Jurnal Penelitian Kelapa Sawit

Effect of Drought Stress on Vegetative Growth and Curvularia oryzae Leaf Spot Disease Severity on Oil Palm (Elaeis guineensis) Seedlings

Hari Priwiratama — 2025-08-26

Drought stress is one of the factors that may influence the growth of oil palm seedlings. In long term, drought can potentially increase the susceptibility of oil palm to plant diseases. This study aims to analyze the effect of drought on vegetative growth and the severity of Curvularia leaf spot disease. Drought stress was simulated by limiting water application to three-month-old oil palm seedlings at field capacity (KL), 75% KL, 50% KL, and 25% KL levels. In each treatment, inoculation of Curvularia oryzae was conducted by spraying a spore suspension (1 x 10⁵ conidia/mL) evenly on the leaf surface. The results showed that infected seedlings under severe drought stress (25% KL) had lower height and crown width compared to treatments KL. The severity of Curvularia leaf spot disease in plants experiencing severe water stress (25% KL) was lower than in the standard nursery treatment, KL, and 75% KL. In general, it can be concluded that drought stress has contrasting effects on plant growth variables and the severity of Curvularia leaf spot disease.

Assessing the Sustainability Level of Oil Palm Smallholders Plantation Business using Application of RAPPO Method in Simalungun District, North Sumatra

Asma Nabila — 2025-08-26

The existence of smallholder oil palm plantations plays a central role in the growth of oil palm plantation area in Indonesia. However, smallholder oil palm plantations still face major challenges related to productivity and sustainability. This study aims to assess the sustainability level of certified and non-certified smallholder oil palm plantations in Simalungun District, North Sumatra, using the Rapid Appraisal for Palm Oil (RAPPO) method. The analysis was based on four dimensions of sustainability: economic, social, ecological and institutional. The results show that certified smallholders have a better level of sustainability compared to non-certified smallholders. The cumulative sustainability score for certified smallholders is 67.71 (moderately sustainable), while non-certified smallholders only reach 47.45 (less sustainable). The institutional dimension is a differentiating factor, where certified smallholders benefit from farmer groups and cooperatives in the form of counseling, market access, and the application of sustainable cultivation techniques. Therefore, efforts to strengthen institutions through increased participation in farmer groups and cooperatives, as well as continuous counseling, are strategic steps in improving the sustainability of smallholder oil palm plantation businesses in Simalungun District.

Morphological Response of Oil Palm Seedlings to Fertilizer Application

Ikhwan Fadli Pangaribuan — 2025-08-26

Oil palm requires a balanced and sufficient supply of nutrients to achieve optimal results. Elements such as nitrogen (N) and potassium (K) are the most essential macronutrients needed by the plant. The cost of fertilizer application is relatively high, which presents opportunities and challenges in assembling plant materials that are efficient in nutrient utilization. This research aims to investigate the responses of various populations of oil palm plants to fertilizer application treatments. The study was organized using a split-split plot design with three factors: fertilizer type [nitrogen (N1) and potassium (N2)], fertilizer dosage [0% (P0), 100% (P1), 75% (P2), and 50% (P3) of the recommended dosage], and plant material [populations 1-6 (V1-V6)], repeated six times. The treatment with the highest average plant height was observed in P2, where the fertilizer was applied at 75% of the recommended dosage. In contrast, the best fertilizer type and dosage combination was obtained from N1:P2, referring to plants treated with 75% of the recommended nitrogen fertilizer. Regarding the populations used, population V1 exhibited the lowest average plant height, significantly differing from other populations. When considering populations, the average leaf count of populations V2 and V6 significantly differed from others and had the highest averages. However, when considering the interaction with fertilizer type, the N2V6 interaction involving population six treated with potassium fertilizer showed the highest average leaf count and significantly differed from other interactions. Regarding stem diameter, populations V3, V2, V4, and V6 had the largest average stem diameters and significantly differed from V5 and V1. The treatment combinations N2P2V6 (crossing six treated with 75% potassium fertilizer) and N1P3V2 (population two treated with 50% nitrogen fertilizer) had the largest average stem diameters, measuring 8.14 cm and 8.07 cm, respectively. Both significantly differed from the other 46 interactions. On the other hand, the smallest average stem diameter was found in plants with the N2P3V1 interaction, measuring 5.33 cm, and significantly differed from the other 47 interactions.

The Impact of Enhancing CPO Productivity and Production Capacity in the CPO Downstream Industry on Indonesian Biodiesel Production

Indah Adelina Siregar — 2025-08-26

Biodiesel is an alternative fuel produced from palm oil processing. Based on production capacity, biodiesel is the second highest palm oil-derived product after cooking oil, at 11.4 million tons, cooking oil at 15.3 million tons, soap and detergent at 3.6 million tons, basic oleochemicals at 1.7 tons and margarine/shortening at 0.8 million tons (Ditjenbun 2019). With such downstream industry capacity, the domestic palm oil downstream industry is estimated to be able to process around 32 million tons of CPO. The simulation results show that the implementation of the DMO policy through an increase in palm oil demand by the biodiesel industry by 10% has an impact on increasing the domestic real price of palm oil by 0.006%, causing an increase in the domestic demand for Indonesian palm oil by 0.05% with an increase in palm oil demand by the biodiesel industry by 0.007%, palm oil demand by other industries by 0.001%. The increase in the DMO policy also impacts biodiesel production by 0.85% so that Indonesia's domestic biodiesel supply increases by 16.7%, biodiesel exports increase by 6.88% and there is a decrease in the domestic real price of biodiesel by 2.34%. The impact of increasing biodiesel production capacity is that the demand for biodiesel will increase so that the production of biodiesel raw materials, namely palm oil, will increase. With the increase in palm oil production, it will have an impact on the supply of palm oil and the government will export even higher.

R&D Expenditures and Firm Performance of Plantation Firms Listed on the Indonesia Stock Exchange (IDX), 2019–2023

M. Roby Yuliansyah — 2025-08-26

This study investigates the impact of R&D expenditure and firm characteristics on the financial performance of Indonesian plantation companies listed on the Indonesia Stock Exchange (IDX) from 2019 to 2023, using quantile regression analysis. Return on Equity (ROE) serves as the performance metric across the 25th, 50th, and 75th quantiles. The results show that R&D expenditure has a significantly negative effect at the median quantile, while Debt to Equity Ratio (DER) negatively affects ROE at both lower and median quantiles. Capital Intensity and Firm Size do not show significant effects, whereas Firm Age has a slight positive effect in the upper quantile. These findings suggest that while R&D investments may burden short-term profitability, they remain essential for long-term performance if managed strategically. The study highlights the importance of partnerships with credible R&D institutions, technological adoption, and government support to overcome sector-specific limitations. Limitations include the sector-specific focus and lack of qualitative dimensions, indicating the need for broader and mixed-method research in the future. Moreover, given the five-year observation period and limited sample size, the findings should be interpreted cautiously and are not intended to be generalized beyond the observed context.