Introduction Soil acidity is a major limitation to agricultural production throughout the world and one of the main causes of aluminium(Al) stress situations, with acidic soils representing about 50% of the total arable lands(Panda et al., 2009). Soil acidification is a nat- ural process that is accelerated by some crop production practices. The main causes of soil acidity include(i) organic matter decay which produces hydrogen ions(H(ii) crop absorption of lime- like elements such as mono and bivalent cations(K Ca2 Mg2. and(iii) the use of ammoniacal fertilizers: a these processes have