Growth and nutrient uptake of haloxylon and atriplex as affected by mycorrhizal symbiosis under combined drought and salinity stresses

Abstract

This study was conducted to determine the effect of arbuscular mycorrhizal fungi (AMF) symbiosis on plant growth and nutrient uptake under combined drought and salinity stresses. A pot experiment was carried out with a factorial arrangement of treatments in a completely randomized design with three replications. Experimental treatments included two plant types ( Atriplex canescens and Haloxylon ammodendron) with three levels of inoculation of fungal species ( Funneliformis geosporus, Funneliformis mosseae, and control), two levels of soil salinity stress (7 and 14 dS m–1), and two levels of drought stress (50% and 80% of management allowable depletion). Vegetative parameters, as well as root N, P, and K concentrations and uptakes, mycorrhizal growth response, mycorrhizal nitrogen response, mycorrhizal phosphorus response, mycorrhizal potassium response, and root colonization were measured. The results showed that the application of AMF increased the plant growth variables such as stem diameter, root length, shoot dry weights, and shoot to root ratio as well as nitrogen and phosphorus uptakes. The application of both AMF types was effective as compared to the control. However, F. mosseae indicated better performance especially, in terms of the effect on plant growth variables. Also, F. mosseae was more effective to relieve stress (i.e., salinity and drought) than F. geosporus. There was a significant difference between plant types and H. ammodendron had better efficiency than A. canescens under drought and salinity stresses. Based on the results, planting of H. ammodendron inoculated with F. mosseae might be recommended for soil conservation in the arid environments.