Abstract:

To study the effects of drought on antioxidant enzymes and osmotic substances of different types of winter wheat roots, we used water-fertilizer wheat cultivar ‘Jimai 22’ (J22) and drought-tolerant wheat cultivar ‘Qingmai 6’ (Q6) as materials to simulate the field environment through PVC soil pillars. Two treatments were normal condition and drought treatment during the full growth period, and then we observed the changes of root morphology, dry matter weight, SOD, MDA and POD enzyme activity of different types of wheat. With the development of wheat, the number of wheat populations, POD activity and soluble sugar content in root system decreased gradually; the SOD activity and proline content in the root system increased first and then decreased; and MDA content gradually increased. The two different types of winter wheat showed different trends under different conditions. The SOD, POD activity and soluble sugar content in the root system of J22 were significantly greater than those of Q6 under water condition. However, in the absence of water, compared with those of J22, the population number, SOD, POD enzyme activity, soluble sugar, and proline content of Q6 increased significantly. Under drought stress, Q6 shows strong antioxidant ability of regulating cell osmotic potential in the root system, thus maintaining water balance and enhancing adaptability to the stress.

Key words: wheat, root, superoxide dismutase, peroxidase, malondialdehyde, soluble sugar content