Effect of arbuscular mycorrhizal fungi on the metabolic products and activity of antioxidant system in wheat plants subjected to short-term water stress, followed by recovery at different growth stages

Abstract

The effect of arbuscular mycorrhizal (AM) fungi on the metabolic changes and the activity of antioxidant system on wheat (Triticum aestivum L cv. Sakha 93) plants were investigated in pot culture under well-watered (ww) and water stress (ws) conditions. The water stress treatment was applied by increasing the irrigation interval from one week to two weeks at three growth stages (tillering, heading and grain-filling). After each stress period, the plants were watered and grown to maturity without subsequent water stress (recovery periods). Results showed that, at water stress and rewatering, the mycorrhizal inoculation significantly increased the contents of some metabolites (proline; free amino acids; total soluble and crude proteins; total carbohydrate; total soluble and insoluble sugars) in wheat plants and enhanced the activities of some antioxidant enzymes such as peroxidase (POX) and catalase (CAT) as compared with stressed control, especially at heading stage of plant growth. The overall results, suggest that mycorrhizal colonization could improve the osmotic adjustment response of wheat plants, enhance its defence system, and alleviate oxidative damage of cell viability. The cumulative effects increased the plant tolerance to drought.