Palm Cultivation Research Articles

Transforming oil palm trunk waste into high-performance lightweight materials

Addressing the growing demand for efficient sustainable materials, this study presents the development of a high-performance lightweight material utilizing oil palm trunk—a waste product from oil palm (Elaeis guineensis) cultivation. The proposed novel process involves polymer impregnation of sawn oil palm trunk under ambient conditions for 24-h soaking intervals, resulting in loadings of polymethyl methacrylate ranging from 0 wt% to 220 wt%. Subsequent polymerization at temperatures (90 and 103°C) commonly employed in the wood drying industry enhances the water resistance of the material, making it comparable to that of commercially available timber. Remarkably, the treated oil palm lumber attained a maximum density of approximately 450 kg/m3, making it a lightweight material. Furthermore, the impregnation process significantly improves the decay resistance of this product under natural weathering conditions. The treated oil palm lumber also displayed an increase of up to five times in the bending and compressive strength. Interestingly, a linear correlation between these enhanced properties and the density of this material was observed. This suggests the possibility of systematically producing the high-performance oil palm lumber through a simple and industry-accessible process.

Site occupancy of native terrestrial mammals in oil palm landscapes is driven by the synergy of land sparing and sharing strategies

The conversion of tropical rainforests into industrial oil palm monocultures has detrimental effects of local biodiversity. Although some medium-sized mammals have demonstrated a degree of adaptability in oil palm landscapes, the factors that influence their ability to persist in such human-altered environments remain obscure. Here, we investigated the site occupancy and activity pattern of the mammals in oil palm landscapes in Peninsular Malaysia. We deployed 81 camera traps throughout six oil palm cultivation areas with two distinct management styles (three sites each in organized smallholdings and industrial plantations). Smallholdings had higher site occupancy of native animal species than industrial plantations. The site occupancy of the mammals was influenced by the proximity to continuous forest, forest patches and riparian vegetation. Landscape metrics are characteristics that affect land sparing strategy, allowing wildanimals in agricultural landscapes to thrive in their habitat despite human threats. At stand-level, the detection of animals was determined by elevation, undergrowth vegetation cover/height, canopy cover, oil palm height, quantity of oil palm fruits, and prune stack thickness. Mammal occupancy was higher in the smallholdings due to the proximity to continuous forest. We recommend improving landscape heterogeneity and connectivity in oil palm matrix to promote species mobility and diversifying oil palm management away from monoculture farming. Our findings indicate that incorporating land sharing and sparing strategies into the oil palm matrix is necessary to conserve biodiversity and maintain ecological services. This implies that industry stakeholders ought not to disregard either land sparing or land sharing.

Oil Palm Bunch Ripeness Classification and Plantation Verification Platform: Leveraging Deep Learning and Geospatial Analysis and Visualization

Oil palm cultivation thrives as a prominent agricultural endeavor within the southern region of Thailand, where the country ranks third globally in production, following Malaysia and Indonesia. The assessment of oil palm bunch ripeness serves various purposes, notably in determining purchasing prices, pre-harvest evaluations, and evaluating the impacts of disasters or low market prices. Presently, two predominant methods are employed for this assessment, namely human evaluation, and machine learning for ripeness classification. Human assessment, while boasting high accuracy, necessitates the involvement of farmers or experts, resulting in prolonged processing times, especially when dealing with extensive datasets or dispersed fields. Conversely, machine learning, although capable of accurately classifying harvested oil palm bunches, faces limitations concerning its inability to process images of oil palm bunches on trees and the absence of a platform for on-tree ripeness classification. Considering these challenges, this study introduces the development of a classification platform leveraging machine learning (deep learning) in conjunction with geospatial analysis and visualization to ascertain the ripeness of oil palm bunches while they are still on the tree. The research outcomes demonstrate that oil palm bunch ripeness can be accurately and efficiently classified using a mobile device, achieving an impressive accuracy rate of 99.89% with a training dataset comprising 8779 images and a validation accuracy of 96.12% with 1160 images. Furthermore, the proposed platform facilitates the management and processing of spatial data by comparing coordinates derived from images with oil palm plantation data obtained through crowdsourcing and the analysis of cloud or satellite images of oil palm plantations. This comprehensive platform not only provides a robust model for ripeness assessment but also offers potential applications in government management contexts, particularly in scenarios necessitating real-time information on harvesting status and oil palm plantation conditions.

Agricultural land use policies and landscape dynamics: Evidence from rainforest agroecological zone

Agricultural-land use policies play a crucial role in shaping agroecological landscapes globally. The evidence suggests that some of these policies tend to have undesired feedback/trade-offs, particularly about coastal resource use and conservation planning. The present study explores how agricultural policies influence land use/land cover (LULC) transition patterns in Ghana's Rain Forest Agroecological Zone (RFAZ). Landsat satellite images for 1991, 2008, and 2022 were acquired for the LULC mapping. Change detection and Intensity analysis were used to assess the pattern of land change. Also, documentary research processes were used to review and assess agricultural land use policies. The results showed that before rubber-related policy implementation, oil palm plantation was the dominant LULC type in the 1990 s. In the 1990 s and early 2000 s, there was a conscious government drive to leverage oil palm plantation development. This led to the growth in the size of oil palm plantations within the RFAZ landscape, considering the zone’s conducive natural environment. However, between 2008 and 2022, corresponding to the period of the increased promotion of rubber cultivation through the Outgrower project in the RFAZ, rubber plantations became the predominant land use, with an area of 11,763.81 ha in 2008 and 21,611.61 ha in 2022. The results from the LULC mapping and the intensity analysis showed that the Rubber Outgrowers Plantation Project (ROPP) and Norpalm Smallholder Scheme Project (NSSP) have degraded the natural cover through rubber and oil palm cultivation. The authors conclude that landscape dynamics, particularly in rainforest agroecological zones, represent a nexus challenge transforming policy adaptation's discursive context. The study recommends that agriculture and landscape policy/projects must have/take intermediary steps to address the feedback/trade-offs from well-intended initiatives. The study further suggests that management plans and strategies in the RFAZ should be consistent with the strict protection of forest reserves and water bodies.

Assessing the efficacy of utilizing biochar derived from oil palm biomass as a planting medium for promoting the growth and development of oil palm seedlings

The recent adoption of biochar in Malaysia's oil palm industry offers numerous benefits, including soil enhancement, resource efficiency improvement, pollution remediation, and greenhouse gas mitigation. With approximately 66.15% of agricultural land dedicated to oil palm cultivation, a substantial amount of biomass, mainly from empty fruit bunch (EFB) and mesocarp fibre (MF), is generated. This study focused on carbonizing MF and EFB at temperatures ranging from 580 to 695 °C to produce biochar. The assessment of biochar's effectiveness as a planting medium in nurseries revealed significantly accelerated growth rates in seedlings cultivated in a composite of biochar and soil. At 8 months-after-treatment (MAT), the BMF-75 treatment showed remarkable growth enhancements, with the highest increase in height (64.9%), number of leaflets (60.5%), and girth size (55.3%) compared to the initial values at 3 MAT, indicating its effectiveness in promoting growth in oil palm seedlings. Additionally, compared to the control group, the biochar-mixed media resulted in favourable outcomes regarding the assimilation of both macro- and micro-nutrients. For instance, nitrogen uptake increased by 2.7% with BMF-50, magnesium by 25.2%, phosphorus by 24.1% with BEFB-75, calcium by 36.8% with BMF-75, chlorine by 10.5% with BMF-50, iron by 25.5% with BEFB-25, copper by 20.1% with BMF-25, and zinc by 6.3% with BMF-25. Additionally, biochar-treated soil exhibited higher organic carbon content, improved cation exchange capacity (CEC), enhanced nitrogen retention with greater biochar proportions, and likely improved soil fertility due to biochar's porous structure. Further potential research can be explored to investigate its long-term effects on oil palm plantation.

Deorphanizing an odorant receptor tuned to palm tree volatile esters in the Asian palm weevil sheds light on the mechanisms of palm tree selection

The Asian palm weevil, Rhynchophorus ferrugineus, is a tremendously important agricultural pest primarily adapted to palm trees and causes severe destruction, threatening sustainable palm cultivation worldwide. The host plant selection of this weevil is mainly attributed to the functional specialization of odorant receptors (ORs) that detect palm-derived volatiles. Yet, ligands are known for only two ORs of R. ferrugineus, and we still lack information on the mechanisms of palm tree detection. This study identified a highly expressed antennal R. ferrugineus OR, RferOR2, thanks to newly generated transcriptomic data. The phylogenetic analysis revealed that RferOR2 belongs to the major coleopteran OR group 2A and is closely related to a sister clade containing an R. ferrugineus OR (RferOR41) tuned to the non-host plant volatile and antagonist, α-pinene. Functional characterization of RferOR2 via heterologous expression in Drosophila olfactory neurons revealed that this receptor is tuned to several ecologically relevant palm-emitted odors, most notably ethyl and methyl ester compounds, but not to any of the pheromone compounds tested, including the R. ferrugineus aggregation pheromone. We did not evidence any differential expression of RferOR2 in the antennae of both sexes, suggesting males and females detect these compounds equally. Next, we used the newly identified RferOR2 ligands to demonstrate that including synthetic palm ester volatiles as single compounds and in combinations in pheromone-based mass trapping has a synergistic attractiveness effect to R. ferrugineus aggregation pheromone, resulting in significantly increased weevil catches. Our study identified a key OR from a palm weevil species tuned to several ecologically relevant palm volatiles and represents a significant step forward in understanding the chemosensory mechanisms of host detection in palm weevils. Our study also defines RferOR2 as an essential model for exploring the molecular basis of host detection in other palm weevil species. Finally, our work showed that insect OR deorphanization could aid in identifying novel behaviorally active volatiles that can interfere with weevil host-searching behavior in sustainable pest management applications.

Agribusiness as a device for territorial control: the case of oil palm plantations in María La Baja, Colombia

Over the past four decades, the scale and number of oil palm plantations in Colombia have risen and these plantations have become a pillar of the country’s agricultural sector. This article examines the territorial control function of plantations, especially in areas where the expansion of palm cultivation has been a simultaneously novel and accelerated phenomenon. The Colombian government has encouraged the growth of this crop through three often overlapping models: dispossession, productive alliances, and the establishment of Zones of Rural, Economic and Social Development Interest (ZIDRES). This paper is based on fieldwork data from María La Baja in the Department of Bolivar, and focuses on the consequences of the productive alliance model as a novel form of territorial disciplining and control.

Dynamic analysis and optimal control strategies of a predator–prey mathematical model for the pest eradication in oil palm plantation

Oil palm cultivation stands as a crucial industry in Indonesia, significantly contributing to the nation’s economy by generating employment opportunities and fostering social welfare for communities residing near plantations. Despite its economic importance, oil palm plantations face various challenges, with one prominent issue being the infestation of nettle caterpillar pests. These pests cause leaf skeletonization, resulting in a staggering 36% reduction in oil palm productivity over a two-year period. This paper explores diverse strategies for pest management in oil palm plantations, encompassing biological control through the stimulation of natural predators, mechanical control involving the collection and incineration of cocoons, and chemical control through pesticide application. The research introduces a predator–prey mathematical model for oil palm plantation pests, where the leaf area serves as the primary food source for caterpillars, acting as prey. Through dynamic model analysis, four equilibrium points are identified, with interconnected conditions dictating their existence and stability. These conditions are visually represented in a bifurcation plane, providing concise information. The study further includes bifurcation diagrams of equilibrium points to elucidate the influence of each parameter on pests, predators, and the leaf area of oil palm plants. Additionally, sensitivity analysis of the stable interior equilibrium point is conducted to understand the impact of individual parameters. The paper extends its investigation to optimal control strategies, evaluating six scenarios categorized into two population conditions: with predators and without predators. Within each population condition, three control strategies are considered—chemical control only, mechanical control only, and a combination of chemical and mechanical control. Simulation results from the optimal control study reveal that the presence of natural predators emerges as a pivotal strategy in effectively managing nettle caterpillars. Notably, the control of resistant pests through pupa incineration has a substantial impact on reducing the caterpillar population in subsequent life cycles.

Balancing economic and ecological functions in smallholder and industrial oil palm plantations

The expansion of the oil palm industry in Indonesia has improved livelihoods in rural communities, but comes at the cost of biodiversity and ecosystem degradation. Here, we investigated ways to balance ecological and economic outcomes of oil palm cultivation. We compared a wide range of production systems, including smallholder plantations, industrialized company estates, estates with improved agronomic management, and estates with native tree enrichment. Across all management types, we assessed multiple indicators of biodiversity, ecosystem functions, management, and landscape structure to identify factors that facilitate economic-ecological win-wins, using palm yields as measure of economic performance. Although, we found that yields in industrialized estates were, on average, twice as high as those in smallholder plantations, ecological indicators displayed substantial variability across systems, regardless of yield variations, highlighting potential for economic-ecological win-wins. Reducing management intensity (e.g., mechanical weeding instead of herbicide application) did not lower yields but improved ecological outcomes at moderate costs, making it a potential measure for balancing economic and ecological demands. Additionally, maintaining forest cover in the landscape generally enhanced local biodiversity and ecosystem functioning within plantations. Enriching plantations with native trees is also a promising strategy to increase ecological value without reducing productivity. Overall, we recommend closing yield gaps in smallholder cultivation through careful intensification, whereas conventional plantations could reduce management intensity without sacrificing yield. Our study highlights various pathways to reconcile the economics and ecology of palm oil production and identifies management practices for a more sustainable future of oil palm cultivation.

Improving seed palm germination using biomaterials Fenugreek seed extract (Trigonella foenum-graecum L.)

The Barhee cultivar of date palm (Phoenix dactylifera) holds significance due to its nutritional value. This study explores the impact of Fenugreek (Trigonella foenum graecum L.) seed extract on the growth of Barhee seedlings. Gas Chromatography-Mass Spectrometry (GC-MS) analysis of Fenugreek seed extract at various concentrations (0.0%, 0.5%, 1%, 1.5%, 2%) revealed pronounced effects on the vegetative growth and phytochemical composition of Barhee seedlings. Our findings demonstrate a positive correlation between the Fenugreek seed extract treatments and the growth parameters of Barhee seedlings, particularly noteworthy when concentrations were below 2%. Notably, chlorophyll content increased by 58%, while soluble carbohydrates and proteins saw improvements of 55% and 48%, respectively. The antioxidant activity, measured through catalase (CAT) and superoxide dismutase (SOD), also exhibited enhancements. Phenolic compounds registered a substantial increase of 47%. Moreover, Fenugreek seed extract contributed to membrane integrity by reducing levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA), indicating a positive impact on oxidative stress. These results collectively underscore the beneficial effects of Fenugreek seed extract on the growth and physiological aspects of Barhee date palm seedlings. In conclusion, this study highlights the potential of Fenugreek as a growth-enhancing agent for date palm cultivation, specifically the Barhee variety. The positive outcomes observed in various parameters suggest that incorporating Fenugreek seed extract at appropriate concentrations could be a valuable strategy for optimizing the productivity and quality of date palm crops.

Regimes of global and national oil palm cultivations from 2001 to 2018

Oil palm is the dominant global oil crop due to its high productivity and diversified usage in many sectors. Since the late 20th century, oil palm cultivations proliferated in Southeast Asia, West Africa, and Latin America. However, global market factors, different national and regional policies, and smallholder versus commercial planting regimes in different areas lead to significant differences in economic benefits and environmental problems from deforestation and loss of biodiversity. We investigated changes in global and national distributions against suitability and indices of tree age distribution change for industrial oil palm (IOP) and smallholder oil palm (SOP). Spatial and temporal change analyses show that: i) For most tree ages, the proportion of global oil palm planting in suitable areas was less than 50%, but the impact of temporal regimes, from possible market factors and local policies, on planting structure should not be neglected; ii) Central America, South America, and West Africa were less suitable for oil palm cultivation compared to Southeast Asia. While, as two dominant oil palm planting countries, Indonesia and Malaysia had relatively low planting suitability, with 39.23% of Indonesia’s IOP, 44.85% of Indonesia’s SOP, 30.90% of Malaysia’s IOP and 18.77% of Malaysia’s SOP in highly and most suitable intervals; iii) There exist clear differences between IOP and SOP in terms of suitability, planting structure and spatial expansion patterns; iv) Hysteresis effect exists between latecomers (countries in West Africa and Latin America) and forerunner (Indonesia and Malaysia) in terms of spatial expansion; v) The spatial expansion patterns of oil palm planting centers have obvious scale effects for both IOP and SOP, with clear inter-country and intra-country differences. This paper reinterprets the global distribution of tree age and spatial expansion pattern and recommends scientific strategies to guide site selection and planting structure that enable oil palm cultivation for sustainable development.

Harnessing rhizospheric core microbiomes from arid regions for enhancing date palm resilience to climate change effects.

Date palm cultivation has thrived in the Gulf Cooperation Council region since ancient times, where it represents a vital sector in agricultural and socio-economic development. However, climate change conditions prevailing for decades in this area, next to rarefication of rain, hot temperatures, intense evapotranspiration, rise of sea level, salinization of groundwater, and intensification of cultivation, contributed to increase salinity in the soil as well as in irrigation water and to seriously threaten date palm cultivation sustainability. There are also growing concerns about soil erosion and its repercussions on date palm oases. While several reviews have reported on solutions to sustain date productivity, including genetic selection of suitable cultivars for the local harsh environmental conditions and the implementation of efficient management practices, no systematic review of the desertic plants' below-ground microbial communities and their potential contributions to date palm adaptation to climate change has been reported yet. Indeed, desert microorganisms are expected to address critical agricultural challenges and economic issues. Therefore, the primary objectives of the present critical review are to (1) analyze and synthesize current knowledge and scientific advances on desert plant-associated microorganisms, (2) review and summarize the impacts of their application on date palm, and (3) identify possible gaps and suggest relevant guidance for desert plant microbes' inoculation approach to sustain date palm cultivation within the Gulf Cooperation Council in general and in Qatar in particular.

Towards an Annually Updated Oil Palm Age Database (OPAD) with Multimodal Remote Sensing Features: Design and Preliminary Result

The cultivation of oil palm (Elaeis guineensis) is globally significant, particularly in tropical regions, due to the diverse applications of palm oil and palm kernel oil. This necessitates precise monitoring for sustainable management amidst escalating demand. This study aims to develop an annually updated Oil Palm Age Database (OPAD) using multisource remote sensing data to predict the oil palm age, a critical factor affecting productivity and environmental sensitivity. By comprehensively analyzing multisource remote sensing data from 1982 to 2023, this study establishes OPAD and validates its reliability using a random forest classifier. The findings reveal the relationship between remote sensing data features and changes in the oil palm age, offering insights into sustainable management practices. The results indicate an overall accuracy of 86.86 ± 0.92% for grouped age (i.e., seed (1-2 years), young (3-8 years), teen (9-14 years), mature (15-25 years), and post-mature (over 25 years)), with features such as GEDI forest height, ScanSAR HH SAVG, Planet NIR, and Planet Blue being instrumental in age prediction. Integrating optical, synthetic aperture radar (SAR), and canopy height data enables effective age prediction, which is essential for optimizing management strategies, assessing yield potential, and mitigating environmental impacts.

Impact of Organic and Chemical Fertilizer Combinations on Growth, Yield, and Soil Carbon in in Oil Palm Cultivation at Talgaswella Estate, Sri Lanka

The success of oil palm cultivation hinges on factors such as planting material quality, management practices, and the availability of essential macro and micro-nutrients. Insufficient nutrient supply adversely impacts both vegetative growth and the ultimate yield in terms of quantity and quality. To address this issue, an experiment was conducted at Talgaswella Estate, belonging to Elpitiya Plantations PLC., situated in the Low Country Wet Zone (LCWZ) of Sri Lanka. The objective was to enhance the productivity and profitability of marginal oil palm lands. A ten-year-old oil palm field was chosen as the experimental site, employing a Randomized Complete Block Design (RCBD) with eleven treatments and three replicates, including an absolute control. Each trial plot consisted of six palm trees, totaling 198 trees in the experiment. Treatments involved varying combinations of Empty Fruit Bunches (EFB), Palm Oil Mill Effluent (POME), and Poultry Litter (PL), with and without chemical fertilizer. Soil, plant, and yield parameters were measured, and the data were analyzed using the Minitab statistical tool. After three years, results indicated that 100% organic fertilizer-received plots (T11) and 100% chemical fertilizer-treated plots (T2) exhibited significant increases in average fresh fruit bunch weight (22.81 Kg and 21.82 Kg), soil organic carbon percentage (3.00 and 2.23), and leaf chlorophyll content (78.79 and 75.07) of the 17th frond compared to T11 and T2 treated plots. Intermediate results were observed in the remaining fertilizer combined plots (T3, T4, T5, T6, T7, T8, T9, T10). The findings suggest that the use of organic fertilizer in marginal oil palm lands not only improves crop and soil factors but also contributes to environmental sustainability through the recycling of oil palm waste products. It is recommended to periodically apply organic fertilizer, especially on marginal oil palm lands, to enhance overall crop productivity and land sustainability.

Higher avian biodiversity, increased shrub cover and proximity to continuous forest may reduce pest insect crop loss in small‐scale oil palm farming

Abstract One of the key ecosystem services offered by avian biodiversity within agricultural landscapes is natural predation. Nonetheless, the current use of biological control agents such as farmland birds in oil palm plantations is relatively limited. This study aimed to assess the potential roles of avian biodiversity, particularly insectivores that provide natural predation against oil palm herbivorous insects. We also investigated the influence of local‐ and landscape‐scale variables on foliage damage (crown or frond). Our data showed that crown damage decreased with increasing farmland bird richness (overall and insectivore), shrub cover, dried biomass and elevation, but increased with epiphyte cover, oil palm height and distance to continuous forest. Frond damage was negatively related to bird richness (overall, insectivore and non‐insectivore) and non‐insectivore abundance, elevation and shrub cover, while increased with insectivorous abundance, epiphyte cover, oil palm height and distance to continuous forest. We also found that plantations (≥50 ha) were more susceptible to foliage damage from pest insects than smallholdings (<50 ha). There was no evidence that indicate the influence of forest patches on foliage damage. Synthesis and applications. Our study highlights the economic value of conserving biodiversity, most notably, farmland birds and continuous forests with respect to biological control of defoliating pests and maintaining yield productivity in oil palm cultivation. Growers, particularly major plantation companies should make oil palm farming more biodiversity‐friendly in order to increase the number of biological control agents such as birds.

The socioecological benefits and consequences of oil palm cultivation in its native range: The Sustainable Oil Palm in West Africa (SOPWA) Project

Agriculture is expanding rapidly across the tropics. While cultivation can boost socioeconomic conditions and food security, it also threatens native ecosystems. Oil palm (Elaeis guineensis), which is grown pantropically, is the most productive vegetable oil crop worldwide. The impacts of oil palm cultivation have been studied extensively in Southeast Asia and – to a lesser extent – in Latin America but, in comparison, very little is known about its impacts in Africa: oil palm's native range, and where cultivation is expanding rapidly. In this paper, we introduce a large-scale research programme – the Sustainable Oil Palm in West Africa (SOPWA) Project – that is evaluating the relative ecological impacts of oil palm cultivation under traditional (i.e., by local people) and industrial (i.e., by a large-scale corporation) management in Liberia. Our paper is twofold in focus. First, we use systematic mapping to appraise the literature on oil palm research in an African context, assessing the geographic and disciplinary focus of existing research. We found 757 publications occurring in 36 African countries. Studies tended to focus on the impacts of palm oil consumption on human health and wellbeing. We found no research that has evaluated the whole-ecosystem (i.e., multiple taxa and ecosystem functions) impacts of oil palm cultivation in Africa, a knowledge gap which the SOPWA Project directly addresses. Second, we describe the SOPWA Project's study design and—using canopy cover, ground vegetation cover, and soil temperature data as a case study—demonstrate its utility for assessing differences between areas of rainforest and oil palm agriculture. We outline the socioecological data collected by the SOPWA Project to date and describe the potential for future research, to encourage new collaborations and additional similar projects of its kind in West Africa. Increased research in Africa is needed urgently to understand the combined ecological and sociocultural impacts of oil palm and other agriculture in this unique region. This will help to ensure long-term sustainability of the oil palm industry—and, indeed, all tropical agricultural activity—in Africa.

The effectiveness of isopropylamine glyphosate 486 g/L + metsulfuron methyl 1 g/L herbicidal combination in oil palm (Elaeis guineensis)

Lack of knowledge in weed control techniques in oil palm cultivation practices can lead to decreased productivity. One of the herbicides that can be used to control weeds in oil palm cultivation is a mixed herbicide made from isopropylamine glyphosate 486 g/L and methyl metsulfuron 1 g/L. The use of mixed herbicides with two or more active ingredients can broaden the spectrum of weed control, reduce herbicide residues, slow the emergence of herbicide-resistant weeds, and reduce production costs. Therefore, this study aims to determine the effectiveness of mixed herbicides IPA glyphosate 486 g/L and methyl metsulfuron 1 g/L in controlling weeds in oil palm plants in the producing phase. This research was conducted at Bukit Nyomot oil palm plantation Subang Regency, Jawa Barat Province from February to May 2023. The experimental design used was Randomized Complete Block Design (RCBD) with 6 treatments and each treatment was replicate 4 times. The treatments are consisted of the application of mixed herbicides IPA glyphosate 486 g/L and methyl metsulfuron 1 g/L at doses of 1 L/ha; 1.5 L/ha; 2 L/ha; 2.5 L/ha; manual weeding; and control (no treatment). The results shows that the mixed herbicide IPA glyphosate 486 g/L and methyl metsulfuron 1 g/L at a dose of 1 L/ha to 2.5 l/ha is effective in controlling weeds in oil palm, such as Paspalum conjugatum, Ottochloa nodosa, Asystasia intrusa, Ageratum conyzoides, Chromolaena odorata, other weeds, and total weeds up to 12 Weeks After Application (WAA).

Pengendalian Hama Terpadu pada Peremajaan Sawit Rakyat di Kecamatan Pangkalan Kuras, Riau

The rapid development of oil palm replanting areas will lead to ecological problems such as plant disturbing organisms. Pest and disease attacks are obstacles farmers face when developing their farms, especially in smallholder oil palm plantations. This study aims to examine the components of cultivation techniques, environmental factors, and human resources that influence the application of IPM on smallholder oil palm replanting land in Pangkalan Kuras District, Pelalawan Regency, Riau Province. The methods used in this study included the purposive determination of 60 respondents, data collection through interviews with farmers, field surveys, and data analysis. The results showed that socio-economic aspects influenced farmers' actions in implementing IPM. Farmer knowledge about pests and diseases of oil palm plants was 36%. Farmers have applied several pest and disease control techniques in oil palm cultivation on replanting land. However, most farmers (60%) are still unfamiliar with the term IPM, need to learn the role of natural enemies in pest control in the field, and lack regular monitoring. Keywords: disease, IPM, palm oil, pest, replanting

Agronomic Suitability for Oil Palm Growing in Uganda

The ever-increasing demand for vegetable oils with its products in Uganda, calls for new areas to be put under oil palm cultivation. A study was conducted to investigate the agronomic suitability of oil palm cultivation in six areas located within a 30 km radius off-shore, on the island and more than 30 km radius off-shore on the mainland. The experiment was superimposed on 45 × 45 m plots in oil palm adaptive trial plantations established in 2008 in Bugiri, Mayuge, Buvuma, Mukono, Kibaale and Masaka districts. The experiment was laid out in a randomized complete block design with three replications. Data on number of oil palm bunches, bunch weight and yield was collected while climatic data (rainfall, temperature, relative humidity and radiation) was acquired from meteorological stations near the experimental locations. Rainfall data analyzed and dry season duration suggested that Mayuge, Masaka, Mukono, Buvuma and Kibaale were moderately favorable for oil palm growing, while temperature and radiation data indicated that all study locations were suitable for oil palm growing. Furthermore, based on relative humidity, Buvuma, Mayuge and Bugiri were suitable for oil palm cultivation but Kibaale, Masaka and Mukono were moderately suitable. Oil palm yield varied significantly (P < 0.05) across locations. The yield was much greater in Mukono (17.7 t/ha/yr) followed by Buvuma (13.8 t/ha/yr) and Kibaale (12.9 t/ha/yr) then Mayuge (10.7 t/ha/yr), Bugiri (10.2 t/ha/yr), and Masaka (10.3 t/ha/yr). The significantly high yield of oil palm observed in Mukono was attributed to the high rainfall received in this location. Based on research findings, Mukono, Masaka, Bugiri, Buvuma, Kibaale and areas within the 30 km radius of Lake Victoria are agronomically suitable for oil palm cultivation.

Inventarisasi Serangga Entomofag yang Berasosiasi pada Bunga Pukul Delapan (Turnera ulmifolia) dan (Turnera subulata) di Perkebunan Kelapa Sawit (Elais guineensis Jacq.) PT. Dendy Marker Indah Lestari, Kabupaten Musi Rawas Utara, Sumatera Selatan

Palm Oil Palm is a potential plantation to be developed in Indonesia. Pests are a limiting factor in oil palm cultivation factories. Pest attacks on oil palm plants can cause growth disturbances and defoliation of up to 100%. This study aims to determine the associated entomophage insects in T. subulata and T. ulmifolia plants. This research is a direct survey in the oil palm plantation of PT. Dendy Maker Indah Lestari, North Musi Rawas Regency, South Sumatra Province from September 2022 to November 2022. The results of the study found 11 entomophage insects associated with T. ulmifolia and T. subulata plants. These eleven insect species consist of 8 species of predatory insects belonging to 5 orders and 6 families there are Coccinella transversalis, Condylostylus sp., Syicanus croceovittatus, Syicanus croceovittatus, Cosmolestes picticeps, Rhynocoris rubricus, Odontomantis planiceps, Mantis religiosa, Citrine forktail and 3 species parasitoid insects belonging to 1 order and 2 families, there are Brachymeria sp., Antocephalus sp., and Aleiodes sp. The most dominant predatory insect species found was C. picticeps with a total of 441 individuals. The most dominant parasitoid insect species found was Brachymeria with a total of 3108 individuals. The conclusion in this study was that more dominant predatory insect species were found associated with flowers than parasitoid insects.