JUATIKA
JURNAL AGRONOMI TANAMAN TROPIKA
VOL.
6 NO.
1 January 2024 DOI :https://doi.
org/10.
36378/juatika.
eissn 2656-1727 pissn 2684-785X Hal : 139 Ae 148 Effect of NBPT-DCD (Urease and Nitrification Inhibito.
on Nitrogen Loss.
N Uptake and Oil Palm Yields (Elaeis guineensis Jacq.
) bn Typic Dystrudepts Soil Khairuddin1.
Wawan2*.
Besri Nasrul2.
Feri Seftiadi1.
Haryanto1.
Achmad Fathoni1.
Nizam Tambusai1 Research & Development Department First Resources.
Jln.
Kubang Jaya.
Siak Hulu.
Kampar Regency.
Pekanbaru.
Riau 28293 Indonesia Universitas Riau.
Jln.
Kampus Bina Widya Km 12,5 Simpang Baru Pekanbaru.
Riau 28293 Ae Indonesia *Email : awanwawan0215@gmail.
ABSTRACT
Incorporating N-.
-buty.
thiophosphoric triamide (NBPT) as a urease inhibitor and Dicyandiamide (DCD) as a nitrification inhibitor can enhance the efficiency of nitrogen (N) The main aim of the study was to evaluate the impact of urease and nitrification inhibitors (NBPT and DCD) on N loss in urea fertilizer.
N absorption, and oil palm (Elaeis guineensis Jacq.
) yield.
Researchers conducted the field trial using a single-factor, completely randomized design (CRD) with three replications.
The experimental treatments included nitrogen (N) fertilization with 5 different levels.
The levels were: 100% urea .
75 kg/plant/year:
50 kg/plant in rotation 1 and 1.
25 kg/plant in rotation .
(N.
, 80% urea NBPT-DCD .
kg/plant/year: 1.
20 kg/plant in rotation 1 and 1.
0 kg/plant in rotation .
(N.
, 60% urea NBPTDCD .
65 kg/plant/year: 0.
90 kg/plant in rotation 1 and 0.
75 kg/plant in rotation .
(N.
Urea dosage of 80% .
20 kg/year: 1.
20 kg/plant in rotation 1 and 1.
00 kg/plant in rotation .
(N.
, and Urea dosage of 60% .
65 kg/plant/year: 0.
90 kg/plant in rotation 1 and 0.
75 kg/plant in rotation .
(N.
The findings revealed that the application of Urea in combination with NBPTDCD .
nhibitors of urease and nitrificatio.
led to a reduction in N loss by 30.
48% and an increase in N absorption compared to Urea without NBPT-DCD.
Oil palm trees grew on Typic Dystrudept soil.
The plants received 2.
20 kg of urea treatment per plant.
The researchers combined Urea with NBPT-DCD.
These trees had better outcomes than others.
They had less N volatilization and better N absorption.
They also had higher fresh fruit bunch productivity.
The others received N fertilization but not NBPT-DCD.
Keywords: N fertilizer (Ure.
NBPT-DCD, urease inhibitor, nitrification inhibitor, oil palm.
Copyright A 2024.
The authors.
This is an open access article under the CC BY license .
ttps://creativecommons.
org/licenses/by/4.
Khairuddin et.
INTRODUCTION
Oil palm (Elaeis guineensis Jacq.
is a highly productive plantation commodity for vegetable oil production, surpassing other vegetable oil-producing Consequently, it has been extensively cultivated on a large scale.
Indonesia holds the distinction of being the largest oil palm grower and crude palm oil (CPO) producer globally.
2018, the country had a planted area of 3 million hectares, yielding a CPO production of 42.
9 million tons (Direktorat Jenderal Perkebunan 2.
As per PASPI Indonesia's CPO production has experienced rapid growth, positioning it as the world's leading CPO In 2015.
Indonesia accounted for approximately 53% of global CPO production, with Malaysia following at The export value of CPO and its products rose, reaching USD 15.
4 billion in 2008 and USD 21.
6 billion in 2011.
Then, it fell to USD 18.
6 billion in 2015 due to lower CPO prices.
As a result, the palm oil industry greatly adds to the country's foreign exchange earnings.
They come from the non-oil and gas To achieve maximum oil palm productivity, it is crucial to take into account all the characteristics and critical factors involved in the cultivation process.
According to Jannah et al.
, by technology, we can significantly enhance oil palm production and bring it closer to its full potential.
However, it is important to note that the productivity of oil palm plantations currently varies greatly.
This diversity primarily stems from the characteristics across these plantations.
Therefore, it becomes essential to have objective information about the fertility of each soil type in order to provide accurate agronomic recommendations.
Oil palm plantations in Indonesia are predominantly grown on acidic mineral soil.
The country has a vast expanse of 107.
36 million hectares of Juatika Vol.
6 No.
such land (BBSDPL, 2.
, with one example being the Typic Dystrudepts These soils are characterized by their low fertility, which is evident in their acidic to slightly acidic soil reactions .
H The content of organic carbon, cation exchange capacity (CEC), and (A.
significantly, ranging from very low to very high.
Available nutrients, such as phosphorus (P), are generally low to very low, while potassium (KB) levels are very To enhance the agricultural potential of Typic Dystrudepts soils, it is crucial to improve their chemical properties through the application of organic and inorganic fertilizers, as well as lime, to adjust the pH and reduce Al saturation (Busyra et , 2.
Fertilization plays a crucial role in determining the productivity of oil palm.
fact, more than half of the production costs in oil palm cultivation are allocated to fertilization activities, as stated by Hakim in 2007.
The currently developed oil palm hybrids have shown positive responses to fertilization, as highlighted by Nurjaya in 2009.
Fertilizer holds immense significance as a limiting factor that influences the growth of oil palm plants, as mentioned by Corley and Tinker in 2016.
However, the global price hike and reduced availability of fertilizer have posed challenges.
Therefore, it is essential to enhance fertilizer efficiency and explore alternative fertilizers with high efficacy.
For a long time, the application of inorganic fertilizers has been a key method to boost productivity and replenish soil nutrients in oil palm crops, as emphasized by Soh et al.
Nevertheless, improper fertilization practices can lead to inefficiencies in oil palm cultivation, especially with the rising fertilizer prices.
Nitrogen represents a crucial macronutrient for oil palm cultivation.
Nevertheless, its mobility in the soil makes it susceptible to loss through leaching, volatilization, and binding into unavailable compounds for plant uptake.
Khairuddin et.
The primary mechanisms responsible for nitrogen loss in soil include denitrification, volatilization, decomposition, leaching, and plant absorption (Sanchez, 1.
According to Hardjowigeno .
, strategies aimed at delaying nitrogen release from urea fertilizer can help mitigate environmental pollution, as nitrate contamination from nitrogen entering water bodies serves as a significant source of water pollution.
Inorganic nitrogen forms such as nitrate, nitrite, and ammonia serve as key indicators of water pollution.
Nitrification poses a threat to water quality by converting NH4 into soluble NO3-, leading to elevated nitrate levels in groundwater that can stimulate the growth of microbes, algae, plankton, water hyacinth, and other aquatic plants through water fertilization by nitrates.
Urea (CO[NH.
is the most commonly utilized nitrogen (N) fertilizer in the cultivation of oil palm.
However, its effectiveness is compromised due to its hygroscopic and volatile nature, as well as its rapid decomposition.
According to Abdul Rachman and Pahim .
, the consumption of domestic Urea has increased significantly over the past three decades, rising from 372,260 tons in 1969 to 4,288,648 tons in 1998, marking a tenfold increase.
The World Bank has reported that Indonesia's fertilizer usage surpasses that of other Asian countries.
In 2014.
Hidayani's research findings revealed that in West Sumatra alone, on an area spanning 381,754 hectares, a staggering 163,772,466 kg of N fertilizer was applied to oil palm plants.
However, the actual amount of N fertilizer absorbed by the plants was only 73,697,609.
70 kg, resulting in a wastage of 90,074,856.
These figures indicate that the N uptake efficiency stands at a mere 45%.
The rapid loss of NH3 in urea fertilization applications is primarily due to the quick release of NH3 from Urea after application, which does not correspond proportionally to the rate of uptake by the This rapid release of NH3 from Juatika Vol.
6 No.
Urea is attributed to its hygroscopic nature, leading to the immediate activation of urease upon dissolution in The heightened urease activity expedites the release of NH4 from Urea, which then reacts with OH- at pHOu7 to form H2O and NH3, resulting in the easy loss of NH3 through volatilization.
To mitigate NH3 loss through volatilization, inhibiting urease activity can be effective in slowing down the release of NH4 from Urea, allowing plants to absorb more N in the form of NH4 .
Moreover, the gradual release of NH4 from Urea leads to a lesser conversion to NH3, thereby reducing the rate of N loss in the form of NH3.
This controlled release of NH4 from Urea has the potential to enhance the efficiency of N uptake by oil palm plants when Urea is utilized as a fertilizer.
In addition to inhibiting urease activity, the suppression of nitrogen loss can also be achieved by inhibiting The utilization of nitrification inhibitors can effectively decrease the conversion of ammonium (NH4 ) to nitrate (NO3-) and the production of N2O denitrification processes.
According to Nainggolan et al.
, the application of nitrogen fertilizer to the soil can enhance the nitrification reaction by reducing soil pH and promoting the formation of nitrate.
The activity of nitrosamine and nitrobacteria, which are obligate autotrophic bacteria, leads to an increase in nitrate levels in the soil during the nitrification process when ammonium nitrate is converted.
The concentration of nitrate in the soil is closely associated with the ammonium concentration.
As the ammonium concentration increases, the nitrate concentration in the soil tends to rise as well.
The process of nitrate formation, known as nitrification, is carried out by Nitrosomonas, which converts ammonium to nitrite, and nitrobacteria, which convert nitrite to Khairuddin et.
There are multiple approaches to enhance the efficiency of fertilizers, and these include improving the techniques of fertilizer application, enhancing the physical and chemical characteristics of fertilizers, altering the shape and size of fertilizers, and regulating nutrient levels to match the specific requirements of plants.
By implementing these methods, the aim is to ensure that plants can utilize the nutrients provided by fertilizers most One strategy to specifically enhance the efficiency of nitrogen (N) fertilization involves improving the chemical properties of urea fertilizer.
This can be achieved by coating urea with N.
-buty.
(NBPT/C4H14N3PS), which acts as a urease inhibitor in urea fertilizer (CO[NH.
Additionally, dicyandiamide (DCD/C2H4N.
commonly used as nitrification inhibitors in urea fertilizer (CO[NH.
to enhance their effectiveness further.
The utilization of these two substances helps to prevent nitrogen loss in the soil.
However, it is important to conduct tests to determine the efficacy of these materials in inhibiting urease activity and nitrification.
Hence, it is imperative to conduct a research study to evaluate the efficacy of NBPT and DCD in suppressing urease activity and N nitrification in oil palm The significant effectiveness of NBPT and DCD in inhibiting urease and nitrification processes can lead to a decrease in the loss of N fertilizer in oil palm cultivation.
From an economic perspective, this could result in potential cost savings due to the reduced application of N fertilizer.
Moreover, from an ecological standpoint, the utilization of urease and nitrification inhibitors has the potential to mitigate the risk of N contamination in both soil and the The risk of N contamination is particularly high in oil palm cultivation compared to other crops, given the high N requirements per plant and the extensive cultivation area.
This risk is exacerbated when the efficiency of N Juatika Vol.
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uptake from applied fertilizers is low.
Incorporating NBPT and DCD into urea application could not only lower fertilizer expenses related to N fertilizers but also ensure the long-term viability of oil palm plantations and promote environmental sustainability by reducing N loss rates.
MATERIAL AND METHODS
The study was carried out between January 2021 and December 2022 at an oil palm plantation situated in Kubang Jaya Village.
Siak Hulu District.
Kampar Regency.
Riau Province.
The precise geographical coordinates of the site are 0.
4219958 latitude and The condition in the research area is classified as Typic Dystrudept.
The temperature at the research location ranges from 25 to 30 degrees Celsius, while the annual rainfall varies from 2,000 to 2,500 mm.
The field trial was conducted using a single-factor, completely randomized design (CRD) with three replications.
The experiment focused on nitrogen (N) fertilization, which included 5 different Urea .
kg/plant/year: 1.
50 kg/plant in rotation 1 25 kg/plant in rotation .
(N.
, 80% urea NBPT-DCD .
20 kg/plant/year:
20 kg/plant in rotation 1 and 1.
kg/plant in rotation .
(N.
, 60% urea NBPT-DCD .
65 kg/plant/year: 0.
kg/plant in rotation 1 and 0.
75 kg/plant in rotation .
(N.
Urea dose 80% .
kg/year: 1.
20 kg/plant in rotation 1 and 00 kg/plant in rotation .
(N.
, and Urea dose 60% .
65 kg/plant/year: 0.
kg/plant in rotation 1 and 0.
75 kg/plant in rotation .
(N.
Additionally.
Rock Phosphate fertilizer .
% P2O.
kg/plant.
KCl fertilizer .
% K2O) at 3.
kg/plant.
Kiserite fertilizer .
% MgO) at 75 kg/plant, and HGFB fertilizer .
% B2O.
10 kg/plant were also The fertilizers were spread on the oil palm plant disk (Ring Placemen.
The experiment comprised 5 treatments with 3 replications, resulting in Khairuddin et.
Juatika Vol.
6 No.
a total of 15 experimental units.
Each Leaf sampling is done by experimental unit consisted of 36 plants, taking the leaves on the 17th midrib, and thus requiring a total of 540 oil palm trees then the leaves are taken from the flat for the study.
endpoint in the middle position of the The parameters of environmental Sampling was done 6 times observation are climatic observations to during the experiment, namely months 3, determine the environmental conditions 6, 12, 15, 18 and 24.
Observation of at the research site, namely rainfall, fresh fruit bunch (FFB) production.
sunshine, humidity, and temperature of Production observations were made for the research site.
Other observation every harvest rotation, starting from the parameters are: .
observation of beginning of the experiment, including evaporation of N applied to the oil palm the weight of fresh fruit bunches per disk.
NH3 loss analysis was carried out bunch .
, per stand .
, and hectare using the foam method (Cantarella et al.
Observations were made for 24 2.
, carried out in the second and months .
fourth weeks after the application of N The collected data was subsequently Each treatment per plot installed subjected to Analysis of Variance one tube .
to capture NH3 lost (ANOVA) with a significance level () of through evaporation, and the NH3 came 5%.
If the ANOVA results indicate that from the N fertilizer applied per oil palm the obtained F-value is greater than the Therefore, overall, this study will critical F-value, it signifies the presence use 15 units of cylindrical tubes .
to of significant differences between the capture vaporized NH3.
Analysis of N treatments.
In such cases, the analysis in plant tissues .
The plant tissue proceeds with the application of the analysis carried out is the analysis of N Duncan Multiple Range Test.
levels in the leaves of oil palm plants.
This analysis was conducted in the RESULT AND DISCUSSION.
Table 1.
Treatment of Various Doses of N Fertilization and Combination with NBPTDCD in Oil Palm Crops.
Treatment Code Fertilizing Method Urea 2.
75 kg/plant Ring Placement Urea NBPT-DCD 2.
20 kg/ plant Ring Placement Urea NBPT-DCD 1.
65 kg/ plant Ring Placement Urea 2.
20 kg/ plant Ring Placement Urea 1.
65 kg/ plant Ring Placement Environmental Conditions of the Research Area.
The average rainfall recorded in the environmental observations is 2,694.
5 mm, while the average temperature is 26.
91AC.
These rainfall and temperature conditions align with the optimal growth requirements for oil palm According to Pahan .
, oil palm thrives in regions with an annual rainfall of at least 2000 mm, which remains consistent throughout the year, and where the dry months have a rainfall of less than 100 mm and do not exceed three months.
The ideal temperature range for oil palm cultivation is between 29AC and 33AC during the day and 22AC to 24AC at night.
Furthermore.
Sunarko .
highlights the correlation between rainfall, duration of sunshine, and variation in palm oil production.
Extended periods of consecutive dry months can adversely impact flower production, including both the quantity and sex ratio, for the subsequent two years.
Khairuddin et.
Juatika Vol.
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In relation to humidity, it can be that lack the NBPT-DCD coating.
stated that the mean humidity at the Specifically, research location aligns with the ideal percentage of urea volatilization between humidity range for oil palm plants, which NBPT-coated and non-coated fertilizers is approximately 81.
The optimal at the same dosage, there is a difference humidity for oil palm plants falls within the 33% between N1 .
03%) and N3 range of 80-90 degrees, accompanied by .
36%) and a difference of 37.
a wind speed of 5-6 km/hour, which between N2 .
07%) and N4 .
55%).
facilitates pollination (Kiswanto et al.
The application of regular urea fertilizer The duration of sunlight is solely resulted in higher rates of evaporation measured between 08:00 and 16:00 at the weather stations managed by BMKG.
significantly different from the application Consequently, if the area receives of urease fertilizer with an inhibitor at the sunlight for 8 hours, the duration of sun same dosage.
Furthermore, the results exposure amounts to 100%.
The average also indicate that as the fertilizer dosage solar irradiation recorded at the study site increases, the amount of evaporated and 58%, indicating an irradiation time lost nitrogen from the fertilizer also of approximately 4.
05 hours per day.
This increases, and this difference is indicates that during the study period, the statistically significant.
sunlight was not optimal for oil palm The findings of this investigation plants, which typically require 5-7 hours align with the study conducted by Riyadi of sunlight per day (Kiswanto et al.
et al.
in 2020, which demonstrated that the application of NBPT treatment to N Loss on Urea Fertilizer.
Urea can result in a 30-50% reduction in Nitrogen availability in the soil ammonia loss compared to untreated plays a crucial role in agricultural Urea.
Furthermore, research by Bastos et production and tillage systems, given that in 2015 indicated that urease inhibitors plants have a higher demand for this have the potential to decrease N loss nutrient compared to others.
Moreover, levels by approximately 21-43% when nitrogen can be depleted from agricultural compared to fertilizers lacking urease ecosystems through a variety of means, inhibitors.
Moreover.
Roberts et al.
proposed that nitrification inhibitors are agricultural activities.
substances that impede or slow down the The findings presented in Table 2 transformation of ammonium to nitrate, demonstrate that the inclusion of urease influencing the activity of Nitrosomonas and nitrification inhibitors in urea bacteria and offering possibilities for fertilizers can lead to a substantial reduction in volatilization and nitrogen denitrification losses.
loss compared to standard urea fertilizers Table 2.
NH3 Volatilization of Urea under Various Doses of N Fertilization and Combination with NBPT-DCD in Oil Palm Crops Treatm
Days 1-7
Days 8-14
Days 1-14
N volatilization in Urea
(%)
1,090.
17 A 171.
10 A 116.
42 A 100.
70 A 50.
06 bc 10 A 86.
40 A 57.
83 A 180.
80 A 38.
10 A 7.
30 A 16.
1,169.
57A121.
93 A 294.
22 A 72.
1,034.
8 A 47.
74 bc 40 A 102.
96 A 2.
03 A 7.
07 A 2.
36 A 1.
55 A 3.
Total NH3 Evaporation of N Fertilizer Day 1-7 .
Note: Numbers followed by the same letter in the same column indicate results that are not significantly different based on DMRT at = 5%.
Khairuddin et.
Juatika Vol.
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Plant Tissue Analysis Table 3.
N Levels in Leaves of Oil Palm Plants at 3-24 Months of N Fertilizer Experiments in Treatments with Various N Fertilization Doses and Combinations with NBPT-DCD on Oil Palm Plants N Levels in Leaves (%) Treatment
3 BSP
6 BSP
12 BSP
18 BSP
24 BSP
Mean 61 A 0.
82 A 0.
80 A 0.
76 A 0.
69 A 0.
37 A 0.
46 A 0.
42 A 0.
34 A 0.
35 A 0.
52 A 0.
63 A 0.
56 A 0.
68 A 0.
62 A 0.
87 A 0.
75 A 0.
79 A 0.
76 A 0.
29 A 0.
25 A 0.
68 A 0.
64 A 0.
54 A 0.
53 A 0.
55 A 0.
49 A 0.
42 A 0.
43 A 0.
Note: Numbers followed by the same letter in the same column indicate results that are not significantly different based on DMRT at = 5%.
Based on the examination of leaf N levels in oil palm plants (Table .
, it is evident that N fertilization, with or without urease and nitrification inhibitors, does not have a significant impact on leaf N levels in oil palm plants at 3, 6, and 12 months post-N fertilization.
Varied N fertilizer doses resulted in fluctuations in leaf N levels but did not exhibit statistically significant variances.
Notably, the average results at 24 months displayed significant distinctions among The data indicates that the highest leaf N content was observed in the urea NBPT-DCD treatment with a fertilizer dose of 2.
20 kg/tree/year, which was notably different from the same dose NBPT-DCD.
Furthermore, the average outcomes revealed that the N treatment utilizing NBPT-DCD exhibited a higher N nutrient value compared to treatments without NBPT-DCD at equivalent doses.
Oil palm plants fix nitrogen in the forms of NH4 and NO3, derived from nitrogencontaining fertilizers and soil organic Leiwakabessy .
highlighted that the quantity of these ions is contingent upon the fertilizer dosage administered and the rate of organic matter decomposition in the soil.
The nitrogen released from soil organic matter is influenced by the equilibrium between factors affecting the mineralization and immobilization of elemental nitrogen, as well as its loss from the soil layers.
Bonner and Vanner .
proposed that light plays a crucial role in the nitrogen reduction process within the amino acid Nitrogen is intricately linked photosynthesis, where proteins generate ATP converting organic nitrogen for the breakdown of accumulated nitrogen.
Production Results of Fresh Fruit Bunches (TBS) Khairuddin et.
Juatika Vol.
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Table 4.
Production of FFB (Fresh Fruit Bunche.
N Fertilizer Trial on Various N Fertilizer Doses and Combinations with NBPT-DCD on Oil Palm Plants.
Yield 2021
Treatm
Yield 2022
FFB
(Ton/Ha/Y.
Total Kernel /Pkk BJR (K.
FFB (Ton/Ha/Y.
Total Kernel/Pkk 48 A 23 A 12 A 67 A 19 A 11 A 0.
67 A 0.
72 A 0.
76 A 0.
05 A 1.
84 A 1.
71 A 1.
04 A 1.
79 A 1.
85 A 0.
25 A 0.
95 A 0.
09 A 1.
98 A 2.
98 A 0.
79 A 0.
03 A 1.
29 A 0.
67 A 0.
BJR (K.
21 A 0.
84 A 0.
25 A 1.
99 A 1.
69 A 0.
Note: Numbers followed by the same letter in the same column indicate results that are not significantly different based on DMRT at = 5%.
The productivity of oil palm plants is determined by a variety of factors, genetic characteristics, and breeding Environmental factors, such as rainfall, soil quality, and topography, as well as biotic factors like pests and weeds, play a crucial role in influencing oil palm productivity.
Genetic factors, such as the selection of seeds and the age of the plant, also contribute to Additionally, agricultural techniques, including fertilization, soil and water management, weed and pest control, and overall plant maintenance, are important factors that impact oil palm These factors interconnect and mutually influence each other (Pahan Corley .
explains that as the oil palm plant ages, the weight of the bunches it produces increases.
Initially, at the age of 3 years, the average bunch weight is approximately 4 kg per bunch.
This weight continues to rise, reaching 25 kg per bunch when the plant is 15 years old or older.
The author further notes that oil palm productivity experiences a rapid growth phase, peaking between 8 and 12 years of age.
Subsequently, productivity gradually declines with increasing plant age, eventually becoming uneconomical after 25 years.
Well-managed oil palm plantations in Indonesia and Malaysia can achieve a maximum yield of fresh fruit bunches ranging from 24 to 32 tons per hectare per year.
The research plantation contains a range of oil palm plants, specifically the Damimas variety.
In the experimental plots, the DxP (Damima.
variety exhibited an average bunch weight of 1415 kg and an average fresh fruit bunches (FFB) of 29-32 tons/ha/year.
Data presented in Table 4 includes an analysis of variance of production parameters tons/ha, baskets/stocks, and average basket weight (BJR).
Results from observations in 2022 .
-24 month.
indicated that N fertilization treatment, with or without the use of urease and nitrification inhibitors, did not have a significant impact on all However, a comparison between urea dose treatments coated with NBPT-DCD (N1 and N.
and those not coated with NBPT-DCD (N3 and N.
revealed that ton/ha and number of baskets/stalk were higher in the former group at the same dose.
The responsiveness in terms of yield has not yielded significant results.
This result could be due to the fact that the previous experimental area had a history of good guidelines and routine practices.
As a result, it requires a longer time to observe the effects of the treatment given.
This extended timeframe is because of the various stages involved in the growth and Khairuddin et.
development of the plant.
For example, the formation of Primordia takes around 36 months before harvest, while sex determination occurs approximately 24 months before harvest.
Additionally, the period from flower blooming .
to fruit ripening lasts about 6 months.
Analysis of the production trend shows that the N1 treatment demonstrates higher FFB .
ons/ha/yea.
and a greater number of baskets/staples compared to the other treatments.
CONCLUSION
Using Urea in conjunction with NBPT-DCD, which acts as a urease and nitrification inhibitor, significantly reduces N loss by 30.
48% compared to using Urea alone.
Furthermore, the utilization of Urea combined with NBPTDCD has demonstrated the ability to enhance the absorption of N nutrients in Notably, when oil palm plants cultivated on Typic Dystrudept soil were treated with Urea at a rate of 2.
kg/plant in combination with NBPT-DCD, they exhibited the most favorable outcomes in terms of reducing N volatilization, increasing N uptake, and ultimately yielding higher fresh fruit bunch productivity, surpassing the results observed in plants that solely received N fertilization without NBPT-DCD.
REFERENCE