Effects of Indoleacetic Acid and Gibberellic Acid on Normal and Dwarf Tomatoes

1958 ◽  
Vol 119 (3) ◽  
pp. 197-200 ◽  
Author(s):  
T. H. Plummer ◽  
M. L. Tomes
Keyword(s):  
Gibberellic Acid ◽  
Indoleacetic Acid

Hill-Activity and P700 Concentration of Chloroplasts Isolated from Radish Seedlings Treated with -Indoleacetic Acid, Kinetin or Gibberellic Acid

1977 ◽  
Vol 32 (9-10) ◽  
pp. 798-802 ◽  
Author(s):  
Claus Buschmann ◽  
Hartmut K. Lichtenthaler
Keyword(s):  
Steady State ◽  
Gibberellic Acid ◽  
Photosynthetic Activity ◽  
Indoleacetic Acid ◽  
Photosynthetic Apparatus ◽  
Promotion Effect ◽  
Hill Activity ◽  
The Hill ◽  
Radish Seedlings ◽  
Very High

Abstract The Hill-activity (reduction of DCPIP or methylviologen) and the concentration of P700 were studied in chloroplasts isolated from cotyledons of radish seedlings (R aphanus sativu s L. Saxa Treib), which had been grown with the addition of β-indoleacetic acid (IAA), kinetin, or gibberellic acid.1) The photosynthetic activity of young chloroplasts from 3 day old Raphanus seedlings is very high (c. 180 μmol O2/mol chlorophyll × h) and decreases continuously thereafter with increasing age. The steady state Hill-activity is readied after 8 to 10 days (values of 55 to 50 μmol 02/mg chlorophyll × h).2) Chloroplasts from plants treated with IAA or kinetin not only exhibit higher plastoquinone levels 1,2, but also a higher P700-content and a higher Hill-activity. The promotion effect is more pronounced with kinetin (+ 36 to 40%) than with IAA (+ 12 to 17%).3) Gibberellic acid has a different effect on composition and activity of chloroplasts. In younger seedlings the Hill-activity appears to be somewhat stimulated, without promotion effect on plasto­ quinone 2 or P700 concentration. After 10 days GA3-treated plants show signs of chlorosis combined with a strong decrease in photosynthetic activity.4) The data clearly demonstrate that the composition and activity of the photosynthetic ap­ paratus are under phytohormone control. IAA and even better kinetin promote the light induced formation of pigment systems and electrontransport chains. GA3 seems to block the rebuilding of the photosynthetic apparatus under steady state conditions.

Increase of indoleacetic acid oxidase isoenzymes by gibberellic acid in tobacco callus cultures

1971 ◽  
Vol 49 (5) ◽  
pp. 687-693 ◽  
Author(s):  
T. T. Lee
Keyword(s):  
Gibberellic Acid ◽  
Indoleacetic Acid ◽  
Polyacrylamide Gel Electrophoresis ◽  
Callus Cultures ◽  
Tobacco Callus ◽  
Acid Oxidase ◽  
Iaa Oxidase ◽  
Characteristic Type ◽  
Indoleacetic Acid Oxidase ◽  
Callus Tissues

Indoleacetic acid (IAA) oxidase in tobacco callus tissues (Nicotiana tabacum L., cultivar White Gold) grown on a medium supplemented with gibberellic acid (GA3), IAA, and kinetin was resolved into seven isoenzymes by polyacrylamide gel electrophoresis. Gibberellic acid promoted the development of three fast-migrating IAA oxidase isoenzymes which were 7- to 10-fold more active than those of the control. Gibberellic acid was effective at 2 × 10−9 M and its activity increased with increasing concentration up to 2 × 10−7 M. Actinomycin D and cycloheximide inhibited the development of these isoenzymes, suggesting a requirement for both RNA and protein synthesis. The GA3-promoted IAA oxidase isoenzymes increased with time and were positively associated with the GA3-induced characteristic type of growth.The expression of the GA3 effect on IAA oxidase isoenzymes and growth was dependent on IAA and kinetin. In the presence of appropriate concentrations of kinetin, the combined effect of GA3 and IAA was more than additive. A possible interpretation of the GA3–IAA interaction is discussed.

Bud Sprouting and Growth of Purple Nutsedge Altered by Benzyladenine

Weed Science ◽  
1973 ◽  
Vol 21 (1) ◽  
pp. 19-23 ◽  
Author(s):  
Chris K. H. Teo ◽  
Leo E. Bendixen ◽  
Roy K. Nishimoto
Keyword(s):  
Abscisic Acid ◽  
Gibberellic Acid ◽  
Indoleacetic Acid ◽  
Growth Habit ◽  
Cyperus Rotundus ◽  
Purple Nutsedge ◽  
Bud Sprouting ◽  
Continuous Presence ◽  
Delayed Flowering

Varying concentrations of benzyladenine (BA), indoleacetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA), and 2-chloroethylphosphonic acid (ethephon) were used to induce sprouting of dormant purple nutsedge (Cyperus rotundusL.) tubers. BA at 50 to 300 ppm stimulated sprouting. The continuous presence of BA during the sprouting period was necessary to give significant sprout stimulation. Neither IAA at 1, 10, or 100 ppm; GA at 10, 100, or 1000 ppm; nor ethephon at 10, 100, or 1000 ppm had stimulatory effects on sprouting. ABA counteracted the stimulatory effects of BA when tubers were treated with ABA following BA treatment. Sprouting was markedly greater at 33 C day, 25 C night than at 24 C day, 17 C night. Growth of plants originating from tubers pretreated with 100 ppm BA did not differ significantly from the controls. Sustained BA applications at 100 and 200 ppm produced numerous plants with tuft-type growth habit, delayed flowering, and reduced the number of inflorescences. Numerous short, diageotropic rhizomes were produced.

Growth of the gynophore of the peanut Arachis hypogaea. 2. Regulation of growth

1990 ◽  
Vol 68 (5) ◽  
pp. 965-978 ◽  
Author(s):  
Deborah D. Shushu ◽  
Elizabeth G. Cutter
Keyword(s):  
Gibberellic Acid ◽  
Arachis Hypogaea ◽  
Indoleacetic Acid ◽  
Soil Surface ◽  
Triiodobenzoic Acid ◽  
Arachis Hypogaea L ◽  
Low Concentrations ◽  
Intercalary Meristem ◽  
Growth Promoting ◽  
Regulation Of Growth

It was previously shown that removal of the ovary, which occupies the distal millimetre, caused cessation of growth of the gynophore and its intercalary meristem, suggesting that the ovary was a source of growth-promoting substances. Control of growth was studied in the gynophore of the peanut Arachis hypogaea L., cv. Bukene No. 2. Low concentrations of indoleacetic acid promoted growth of decapitated gynophores, whereas high levels inhibited elongation. Gibberellic acid promoted growth of the decapitated gynophores, whereas kinetin inhibited growth at all concentrations used. A combination of indoleacetic acid and gibberellic acid promoted extension growth of the decapitated gynophores above that of the intact gynophores; this was characterized, however, by a different pattern of cell division and cell elongation from that observed in the intact gynophores. Indoleacetic acid affected the "youngest" tissues, whereas gibberellic acid affected the whole length of the growing zone. High levels of indoleacetic acid caused diageotropism of the gynophores. Application of [14C] indoleacetic acid to vertical gynophores after the ovary was excised indicated that indoleacetic acid became redistributed to one side, resulting in horizontal bending. Thus an increased amount of auxin from the enlarging ovary may be involved in placing the ovary parallel to the soil surface when it reaches a suitable depth in the soil, during normal geocarpic development. Triiodobenzoic acid reduced growth when applied in lanolin as a ring between the ovary and the meristem but not when applied proximal to the meristem, suggesting that triiodobenzoic acid prevented the transport of auxin from the ovary to the meristem.

Morphogenesis of the stamenless-2 mutant in tomato. II. Modifications of sex organs in the mutant and normal flowers by plant hormones

1973 ◽  
Vol 51 (12) ◽  
pp. 2473-2479 ◽  
Author(s):  
Vipen K. Sawhney ◽  
Richard I. Greyson
Keyword(s):  
Gibberellic Acid ◽  
Plant Hormones ◽  
Indoleacetic Acid ◽  
Single Gene ◽  
Apparent Effect ◽  
Viable Pollen ◽  
Stamen Development ◽  
Auxin Content

Application of gibberellic acid (GA3) to young plants of a single gene recessive stamenless-2 (sl2/sl2) mutant of tomato produced 'phenocopies' of the normal plants. Unlike the untreated sl2/sl2 mutant, flowers of GA3-treated plants bore no external ovules, possessed more yellow-pubescent stamens and fewer carpelloid stamens per flower, and produced laterally fused stamens. Stamen length at maturity was similar to normal flowers. In addition, viable pollen resembling the normal was produced in GA3-treated sl2/sl2 flowers. It was also found that GA3 was more effective than GA4+7 in inducing stamen development. Normal plants treated with GA3 produced multicarpellary and multilocular ovaries. Indoleacetic acid (IAA) induced the carpellization of stamens in sl2/sl2 flowers but had no apparent effect on the flowers of normal plants. It is proposed that added gibberellins promote maleness in systems where there is an inhibition or abnormality of stamen development, whereas they stimulate femaleness (possibly through an increase in auxin content) in systems with normal stamen development.

scholarly journals In Vitro Propagation of Viburnum opulus ‘Nanum’

1985 ◽  
Vol 3 (2) ◽  
pp. 41-45
Author(s):  
Virginia Hildebrandt ◽  
Patricia M. Harney
Keyword(s):  
Gibberellic Acid ◽  
In Vitro Propagation ◽  
Indoleacetic Acid ◽  
Basal Medium ◽  
Shoot Proliferation ◽  
Shoot Tips ◽  
Viburnum Opulus ◽  
Adenine Sulfate ◽  
Growing Shoot

Explants of actively growing shoot tips from greenhouse-grown plants of Viburnum opulus ‘Nanum’ initiated new shoots on a modified Murashige and Skoog (MS) revised medium plus 0.1 mg/L indoleacetic acid (IAA). These shoots were transferred for proliferation to the same medium, but with 1 mg/L 6-benzylamino purine (BA) replacing IAA and the addition of 2.5 mg/L 2-iso-pentenyladenine (2iP). Both adenine sulfate AdS) and NaH2PO4.H2O inhibited shoot proliferation, while gibberellic acid (GA3) and glycine had no effect. The shoots could be rooted either in the basal medium without cytokinin or in vermiculite under mist.

Relationship between S-ethyl dipropylthiocarbamate injury and peroxidase activity in corn seedlings

1975 ◽  
Vol 53 (2) ◽  
pp. 225-230 ◽  
Author(s):  
B. M. R. Harvey ◽  
F. Y. Chang ◽  
R. A. Fletcher
Keyword(s):  
Gibberellic Acid ◽  
Mechanism Of Action ◽  
Peroxidase Activity ◽  
Indoleacetic Acid ◽  
Time Study ◽  
Lignin Deposition

The herbicide EPTC (S-ethyl dipropylthiocarbamate) stimulated peroxidase activity in corn seedlings and enhanced lignin deposition during the first few days after treatment. A time study showed that the increase in peroxidase was concomitant with the inhibition in growth. The effects of EPTC on growth and peroxidase activity were annulled by the herbicide antidote (N,N-diallyl-2,2dichloroacetamide) but not by indoleacetic acid or gibberellic acid. The mechanism of action of EPTC and the antidote are discussed.

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