Morphophysiological and phytochemical responses to cadmium and lead stress in coriander (Coriandrum sativum L.)

In some production areas of the world contaminated soil or water with heavy metals are used for edible crop productions. Therefore, the objective of this research was to investigate the effects of cadmium levels (Cd, 0, 5, 10, and 20 mg kg(-1) of soil) and lead levels (Pb, 0, 100, 200, and 400 mg kg(-1) of soil) on the morphological, physiological, and phytochemical traits of coriander were investigated under greenhouse conditions. Also, using coriander plants for either fresh consumption or used for essential oil extraction were evaluated under heavy metal soil stress conditions. The obtained data showed that by increasing the Cd and Pb levels, plants flower earlier, and the stem diameter increases, accordingly. Leaf relative water content (% RWC), plant dry weight, leaf area, and leaf vitamin C concentration of treated plants were reduced in comparison with control. Compared with control, Fv/Fm indices were significantly reduced under Cd and Pb treatments. Essential oil content (0.18-0.30 %), total phenolics content (250-280 mu g kg(-1)), and total flavonoids (142-167 oil mu g kg(-1)) were higher in Cd and Pb treated plants than in control. In addition, the Cd and Pb had adverse effects on both morphological and physiological traits, whereas had positive effects on leaf phytochemical attributes. Since coriander behaves as a heavy metals (HMs) accumulator and has a high level of important medicinal phyto-chemicals, its cultivation in HMs contaminated soils can be recommended only for medicinal purposes.