Effects of drought period and its recovery on growth and antioxidant enzymes activity of three Atriplex species

The present study was conducted to evaluate drought stress and subsequent recovery on growth and biochemical changes of three Atriplex species. The study was performed as factorial based on completely randomize design with six replicates. The treatments included three Atriplex species (A. lentiformis, A. leucocalada and A. canescence) and four irrigation regimes (100 as control, 75% FC as light stress, 50% FC as severe drought, and no irrigation). The results showed that light and severe drought caused a significant reduction in growth of all three Atriplex species, and no irrigation treatment caused the loss of A. leucocalada and A. canescence. The recovery could offset the loss partly in all three species, especially A. lentiformis, so that there were no significant differences between control and 75% FC treatments. Tissue moisture percentage showed no significant difference in control, 75, and 50% FC. In A. lentiformis, no irrigation treatment caused a significant reduction in moisture percentage; however, recovery offset a considerable part of this loss. Water deficit treatments (75 and 50% FC) increased the activity of catalase, peroxidase and superoxide dismutase. The highest activity of all four enzymes was obtained in A. lentiformis. Generally, drought stress, depending on stress levels, reduced the growth and increased the antioxidant enzymes in all three-study species, and recovery, depending on species and stress levels, could offset a part of this loss. A. lentiformis showed the highest drought resistance and higher recovery ability, which might be due to the higher activity of antioxidant enzymes.