The Effect of Iodine on Rocket (Eruca sativa L.) Plant Under Salt Stress

The main objective of this study was to investigate how iodine biofortification (potassium iodate (KIO3)) applied to rocket affects the physiological and biochemical responses of the plant under salt stress. Rocket (Eruca sativa L.) seeds were used as material and the applications were started when the seeds germinated and the plants had 2-3 leaves. 50 (T1) and 100 (T2) µM KIO3 applications were applied to the leaves of the plants by spraying and also by irrigation to the soil. Salt stress was applied by applying water prepared with 100 mM NaCl to the plant as irrigation from the soil. The effects of the applications on some plant morphological and physiological properties were investigated. In the study, salinity significantly reduced plant growth and development in rocket. Iodine application alleviated this damage and supported growth in rocket against salt stress. The plant height, stem diameter, leaf number and leaf area decreased by 29%, 27%, 22% and 56%, respectively, under salt stress, while iodine applications reduced this decrease. Electrical conductivity (EC) increased with salinity, while leaf water relative content (LRWC) decreased in rocket. This effect of salt was low in iodine application. Plant fresh weight, root fresh weight, plant dry weight and root dry weight decreased by 55%, 13%, 20% and 10% in the control group with salinity, and iodine application mitigated this decrease. The chlorophyll content, root fresh and dry weight of plants, especially those under salt stress, increased with iodine application. Hydrogen peroxide (H2O2), malondialdehyde (MDA), proline, sucrose and antioxidant enzyme activities, which increased with salinity, also increased with iodine application. Iodine supports plant development and is also effective in salt stress tolerance of rocket plants.