Optimasi Dosis Pupuk Nitrogen dan Fosfor pada Bibit Kelapa Sawit (Elaeis Guineensis Jacq. ) di Pembibitan Utama

The total area of oil palm plantation has grown rapidly in Indonesia since the last three decades. Oil palm extensification and replanting need high quality seedlings. Accurate rate of nitrogen and phosphor fertilizer are key factors to obtain high quality seedlings. The objective of this experiment was to determine the optimum rate of nitrogen and phosphorus fertilizers for oil palm seedling (Elaeis guineensis Jacq.) in main nursery and to obtain seedlings ready for field planting. This experiment was carried out at IPB Experimental Station, Cikabayan Dramaga, Bogor, from November 2011 to May 2012. The experiment was arranged in a factorial randomized block design with three replications. The first factor was N i.e. 0, 8.51, 17.02, and 34.04 g N plant-1 and the second was P i.e. 0, 2.28, 4.56, and 9.12 g P plant-1. The result of the experiment showed that vegetative growth increased with fertilizer application. The height of plant were affected by interaction between N and P significantly. The total leave number and stem diameter increased quadratically with fertilizer rate of N and were linearly increased with application of P. Application of N fertilizer influenced the chlorophyl content only at 5 months after planting, and did not significantly affect the stomatal density. The result of leaf analysis showed that nitrogen and phosphor content respectively were 3.43% and 0.28%, where both of them were above the critical level. The optimum rate of N for oil palm seedling during six months at the main nursery was 20.06 g plant-1, whereas P was 4.24 g plant-1

Pengaruh Penggunaan Pupuk Hayati Terhadap Pertumbuhan Tanaman Belum Menghasllkan (Tbm I) Kopi Robusta (Coffea Canephora Pierre Ex Froehner)

This experiment was aimed to study the effect of biofertilizer on growth of young Robusta coffee. New planting of Robusta coffee BP 42 x BP 358 was used with Randomized Complete Block Design and 3 replications. Treatments were fertilization as follows : P1 (20 g EMAS + 50 % recognized dosage of inorganic fertilizer (d.a.p.a.)), P2 (10 ml EM 4 + 50 % d.a.p.a.), P3 j (25 g OST + 50 % d.a.p.a.), P4 (5 kg manure + 50 % d a.p.a.) and P5 (d.a.p.a., 23 g Urea, 28 g SP36 and 16 g KCI). The results showed that sum couple, length and sum node of plagiotrophic stems were significantly different from 2 till 6 month after treatment, but it were not significantly different for height and stem diameter: Manure + 50 % d.a.p.a. was the best responses for all variables. EMAS + 50 % d.a.p.a. and EM 4 + 50 % d.a.p.a. had responses as good as inorganic fertilizer: Whereas, OST+ 50 % d.a.p.a. had the lowest responses for all variables

Optimasi Dosis Pupuk Majemuk NPK dan Kalsium pada Bibit Kelapa Sawit (Elaeis Guineensis Jacq.) di Pembibitan Utama

This research was aimed to evaluate the rates of NPK and calcium fertilizers for the growth of oil palm seedling at main nursery. It was conducted in IPB Experimental Station, Cikabayan, Darmaga, Bogor from December 2011 to November 2012. The two factors, NPK and calcium, were arranged in a randomized block design with three replications. The rates of NPK fertilizer (15-15-15) were 0, 115, 230 and 460 g seedling-1. The rates of calcium fertilizer were 0, 5, 10 and 20 g seedling-1. There was no interaction effect observed between NPK and calcium fertilizer. NPK fertilizer, however had the significant quadratic effect on plant height, leaf number, stem diameter and chlorophyll content. Based on morphology variables, recommended optimum rate of NPK 15-15-15 fertilizer was 333 g seedling-1 for eight months. Thus, NPK rates were 7.00, 7.00, 19.45, 59.25, 66.3, 61.55, 58.97 and 54.16 g seedling-1 from first to eight month respectively. The optimum rate of calcium fertilizer was not determined in this experiment

Pertumbuhan Mucuna Bracteata DC. pada Berbagai Waktu Inokulasi dan Dosis Inokulan

Mucuna bracteata DC. is a legume cover crop to prevent erosion and to suppress weed growth. M. bracteata can fix N2 from the air with the help of Rhizobium. M. bracteata get benefit from the symbiosis in the form of increased nodule weight, shoot dry weight, and leaf nitrogen content when the Rhizobium population in the soil is optimal. Application of inoculant is one method to increase the Rhizobium population in the soil. This study aimed to analyze the effects of inoculation times and inoculant rates on M. bracteata growth. The research was conducted in Boyolali, Central Jawa, from February to August 2014. The inoculant contained Bradyrhizobium japonicum and Aeromonas punctata. This experiment was arranged in a randomized block design with two factors and three replications. The first factor was two inoculation times, i.e at the nursery when the seedlings were 2 weeks old and in the field when the seedlings reached 5 weeks old. The second factor was 5 inoculant rates (0, 2, 4, 6, and 8 g per plant). The results showed that inoculation on 5-week-old seedlings was the best result compared to the 2-week-old seedlings. The recommended inoculant rate for Mucuna bracteata was 6.43 g per plant

Pengaruh Dosis Inokulum Cendawan Mikoriza Arbuskula (Gigaspora Rosea) Dan Pupuk Nitrogen Terhadap Pertumbuhan Bibit Kopi Robusta

The experiment was aimed to study the effect of Gigaspora rosea inoculant and nitrogen fertilizer on the growth of coffee Robusta seedling. Coffee seedling which were used came from seedling of hybrid variety from BP 42 and BP 358 crossing, age 1 month. Micorrhiza fungi inoculations which were used came from Gigaspora rosea species. The experiment was conducted at Sukamantri Experiment Station Bogor Agriculture University, from December 1996 to August 1997. The experiment was arranged in Randomized Block Design with three replications. The first factor was dosage of micorhiza inoculation, consisted of 0, 5, 10 and 15 g/seedling. The second factor was dosage of nitrogen consisted of 0, 1.5, 3.0 and 4.5 g/seedling. Fungi inoculation treatment in the dosage 15 g/seedling showed the highest infection percentage but can not increase the growth of coffee seedling. Fungi inoculant in the dosage 5 g/seedling gave the best growth level, showed by variety height of seedling, trunk diameter; leaves total and leaves area, shoot and root biomass, compare to the other fungi inoculation dosages. The highest level of nitrogen in leaf was found in the dosage 4.5 g/seedling. Fungi inoculation in the dosage 5 g/seedling and nitrogen fertilizer in the dosage 3 g/seedling gave the highest level of leaves area and shoot biomass, compare to the other treatment combinations

Mengatasi Cemaran Getah Kuning Pada Buah Manggis (Garcinia Mangostana) Dengan Aplikasi Kalsium Dan Teknologi Lubang Resapan Biopori

Cemaran getah kuning pada buah manggis akan menurunkan kualitas buah. Cemaran getah kuning terjadi pada saat getah mencemari permukaan kulit buah atau aril akibat pecahnya saluran getah kuning. Pecahnya saluran getah kuning berkaitan dengan keberadaan kalsium dalam pericarp buah. Penelitian ini bertujuan untuk (1) mendapatkan dosis dan sumber kalsium terbaik dan efisien dalam menurunkan cemaran getah kuning pada buah manggis, (2) mengetahui pengaruh lubang resapan biopori di dalam USAha mengatasi cemaran getah kuning pada buah manggis, dan (3) mengetahui kombinasi terbaik dari aplikasi kalsium dan lubang resapan biopori untuk meningkatkan serapan dan translokasi kalsium ke buah dan dapat menanggulangi cemaran getah kuning pada buah manggis. Hasil penelitian ini menunjukkan: (1) pemberian kalsium, baik bersumber dari dolomit maupun kalsit, mampu menurunkan cemaran getah kuning pada aril maupun kulit buah manggis, (2) berdasarkan efisiensi dan efektifitas maka dosis pupuk kalsium sebesar 1,6 kg kalsium kalsit/pohon/tahun menjadi dosis terbaik dalam mengatasi cemaran getah kuning, (3) teknologi lubang resapan biopori dapat meningkatkan pertumbuhan dan perkembangan akar muda yang selanjutnya dapat meningkatkan serapan kalsium dan menurunkan cemaran getah kuning setelah 2 tahun aplikasi, (4) kombinasi 1,6 kg kalsium kalsit/pohon/tahun dengan teknologi lubang resapan biopori (LRB) merupakan teknik yang efektif dan mampu meningkatkan persentase produksi buah manggis berkualitas bebas cemaran getah kuning

Tree-based Water Footprint Assessment on Established Oil Palm Plantation in North Sumatera, Indonesia

In a long life cycle of oil palm plantation, sustainable water management is mandatory because irrigation is rarely applied. In order to develop water management for sustainable palm oil production, tree-based water footprint of well-established oil palm plantation was assessed. Field data were collected from February to June 2016 in Dolok Ilir managed by PTPN IV, North Sumatera, Indonesia. Additional data were obtained from interviews on the site and the surrounding estates, reports and references. Results showed that water footprint (WF) for production of fresh fruit bunch (FFB) was 510.69 m3 tonne-1 and crude palm oil (CPO) was 517.79 m3 tonne-1. Green, blue and grey water contributed 94.78%, 0.71% and 4.50% in FFB, and 93.48%, 1.66% and 4.85% in CPO productions, respectively. All green WF was calculated basen on actual value of tree evapotranspiration, therefore, the value was mostly lower than other researchs. Low amount of blue water indicates that the oil palm tree in North Sumatera extracts low amount of ground water. On the other hand, grey water for pollution dilution of fertilizers, pesticides and herbicides were high, i.e., 15.15 m3, 4.77 m3, 3.07 m3 tonne-1 FFB, respectively. It implies that reduction of grey water should be implemented in the near future through precission farming