Water deficit is the most important abiotic stress that seriously affects plant production. Various strategies are proposed to reduce cell damage caused by the stresses to improve dehydration tolerance. Therefore, this study was carried out to investigate the effect of foliar application of polyamines (Putrescine, Spermine, and Spermidine; Put, Spm, and Spd, respectively) on the antioxidant enzyme contents in chamomile plants under water deficit (100, 80, and 60% of field capacity, I100, I80, and I60, respectively). The results showed that water deficit increased the content of antioxidant enzymes. The highest leaf catalase and ascorbate peroxidase content were observed at I60Spd. However, the highest leaf peroxidase and superoxide dismutase content were observed at I60Spm. The application of polyamines had a positive effect on increasing antioxidant enzyme content in stressful conditions. According to the results, the foliar application of Spd had the most stimulating effect on increasing antioxidant enzyme content. It can be concluded that foliar application of polyamines led to an increase in the content of antioxidant enzymes and greater plant tolerance to water deficit.

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