Improved drought tolerance in soybean by protein elicitor AMEP412 induced ROS accumulation and scavenging

Abstract

AbstractDrought stress is a major limiting factor for soybean production. In this study, protein elicitor AMEP412 was applied on soybean seedlings to promote drought tolerance, and its correlation with alterations in the reactive oxygen species (ROS) in leaves was studied. The plants of soybean cv. Suinong 26 were sprayed with AMEP412 at the V1 stage and then treated with drought stress and rehydration. The alterations in phenotypes, physiological indices, ROS levels and antioxidant system as well as lipid peroxidation were monitored. The results showed that spraying AMEP412 significantly promoted the drought tolerance of soybean seedlings. Soybean seedlings pre-treated with AMEP412 performed better in phenotypes and physiological indexes, like leaf relative water content (RWC), leaf relative conductivity (RC) and osmolytes (free proline, soluble sugar and protein). In addition, the in situ and quantification detection of ROS revealed that AMEP412 pretreatment led to higher accumulation of ROS at the early stage and faster scavenging of ROS at the late stage. Moreover, AMEP412 pretreatment increased the activity of superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione peroxidase (GPX), and the levels of ascorbate (AsA) and glutathione (GSH), but decreased the level of malondialdehyde (MDA) as compared with only drought treatment. Overall, the results indicated that AMEP412 was effective in alleviating the adverse effects of drought stress, which was partially attributable to the ROS accumulation and scavenging triggered by AMEP412.

Keywords

• Soybean
• drought stress
• protein elicitor
• reactive oxygen species
• mechanism