Contributions of Arbuscular Mycorrhizal Fungi to Growth, Biomass and Nutrient Status of Pistachio Seedlings under Saline Conditions

Abstract

Excessive salt accumulation in soil is a major ecological and agronomical problem, especially in arid and semiarid areas. Excessive soil salinity affects the establishment, development and growth of plants, resulting in major losses of production. A pot experiment was set up to examine the effects of arbuscular mycorrhizal fungus (<em>Glomus etunicatum</em> and <em>Glomus versiforme</em>) and salinity on the growth, pigment concentration, biomass and nutrient acquisition of pistachio (<em>Pistacia vera</em> L.) seedlings. Two-month-old pistachio seedlings colonized by <em>G. etunicatum</em> and <em>G. versiforme</em> were irrigated with 0 and 150 mM NaCl solution for 45 days to induce salt stress. The results showed that salt stress significantly reduced mycorrhizal colonization in pistachio seedlings, and <em>G. versiforme </em>was found to be more colonized than <em>G. etunicatum</em>. Mycorrhizal inoculation, especially<em> G. versiforme, </em>had higher plant growth, biomass and pigment content than non-mycorrhizal under control and salt stress treatments. Shoot Na concentrations were lower in mycorrhizal than in non-mycorrhizal seedlings under given salinity conditions. Total P, K, N, Ca macronutrients and micronutrients decreased with soil salinity in both mycorrhizal and non-mycorrhizal seedlings. These nutrients were higher in AM, especially <em>G. versiforme</em>, than in NM seedlings in control and salt stress treatment. The results suggested that mycorrhizal, especially<em> G. versiforme,</em> pistachio plants exhibited greater efficiency in alleviating salt stress, which resulted in better growth.