scholarly journals Gibberellic Acid Reverses Effects of Excess Paclobutrazol on Geranium

HortScience ◽  
1991 ◽  
Vol 26 (1) ◽  
pp. 39-40 ◽  
Author(s):  
Douglas A. Cox
Keyword(s):  
Gibberellic Acid ◽  
Growth Medium ◽  
Foliar Spray ◽  
Growth Suppression

Paclobutrazol (PBZ) was applied to `Mustang' geranium (Pelargonium × hortorum L.H. Bailey) as a single growth-medium drench at 0.06 mg a.i./pot or as a single foliar spray at 100 mg·liter-l when the plants had three to four expanded true leaves (34 days after sowing). At these rates, PBZ caused excessive growth suppression but plants flowered earlier than untreated controls. A single foliar spray of gibberellic acid (GA) at 100 mg·liter-l applied 0 (same day), 7, 14, or 21 days after PBZ reversed the growth suppression caused by PBZ. Plants treated with GA30 or 7 days after PBZ were as tall or taller and flowered at the same time as or later than the untreated (no PBZ, no GA3) controls. Plants treated with GA, 14 or 21 days after PBZ were shorter and flowered earlier than untreated controls but were taller than plants treated with PBZ alone. Response to GA3 was similar whether PBZ was applied as a drench or as a spray. Chemical name used: (+)-(R*,R*)-β([4-chlorophenyl]methyl)-α-(1,1-dimethylethyl)-1 H -1,2,4-triazole-1-ethanol (paclobutrazol).

Response of Apple Trees CV. Barwari to Foliar Spray With Iron and Gibberellic Acid 4 : Fruits Quality Parameters

2009 ◽  
Vol 13 (1) ◽  
pp. a1-a10
Author(s):  
مصلح محمد سعيد Ghafour ◽  
◽  
ازاد احمد الطيب Aziz ◽  
جاسم محمد علوان الاعرجي Almolla ◽  
◽  
...  
Keyword(s):  
Gibberellic Acid ◽  
Foliar Spray ◽  
Quality Parameters ◽  
Apple Trees

scholarly journals Interrelationships of Gibberellic Acid and Nitrate in Sugar Production and Enzyme Activity of Sugarcane

1969 ◽  
Vol 52 (1) ◽  
pp. 19-28
Author(s):  
Alex G. Alexander
Keyword(s):  
Enzyme Activity ◽  
Gibberellic Acid ◽  
Foliar Spray ◽  
Oxidative Enzymes ◽  
Sand Culture ◽  
Major Protein ◽  
Sucrose Synthesis ◽  
Sugar Production ◽  
Storage Tissue ◽  
Moderate Growth

Variable nitrate (NO3) and gibberellic acid (GA) were applied to sugarcane in order to clarify NO3-GA interrelationships which affect growth, sugar production, and enzyme activity. Since both low NO3 and foliar GA were known to increase sucrose synthesis as separate entities, their combination posed the following questions: 1, To what degree can NO3 be withheld before growth decline offsets sucrose gains? 2, To what extent will increasing NO3 supply offset the beneficial effects of GA application? 3, Is there a combination of high NO3 and GA which will permit both increased tonnage and increased sucrose synthesis as simultaneous effects? Healthy, 12-week-old plants grown in sand culture were treated for 5 weeks. Three levels each of NO3 (0, 5, and 30 meq./liter) and GA (0, 0.01-, and 0.10-percent solutions of foliar spray) were given in a 3 X 3 factorial combination. The following results were obtained: 1. Both NO3 and GA caused moderate growth increases as evidenced by fresh weights. A combination of high NO3 and medium GA gave the maximum yields recorded. Medium GA stimulated internode elongation while retaining stockiness of the cane. High GA caused excessive elongation plus weakening and occasional lodging of the plants. 2. High GA eliminated all NO3-induced growth increases. Withholding NO3 did not seriously curtail growth so long as GA was applied. Plants given GA without NO3 grew comparably to those receiving high NO3 without GA. 3. Withholding NO3 caused major sucrose increases in both leaf and immature storage tissues. Raising NO3 increased synthesis of total ketoses but caused striking decline of sucrose. GA caused significant sucrose increases in storage tissue when NO3 supply was low. However, GA-induced sucrose increases could not offset sucrose losses due to high NO3. 4. The most favorable treatment for growth and sugar production was a combination of low NO3 and medium GA. This induced moderate growth plus major sucrose increases. 5. Leaf phosphatase and ATP-ase were greatly stimulated by NO3. High GA alleviated the NO3 effects. 6. A strong NO3 X GA interaction affected both hydrolytic and oxidative enzymes in immature storage tissue. Phosphatase, ATP-ase, peroxidase and polyphenol oxidase were all involved. 7. NO3 greatly increased protein content of immature storage tissue, but GA had little effect. GA was able to stimulate both growth and sugar formation without the major protein changes characteristic of NO3 treatments. Practical usage of the NO3 and GA data are discussed. It is felt that GA treatment should be delayed after heavy nitrogen fertilization, and will not prove fully effective if given simultaneously with normal fertilizer programs.

scholarly journals Effect of foliar spray of GA3 and NAA on sex expression and yield of bitter gourd

2019 ◽  
Vol 44 (2) ◽  
pp. 281-290
Author(s):  
R Khatoon ◽  
M Moniruzzaman ◽  
M Moniruzzaman
Keyword(s):  
Gibberellic Acid ◽  
Block Design ◽  
Foliar Spray ◽  
Sex Expression ◽  
Fruit Weight ◽  
Fruit Yield ◽  
Bitter Gourd ◽  
Yield Attributes ◽  
Randomized Complete Block Design ◽  
Male Flowers

A field experiment was conducted at the Plant Physiology field of Horticulture Research Center, BARI, Gazipur during two consecutive years of kharif 2014 and 2015 to assess the effect of GA3 and NAA on sex expression, yield and yield components of bitter gourd (Momordica charantia L.) var. BARI Karola-1. Eeleven treatments comprising five concentrations each of gibberellic acid (50, 100, 150, 200 and 300 ppm) and naphthalene acidic acid (50, 100, 150, 200 and 300 ppm) along with distilled water considered as control were evaluated in randomized complete block design with three replications. Gibberellic acid (GA3) and Naphthalene acidic acid (NAA) were sprayed at 4 leaf stage; second spray was done at 35-38 DAS and third spray done at flowering stage. All the treatments improved the flowering and yield characters over control. Foliar spray of NAA @ 150 ppm and 200 ppm was found better in terms of sex expression, yield and yield attributes of bitter gourd as compared to control and other treatments. Spray of NAA @ 150 ppm gave the lowest number of male flowers and the highest number of female flowers thereby produced the lowest sex ratio (male:female). Number of fruits/plant, individual fruit weight and fruit yield/plant were also found maximum from NAA 150 ppm. Maximum fruit yield was recorded with the application of NAA @ 150 ppm. Spraying of NAA @ 150 ppm gave the maximum gross return and net return with the highest BCR of 3.17. Bangladesh J. Agril. Res. 44(2): 281-290, June 2019

EFFECT OF FOLIAR SPRAYS OF GIBBERELLIC ACID ON NODULE NUMBER SHOOT AND ROOT LENGTH OF PHASEOLUS ACONITIFOLIUS

2018 ◽  
Vol 24 (1) ◽  
Author(s):  
SUSHIL KUMAR
Keyword(s):  
Gibberellic Acid ◽  
Root Length ◽  
Foliar Spray ◽  
Nodule Number ◽  
Foliar Sprays ◽  
Maximum Inhibition

The effect of foliar spray of gibberellic acid on nodule number, shoot and root length was studied. Gibberellic acid inhibited the number of nodules at all the three concentrations. Maximum inhibition in the number of nodule was noted at 100 ppm concentration whereas the shoot and root length showed better growth.

Gibberellic acid induced growth acceleration in Populus hybrids

1984 ◽  
Vol 14 (6) ◽  
pp. 850-854 ◽  
Author(s):  
S. B. Rood ◽  
G. Daicos ◽  
T. J. Blake
Keyword(s):  
Gibberellic Acid ◽  
Leaf Area ◽  
Foliar Spray ◽  
Dry Weight ◽  
Height Growth ◽  
Total Leaf Area ◽  
Leaf Production ◽  
Relative Growth ◽  
Shoot Dry Weight ◽  
Net Assimilation

Weekly applications of 0.4 mg gibberellic acid (GA) in 8 μL 95% ethanol micropipetted onto shoots of rooted cuttings increased Populuseuramericana (Dode) Guinier height growth by 54% and shoot dry weight by 25% after 21 days. Total leaf area increased by 21% as a result of more rapid leaf production and slightly larger leaf sizes. Root growth was unaffected by GA treatment. The observed GA-induced acceleration resulted from an increase in relative growth rate while mean net assimilation rate was unaffected. Owing to a substantial increase in the number and size of leaves, the leaf area ratio, representing the ratio of photosynthesizing to respiring material, increased. While direct micropipette application of GA promoted height growth and primary shoot dry weight accumulation, GA application through either foliar spray or soil drench also promoted the growth of secondary shoots. Application of GA to shoots was more effective in promoting shoot growth than application through the roots. Direct GA application also promoted the growth of P. alba L. × P. grandidentata Michx. and P. × canescens (Ait.) Smith × P. alba × P. grandidentata. Thus, GA can be used for hastening early growth of these trees under winter greenhouse conditions.

scholarly journals Effects of Foliar Application of Gibberellic Acid on the Salt Tolerance of Tomato and Sweet Pepper Transplants

Horticulturae ◽  
2020 ◽  
Vol 6 (4) ◽  
pp. 93
Author(s):  
Alessandro Miceli ◽  
Filippo Vetrano ◽  
Alessandra Moncada
Keyword(s):  
Salt Stress ◽  
Salt Tolerance ◽  
Gibberellic Acid ◽  
Foliar Application ◽  
Saline Water ◽  
Foliar Spray ◽  
Sweet Pepper ◽  
Limiting Factor ◽  
Growth Stages ◽  
Promoting Effect

Seed germination and early seedling growth are the plant growth stages most sensitive to salt stress. Thus, the availability of poor-quality brackish water can be a big limiting factor for the nursery vegetable industry. The exogenous supplementation of gibberellic acid (GA3) may promote growth and vigor and counterbalance salt stress in mature plants. This study aimed to test exogenous supplementation through foliar spray of 10−5 M GA3 for increasing salt tolerance of tomato and sweet pepper seedlings irrigated with increasing salinity (0, 25, and 50 mM NaCl during nursery growth. Tomato and sweet pepper seedlings suffered negative effects of salinity on plant height, biomass, shoot/root ratio, leaf number, leaf area, relative water content, and stomatal conductance. The foliar application of GA3 had a growth-promoting effect on the unstressed tomato and pepper seedlings and was successful in increasing salinity tolerance of tomato seedlings up to 25 mM NaCl and up to 50 mM NaCl in sweet pepper seedlings. This treatment could represent a sustainable strategy to use saline water in vegetable nurseries limiting its negative effect on seedling quality and production time.

scholarly journals CAN PHYTOHORMONES STIMULATE INITIAL GROWTH OF BRAZILIAN SAVANNA TREES?

Heringeriana ◽  
2018 ◽  
Vol 11 (2) ◽  
pp. 1-12
Author(s):  
Luisa Vieira B. Soares ◽  
Sarah Christina Caldas Oliveira ◽  
Letícia Regina Braga ◽  
Alexandre Bonesso Sampaio ◽  
Isabel Belloni Schmidt
Keyword(s):  
Gibberellic Acid ◽  
Tree Species ◽  
Large Scale ◽  
Foliar Spray ◽  
Shoot Biomass ◽  
Initial Growth ◽  
Crop Species ◽  
Repeated Use ◽  
Native Tree Species ◽  
Control Water

The initial growth of Cerrado tree species is slow, what impairs large scale seedling production for planting. The effect of plant hormones is well known for crop species, in this study we aimed to test the effect of two commercial biostimulants on the initial growth of six native tree species widely distributed and abundant in Cerrado. We applied nine treatments using foliar spray: T0 – control (water); commercial Progibb® (gibberellic acid) T1 – 0,8 mL.L-1; T2 – 1,6 mL.L-1; T3 – 2,4 mL.L-1 and T4 – 3,2 mL.L-1; commercial Stimulate® (gibberellic acid, cytokinin and auxin): T5 – 6,0 mL.L-1; T6 – 8,0 mL.L-1; T7 – 12,0 mL.L-1; T8 – 18,0 mL.L-1 and T9 – 24,0 mL.L-1. We measured plant height and diameter every other week and recorded root and shoot biomass and leaf area after 111 growing days. No treatment significantly increased plants’ initial growth, which may only happen after higher and/or repeated use of these two biostimulants, especially Progibb® for Anacardium humile and Jacaranda cuspidifolia and Stimulate® for Hymenaea stignocarpa and Copaifera langsdorfii.

scholarly journals Effects of Rate and Repeat Application of Flurprimidol on the Growth of Photinia × fraseri and Ilex crenata ‘Compacta’

1988 ◽  
Vol 6 (4) ◽  
pp. 114-118
Author(s):  
Adolph J. Laiche
Keyword(s):  
Growth Medium ◽  
Shoot Growth ◽  
Foliar Spray ◽  
Growing Season ◽  
Plant Size ◽  
Foliar Sprays ◽  
Landscape Plants ◽  
Low Concentrations ◽  
Leaf Distortion ◽  
Test Plants

Flurprimidol, α-(1-Methylethyl)-α-[4-(trifluoromethoxy)phenyl]-5-pyrimidine-methanol, was applied to three month plants of Photinia × fraseri in 5.6 L (6 qt) containers and Ilex crenata ‘Compacta’ in 2.8 L (3 qt) containers as foliar sprays at 0, 33, 66, 132, 264, 528, 1056, 2112, 4224, and 8448 ppnl. Growth-medium drench applications with flurprimidol were applied at 0, 2, 4, 8, 16, 32, 64, 128, 256, and 512 ppm solution, 0.5 L (17 oz) per 5.6 L (6 qt) container to Photinia. The initial foliar spray treatments and the growth medium drench treatments were applied on July 14, 1983. All test plants were planted in soil on December 9, 1983. Foliar spray treatments were repeated on July 19, 1985. Flurprimidol at low concentrations as a spray and drench substantially reduced plant size with little or no phytotoxicity. Duration of growth suppression increased as rate increased. Flurprimidol at low rates reduced growth for the remainder of the growing season in which it was applied. At higher rates growth was also reduced in the following growing season. Minor leaf distortion of smaller leaves was obtained at low rates and leaf distortion appeared to increase slightly at higher rates. Shoot growth after the effects of flurprimidol were no longer apparent appeared normal. Results indicate that flurprimidol alone and in conjunction with pruning can be helpful in maintaining woody landscape plants to a desirable size.

scholarly journals Investigation of improving the drought tolerance in persian petunia (Petunia sp.) by exogenous application of salicylic acid and gibberellic acid

2021 ◽  
Vol 20 (1) ◽  
pp. 37-48
Author(s):  
Morteza Goldani ◽  
Ali Dolatkhahi ◽  
Mahdi Parsa ◽  
Navid Vahdati ◽  
Zahra Rasouli
Keyword(s):  
Salicylic Acid ◽  
Water Stress ◽  
Stomatal Conductance ◽  
Gibberellic Acid ◽  
Water Deficit ◽  
Abiotic Stress Tolerance ◽  
Foliar Spray ◽  
Field Capacity ◽  
Exogenous Application ◽  
Four Levels

Plants respond to water deficit through several mechanisms. Among which, plant hormones play an important role in induction to abiotic stress tolerance. To bring this issue closer, an experiment was conducted to examine whether salicylic acid (SA) and gibberellic acid (GA3) exogenous applications through foliar spray could alleviate detrimental effects of water deficit on Persian petunia. Treatments consisted of water stress in three levels: 100% field capacity (F.C.) as control, 50, and 25% F.C linked with different concentrations of GA3 and SA sprayed at four levels (0, 100, 200 and 300 mg L–1). Results showed that the dry and fresh biomass, leaf area, photosynthetic pigments levels, relative water content (RWC) and the total number of flowers were significantly (P≤0.01) reduced in response to water deficit. However, free proline concentration and root-to-shoot ratio significantly increased in stressed plants. Plants subjected to severe water stress (25% F.C.), exhibit about 66% stomatal conductance rate lower than the plants grown at 100% F.C. The results showed that SA-treated plants exhibited reduced negative effect of water stress on most of the qualitative and quantitative attributes compared to control, while GA3 application had little impact on studied traits. Importantly, stomatal conductance and RWC were improved in water-stressed plants treated with SA. Moreover, SA-treated plants produced more flowers at all water deficit levels compared to GA3 sprayed plants. It can be concluded that Persian petunia plants respond to water deficit through adaptive changes at biochemical and morphological levels and that adverse effects of water deficit could be alleviated by exogenous application of SA.

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