Measuring and interpreting respiratory critical oxygen pressures in roots.

Background and Aims: Respiratory critical oxygen pressures (COPR) determined from O2-depletion rates in media bathing intact or excised roots are unreliable indicators of respiratory O2-dependency in O2-free media and wetlands. A mathematical model was used to help illustrate this, and more relevant polarographic methods for determining COPR in roots of intact plants are discussed. [ABSTRACT FROM PUBLISHER]