Regulation of Growth and Invertase Activity by Kinetin and Gibberellic Acid in Developing Avena Internodes

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.

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Gibberellin-enhanced sugar accumulation in growing subhooks of etiolated Pisum sativum seedlings. Effects of gibberellic acid, indoleacetic acid and cycloheximide on invertase activity, sugar accumulation and growth

Physiologia Plantarum ◽

10.1034/j.1399-3054.1993.880214.x ◽

1993 ◽

Vol 88 (2) ◽

pp. 301-306 ◽

Cited By ~ 1

Author(s):

Kensuke Miyamoto ◽

Junichi Ueda ◽

Seiichiro Kamisaka

Keyword(s):

Pisum Sativum ◽

Gibberellic Acid ◽

Indoleacetic Acid ◽

Invertase Activity ◽

Sugar Accumulation

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REGULATION OF GROWTH AND CELLULAR DIFFERENTIATION IN DEVELOPING AVENA INTERNODES BY GIBBERELLIC ACID AND INDOLE-3-ACETIC ACID

American Journal of Botany ◽

10.1002/j.1537-2197.1969.tb09742.x ◽

1969 ◽

Vol 56 (8) ◽

pp. 918-927 ◽

Cited By ~ 15

Author(s):

Peter B. Kaufman ◽

Louise B. Petering ◽

Paul A. Adams

Keyword(s):

Acetic Acid ◽

Gibberellic Acid ◽

Cellular Differentiation ◽

Regulation Of Growth ◽

Indole 3 Acetic Acid

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Regulation of invertase activity and growth in rice (Oryza) coleoptile sections by gibberellic acid and sucrose

Canadian Journal of Botany ◽

10.1139/b72-144 ◽

1972 ◽

Vol 50 (6) ◽

pp. 1185-1190 ◽

Cited By ~ 4

Author(s):

Sarvjit L. Soni ◽

Peter B. Kaufman

Keyword(s):

Growth Rate ◽

Enzyme Activity ◽

Gibberellic Acid ◽

State Level ◽

Close Correlation ◽

Invertase Activity ◽

Maximal Growth ◽

Steady State Level ◽

Maximal Growth Rate ◽

Rice Coleoptile

Changes in invertase activity and growth were examined in excised rice coleoptile sections which were treated with water, gibberellic acid (GA3), sucrose, and GA3 + sucrose. Invertase activity with all treatments rises in parallel during the first 6 h. Between 6 and 12 h, the GA3 and GA3 + sucrose treatment causes the invertase activity to increase at a faster rate than the respective water and sucrose controls. For all treatments, the peak invertase activity occurs at 12 h; it then declines rapidly between 12 and 24 h. After this, the enzyme activity becomes stable by 36 h for sucrose and GA3 + sucrose treatments. In contrast, in water and GA3 treatments, the enzyme activity continues to decrease up to 48 h, then attains a steady state level. With water, GA3, sucrose, and GA3 + sucrose, there is a close correlation between the time of maximal invertase activity and the time of maximal growth rate (12 h), and the kinetics for promotion of both processes are essentially the same. This study indicates that both GA3 and sucrose may be involved in regulating levels of invertase and that invertase activity is closely associated with growth in rice coleoptile sections.

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