Effect of Growth Regulators on Stomatal Structure and Development in the Cotyledons of Lagenaria leucantha (Duch.) Rusby

1975 ◽  
Vol 23 (1) ◽  
pp. 13 ◽  
Author(s):  
JA Inamdar ◽  
M Gangadhara
Keyword(s):  
Growth Regulators ◽  
Growth Inhibitor ◽  
Guard Cells ◽  
Inhibitory Effect ◽  
Subsidiary Cell ◽  
Growth Promoter ◽  
Stomatal Index ◽  
Stomatal Frequency ◽  
Growth Promoters ◽  
High Concentration

In untreated cotyledons (controls) anomocytic stomata and stomata with a single subsidiary cell were observed. In cotyledons treated with growth regulators, anisocytic, paracytic, cyclocytic and several abnormal stomatal types were observed in addition to those found in the controls. Gibberellic acid, though a growth promoter, acted as an inhibitor at high concentration. Ascorbic acid at 25 p.p.m. increased the stomatal index and the size of guard cells, while the stomatal frequency decreased. Sucrose at 2000 p.p.m. increased the stomatal index and the length of guard cells. 2,3,5-Tri-iodobenzoic acid caused degeneration of guard cells and acted as a growth inhibitor at higher concentrations. As the concentration of kinetin increased, decreases in the stomatal frequency, index and size of guard cells were noted. Kinetin also induced the formation of contiguous stomata and the division of guard cells. Sulphanilamide could act either as an inhibitor or as a promoter as its concentration increased. Coumarin at 50 p.p.m. reduced the size of guard cells and the stomatal frequency, and commonly induced persistent stomatal initials, while at 100 p.p.m. only the radicle emerged and the cotyledons failed to emerge from the seed-coat. Increased concentrations of colchicine promoted more induction of persistent stomatal initials, and inhibited stomatal formation as was evidenced by a reduced stomatal frequency and index. Colchicine at 50 p.p.m. induced formation of double pores in a stoma, abnormally large pore sizes, and increases in the size of guard cells and their nuclei. With maleic hydrazide the sizes of guard and epidermal cells were reduced and persistent stomatal initials occasionally formed. Growth promoters could sometimes interact with inhibitors to overcome their inhibitory effect, depending on the substances used in combination and their concentrations.

scholarly journals Detecting Endogenous Growth Regulators on the Sarcotesta, Sclerotesta, Endosperm, and Embryo by Paper Chromatography on Fresh and Old Seeds of Two Papaya Varieties

1969 ◽  
Vol 64 (2) ◽  
pp. 164-172
Author(s):  
Manuel N. Reyes ◽  
Agripino Pérez ◽  
José Cuevas
Keyword(s):  
Endogenous Growth ◽  
Paper Chromatography ◽  
Growth Regulators ◽  
Growth Inhibitor ◽  
Natural Growth ◽  
Growth Inhibitors ◽  
Growth Promoters ◽  
Gelatinous Envelope ◽  
Papaya Seeds

Sarcotesta, sclerotesta, endosperm and embryo of fresh and old (0 and 3 years, respectively) seeds of the P.R. 6-65 and P.R. 8-65 papaya varieties were separately analyzed by paper chromatography to determine the presence of natural growth inhibitor that might be responsible for the reduction in germination of papaya seeds during storage. The results showed that in the innermost seed parts (embryo and endosperm) endogenous growth promoters were found while the outermost structures (sarcotesta and sclerotesta) contained inhibitors. Therefore, it is possible that the natural growth inhibitors of this seed might be minimized by removing the sarcotesta (the gelatinous envelope) of the seed, which contains the most endogenous growth inhibitors, plus a careful washing to eliminate the soluble inhibitors of the sclerotesta during the extraction of seeds from the fruits.

A Leaf Elongation Assay Detects an Unknown Growth Inhibitor in Xylem Sap From Wheat and Barley

1992 ◽  
Vol 19 (2) ◽  
pp. 127 ◽  
Author(s):  
R Munns
Keyword(s):  
Abscisic Acid ◽  
Growth Regulators ◽  
Saline Soil ◽  
Xylem Sap ◽  
Growth Inhibitor ◽  
Leaf Expansion ◽  
Growth Promoter ◽  
Inhibitory Substance ◽  
Leaf Elongation ◽  
Transpiration Stream

Recent research suggests that chemicals sent from roots in the transpiration stream could control leaf expansion, and that xylem sap from plants in dry or saline soil could contain increased amounts of a growth inhibitor, or decreased amounts of a growth promoter. In order to test these possibilities, a bioassay that could detect the presence of growth regulators in xylem sap was developed using whole shoots of wheat and barley seedlings. The bioassay showed that xylem sap collected from intact, transpiring plants in a drying soil contained a strong growth inhibitor. The inhibitory substance was not abscisic acid: while the concentration of abscisic acid in the sap rose as the soil dried, the highest concentration found, 4 × 10-8 M, was too low to inhibit leaf expansion. The identity of the new inhibitor is unknown.

scholarly journals The effect of 2,4-D and ABA on respiration of isolated mitochondria from maize coleoptiles

2014 ◽  
Vol 53 (3) ◽  
pp. 363-376
Author(s):  
Ewa Raczek
Keyword(s):  
Oxidative Phosphorylation ◽  
Growth Regulators ◽  
Growth Inhibitor ◽  
Inhibitory Effect ◽  
Similar Response ◽  
Mitochondrial Membranes ◽  
Oxidative Potential ◽  
Succinate Oxidation ◽  
Uncoupling Of Oxidative Phosphorylation ◽  
2,4 Dichlorophenoxyacetic Acid

The susceptibility of isolated maize mitochondria to the growth regulators: 2,4-dichlorophenoxyacetic acid (2,4-D) and abscisic acid (ABA) was studied. It was found that 2,4-D (a herbicide) inhibits respiration in mitochondria, as do other herbicides or phenoxy-acids. In the entire range of concentrations used (10<sup>-3</sup>-10<sup>-9</sup> M), 2,4-D introduced into the medium before the respiration reaction was begun, or during it, limited the intensity of succinate oxidation. It did not, however, markedly change phosphorylation properties. Uncoupling of oxidative phosphorylation took place only after preincubation of mitochondria with 2,4-D and was the result of the destruction of mitochondrial membranes. ABA (a growth inhibitor of plants) caused a similar response in maize mitochondria. Preincubation of mitochondria with ABA lead to the uncoupling of oxidative phosphorylation. Whereas ABA introduced during respiration (state 4 respiration) or before its onset, lowered the oxidative potential of mitochondria, it also changed the pattern of state 4-3-4 transition after addition of ADP (it was especially visible at high concentrations), which indicates that the coupling of oxidative phosphorylation with the respiratory chain has faltered. It seems that this negative effect of 2,4-D and ABA on respiration of isolated maize mitochondria is connected with the inhibitory effect of these growth regulators on the growth of maize coleoptiles. Interference in the organization mitochondrial membranes results in a lowered supply of ATP - a source of energy needed in elongation processes.

Measurement of the Platelet Response to Laser- induced Microvascular Injury

1974 ◽  
Vol 32 (02/03) ◽  
pp. 704-713 ◽  
Author(s):  
F. N McKenzie ◽  
K.-E Arfors ◽  
N. A Matheson
Keyword(s):  
Inhibitory Effect ◽  
Microvascular Blood Flow ◽  
Platelet Response ◽  
High Concentration ◽  
Platelet Activity ◽  
Microvascular Injury ◽  
Arterial Blood ◽  
Proximal Site ◽  
Adenosine Phosphates

SummaryA study has been made of the biochemical factors underlying the platelet response to laser-induced microvascular injury. A platelet aggregating substance is produced at sites of laser-induced injury which markedly stimulates platelet activity at a site of injury inflicted a short distance downstream. Distal sites of injury are not similarly influenced if the distance between the injuries is increased or if the proximal site no longer shows platelet-stimulating activity. The stimulating effect of an adjacent proximal injury on platelet activity at a distal site is inhibited by local intra-arterial infusion of adenosine. Measurements of arterial blood pressure and microvascular blood flow velocity during adenosine infusion showed that its inhibitory effect on platelet activity is largely independent of its vasodilator properties. The effect of infusion of different adenosine phosphates (AMP, ADP, ATP) was also studied. Very small amounts of ADP markedly stimulated platelet activity and the emboli formed were similar to those normally produced at sites of laser injury. At high concentration AMP inhibited while ATP stimulated platelet activity in vivo. The results emphasise the fundamental role of ADP as a mediator of the platelet response at sites of laser- induced microvascular injury.

scholarly journals Performance of some growth promoters on hybrid walking catfish (Clarias batrachus × Clarias gariepinus)

2017 ◽  
Vol 3 (1) ◽  
pp. 103-108
Author(s):  
Md Sirazul Islam ◽  
M Mamnur Rashid ◽  
Mohammad Shamsul Arefin ◽  
Pronab Naha ◽  
Md Rokanuddula
Keyword(s):  
Weight Gain ◽  
Control Diet ◽  
Animal Health ◽  
Clarias Gariepinus ◽  
Survival Rates ◽  
Clarias Batrachus ◽  
Daily Weight Gain ◽  
Growth Promoter ◽  
Average Daily Weight Gain ◽  
Growth Promoters

A study was conducted to determine the efficacy of three most commonly used growth promoters from different pharmaceutical companies on growth performance of hybrid walking catfish (Clarias batrachus × Clarias gariepinus). The experiment was done in the wet laboratory of the Department of Aquaculture, BAU, Mymensingh, with a total of 10 aquaria and 160 fish having mean initial weight of 6.3 ± 0.48 g. The three growth promoters, “Charger gel” from Fishtech (BD) Ltd., “Growth gel” from Advance Agrotech (BD) Ltd. and “Hepaprotect-aqua” from Renata Animal health Ltd., were used in separate nine (9) aquaria at recommended, lower dose and higher dose respectively. One aquarium was used as control (diet without any growth promoter). The fish were fed with paragon nursery floating feed at 20% of body weight in each aquarium for 28 days. Doses of Charger gel were given as 80, 60 and 100 mg/20 g feed/day, that of Growth gel, 0.14, 0.12 and 0.16 ml/20 g feed/day and of Hepaprotect-aqua, 30, 15 and 50 mg/20 g feed/day. Re-circulatory system was used throughout the experimental period. By applying recommended, lower and higher dose of “Charger gel”, mean final weights were found as 23.0, 21.9 and 35.9 g; average daily weight gain as 0.60, 0.56 and 1.06 g and specific growth rate (SGR) as 2.01, 1.93 and 2.70% respectively. For “Growth gel”, mean final weights were found as 22.8, 17.3 and 31.1 g; average daily weight gain as 0.59, 0.39 and 0.88 g and SGR as 1.99, 1.57 and 2.48 % respectively. For “Hepaprotect-aqua”, mean final weights were found as 24.2, 17.5 and 28.2 g; average daily weight gain as 0.64, 0.40 and 0.78 g and SGR as 2.09, 1.58 and 2.32% respectively. In all the cases survival rates were 100%. All the three growth promoters showed better results at their higher doses in comparison to their results in lower and recommended doses. However, in average Charger gel showed the best result than the other two growth promoters. This information on the efficacy study of growth promoters needs to be disseminated to the farmers for improved fish production.Asian J. Med. Biol. Res. March 2017, 3(1): 103-108

Growth-Inhibiting Properties of Xylem Exudate From Vitis vinifera

1995 ◽  
Vol 22 (1) ◽  
pp. 7 ◽  
Author(s):  
JA Campbell ◽  
BR Loveys ◽  
VWK Lee ◽  
S Strother
Keyword(s):  
Vitis Vinifera ◽  
Inhibitory Activity ◽  
Lemna Minor ◽  
Growth Inhibitor ◽  
Inhibitory Effect ◽  
Vitis Vinifera L ◽  
Inhibitory Effects ◽  
Inhibitor Activity ◽  
Xylem Exudate ◽  
Growth Inhibiting

An inhibitory effect on the growth of Lemna minor L. cultures has been demonstrated in xylem exudate from Vitis vinifera L. var. Waltham Cross bled from canes cut near the time of budburst. Most inhibitory activity was detected up to the time of maximal daily exudation, which corresponded closely with budburst. After this time the inhibitory activity rapidly disappeared. A similar pattern occurred in each of the 3 years of the study, 1988-1990. Using ultrafiltration, it was shown that most of the growth inhibitor activity of the crude exudate was located in the 0.5-10 kDa fraction. This fraction exhibited a seasonal variation in its bioactivity similar to that ofthe crude exudate samples. The 0.5-10 kDa fraction was found to contain abscisic acid but not in a sufficient quantity to account for the inhibitory effects. When chromatographically separated fractions corresponding to oligosaccharides were pooled, biological activity equivalent to that of the crude exudate was retained, which provides evidence that the inhibitor is possibly an oligosaccharide.

Evaluation of the corrosion behavior of AZ31 magnesium alloy with different protein concentrations

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yucong Ma ◽  
Mohd Talha ◽  
Qi Wang ◽  
Zhonghui Li ◽  
Yuanhua Lin
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Electrochemical Impedance ◽  
Surface Film ◽  
Energy Dispersive Spectrometer ◽  
Inhibitory Effect ◽  
Corrosion Process ◽  
High Concentration ◽  
Content Type ◽  
Atomic Force

Purpose The purpose of this paper is to study systematically the corrosion behavior of AZ31 magnesium (Mg) alloy with different concentrations of bovine serum albumin (BSA) (0, 0.5, 1.0, 1.5, 2.0 and 5.0 g/L). Design/methodology/approach Electrochemical impedance spectroscopy and potential dynamic polarization tests were performed to obtain corrosion parameters. Scanning electrochemical microscopy (SECM) was used to analyze the local electrochemical activity of the surface film. Atomic force microscope (AFM), Scanning electron microscope-Energy dispersive spectrometer and Fourier transform infrared spectroscopy were used to determine the surface morphology and chemical composition of the surface film. Findings Experimental results showed the presence of BSA in a certain concentration range (0 to 2.0 g/L) has a greater inhibitory effect on the corrosion of AZ31, however, the presence of high-concentration BSA (5.0 g/L) would sharply reduce the corrosion resistance. Originality/value When the concentration of BSA is less than 2.0 g/L, the corrosion resistance of AZ31 enhances with the concentration. The adsorption BSA layer will come into being a physical barrier to inhibit the corrosion process. However, high-concentration BSA (5.0 g/L) will chelate with dissolved metal ions (such as Mg and Ni) to form soluble complexes, which increases the roughness of the surface and accelerates the corrosion process.

Allelopathic Potency and an Active Substance from Hairy Vetch

2020 ◽  
Author(s):  
Weihong Sun ◽  
Guofeng Yang ◽  
Lili Cong ◽  
Juan Sun ◽  
Lichao Ma
Keyword(s):  
Seed Germination ◽  
Seedling Growth ◽  
Root Length ◽  
Leaf Extract ◽  
Growth Inhibitor ◽  
Inhibitory Effect ◽  
Allelopathic Effect ◽  
Coumaric Acid ◽  
Hairy Vetch ◽  
Allelopathic Effects

Background: Plant allelopathy refers to the release of chemicals from plants or microorganisms into the environment, may have direct or indirect, beneficial or harmful effects on other plants or microorganisms. When plants grow in an unfavorable environment,more allelochemicals will be secreted and the expression of allelopathic effects will increase, giving plants a certain competitive advantage. Hairy vetch is one of the most promising allelopathic crops and the aqueous extract of hairy vetch has an inhibitory effect on the root length and seedling height of grass crops. The current study aimed to study the allelopathic effect of hairy vetch on alfalfa, and exploring an ecological method to remove the root system of alfalfa.Methods: In this experiment, the allelopathic effects of the seeds, stems and leaves, roots extracts and root exudates (0, 3, 6, 9 and 12 mg·mL-1) on the seed germination and seedling growth of alfalfa were evaluated. And the main allelopathic substances from the stem and leaf extract were isolated and identified using high performance liquid chromatography- mass spectrometry (HPLC-MS).Result: The results showed that all of the extracts can inhibit alfalfa seed germination and seedling growth and stem and leaf extract had the strongest inhibitory effect, especially for inhibiting the root growth. A main allelochemical substance, o-coumaric acid, was screened out and the root length of alfalfa was completely inhibited at 1.6 mg·mL-1 of o-coumaric acid. The findings of these experiments show hairy vetch has strong allelopathic effect on alfalfa and o-coumaric acid is a chemical growth inhibitor.

Effect of Plant Growth Regulators on Growth and Quality Flower Production of Chrysanthemum (Chrysanthemum Indicum L.)

2022 ◽  
Vol 2 (1) ◽  
pp. 10-18
Author(s):  
Md Ehsanullah ◽  
Ahasan Ullah Khan ◽  
Md Kamruzzam ◽  
Sarah Tasnim
Keyword(s):  
Plant Growth ◽  
Plant Growth Regulators ◽  
Growth Regulators ◽  
Block Design ◽  
Research Centre ◽  
Vase Life ◽  
Flower Initiation ◽  
Growth Promoter ◽  
Flower Production ◽  
Minimum Number

A field study was conceded to assess the effect of plant growth regulators on growth and quality flower production of chrysanthemum at Horticulture Research Centre (HRC), Gazipur, Bangladesh. The experiment was laid out in Randomized Complete Block Design (RCBD) with ten (10) treatments and three replications. The treatments of plant growth regulators concentration were T1-50 ppm GA3, T2-100 ppm GA3, T3-150 ppm GA3, T4-400 ppm CCC, T5-600 ppm CCC, T6-800 ppm CCC, T7-250 ppm MH, T8-500 ppm MH, T9-750 ppm MH and, T10-Control. The maximum spreading of plant (27.0 cm) was observed when plants were treated with GA3 @ 150 ppm where the minimum plant spread (16.8 cm) was recorded in plants treated with CCC @ 800 ppm. The higher number of suckers (33) per pot was produced when pots were treated with GA3 @ 150 ppm whereas, application of CCC at three different concentrations produced lower number of suckers.  The highest number of flower (40) was recorded with 150 ppm GA3, where minimum number of flowers (25) per pot in 800 ppm CCC. The plants sprayed with 50 ppm GA3 took 48 days to flower initiation, whereas, it took 70 days with 750 ppm MH. the highest plants recorded (7.40 cm) with 800 ppm CCC, whereas, lowest size (6.50 cm) was obtained with the application of 500 ppm MH. The maximum vase life of flowers was recorded for the treatment 800 ppm CCC (15 days), which was at par with 13 days vase life obtained by spraying 600 ppm CCC. Therefore, it is concluded that the GA3 acted as growth promoter and the CCC acted as growth retardants on yield and quality of chrysanthemum.

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