Investigating Water Productivity, Characteristics and Elements Concentration of Mentha piperita L under Cadmium Stress in the presence of Selenium

Cadmium is one of the most important toxic heavy elements for plants. Selenium is a necessary and useful element in increasing tolerance to environmental stresses in plants. In this research which was performed in a research greenhouse in Torbat-e Jam region, Iran during 2021, The effect of cadmium in 3 levels (0, 75 and 150 mgrperlit CdCl2, and selenium factor in 2 levels (0 and 5 mgrperlit Na2SeO4) and was done in three replications. The results showed that with the increase of cadmium stress levels from 0 to 75 and 150, fresh and dry weight, water productivity, essential oil percentage and plant height decreased. Also, foliar spraying of selenium increased above fresh and dry weight, water productivity, essential oil percentage and plant height respectively 67/33, 67/98, 68/11, 61/16 and 40/68 percent compared to the absence of selenium. The results of the interaction effects of cadmium and selenium showed that foliar spraying of selenium with concentrations of 5 milligrams per liter in cadmium stress levels increased fresh and dry weight, water productivity and plant height compared to not consuming of selenium. Also, the results showed that foliar spraying of selenium at cadmium stress levels caused a change in the concentration of iron, zinc, sodium, potassium and cadmium in the leaves of peppermint compared to the absence of foliar spraying of selenium. The results indicated that with the increase of cadmium stress levels from 0 to 75 and 150, selenium decreases the concentration of cadmium in peppermint leaves respectively 23/97, 14/84 and 14/23 percent. The results indicated that water productivity decreased with the increase of cadmium stress. Also, selenium foliar application reduced the effects of cadmium stress.