Isolation of Novel Conjugated Gibberellins from <i>Cucumis sativus</i> Seed

Hemphill, Delbert D.; Baker, L. R.; Sell, Harold M.

doi:10.1139/o73-221

Cited by 16 publications

(10 citation statements)

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“…Most endogenous GA is present as GA, and GA3 with traces of GA4 and GA7 (7). Conjugated derivatives of GA have also been identified from cucumber seed (8), but appear to play no regulatory role in sex expression. The primary hormones associated with female flower production are ethylene (1, 19,20) and auxin (5,6).…”

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confidence: 99%

Transport and Metabolism of ³H-Gibberellin A₁ in Dioecious Cucumber Seedlings

Rudich

Sell²,

Baker³

1976

Plant Physiol.

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The transport of 3H-GA1 through hypocotyl segments of cucumber (Cucumis sadivus L.) was found to be nonpolar. The transport of 3H-GA1 was increased by pretreatment with relatively high concentrations of either IAA or Ethephon (2-chloroethylphosphonic acid). Hypocotyl segments from plants of a gynoecious genotype transported more 3H-GA1 than those of an androecious. The metabolism of 3H-GA1 in hypocotyl segments was neither related to the sex genotype of the cucumber plant nor influenced by pretreatment with Ethephon. The primary metabolite of GA, was suggested to be GA8. Two other suspected metabolites were not identified. Differences in the endogenous GA of gynoecious and androecious plants could not be accounted for by transport differences.The sex expression of cucumber is influenced by the hormonal balance of auxin, ethylene, GA and ABA (1,5,6,18,20,21). Male flower production in cucumber is associated with endogenous GA levels (7,21,26). Exogenous application of GA3, GA4, GA7, and GA9 also increase the production of male flowers on both monoecious and gynoecious phenotypes (2, 26). Gynoecious phenotypes contain far less GA than monoecious (7,21), whereas the qualitative GA composition of both seeds and green plants is similar for all sex phenotypes. Most endogenous GA is present as GA, and GA3 with traces of GA4 and GA7 (7). Conjugated derivatives of GA have also been identified from cucumber seed (8), but appear to play no regulatory role in sex expression. The primary hormones associated with female flower production are ethylene (1,19,20) and auxin (5, 6). Treatment of cucumber plants with Ethephon actually decreases the endogenous GA activity (21).Accordingly, one possibility for the control of sex expression in cucumber is via ethylene biosynthesis and its effect on GA. Other possibilities (12) for hormonal control of sex expression might be a conversion from biologically active to inactive forms via conjugation or degradation, differences in biosynthesis, or differences in transport. We investigated the possibility that GA1 transport and/or metabolic differences as affected by ethylene might regulate the difference between male and female expression in cucumber. MATERIALS Hypobaric Ventilation. These experiments were conducted with explants under a reduced pressure of 0.2 atm to decrease internal ethylene concentration (1). Experiments were conducted over a 24-hr period with a gas mixture of 99.85% 02 and 0.15% C02. For ethylene treatments, the gas mixture was 99.85% 02, 3 ,u1/l C2H4, and 0.15% CO2. All experiments were conducted at a temperature of 25 C with continuous light (400 ft-c). All treatments were replicated three times in a completely randomized design.Radioactive 3H-GA1. Two sources of 3H-GA1 were used. The first was received from H. Kende (9) and had a specific radioactivity of 420 mCi/mmole. The second was received from L. Rappaport (14) with a specific radioactivity of 48 Ci/mmole. Experiments were conducted with 3H-GA1 concentrations of 1 iLM to 10 nM.Agar Block Preparation. ...

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confidence: 99%

Transport and Metabolism of ³H-Gibberellin A₁ in Dioecious Cucumber Seedlings

Rudich

Sell²,

Baker³

1976

Plant Physiol.

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“…The "base" shift occurs at a relatively low field because of the effect of the electronegative lOa-oxygen atom [6 2.49 for GAg (2)] and may be further deshielded by 1/8and/or 38-hydroxyls. Thus, the signal from the 5/3-H in GA4 (9) (3/8-OH) is observed at 8 3.22, in GAg! (1/3-OH) at 8 3.15, and in GAM [l/3,3/8-(OH)2] at 6 3.56.…”

Section: Bloactlvtty and Applicationsmentioning

confidence: 93%

“…In G. fujikuroi, the biosynthetic route to GA3 (1) proceeds via GA4 (9) and GA7 (10),122 whereas in higher plants, the sequence is GA20 (30) -* GA5 (32) -*• 1 (Figure 9)132 as shown with maize and a cell-free enzyme preparation from the seeds of Marah macrocarpus. 133 The latter also effects the parallel transformation of GA9 (2) and of 2,3-didehydro-GA9 (33) into GA7 (10).…”

Section: A Biosynthesis Of Gasmentioning

confidence: 99%

“…The observed activity of GAs without these features may be due to in situ metabolism which establishes these features. 98 Practical applications, however, have been confined to the fungal gibberellins, GA3 (1), GA4 (9), and GA7 (10).…”

Section: Bloactlvtty and Applicationsmentioning

confidence: 99%

“…(c) Control of russet, a scablike skin disorder in apples, (especially in "golden delicious") may be achieved by the application of the mixture of GA4 (9) and GA7 (10) obtained from G. fujikuroi (vide supra), although the GA7 in the mixture unfortunately tends to inhibit flowering in the following season and is not readily separated from the GA4.…”

Section: Bloactlvtty and Applicationsmentioning

confidence: 99%

See 2 more Smart Citations

The chemistry of gibberellins: an overview

Mander¹

1992

Chem. Rev.

123

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Untersuchungen zur Gibberellin‐ und Cytokininaktivität in verschiedenen Entwicklungsstadien der Karottenwurzel

Palussek

Neumann

1982

J Plant Nutrition & Soil

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In verschiedenen Entwicklungsstadien der Karottenpflanze wurden in der Vorratswurzel jeweils voneinander abweichende Cytokinin/Gibberellin‐Relationen festgestellt, wobei in der erntereifen Wurzel das Verhältnis der Aktivitäten dieser beiden Phytohormongruppen deutlich zugunsten der Cytokinine verschoben ist. In den Karottenwurzeln wurden zwei gibberellinaktive, eine gibberellinantagonistische und vier cytokininaktive Substanzen gefunden. Eine der gibberellinaktiven Substanzen trat auch in Konjugatform auf.

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Isolation of Novel Conjugated Gibberellins from Cucumis sativus Seed

Cited by 16 publications

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Transport and Metabolism of ³H-Gibberellin A₁ in Dioecious Cucumber Seedlings

Transport and Metabolism of ³H-Gibberellin A₁ in Dioecious Cucumber Seedlings

The chemistry of gibberellins: an overview

Untersuchungen zur Gibberellin‐ und Cytokininaktivität in verschiedenen Entwicklungsstadien der Karottenwurzel

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Isolation of Novel Conjugated Gibberellins from Cucumis sativus Seed

Cited by 16 publications

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Transport and Metabolism of 3H-Gibberellin A1 in Dioecious Cucumber Seedlings

Transport and Metabolism of 3H-Gibberellin A1 in Dioecious Cucumber Seedlings

The chemistry of gibberellins: an overview

Untersuchungen zur Gibberellin‐ und Cytokininaktivität in verschiedenen Entwicklungsstadien der Karottenwurzel

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Transport and Metabolism of ³H-Gibberellin A₁ in Dioecious Cucumber Seedlings

Transport and Metabolism of ³H-Gibberellin A₁ in Dioecious Cucumber Seedlings