Effects of Arbuscular Mycorrhizal Symbiosis on Growth and Some Physiological and Eco-physiological Properties of Two rootstocks of Almond (GF677 and Shurab 2) Under Drought Stress

To investigate the effects of mycorrhizal symbiosis on growth and some physiological and eco-physiological properties of almond rootstocks in drought stress¡ a factorial experiment in a completely randomized design with three factors including four mycorrhiza (without mycorrhiza¡ Glomus mosseae¡ G. intraradices and a mixture of two species)¡ three levels of drought (Daily¡ 3 and 6 days irrigation intervals)¡ two almond rootstocks (Shurab 2 and GF677) were performed in 3 replicate.The results showed that interactions of mycorrhizal fungi species¡ drought levels and almond rootstock had significant effect on growth parameters like root and shoot dry weight¡ length of root system¡ shoot height¡ leaf area¡ number of leaves and mycorrhizal colonization percentage. Application of mycorrhizae increased plants growth compared to control plants. In response to drought stress¡ osmotic regulation processes were actived in almond rootstocks. Proline and soluble sugars of plant leafincreased¡ but this process in leaves of mycorrhizal plants was less than mycorrhizal plants. In general¡ the results of this study showed that the Shurab 2 rootstock is more resistant to drought stress than the GF677. Plant mycorrhizal were less affected by the drought stress.