Role of mycorrhizal fungi and salicylic acid in salinity tolerance of Ocimum basilicum resistance to salinity
Salinity is one of the common agricultural and biological problems. Most researchers showed that inoculation of plants with mycorrhizal fungi and using salicylic acid increase tolerance of plants due to salinity. In this study, the effect of mycorrhizal fungi, including Glomus mosseae, Glomus intraradices, and salicylic acid (0.2 mM) on tolerance of green basil (Ocimum basilicum L.) to salinity resulting from sodium chloride (75 and 150 mM) was compared and considered. The results show that salinity caused reduction of root inoculation of plants with G. mosseae, and against increased malondialdehyde (MDA), other aldehydes, reduced sugars and proline in aerial organs and protein in aerial organs and root. In salinity conditions, sodium content increased in aerial organs and root of basil plant, which is an indicator of damage resulting from salinity. In pretreatment of plants with salicylic acid (0.2 mM), lipid peroxidation was decreased; proline and protein content in aerial organs and root, reduced sugars of root and potassium in aerial organs were increased. Mycorrhizal inoculation decreased lipid peroxidation and increased reduced sugars, proline, protein and potassium contents in aerial organs and roots. In comparison of mycorrhizal inoculation and SA pretreatment, it was observed that effect mycorrhizal inoculation on increase proline, protein and potassium in aerial organs and root and on decrease in sodium of aerial organs was more intensive than salicylic acid. On the other hand, the effect of salicylic on increase in proline of aerial organs and on decrease in potassium of root relative to inoculated plants with mycorrhizae was more intensive. Based these results, it can be concluded that the effect of inoculating plants with mycorrhizae relative to salicylic acid causes a better resistance in basil plant relative to tension of salinity.
Key words: Mycorrhizal fungi, salicylic acid, Ocimum basilicum.