Depletion of Oxygen in Roots of Wheat and Maize by Respiration Following Encasement in Olive Oil

Abstract The extent to which isolated root systems of 14-d-old seedlings of wheat ( Triticum aestivum ) and maize ( Zea mays ) were depleted of oxygen by respiration was measured after immersing them in outgassed olive oil to exclude oxygen entry from the air. At intervals over 45 min, gas from the roots was removed under partial vacuum and oxygen partial pressures measured by gas chromatography. Contrary to earlier findings (Erdmann and Wiedenroth, 1988), roots were able to utilize almost all of their oxygen within 20 min at 25°C, including that dissolved in the thin water covering interposed between roots and oil. The rate of aerobic respiration could be estimated readily from the time course of oxygen depletion.