum and magnesium were retained longer because of the low solubility of dolomitic limestone. Pine bark was the best growth media tested for all plant species. Pine bark with wood was less satisfactory than pine bark and growth was poorest in pine tree chips. More research is needed on the use of the organic amendments with greater amounts of wood before being widely used as organic components of growth media.

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EFFECT OF DIFFERENT DOSES OF BORON ON GROWTH AND YIELD OF OFF-SEASON CAULIFLOWER (BRASSICA OLERACEA VAR. BOTRYTIS) IN ARGHAKHANCHI, NEPAL

Reviews In Food And Agriculture ◽

10.26480/rfna.01.2020.12.17 ◽

2020 ◽

Vol 1 (1) ◽

pp. 12-17

Author(s):

Srijana Pandey ◽

Sapana Parajuli ◽

Biplov Oli ◽

Surya Dhungana

Keyword(s):

Brassica Oleracea ◽

Growth Parameters ◽

Block Design ◽

Leaf Length ◽

Growth And Yield ◽

Cost Ratio ◽

Benefit Cost Ratio ◽

Net Returns ◽

Benefit Cost ◽

Different Doses

The research was conducted at Beltari Sandhikharka-10, Arghakhanchi district to study about the effect of various doses of boron on growth and yield attributing characters of cauliflower (Brassica oleracea var. botrytis) during off-season from February to June in 2020. Five treatments; B0 (control/no application), B1: 2kg/ha, B2: 4kg/ha, B3: 6kg/ha, B4: 8kg/ha which are the different doses of boron application were laid out in Randomized Complete Block Design (RCBD) with 4 replications. The growth parameters like plant height, number of leaves per plant leaf length and leaf breadth of largest leaf were recorded multiple times with 15 days interval. Days to curd initiation and Days from curd initiation to harvest were recorded by regular field observation. The yield parameters; curd weight with leaves, Marketable curd weight, average curd yield, incidence of hollowing were recorded during harvest. The economics from application of boron doses in cauliflower production was obtained in terms of cost of cultivation, gross returns, net returns, and benefit cost ratio. The result showed that the growth and yield attributing characters of cauliflower were significantly affected by application of boron in which the value of these parameters was found significantly higher in B1 followed by other treatments. The average curd yield of cauliflower in B1 was found to be 12.39 mt/ha which was 48.92% higher than that of B0 with curd yield 8.32 mt/ha. Similarly, the net return was found significantly the highest in B1 and the lowest in B0. The result showed that application of boron in the range of 2-4 kg/ha is preferred to control and higher doses in respect of both productivity and economics.

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