Seasonal Variation in N, P and K Content of Different Plant Parts in Tropical Deciduous Tree Species

Changes in the concentrations of N, Pand K were estimated at monthly intervals in the leaves, stems and roots of Ckukrasia tabularis, A. Juss. (Meliaceae), Dolichandrone atrovirens (Heyne ex Roth), Sprague (Bignoniaceae), Lannea coromandelica (Houtt) Merr. (Anacardiaceae), Terminalia arjuna (DC.) Wright & Am. (Combretaceae) and Terminalia bellerica (Gaertn.) Roxb. (Combretaceae) for a period of one year starting from June, 1990 to May, 1991 in all seven tropical deciduous tree saplinp. Levels of N, P and K in the leaves of these tree species showed high nutrient content during spring season (February-May) and decreased as the leaf age advances. Concentrations of N, P and K in the stems and roots decreased when growth was rapid and increased on cessation of growth. Seasonal variation of N, P and K was minimum in the roots compared to the leaves and stems. Concentrations of N, P and K varied from month to month and these differed from one plant species to the other. The results of the present study indicates the scope for screening and selecting the right type of tree species for energy plantations, which could be used as fuel wood.