4. Sudradjat_VOL2_2014.cdr Abstract The oil palm ( )s are highlyElaeis guineensis Jacq. ef�cient . It produces �ve to seven timesoil producers more vegetable oil per hectare than soybean, sun�ower, and rapeseed. cThe obje tives of this research were to study the role of organic and N, P, and K fertilizers on growth of immatureone-year-old oil palm on marginal soil in Jonggol. The research was conducted at IPB Cargill Teaching Farm of Oil Palm, Jonggol,(ICTF) Bogor, West Java from March 2013 to March 2014. The experiment was ed factorial experimentarrang in a following a randomized block design with three replications. The �rst factor was organic fertilizer (manure) consist of 0 , 15 and 30 kg pering (O) (O ) (O )1 2 tree per year. The second factor was inorganic fertilizer consist of 0ing (S ); 0.25 kg N + 0.25 kg P O + 0.39 kg0 2 5 K O (S ) 0.50 k N + 0.50 kg P O + 0.78 kg K O (S )2 2 5 21 2and g per tree demonstrated that a. The results pplication of manure up to 30 kg did not affect theper tree per year growth of one year-old oil palm 0.50 k N- . Application of g + 0.50 kg P O + 0.78 kg K O highest2 5 2 per tree gave the result in increasing frond production, stem girth, and leaf nutrient concentration. The results of leaf analysis and plant growth responses suggested that rate ofthe s manure in this studyand inorganic fertilizers applied are not suf�cient to improve young oil palm growth in marginal soil in Jonggol. Keywords: cow ,manure critical nutrient level, inorganic fertilizer, soil fertility, vegetative growth Introduction The oil palm ( ) belongs toElaeis guineensis Jacq. which the Family Arecaceae ef�cient .is a highly oil producer The oil palm produces �ve to seven times more vegetable oil per hectare than soybean, sun�ower, and rapeseed (Basiron and Weng, 2004; Obi and Udoh, 2012). Indonesia is the major oil palm produc in theer world oil palm plantation in Indonesia has rapidly. The increased from four decades ago. The area of oil palm plantation in Indonesia has expanded expon ntiallye from about 80 000 ha in 1965 to 9.8 ha in 2012, million and produce 23.5 t of rude alm ilmillion onnes c p o (Directorate General of Estate Crops, 2013). The demand for edible vegetable and palm oil has increased the increase of per capita consumptiondue to and population growth. The demand of palm oil is expected to double from present consumption of around 120 to 240 by 2050 (Corley, 2009). If oilmillion tonnes palm production does not expand to contribute theto increas of demand, it will result in a shortage of supplye of palm oil. Production can be increased by area expansion and yield intensi�cation in existing plantations. Yield improvement can be achieved by improv crop management. Increase in yield canement of reduce the amount of land expansion for palm oil production. The main issue that will occur in the future in expansion area is shifting the use of agricultural lands of fertile land to marginal lands s. Most of oil palms were planted in poor fertility status (Ng et al., 2011;soil with Obi and Udoh, 2012). Therefore application of organic and inorganic (synthetic) fertilizers are important to supply nutrient n this marginals for the crops grown o soil. M soundaximizing oil productivity of the oil palm through agricultural s providingpractice and balanced nutrition raised oil palm yields (Ng, 2001). Application of inorganic fertilizer provide plant nut ients that can notr be suppl by soil.ied the Nitrogen fertilizer is one of the most expensive nutrient inputs in oil palm production (Amir et al. 2001). Therefore, it is very important to manage fertilizer application and use the nitrogen ef�ciently. Organic fertilizer can improve the physical, chemicalsoil and biological properties such as improving water capacity, aeration, porosity, soil agregation, cation exchange capacity and microorganism activity in the soil (Yang et al., 2004; and , ).Leszczynska Malina 2011 Studies investigating the role of organic residues on young oil palm growth were conducted by Khalid (1999; 2000) in Malaysia. fertilizerOrganic application was In�uence of Manure, Nitrogen, Phosphorus and Potassium Fertilizer Application on Growth of One-year-old Oil Palms on Marginal Soil in Jonggol, Bogor, Indonesia. Sudradjat , Yan Sukmawan , Sugiyanta A B A* A Bogor Agricultural University, Department of Agronomy and Horticulture, Bogor, Indonesia 16680 B Post Graduate Student, Bogor Agricultural University Department of Agronomy and Horticulture, Bogor, Indonesia 16680 Corresponding author; email: * sudradjat_ipb@yahoo.com Journal of Tropical Crop Science Vol. 1 No. , 20142 October www.j-tropical-crops.com 18 effective to increase growth of oil palm seedlings (Uwumarongie-Ilori et al., 2012 )., Ovie et al. 2014 The obje tive of this research was to study the effect ofc manure and single element of N, P, and K fertilizer application youngon growth of one-year-old oil palms on marginal .soil in Jonggol Material nd Methodsa Experimental iteS The research was conducted IPB-Cargill Teachingat Farm located in Jonggol District, West Java, Indonesia ( )6.453144°S, 107.039198°E from March 2013 to March 2014. Soil type in the research area is Ultisols with an altitude 113 m above sea level. The rainy seasonof ± the usually occurs between November and February and t each yearhe dry season between June to September . Average rainfall in the research area was 302.6 mm per month total rainfall from March 2013 to Marchwith a 2014 3 631 mm. Average air temperature was 28.8 Cof , o and average relative humidity was 77.3%. Materials The oil palm Tenera var. Damimas.study used One- year-old plants iwere planted n December 2012 in 9.2 m x 9.2 m x 9.2 m triangular pattern with a population of 136 . kg organic fertilizertrees per hectare Sixty of in the form of decomposed cow manures, 500 g rock phosphate and 500 g dolomite were applied to each planting hole. Experimental esign and reatmentsD T The experiment arrang in awas ed factorial experiment following a randomized block design with three replications. The �rst factor was organic fertilizer (cow manure) consist of 0, 15, and 30 kg per tree per year,ing applied once in March 2013. The second factor was single element S0fertilizers consist of 0ing ( ), 0.25 kg N + 0.25 kg P O + 0.39 kg K O ( ) 0.50 k N + 0.50 kg2 5 2 S1 and g P O + 0.78 kg K O ( ) The2 5 2 S2 per tree. N, P, and K fertilizer treatment applied three times,were i.e. in March, June and December 2013. The soil analysis was conducted on the levels of total nitrogen, available P, exchangable K bulk density, and organic matter content. Scoring was conducted monthly from March 2013 to March 2014 on frond production, stem girth and leaf area hlorophyll and leaf nutrient concentration. Leaf c were measured at 6 and 12 month after treatment (MAT). The youngest fully expanded leaf the top ofon the leaf crown was assigned as number 1, the next down as number 2, and so on (Legros et al., 2009). Leaf area was measured based on a measurement method developed by .Hardon et al. (1969) The effect of treatments were analyzed by ANOVA and further analysed using Duncan Multiple Range Test (DMRT) and considered signi�cant at <0.05.P Results nd Discussiona The chemical and physical properties are presentedsoil in Table 1. Based on the soil criteria for oil palms the soil, Parameter Value Criteria* pH: H2O 5.00 low KCl 4.30 low Organic C (%) 1.83 low Total N (%) 0.17 low C/N 10.76 intermediate Avaible P (ppm) 7.60 very low Ca (me.100 g -1 ) 5.70 intermediate Mg (me.100 g -1 ) 4.74 intermediate K (me.100 g -1 ) 0.20 very low Na (me.100 g -1 ) 0.23 low Cation Exchange Capacity (me. 100 g -1 ) 21.59 intermediate Base Saturation (%) 50.35 intermediate Exchangeable Al (me.100 g -1 ) 3.45 - Exchangeable H (me.100 g -1 ) 1.14 - Texture: Sand (%) 24.65 Silt (%) 49.43 Clay (%) 25.92 loam *Criteria by Indonesian Oil Palm Research Institute. Table 1. hysical and chemical of Jonggol soilP properties Journal of Tropical Crop Science Vol. 1 No. , 20142 October www.j-tropical-crops.com 19In�uence of Manure, Nitrogen, Phosphorus and Potassium Fertilizer.......... in Jonggol ic soilwas acid and low in organic matter. The total N, available P, and exchangable K are low or very- low, soil bulk density is 1.20 g cm thus indicating poor -3 soil fertility. Manure application had no signi�cant effect on the vegetative growth of oil palm from the beginning to the end of the experiment. A ofpplication N, P, and K fertilizer signi�cantly increased onwardsthe growth of oil palm MATat �ve . Response of lowoil palm to fertilization for severalwas months after transplanting, likely due to transplanting shock. It took time for the seedlings to build an effective root system . Application of N,(Goh and Hardter, 2003) P, and K fertilizer gave the resultsat level highestS2 to improve one year-oldthe growth of oil palm onyoung marginal soil in Jonggol. The Effect of Manure and Fertilizer Application on Palm Oil Vegetative Growth and Frond Production Manure application did not signi�cantly affect frond production, N, P, and K fertilizer signi�cantlywhereas increased frond on 5 and 10 MAT (Table 2).production The highest frond production was achieved by application of N, P, and K fertilizer and . N,s at S level1 S2 P, and K fertilizer and S2 increasing fronds at levelS1 production 26.3 and 21.0 % respectively-32.1% -42.7 , , compared control effect of N, P, and Kto . fertilizersThe were only at 5 and 10 ; this may besigni�cant MAT associated with of fertilizer application. pplicationtime A of single component N, P, and K fertilizer weres conducted three times i e in March 2013 (0 ), June, . . MAT 2013 (3 ) and December 2013 (9 ) soMAT MAT , frond production shows a response to N, P, and Ksigni�cant fertilizer at one to two months after application.s F prond roduction is also affected by climatic factors such as rainfall (Figure 1) Water is important for plants. Tabl Thee 2. fects of and N, P, K fertilizer (S) on frond productionef manure application 1 3 5 7 9 10 11 12 0 kg 0.80 1.60 1.82 0.36 2.18 1.44 2.27 2.69 15 kg 0.87 1.73 1.96 0.56 2.41 1.73 2.51 2.93 30 kg 0.76 1.76 2.02 0.36 2.34 1.73 2.40 2.98 S0 0.78 1.62 1.67b 0.33 2.11 1.31b 2.35 2.89 S1 0.73 1.73 2.11a 0.40 2.32 1.73a 2.24 2.80 S2 0.91 1.73 2.02a 0.53 2.50 1.87a 2.58 2.91 Treatment Time (MAT) Frond production (frond.month -1 ) Rates of Manure (kg.tree -1 ) N, P, K fertilizer (S) Note: -MAT = month after treatment; = without ap lication of N, P, K fertilizer-S0 p = ap lication of 0.25 kg N + 0.25 kg P O + 0.39 kg K O-S1 p 2 5 2 = ap lication of 0.50 k N + 0.50 kg P O + 0.78 kg K O-S2 p g 2 5 2 DMRT-Values followed by different letters within a column are signi�cantly different at 95% Figure 1. Effect of N, P, K fertilizer rainfall on frond productionapplication and correlation with (mm) . Journal of Tropical Crop Science Vol. 1 No. , 20142 October www.j-tropical-crops.com 20 Sudradjat, Yan Sukmawan, Sugiyanta as raw material for photosynthesis, part of the plant cell, and solvent Frond production in afor the nutrients. month is in�uenced by rainfall one to two months earlier. F prond roduction ranged from 1.5 to 3 per months under suf�cient rainfall (>100 mm per month) and can dramatically 0.5 per months or lessdecrease underto lower rainfall (<100 mm per month). However, based on observations in the �eld the plants still formed a few spears under low rainfall. When rainfall is suf�cient the spear open sooner so that production increasess frond to 2.5 per (9 ). The fewermonth MAT frond, Table 2 production during dry season is probably related to the poor nutrients absorption by the plants. Water plays an important role in dissolving nutrients that can be absorbed by plant roots in the soil so that water shortages will nutrient uptake result indisrupt , which will a stunted plant growth. An increasing rate of manure application up to 30 kg per plant per year tends to result in increasegreatest of stem girth S2 treatment resulted in t highest(Table 3). he growth girth, i.e. 57.09 cm, but not signi�cantlyof stem different with 53.20 cm. The increaseS1 treatment, i.e. in werestem girth due to S1 and S2 treatment 11.9 % and 20.1% respectively compared control at 12, , to DAT. Palm trunks serve as support structures of leaves, �owers, and fruit; vascular system transportthat s nutrients, water and ; and as an organassimilate accumulation of nutrients (Corley and Tinker 2003)., Oil palm trunks represent approximately 50% of the total above-ground biomass when the plants reach the age of 10 years (Corley and Tinker 2003). The large girth, stem will support high fruit production . Thein the future increase girth is in�uenced by the availability ofin stem N, P, and K collectively (Corley and Tinker, 2003). N is a major constituent amino acids, amides,itrogen of proteins, and nucleotides role in, and plays a signi�cant the formation of chlorophyll and increase vegetative growth (Ra hman et al., 2008). Phosphorus plays rolec as molecular component of the energy transferor i.e. ATP ADP NAD and NADPH which energy-rich, , are compound that controls various reactions in plants such as photosynthesis, respiration, protein synthesis and amino acids, and nutrient transport (Booromand and Grough 2012) Potassium plays role as an enzyme, . activator, maintaining osmotic potential and water uptake, photosynthesis, and translocationassimilate from to sinkleaf (Taiz and Zeiger, 2010). Application of manure and fertilizer did notN, P, K signi�cantly increase leaf area (Table ). Leaf area is3 one of the important variables for the growth of palm oil. L deaf area etermines sunlight interception that affect the rate of photosynthesis (Hardon et al. 1969). The, wider the leaf area, the higher the rate of photosynthesis is due to an increasing of the of leavesportion that capture sunlight. Even though the effects were not signi�cant, application of manure increased bulk density and soil C, N, P and K levels . Similar results were reported by(Table 4) Uwumarongie-Ilori et al. (2012). Application of organic fertilizer is bene�cial for long-term production thedue to slow release nature of the nutrients (Ermadani and Muzar, 2011). The Effect of Manure and Fertilizer Application on Leaf Stomatal Density, and Leaf N, P and K content Manure and N, P, and K fertilizer application had no effect on leaf stomatal density (Table ). Leaf stomatal5 density ranges from 198-211 mm . For comparison, the -2 Table 3. Effects of and N, P, K fertilizer (S) on stem girth and leaf areamanure application 0 4 8 12 0 4 8 12 15 kg 23.79 30.02 39.61 53.13 0.32 0.86 0.71 1.29 30 kg 23.43 29.62 41.81 55.98 0.32 0.81 0.67 1.21 S0 23.86 28.67 36.20b 47.53b 0.32 0.74 0.70 1.09 S1 23.71 29.63 40.52ab 53.20ab 0.34 0.83 0.63 1.21 S2 23.21 30.51 41.93a 57.09a 0.33 0.87 0.66 1.29 Time (MAT) Stem girth (cm) Leaf area (m 2 ) Rates of Manure Application (kg.tree -1 ) N, P, K fertilizer (S) Treatment Note: MAT = month after treatment;- = without aplication of N, P, K fertilizer-S0 = ap lication of 0.25 kg N + 0.25 kg P O + 0.39 kg K O-S1 p 2 5 2 = ap lication of 0.50 k N + 0.50 kg P O + 0.78 kg K O-S2 p g 2 5 2 DMRT-Values followed by different letters within a column are signi�cantly different at 95% Journal of Tropical Crop Science Vol. 1 No. , 20142 October www.j-tropical-crops.com 21In�uence of Manure, Nitrogen, Phosphorus and Potassium Fertilizer.......... average leaf stomatal density was 146 mm in Nigeria -2 and 175 mm in Malaysia (Corley and Tinker 2003) -2 , . A mverage leaf stomatal density in this study was 201 m -2 at 6 and 208 m at 12 .MAT m MAT -2 Manure and N, P, and K fertilizer did not signi�cantly affect leaf chlorophyll content (Table ). Chlorophyll5 plays an important role in photosynthesis. Chlorophyll Tabel 4. Effects of onmanure application soil bulk density, soil organic C, soil total N, P and K Rate of Manure Application (kg.tree -1 ) Bulk Density (g cm -3 ) Organic C (%) Total N (%) Total P (ppm) Total K (ppm) 0 1.05 1.12 0.10 114.52 54.00 15 1.02 1.15 0.10 125.97 60.60 30 0.98 1.28 0.11 145.98 75.00 Table 5. Effects of and N, P, K fertilizer (S) on stomata density and chlorophyll contentmanure application leaf l 6 12 6 12 0 199.08 208.90 0.032 0.042 15 206.07 207.20 0.036 0.042 30 198.52 208.62 0.035 0.042 S0 203.61 206.92 0.033 0.042 S1 198.14 206.92 0.034 0.041 S2 201.91 210.88 0.037 0.043 N, P, K single fertilizer (S) Treatment Time (MAT) Stomatal density (mm -2 ) Chlorophyll content (mg.cm -2 ) Manure Manure (kg.tree -1 ) Note: MAT = month after treatment;- = without ap lication of N, P, K fertilizer-S0 p = ap lication of 0.25 kg N + 0.25 kg P O + 0.39 kg K O-S1 p 2 5 2 = ap lication of 0.50 k N + 0.50 kg P O + 0.78 kg K O-S2 p g 2 5 2 Note: MAT = month after treatment;- = without ap lication of N, P, K fertilizer-S0 p = ap lication of 0.25 kg N + 0.25 kg P O + 0.39 kg K O-S1 p 2 5 2 = ap lication of 0.50 k N + 0.50 kg P O + 0.78 kg K O-S2 p g 2 5 2 DMRT-Values followed by different letters within a column are signi�cantly different at 95% Table 6. Effects of and N, P, K fertilizer (S) on leaf nutrient concentrationmanure application Journal of Tropical Crop Science Vol. 1 No. , 20142 October www.j-tropical-crops.com Treatment Manure (kg.tree ) -1 0 15 30 N, P, K single fertilizer (S) S0 S1 S2 N (%) 2.64 2.56 2.67 2.35 2.73 2.79 P (%) 0.20 0.20 0.20 0.19 0.20 0.20 K (%) 1.11 1.17 1.31 1.09b 1.20ab 1.31a N (%) 2.14 2.12 2.26 2.03b 2.15b 2.33a P (%) 0.19 0.19 0.20 0.19 0.20 0.20 K (%) 0.84 0.88 0.89 0.80b 0.86b 0.95a Time (MAT) 126 22 Sudradjat, Yan Sukmawan, Sugiyanta absorbs light and pass it to the reaction center of photosystem (Karacan 2006). Chlorophyll content in, this study ranged from 0 032 0 043 mg.cm .. to . -2 Leaf analysis showed that manure application had no signi�cant effect on N, P and K N,leaf content (Table 6). P, and K fertilizer only affected the N at 12 , andleaf MAT leaf K at 6 and 12 but did not affect leaf P contentsMAT, (Table 6). pplication N, P, and K fertilizerA of at levelS2 resulted in the the increased of leafhighest N and K contents oil. Critical nutrient levels in the leaves of young palm 2.75%s according to Ochs and Olivin (1977) are for N, 0 16% for P and 1 25% for K. reatment. . S2 t resulted in contentsleaf N and K above the critical nutrients levels n 6 . Leaf P in this studyo MAT content was not signi�cantly affected by manure and inorganic fertilizers treatment and the level is classi�ed as suf�cient according to Ochs and Olivin (1977). The results of leaf analysis and plant growth responses suggested that rate of organic and inorganic fertilizers applied are notin this study suf�cient to improve young oil palm growth in marginal soil. High rate of fertilizer application is usually recommended for marginal soils and soil with low fertility ( , ,Vanlauwe et al. 2001; Ng et al. 2011). Conclusions Application of up to 30 kg didmanure per tree per year not affect the growth of one year-old oil palm- . Application of g0.50 k N + 0.50 kg P O + 0.78 kg K O2 5 2 per tree highestgave the increase in frond production, stem girth, Application ofand leaf nutrient concentration. manure, N, P, and K fertilizer in this study did not affect leaf stomatal density, leaf chlorophyll and leaf N, P, and K content. References Amir, H.G., Shamsuddin, Z.H., Halimi, M.S., Ramlan, M.F., and Marziah, M. (2001). Effects of Azospirillum inoculation on N �xation and growth2 of oil palm plantlets at nursery stage. Journal of Oil Palm Research , 42-49.13 Basiron Y , Weng . 2004 . The oil palm and its, . , C. K ( ) sustainability. 1-Journal of Oil Palm Research 16, 10. Boroomand, N., Grouh, M. S. H. (2012). 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