Physiological Response of Different Pepper Varieties to Drought Stress

In order to study the physiological and biochemical responses of different pepper varieties to the drought stress, the seedlings of three different varieties of pepper, including Lamei 520, Jinjiao Weifeng and Jinjiao 1.0, were used as the experimental materials. By using the controlled watering of potted plants to simulate the drought, the effects of drought stress (moderate drought and soil relative water content of 40%-45%) treated for 7 days on the activities of superoxide dismutase, catalase, peroxidase, soluble protein content, proline content and malondialdehyde content of three pepper varieties were studied. The results showed that the superoxide dismutase (SOD) activity, catalase (CAT) activity, peroxidase (POD) activity, soluble protein (SP) content and proline (Pro) content of Lamei 520 were the highest, followed by those of Jinjiao Weifeng, and Jinjiao 1.0 was the lowest. However, the malondialdehyde (MDA) content of Lamei 520 was the lowest, followed by Jinjiao Weifeng, and Jinjiao 1.0 was the highest. In conclusion, the drought resistance of the three varieties of pepper was as follows: Lamei 520>Jinjiao Weifeng>Jinjiao 1.0. The pepper with strong resistance had higher antioxidant enzyme activity, higher osmotic substance accumulation and lower malondialdehyde (MDA) content, while the pepper with weak resistance had the opposite.