Stress Sensitivity of Correlation between POD and PPO Activities in Plants

In the leaf extracts of two plant species (Quercus robur L. and Phaseolus vulgaris L.),peroxidase (POD) and polyphenol oxidase (PPO) activities have been measured by the methods ofShannon et al (1966) and Flurkey and Jen (1978). The oxidative activities regarded as semi-empiricalbiochemical variables have distributions in the plant foliage and between them a linear correlation hasbeen observed. In this work the resultant oxidative activities of POD and PPO isoenzymes of plantfoliages, the measuring uncertainties of their values and their correlation are interpreted. For theeffects of cold shock and lack of illumination, significant alterations in the correlation have beenrevealed that are also reflected by the parameters of the regression. The correlation of POD and PPOhas been established to be stress sensitive by the application of covariance analysis (ANCOVA).