Response of two tomato cultivars differing in salt tolerance to inoculation with mycorrhizal fungi under salt stress

Effects of arbuscular mycorrhizal fungi (AMF) and salt stress on nutrient a cquisition and growth of two tomato cultivars exhibiting differences in sal t tolerance were investigated. Plants were grown in a sterilized, low-P (si lty clay) soil-sand mix. Salt was applied at saturation extract (ECe) value s of 1.4 (control), 4.9 (medium) and 7.1 dS m(-1) thigh salt stress). Mycor rhizal colonization occurred irrespective of salt stress in both cultivars, but AMF colonization was higher under control than under saline soil condi tions. The salt-tolerant cultivar Pello showed higher mycorrhizal colonizat ion than the salt-sensitive cultivar Marriha. Shoot dry matter (DM) yield a nd leaf area were higher in mycorrhizal than nonmycorrhizal plants of both cultivars. Shoot DM and leaf area but not root DM were higher in Pello than Marriha. The enhancement in shoot DM due to AMF inoculation was 22% and 21 % under control, 31% and 58% under medium, and 18% and 59% under high salin ity for Pello and Marriha, respectively. For both cultivars, the contents o f P, K, Zn, Cu, and Fe were higher in mycorrhizal than nonmycorrhizal plant s under control and medium saline soil conditions. The enhancement ill P, K , Zn, Cu, and Fe acquisition due to AMF inoculation was more pronounced in Marriha than in the Pello cultivar under saline conditions. The results sug gest that Marriha benefited more from AMF colonization than Pello under sal ine soil conditions, despite the fact that Pello roots were highly infected with the AMF Thus, it appears that Marriha is more dependent on AMF symbio sis than Marriha is Pello.