Nutritional characteristics in leaves of native plants grown in acid sulfate,peat, sandy podzolic,and saline soils distributed in Peninsular Thailand

Acid sulfate soils, peat soils, sandy podzolic, and saline soils are widely distributed in Peninsular Thailand. Native plants adapted to such problem soils have grown well, and showed no symptom of mineral deficiency or toxicity. Dominant plants growing in low pH soils (acid sulfate and peat) were Melastoma marabathricum and Melaleuca cajuputi. Since M. marabathricum accumulated a huge amount of aluminum (Al) in leaves, especially in new growing leaves, it can be designated an Al accumulator plant. While M. cajuputi did not accumulate Al in shoot, it can be designated an Al excluder plant. Both plant species adapted well to low pH soils, though a different strategy was used for Al. On the other hand, in acid sulfate and peat soils, M. cajuputi, Panicum repens, Cyperus haspan, and Ischaemum aristatum accumulated large amounts of Na in the leaves (or shoots), even in soil with low exchangeable Na concentration. Thus, when growing in the presence of high Al and Na concentration in soils, plant species have developed two opposite strategies: (1) Al or Na accumulation in the leaf and (2) Al or Na exclusion from the leaf. Al concentration in leaves had a negative relationship with the other mineral nutrients except for N and Mn, and Na concentration in leaves also had a negative relationship with P, Zn, Mn, Cu, and Al. Consequently, Al and Na accumulator plants are characterized by their exclusion of other minerals from their leaves.