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It has been suggested that the inhibition of catalase (CAT) (EC 1.11.1.6) by salicylic acid (SA) plays a role in mediating stress responses. In this work, it is proposed that CAT-1 and CAT-2 isozymes of maize (Zea mays L.) might differ in the nature of SA inhibition, as it was shown for 0 and 9 dpi (days postimbibition) scutellum preparations, containing mainly CAT-1 and CAT-2 isozymes, respectively. In the case of 9 dpi extract, only a weak, competitive inhibition of CAT activity was observed upon treatment with SA or several other phenolic compounds. On the other hand, CAT activity of the 0 dpi extract was inhibited to a significantly greater extent and in a non-competitive manner by SA and its analogues, except for p-hydroxybenzoic acid (pHBA), which showed the same kinetics of inhibition as for 9 dpi samples. All of the phenolic compounds but pHBA, were found to significantly increase chilling tolerance when …