Effect of mychorhizal symbiosis on growth properties and colonization of common Almond rootstock at water deficit conditions

Drought is one of the most important environmental stresses that adversely affect the plant growth and crop production. Arbuscular mycorrhizae fungi help their host by absorption of water and mineral nutrition. In order to evaluate mycorrhizal fungus and water deficit stress on growth characteristics, chlorophyll content and root colonization percentage of almond (Prunus amygdalus) rootstock, a completely randomized design with factorial arrangement was conducted with three replications in agricultural and natural research center of Shahrekoard. The treatments consist of two levels of mycorrhizal fungus (with (M1) and without (M0) mycorrhizal fungus), four types of rootstock (bitter, local Shorab 2, GF and GN) and four levels of water deficit stresses (Control (I0), slight (I1), moderate (I2) and severe (I3)). The results revealed that the rootstock types had significant effects on studied parameters and the maximum measured parameters was observed in GF rootstock treatment. Water deficit stress also had significant effects on examined parameters. With increasing water deficit stress, root colonization percentage and root dry weight decreased significantly. Mycorrhizae fungi treatments increased root dry weight and root colonization percentage 27 and 40 percent respectively. The maximum stem length, stem diameter and plant dry weight were observed in GF +I1 treatment. The highest amount of root colonization percentage (74.5 %) was achieved in I1 + M1 treatment. Therefore, based on the results, the mycorrhizal fungus increased the growth properties of almond rootstock and reduced the harmful effects of water deficit stress.