Performance of Pot-Grown Seedlings of the Dipterocarp Dryobalanops lanceolata with Controlled-Release Fertilizer after Transplantation to the Shifting Cultivation Land in Sarawak, Malaysia

In the present study, the focus was placed on the survival, growth, nutrient status, and ectomycorrhizal formation of pot-grown dipterocarps treated with a controlled-release fertilizer or a chemical fertilizer when transplanted to abandoned shifting cultivation land. Either a chemical fertilizer (CF) or a 700-day controlled-release fertilizer (CRF) had been applied to Dryobalanops lanceolata seedlings at the rates of 0, 2, 5, and 10 g fertilizers per pot in the nursery of the Forest Research Station Niah (FRSN), Miri, Sarawak, Malaysia. The seedlings were cultivated for 18 months in the nursery, and then transplanted to abandoned shifting cultivation land around the FRSN. At 16 months after transplantation, the plants in the CRF treatments showed a good performance in terms of growth and survival ability, because of the sufficient amounts of nutrients accumulated in plants with a sound shoot form and high photosynthetic activity at the nursery stage. On the other hand, many saplings in the CF treatments at the rates of 5 g and 10 g died in the field due to their spindly shoot form and low photosynthetic activity in the nursery, even though the saplings that survived showed on adequate growth. Therefore, the application of slow-release type CRF in the nursery was considered to be feasible and suitable for successful establishment of a dipterocarp plantation in the field. Ectomycorrhizal fungus present in the nursery would sustain and be correlated with P uptake of the saplings after transplantation.