Effects of Mycorrhiza on Plant Nutrition, Enzyme Activities, and Lipid Peroxidation in Pepper Grown Under Salinity Stress

This study was conducted to determine whether Arbuscular Mycorrhizal Fungi (AMF) [ROOTS-novozymes endo-mycorrhiza fungus (Glomus spp.)] increase salt stress tolerance. The effects of mycorrhiza inoculation and salt on root and stem development, mineral nutrition, enzyme activity and lipid peroxidation levels in pepper (Capsicum annuum L.) plant was investigated. These effects were explored in pepper plants grown under greenhouse conditions in a randomized block design. Four different doses of salt (۰, ۵۰, ۱۰۰ and ۱۵۰ mM NaCl) were applied to the soil-filled pots, in addition to two different doses of mycorrhiza (۰ and ۱۰۰ spore mycorrhiza plant-۱). It was found that the root and stem dry weights of pepper plants were greatly reduced in the non-mycorrhiza treatments, whereas the presence of mycorrhiza ameliorated these negative effects. N, P, K, Ca, Mg, S, Fe, Mn, Zn and Cu contents of AMF treated pepper were higher than non-mycorrhizal plants. Owing to the presence of AMF colonization, nutrient uptake was increased and, consequently, the nutrient contents of stem and root tissues of mycorrhizal inoculated plants were enhanced as well. On the other hand, the root and stem enzyme activity of plants increased with salinity. AMF inoculation decreased SOD, CAT, POD and AxPOD enzymes of plant and the MDA and H۲O۲ contents, indicating lower oxidative damage in the inoculated plants. Our results showed that AMF can contribute to protect plants against salinity by alleviating the salt induced oxidative stress and arranging the ion balance in plant via increasing nutrient uptake in saline soils.

Keywords:

Arbuscular mycorrhizal fungi , Nutrient uptake , Saline soils , Salt stress tolerance.