Effects of two mycorrhiza species (Glomus mosseae and G. interaradices) on some morphological and physiological characteristics of Pelargonium graveolens L. under salinity stress

This research was carried out to evaluate the effect of two mycorrhiza species on growth, yield and oil content of geranium under salinity stress. The experiment was done at research greenhouse of Faculty of Agriculture, Lorestan University, Iran, in 2014. Four levels of substrate (sterilised and non-sterilised control soil and sterilised soil inoculated with Glomus mosseae or G. intraradices), and three levels of salinity (0, 30 and 60 mmol NaCl) were combined factorially based on a completely randomized design with three replications. Results showed significant differences at 0.05 probabilty level for plant height, stem diameter, number of lateral shoots, number of leaves, leaf area, root length, root volume, leaf fresh and dry weights, stem, root and shoot fresh weights, essential oil content and yield, relative water content and electrolyte leakage and at 0.01 probability level for number of nodes, root diameter, stem and root dry weights. The results showed that as salinity level increased, plant height, stem diameter, number of lateral shoots and leaves/plant, leaf area, leaf, stem and root fresh and dry weight, and oil yield decreased, while, oil content increased. Inoculation with both mycorrhiza species increased leaf relative water content, decreased electrilyte leackage and improved shoot yield, oil content and oil yield under salinity stress, so that, oil yield in plants treated with Glomus mosseae and G. intraradices were 41.9 and 56.8 percent hiegher compared with control, respectively. According to these results and due to environmental sustainability, application of mycorrhiza in substrate could be recommended to decrease the detrimental effects of salinity stress and increase plant yield in geranium.