Implications of calcium nutrition on the response of Acacia senegal (Mimosaceae) to soil salinity

Abstract

Effects of Ca2+ level on the response of germination and seedling growth of Acacia senegal (L.) Willd. (Mimosaceae) to NaCl salinity in soil were investigated. Salinity significantly retarded the seed germination and seedling growth, but the injurious effects of NaCl on seed germination were ameliorated and seedling growth was restored with calcium supply at the critical level (1:0.75 Na/Ca ratio) to salinised soil. Calcium supply above the critical level further retarded the seed germination and seedling growth due to the increased soil salinity. Salt stress reduced N, P, K, Ca and Mg content in plant tissues, but these nutrients were restored by addition of calcium at the critical level to saline soil. The opposite was true for Na+. The results are discussed in terms of the beneficial effects of calcium supply on the seedling growth of this species under saline conditions.