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Abscission: the role of aging
F B Abeles1, R E Holm, H E Gahagan
1Department of the Army, Fort Detrick, Frederick, Maryland 21701.
Plant Physiology
|October 1, 1967
Summary
Plant abscission and senescence are independent processes that occur simultaneously. Research shows ethylene promotes abscission without increasing senescence, indicating separate pathways in Phaseolus vulgaris L.
Area of Science:
- Plant Biology
- Molecular Biology
- Biochemistry
Background:
- The abscission zone in Phaseolus vulgaris L. (Red Kidney bean) explants initiates senescence, mobilization, and abscission upon excision.
- Simultaneity of these processes raises questions about their causal relationship.
Purpose of the Study:
- To investigate whether senescence and abscission are causally linked or independent processes in Phaseolus vulgaris L. abscission zone explants.
Main Methods:
- Excision of abscission zone explants from Phaseolus vulgaris L. c.v. Red Kidney.
- Observation of senescence, metabolite degradation, and abscission.
- Treatment with ethylene, indoleacetic acid, cytokinins, and coumarin.
Main Results:
- Excision triggers aging and metabolite degradation in explants.
- Explants become more sensitive to ethylene, which promotes cell separation and abscission.
- Indoleacetic acid, cytokinins, and coumarin retard aging, inhibiting degradation and abscission.
- Ethylene induced abscission independently of degradation, supporting distinct processes.
Conclusions:
- Senescence and abscission are independent processes occurring concurrently in Phaseolus vulgaris L. abscission zones.
- Ethylene's role in promoting abscission without affecting senescence highlights their distinct mechanisms.
- Hormonal regulation by indoleacetic acid, cytokinins, and coumarin influences both aging and abscission.
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