Effect of Plant Aging on Root Development of Sago Palm (Metroxylon sagu Rottb.) Grown in Tebing Tinggi Island, Riau Province and in Kendari, Southeast Sulawesi in Indonesia

Abstract

The effect of plant aging on the root development of sago palm was investigated in both Tebing Tinggi Island, Riau (deep peat soil area) and in Kendari, Southeast Sulawesi (mineral soil area), Indonesia. The results were as follows: 1) Value of root dry weight was higher at the central position (0 m from a main stem or trunk) than that at positions 1 and 2 m from the main stem or trunk, and was higher at soil depths of 0 to 30 cm than 30 to 60 cm and 60 to 90 cm in both regions. 2) Sago palm roots in both regions started to increase horizontally before the trunk formation stage, while after trunk formation, the roots increased vertically as aging progressed, and expanded downwards. 3) Root dry weight value in Kendari was significantly higher than in Tebing Tinggi. However, a higher percentage of dead roots and a lower percentage of small roots were found in Kendari than in Tebing Tinggi, especially in deep soil layers in younger palms. In Kendari, the roots were more concentrated in the upper soil layers than in Tebing Tinggi after the trunk formation. This last result may be associated with the soil hardness due to high bulk density and low nutrient levels in deep soil layers of mineral soils.