ARBUSCULAR MYCORRHIZAL FUNGI ALLEVIATE SALT STRESS ON SWEET BASIL SEEDLINGS

Abstract

 Abiotic stress due to salinity is considered one of the main problems facing agriculture that has the detrimental effect of restricting the growth and development of plants. The objective of this study was to evaluate the effect of arbuscular mycorrhizal fungus species (Rhizophagus fasciculatum) as reliever of NaCl-stress in sweet basil seedlings in emergence stage. A completely randomized design with factorial arrangement with four replications was used; first factor was sweet basil varieties (Nufar, Genovese, and Napoletano), factor two were NaCl concentrations (0, 50, and 100 mM) and factor three was inoculation of seeds with Rhizophagus fasciculatum (+AMF) an arbuscular mycorrhizal fungi and non-inoculated seeds (−AMF). Chemical composition of the substrate, rate and emergence percentage, plant height, root length, fresh and dry biomass of aerial part and root, spore count, and colonization percentage were assessed. The results showed differences in all variables with Napoletano showing higher values of all variables at 0, 50 or 100 mM NaCl with AMF. Majority of variables decreased with NaCl concentrations. The substrate was suitable for growth of Rhizophagus fasciculatum and for sweet basil. No root colonization was found in any seedlings inoculated with AMF; however, the micrograph of the inoculated plants showed vegetative mycelium, a mycorrhizal structure that shows the initiation of the colonization process.