Document Type : Research Paper
Assistant Professor, Department of Soil Science, College of Agriculture, Shiraz University, Shiraz, Iran
Former Graduate Student, Department of Soil Science, College of Agriculture, Shiraz University, Shiraz, Iran
A greenhouse experiment was performed in the framework of a completely randomized design and a factorial arrangement to evaluate the effect of Arbuscular Mycorrhizal Fungi (AMF) on growth and on root antioxidant enzyme changes of two citrus rootstocks (Sour orange and Rough lemon). The experimental factors were: mycorrhizal treatments at two levels (inoculation with Glomus mosseae vs. control) along with irrigation treatments, namely 4 irrigation intervals of 2, 4, 6 and 8 days each. As water deficit stress increased, shoot and root dry weights decreased, while Catalase (CAT), Super Oxide Dismutase (SOD) and Ascorbate PeroXidase (APX) activities, in roots, increased. Shoot and root dry weights, APX, CAT and SOD activities in roots of the two citrus rootstocks were higher in mycorrhizal vs. non mycorrhizal of two citrus rootstocks under well-watered and water deficit stress conditions. In mycorrhizal plants, root colonization decreased (up to 40%), with increase in the levels of water deficit stress.