Gibberellic acid

About: Gibberellic acid is a research topic. Over the lifetime, 6597 publications have been published within this topic receiving 109294 citations. The topic is also known as: GIBBERELLIN A3.

Gibberellin-Auxin Interaction in Pea Stem Elongation

Abstract: Joint application of gibberellic acid and indole-3-acetic acid to excised stem sections, terminal cuttings, and decapitated plants of a green dwarf pea results in a markedly synergistic growth response to these hormones. Synergism in green tall pea stem sections is comparatively small, although growth is kinetically indistinguishable from similarly treated dwarf sections.Gibberellin-induced growth does not appear to be mediated through its effect on auxin synthesis, since gibberellin pretreatment of dwarf cuttings fails to elicit an enhanced tryptophan-induced growth response of sections, whereas auxin-induced growth is strongly enhanced. Also, tryptophan-gibberellin synergism is not significant in sections and cuttings of green dwarf peas, while auxin-gibberellin synergism is.Administration of gibberellic acid prior to indole-3-acetic acid results in greatly increased growth. In reversed order, the application fails to produce any synergistic interaction. This indicates that gibberellin action must precede auxin action in growth regulation.

Fruit growth, firmness and cell wall hydrolytic enzyme activity during development of sweet cherry fruit treated with gibberellic acid (GA3)

Abstract: SummaryFour genotypes of sweet cherry (Prunus avium L.) producing fruits characterized as early season/soft texture (`Merpet'), early season/firm texture (`Celeste'), late season/soft texture (13S-27-17) and late season/firm texture (`Lapins') were evaluated for differences in fruit growth, firmness, and hydrolytic enzyme activity with or without gibberellic acid treatment. The fruit developed in three distinct stages after fertilization corresponding to the standard Prunus profile (i.e. cell division, lag phase, cell enlargement). Fruits on early maturing genotypes had a shortened period in the lag phase compared to the late maturing cultivars. Fruit firmness in all genotypes increased from the earliest green-coloured stage (about 5.mm in fruit diameter) until the middle of the lag phase, then decreased rapidly and continuously from that stage throughout maturation. Application of 20 mg l-1 GA3 increased fruit firmness at harvest, decreased the rate of fruit softening and delayed fruit maturity 5±8.d for...

Relation between relative growth-rate, endogenous gibberellins, and the response to applied gibberellic-acid for plantago-major

Abstract: Relationships between relative growth rate (RGR), endogenous gibberellin (GA) concentration and the response to application of gibberellic acid (GA(3) ) were studied for two inbred lines of Plantago major L., which differed in RGR. A4, the fast-growing inbred line, had a higher free GA concentration than the slow-growing W9, as analyzed by enzyme immunoassay. GA(3) application increased total plant weight and RGR(3) particularly for the slow-growing line. Chlorophyll a content and photosynthetic activity per unit leaf area were decreased, while transpiration rate was unaffected by GA(3) application. The increase in RGR by GA(3) application was associated with an increased leaf weight ratio; specific leaf area and percentage of dry matter in the leaves were only temporarily affected. Root respiration rate per unit dry weight was unaffected. The correlation between low RGR, low GA concentration and high responsiveness to applied GA(3) supports the contention that gibberellins are involved in the regulation of RGR. However, the transient influence of GA(3) application on some growth components suggests the involvement of other regulatory factors in addition to GA.

Effect of Acetylsalicylic Acid, Indole-3- Bytric Acid and Gibberellic Acid on Plant Growth and Yield of Pea (Pisum Sativum L.)

Abstract: 1 Abstract: Pots experiment were conducted during the two successive seasons of 2007 and 2008 to investigate the effect of acetylsalicylic acid (ASA) at 10 and 20 ppm, indole-3-bytric acid (IBA) at 3 50and 100 PPM and gibberellic acid (GA ) at 50 and 100 PPM on pea (Pisum sativum L.) cv Prgress mog. Growth regulators were applied as foliar spray at 25 and 35 days after sowing. Three samples were taken at 21, 45 and 70days after sowing coinciding with vegetative stage, flowering and harvest respectively. Application of ASA and IBA enhanced plant growth as indicated by plant height, number of leaves, fresh and dry weights in both seasons. Significant increase in 1000 seeds weight and pod parameters (length of pod, pods number / plant, seeds number / pod, pods fresh and dry weights) was 3 recorded by ASA and IBA at harvest comparing with control and GA treated plants. These positive effects of ASA and IBA were correlated with significant increase in total chlorophylls in leaves, total soluble proteins, praline, phenol, total soluble carbohydrates and sugars in seeds. Analysis of endogenous phytohormones in seeds at harvest revealed reduction in ABA concentration and an 33 increase in zeatin riboside and GA concentration in GA treated plants. W hile plants treated with ASA and IBA showed an opposite trend.