Influence of Mycorrhizal Fungi Inoculation on Growth Characteristics, Membrane Stability, Relative Water Content and Elements uptake of Coriander under Cadmium Stress

Heavy metals are one of the pollutants in the ecosystem. They are of great importance due to their specific physiological effects on living organisms, even at low concentrations. Cadmium is one of the most important heavy metals due to its high mobility in the soil, and high solubility in water and soil. For this purpose, a pot experiment was carried out in a completely randomized design with factorial arrangement and two factors and three replications at the Faculty of Agriculture, Ferdowsi University of Mashhad, to evaluate the growth characteristics, membrane stability, relative water content and uptake of some nutrients in coriander (Coriandrum sativum L.) under heavy metal stress and mycorrhizal inoculation. The first factor was cadmium nitrate in 4 levels of 0, 40, 20, 80 mg/kg soil, and the second factor was mycorrhiza in 3 levels (without fungi inoculant, Funnetiformis mosseae, and Rhizophagus intraradicese). The results showed that with increasing stress levels, the membrane stability index, root colonization percentage, and the concentration of nitrogen, phosphorus, potassium, calcium, iron, and zinc in coriander were significantly reduced. While increasing cadmium concentration in soil, increased significantly cadmium concentration and relative water content of leaf (p ≤ 0.01). However, the mycorrhiza inoculation reduced the harmful effects of cadmium in the plant. The highest concentrations of nitrogen (3.08%), phosphorus (0.126%), calcium (2.92%), magnesium (0.85%), and zinc (121 mg/kg) were observed in mycorrhizal fungi application. Funnetiformis mosseae was more effective than Rhizophagus intraradices with a 42% decrease in cadmium concentration of leaf at the highest level of soil cadmium contamination (80 mg/kg cadmium nitrate). Inoculation with mycorrhizal fungi (especially Funnetiformis mosseae) increased plant tolerance against cadmium stress. So, plants inoculated with mycorrhizal fungi had higher growth and yield than non-inoculated plants, and their application in these conditions is recommended.