Impact of Drought, Salinity, and Heavy Metal Stress on Growth, Nutrient Uptake, and Physiological Traits of Vetiver Grass (Chrysopogon zizanioides L.)

Abstract

Drought and salinity are the most common abiotic stresses in arid and semi-arid regions. Vetiver grass is one of the best plants for planting in heavy metal contaminated areas. Therefore, the impact of drought, salinity, and heavy metal stress on growth, nutrient uptake, and physiological traits of vetiver has been investigated in this research. The greenhouse experiment was conducted as a completely randomized design in a factorial arrangement with three replications. Drought stress was performed at two levels of control (field capacity) and water stress conditions (25% field capacity) (defined as FC and 25%FC, respectively). The salinity treatment was applied to the relevant pots in two levels (0 and 100 mM sodium chloride (NaCl) defined as S0 and S1, respectively). The cadmium stress was exerted with 0 and 12 mM cadmium nitrate concentrations (defined as Cd0 and Cd1, respectively). The results indicated the highest values of root length and root weight (as 52.14 and 31.22, respectively) were observed in the 25% FC S1 Cd0 treatment. The minimum amount of root length and root weight reported as 15.32 and 10.52 that seen in FC S0 Cd0 treatment. The highest values of potassium (K), calcium (Ca), iron (Fe), magnesium (Mg), zinc (Zn), and phosphorus (P) were seen in the FC S0 Cd0 treatment. Moreover, the lowest value of sodium (Na) concentrations was 4.92 (g kg−1), observed in FC S0 Cd0. The maximum content of proline and the lowest total nitrogen content (TNC) values in Chrysopogon zizanioides tissue indicated as 0.41 μmol gFW−1 and 0.97% which seen in 25% FC S1 Cd1 treatment.