A Comparison of Histological Responses of Bean Plants to Tryptophane and to Low Concentrations of Indoleacetic Acid

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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Chemical and Histological Responses of Bean Plants Grown at Different Levels of Nutrition to Indoleacetic Acid

Botanical Gazette ◽

10.1086/334944 ◽

1940 ◽

Vol 102 (1) ◽

pp. 206-216 ◽

Cited By ~ 10

Author(s):

Ora Smith ◽

L. B. Nash ◽

G. E. Davis

Keyword(s):

Indoleacetic Acid ◽

Bean Plants ◽

Different Levels

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TOLERANCE OF COMMON BEAN PLANTS TO ETHOXYSULFURON HERBICIDE AND THE MECHANISM INVOLVED IN THE PROCESS

Planta Daninha ◽

10.1590/s0100-83582016340300014 ◽

2016 ◽

Vol 34 (3) ◽

pp. 535-543 ◽

Cited By ~ 2

Author(s):

F.D.B. PAGNONCELLIJR. ◽

R.A. VIDAL ◽

M.M. TREZZI ◽

A. MACHADO ◽

M. GALLON ◽

...

Keyword(s):

Grain Yield ◽

Common Bean ◽

Field Experiments ◽

Plant Tolerance ◽

Herbicide Degradation ◽

Low Concentrations ◽

Bean Plants ◽

Herbicide Detoxification ◽

The Impact ◽

Common Bean Plants

ABSTRACT The objectives of this study were to determine the effect of herbicide ethoxysulfuron on the development of commom bean (Phaseolus vulgaris), to evaluate the impact of the herbicide on the crop grain yield and to determine the mechanism of tolerance of common bean to ethoxysulfuron. Field experiments were carried out with several doses of ethoxysulfuron to determine its effect on the grain yield of two varieties of common bean ("IPR Andorinha", "IPR Tangará"). The mechanism of plant tolerance was evaluated through several methods, including the analysis of the ALS enzyme sensitivity to herbicide and the use of P450 inhibitors (the insecticides malathion + chlorpyrifos) and the use of antidote (mefenpyr-diethyl). When the rate of ethoxysulfuron was 83.2 g ha-1, the grain yield loss reached 25% (IPR Tangará) and 35% (IPR Andorinha). The ALS enzyme activity was severely reduced even at low concentrations ethoxysulfuron (1 μM), indicating that the mechanism of tolerance is not the insensitivity of the herbicide target enzyme. The inhibitors of herbicide detoxification increased the sensitivity of the bean plants to ethoxysulfuron, and the antidote (stimulator of herbicide degradation) mitigated the herbicidal effect. These results strongly support the hypothesis that the mechanism of tolerance of common bean plants to ethoxysulfuron is enhanced herbicide detoxification.

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Decreased Lumbar Cerebrospinal Fluid Levels of Monoamine Metabolites in Vascular Dementia

International Psychogeriatrics ◽

10.1017/s1041610296002785 ◽

1996 ◽

Vol 8 (3) ◽

pp. 425-436 ◽

Cited By ~ 12

Author(s):

Anders Wallin ◽

Kaj Blennow ◽

Åke Edman ◽

Jan-Erik Månsson

Keyword(s):

Cerebrospinal Fluid ◽

Vascular Dementia ◽

Indoleacetic Acid ◽

Subcortical White Matter ◽

Control Group ◽

Monoamine Metabolites ◽

Low Concentrations ◽

Lumbar Cerebrospinal Fluid ◽

Fluid Levels ◽

Disease Specific

The levels of the monoamine metabolites 5-hydroxy-indoleacetic acid (5-HIAA), homovanillic acid (HVA), and 4-hydroxy-3-methoxyphenylglycol (HMPG) were determined in lumbar cerebrospinal fluid (CSF) of 56 patients with vascular dementia (VAD) and 57 healthy controls. Despite CSF sampling under standardized conditions, the variability in values was wide among both patients and controls. This suggests that yet unknown factors affect the lumbar CSF concentrations of monoamine metabolites. The VAD group showed significantly lower mean concentrations of 5-HIAA (p < .001) and HVA (p < .001) than the control group. These low concentrations appear to be no disease-specific phenomenon, but may be attributable to subcortical white-matter changes or a decreased production of monoamines, which are dependent on oxygen for their synthesis.

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Stimulating Effect of Beta(3)Indoleacetic Acid on Synthesis of Solid Matter by Bean Plants

Botanical Gazette ◽

10.1086/334731 ◽

1938 ◽

Vol 99 (3) ◽

pp. 569-583 ◽

Cited By ~ 8

Author(s):

John W. Mitchell ◽

Charles L. Hamner

Keyword(s):

Indoleacetic Acid ◽

Solid Matter ◽

Bean Plants

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