The inability of gibberellic acid to stimulate amylase activity in pea cotyledons

Planta ◽  
1968 ◽  
Vol 82 (3) ◽  
pp. 299-301 ◽  
Author(s):  
Janet I. Sprent
Keyword(s):  
Gibberellic Acid ◽  
Amylase Activity

scholarly journals Amylase and acid phosphatase activity in potato tubers treated with gibberellic acid and stored at 2°C and 8°C

2015 ◽  
Vol 30 (1) ◽  
pp. 95-101 ◽  
Author(s):  
M. Bielińska-Czarnecka ◽  
K. Białek
Keyword(s):  
Acid Phosphatase ◽  
Gibberellic Acid ◽  
Phosphatase Activity ◽  
Acid Phosphatase Activity ◽  
Amylase Activity ◽  
Amylolytic Activity ◽  
Potato Tubers ◽  
Two Peaks

Amylase activity was higher in tubers stored at 2°C and mare marked in the soaked ones (both in water and in GA<sub>3</sub>). In the late and difficult-sprouting cv. Uran, sokaing resulted in increased amylolytic activity also at 8°C stored tubers. On the contrary, the acid phosphatase activity was a little higher at 8°C than at 2°C stored tubers. At the former temperature two peaks of activity were marked:, in November–December and February–March.

scholarly journals Hydroxyproline and proline inhibit α-amylase from isolated barley aleurone layers

2014 ◽  
Vol 52 (3-4) ◽  
pp. 253-263 ◽  
Author(s):  
Craig C. Freudenrich ◽  
William V. Dashek
Keyword(s):  
Carboxylic Acid ◽  
Hordeum Vulgare ◽  
Gibberellic Acid ◽  
Glutamic Acid ◽  
Incubation Medium ◽  
Amylase Activity ◽  
Membered Ring ◽  
Pipecolic Acid ◽  
Enzyme Substrate ◽  
Barley Aleurone

Previously, we reported that 1 mM hydroxyproline appeared to inhibit the gibberellic acid-induced release of α-amylase from isolated <em>Hordeum vulgare</em> L. cv. Himalaya aleurone layers into an incubation medium. Here, we report our attempts to determine the mechanism(s) for this inhibition and whether this inhibition can be caused by other proline analogues. Both 1 mM hydroxyproline and proline inhibited extracellular a-amylase activity without affecting its intracellular activity. This suggested that neither hydroxyproline nor proline impaired the release of a-amylase. Lineweaver-Burk plots revealed that both hydroxyproline and proline uncompetitively inhibited α-amy-lase. Thus, the inhibition is probably an assay artifact resulting from the formation of an enzyme-substrate-hydroxyproline or -proline complex. Because azetidine-2-carboxylic acid, glutamic acid and pipecolic acid did not inhibit extracellular α-amylase activity, the uncompetitive inhibition of a-amylase must be unique to imino aicids as well as their precursors and derivatives which possess a five membered ring.

Induction of Sensitivity to Gibberellic Acid in Developing Wheat Caryopses: Effect of Rate of Desiccation

1979 ◽  
Vol 6 (2) ◽  
pp. 229 ◽  
Author(s):  
PB Nicholls
Keyword(s):  
Relative Humidity ◽  
Gibberellic Acid ◽  
Incubation Medium ◽  
Amylase Activity ◽  
Dry Out

No change in the total β-amylase activity, attributable to the presence of 10-6 M gibberellic acid (GA3) in the incubation medium, was found in freshly harvested, de-embryonated, immature (11-38 days post-anthesis) caryopses of wheat. Significant amounts of GA3-induced α-amylase activity was found in 26-h incubates of similar caryopses which had been allowed to dry out either in the ear or detached from the ear. After 10 days of storage of detached immature caryopses in air of 99-100% relative humidity, de-embryonated half-caryopses responded to applied GA3 by producing α-amylase. More α-amylase was found in 26-h incubates if detached caryopses dried out slowly, but rapid desiccation led to little or no α-amylase being produced in the presence of GA3. Caryopses taken from ears cultured on 0.4 or 4% sucrose for 10 days did not respond to applied GA3 whereas those from ears cultured on water did respond, although the amount produced in 26-h incubates was not as large as those from slowly dried ears. Development of the ability to respond to GA3 by increasing α-amylase activity depended on the duration of desiccation or isolation from the plant. Changes in metabolism emanating from the interruption to the supply of sucrose to the caryopsis may be involved in the development of the ability of the aleurone to respond to GA3.

Regulation of starch and sugar levels in tobacco leaves by gibberellic acid

1969 ◽  
Vol 47 (10) ◽  
pp. 1595-1598 ◽  
Author(s):  
T. T. Lee ◽  
N. Rosa
Keyword(s):  
Gibberellic Acid ◽  
Reducing Sugars ◽  
Amylase Activity ◽  
Leaf Tissue ◽  
Tobacco Plants ◽  
Tobacco Leaves ◽  
Green Leaves ◽  
Specific Activities ◽  
Sugar Levels ◽  
Hydrolysis Of

Gibberellic acid (GA3) significantly reduced the level of starch in green leaves of tobacco plants. The total α-amylase activity and the specific activities of α-amylase and invertase were increased by GA3 treatment. Hydrolysis of starch during flue-curing contributed greatly to the increased level of reducing sugars in cured leaf tissue; decreasing the level of starch in green leaves by GA3 effectively lowered the level of reducing sugars after curing.

scholarly journals Action of gibberellic acid (GA3) on dormancy and activity of alpha-amylase in rice seeds

2002 ◽  
Vol 24 (2) ◽  
pp. 43-48 ◽  
Author(s):  
Antônio Rodrigues Vieira ◽  
Maria das Graças Guimarães Carvalho Vieira ◽  
Antônio C. Fraga ◽  
João Almir Oliveira ◽  
Custódio D. dos Santos
Keyword(s):  
Enzyme Activity ◽  
Gibberellic Acid ◽  
Seed Dormancy ◽  
Amylase Activity ◽  
Alpha Amylase ◽  
Rice Seed ◽  
Efficient Treatment ◽  
Soaking Time ◽  
Forced Air ◽  
Air Circulation

To evaluate the effectiveness of gibberellic acid (GA3) in breaking rice seed dormancy and the use of alpha-amylase enzyme activity as an indicator of the dormancy level, seed from the intensively dormant irrigated cultivar Urucuia were used. The seeds were submitted to a pre-drying process in a forced air circulation chamber under 40ºC during 7 days and submersed in 30 mL of GA3 solution under 0, 10, 30 and 60 mg/L H2O concentrations, during 2, 24 and 36 hours. After the treatments, the alpha-amylase activity was determined by using the polyacrilamide electrophoresis and spectrophotometry. At the same time, the germination test was made. The results indicated a gain in germination and in alpha-amylase activity in higher concentrations and soaking time of seeds in GA3. These observations support the conclusion that soaking seed in 60 mg GA3/L during 36 hours can be used as a quick and efficient treatment in breaking rice seed dormancy and is equivalent to the forced air circulation chamber at 40ºC during 7 days. The alpha-amylase enzyme activity proved to be as an efficient marker of the seeds dormancy level.

Extracts of the Brown Seaweed Ascophyllum nodosum Induce Gibberellic Acid (GA3)-independent Amylase Activity in Barley

2008 ◽  
Vol 27 (4) ◽  
pp. 370-379 ◽  
Author(s):  
Prasanth Rayorath ◽  
Wajahatullah Khan ◽  
Ravishankar Palanisamy ◽  
Shawna L. MacKinnon ◽  
Roumiana Stefanova ◽  
...  
Keyword(s):  
Gibberellic Acid ◽  
Amylase Activity ◽  
Brown Seaweed ◽  
Ascophyllum Nodosum

Susceptibility of naked oat cultivars to seed sprouting

2014 ◽  
Vol 9 (8) ◽  
pp. 823-832
Author(s):  
Andrzej Zieliński ◽  
Magdalena Simlat ◽  
Tomasz Wójtowicz ◽  
Maria Moś
Keyword(s):  
Abscisic Acid ◽  
Gibberellic Acid ◽  
Amylase Activity ◽  
Alpha Amylase ◽  
Falling Number ◽  
Total Rainfall ◽  
Naked Oat ◽  
Germination Time ◽  
Average Decrease ◽  
Oat Cultivars

AbstractThe production of economically important cereals is accompanied by the phenomenon of sprouting which in naked cultivars may limit their reproduction and usability. The objective of the work is to evaluate the susceptibility to sprouting in naked oat cultivars, and to test the usefulness of sprouting indices. In the years 2008–2010 for seeds of 8 cultivars, differing in the degree of sprouting damage, the coefficient of sprouting (Cs) was determined. Germinability (GF), dynamics (GD) and average germination time (GAT) were determined for seeds germinating in the presence of abscisic acid (ABA), gibberellic acid (GA3) and under control conditions. Basing on the falling number (FN) in consecutive days of the sprouting induction, alpha-amylase activity was determined. The highest values of Cs were found in 2008, the year with the highest total rainfall and temperature. In the presence of ABA the GF decreased by 21%, the GAT was 4.7 days longer, and the GD decreased by 55% compared with other substrates. An increase in alpha-amylase activity contributed to a 50%, on average, decrease in FN at 10°C and 30°C after 48 and 24 h of incubation, respectively. In the analyzed years the greatest resistance to sprouting was found for Bullion seeds.

Sign in / Sign up

Export Citation Format

Share Document