Chilling Stress to Soybeans during Imhibition
W J Bramlage1, A C Leopold, D J Parrish
1Department of Agronomy, University of Nebraska, Lincoln, Nebraska 68583.
Plant Physiology
|April 1, 1978
Summary
Soybean embryos leak solutes during imbibition, especially at low temperatures. Pre-humidifying soybean embryos reduces leakage and chilling injury by aiding membrane reorganization.
Area of Science:
- Plant physiology
- Biochemistry
- Seed science
Background:
- Soybean embryos exhibit significant solute leakage upon initial imbibition.
- Temperature significantly influences the rate of solute leakage and subsequent injury.
Purpose of the Study:
- To investigate the relationship between imbibition temperature, solute leakage, and chilling injury in soybean embryos.
- To determine if pre-imbibition humidification can mitigate low-temperature-induced injury.
Main Methods:
- Excising soybean embryos and subjecting them to controlled imbibition temperatures (10°C or lower).
- Measuring solute leakage and assessing embryo germination and axis elongation.
- Comparing embryos with and without pre-imbibition humidification (35-50% moisture).
Main Results:
- A temperature discontinuity between 10-15°C affects solute leakage patterns.
- Imbibition at or below 12-14°C for short durations (e.g., 5 minutes at 2°C) reduces germination and elongation.
- Pre-humidification significantly reduced leakage and conferred resistance to imbibitional chilling injury.
Conclusions:
- Low temperatures interfere with membrane reorganization during imbibition, leading to injury.
- Solute leakage is indicative of membrane reorganization processes.
- Pre-humidification may facilitate partial membrane reorganization, enhancing cold tolerance.
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