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STRATEGI PEMUPUKAN TANAMAN KARET DALAM MENGHADAPI HARGA KARET YANG RENDAH
Get PDFPemeliharaan tanaman karet melalui pemupukan merupakan salah satu langkah penting yang harus dilakukan untuk mencapai pertumbuhan dan produksi yang optimal. Akhir-akhir ini ketersediaan pupuk yang terbatas, harga yang terus meningkat, dan harga karet yang rendah menyebabkan kegiatan pemupukan pada perkebunan karet sering tertunda. Selain penundaan kegiatan pemupukan juga terjadi pengurangan dosis dan bahkan meniadakan kegiatan pemupukan. Tulisan ini bertujuan untuk mengkaji hasil-hasil penelitian dalam upaya peningkatan efisiensi pemupukan pada tanaman karet sehingga biaya pemupukan dapat dikurangi. Hasil-hasil penelitian sebelumnya menunjukkan bahwa pemupukan dapat dikurangi sampai 75% dari dosis pupuk tunggal apabila menerapkan teknologi pemupukan menggunakan pupuk majemuk dengan tambahan slow release agent yang sering disebut dengan Slow Release Fertilizer (SRF) dan upaya lain dengan menggunakan kombinasi pupuk tunggal dengan pupuk hayati. Selain itu penentuan dosis rekomendasi harus mempertimbangkan sifat tanah sehubungan dengan kapasitas tanah dalam menyediakan unsur hara untuk tanaman, faktor lingkungan yang mempengaruhi efisiensi pemupukan, serta kebutuhan tanaman akan unsur hara sesuai dengan umur, produksi, dan kesehatan tanaman. Pada kondisi pekebun yang mengalami kesulitan melakukan pemupukan akibat harga karet yang rendah maka penundaan pemupukan selama dua tahun belum memberikan efek kerugian finansial bagi pekebun
SIFAT MEKANIK RUBBER SEAL KATUP TABUNG GAS LPG PADA VARIASI UKURAN DAN DOSIS SILIKA
Get PDFKeputusan PT. Pertamina (Persero) untuk mengganti warna karet perapat (rubber seal) pada katup tabung gas LPG dari hitam menjadi merah menimbulkan permasalahan tersendiri. Â Pemakaian warna merah pada karet perapat berpengaruh terhadap desain kompon karena menggunakan silika sebagai bahan pengisi. Berbeda dengan carbon black, silika yang beredar di pasar memiliki keterbatasan ukuran partikel. Ukuran partikel bahan pengisi berpengaruh terhadap sifat mekanik dari produk karet. Tujuan dari penelitian ini untuk mempelajari pengaruh jenis dan dosis silika dengan ukuran partikel yang berbeda terhadap sifat fisika dari vulkanisat karet perapat gas LPG. Silika dengan 3 variasi ukuran partikel (luas permukaan 55, 115, dan 175 m2/g) dan 5 variasi dosis (5, 10, 15, 25, dan 30 bsk) digunakan sebagai bahan pengisi untuk pembuatan kompon karet perapat gas LPG. Kompon yang dirancang kemudian diuji sifat fisikanya sesuai persyaratan di dalam SNI 7655:2010. Hasil penelitian menunjukkan bahwa semakin besar ukuran partikel silika delta torsinya semakin rendah. Adapun perbedaan dosis silika yang digunakan menunjukkan bahwa penambahan silika di atas 15 bsk untuk jenis 115 m2/g, dan di atas 10 bsk untuk jenis 175 m2/g menyebabkan nilai pampatan tetapnya tidak lagi memenuhi persyaratan SNI. Sementara itu pengaruhnya terhadap nilai perpanjangan putus tidak terlalu signifikan untuk silika 115 m2/g, sedangkan untuk silika 175 m2/g, perpanjangan putus naik sampai dosis silika 15 bsk dan turun kembali pada penambahan silika di atas 15 bsk
PENGUJIAN BEBERAPA ALTERNATIF TEKNIK PENANAMAN TANAMAN KARET DI LAHAN GAMBUT
Get PDFLahan yang ideal untuk pertumbuhan tanaman karet semakin terbatas sehingga banyak petani dan perusahaan mencari lahan pengembangan karet di daerah non tradisional seperti lahan gambut. Penanaman karet pada areal gambut terdapat hambatan seperti miskinnya hara gambut dan tanaman akan tumbang pada saat tanaman sudah besar. Masih terbatasnya informasi hasil penelitian terkait pertumbuhan tanaman karet di lahan gambut, sehingga penelitian ini dilakukan untuk mengetahui pertumbuhan dan cara mengatasi kendala penanaman karet di lahan gambut. Penelitian ini dilaksanakan di lahan gambut dengan kedalaman 1,5 - 2 m dan tingkat kematangan gambut sapris. Klon karet yang digunakan adalah IRR 118. Penelitian ini merupakan penelitian eksperimen, menggunakan rancangan acak kelompok dengan empat perlakuan dan enam ulangan. Perlakuan yang diuji adalah 1) Kontrol (cara penanaman biasa dengan bahan tanam konvensional), 2) Penanaman dalam (lubang tanam dibuat lebih dalam sehingga penanaman dilakukan sampai payung pertama dan menggunakan bibit konvensional), 3) Modifikasi bahan tanam (ketinggian okulasi 30 cm), dan 4) Modifikasi bahan (ketinggian okulasi 50 cm). Hasil penelitian menunjukkan bahwa pertumbuhan tanaman karet klon IRR 118 memiliki pertumbuhan yang baik sehingga pada umur lima tahun rata-rata lilit batangnya telah mencapai 45 cm. Pengaruh perlakuan teknik penanaman terhadap pertumbuhan dan tanaman yang miring atau tumbang sampai dengan umur tanaman lima tahun belum terlihat
THE ROAD TO ABRABOR: ASSOCIATIONISM IN THE DEVELOPMENT OF THE BRAZILIAN NATURAL RUBBER INDUSTRY
No full textBrazilian natural rubber industry has lived its greatest expansion in the past 25 years. The State of São Paulo was the main area of expansion and, the development of associative activities in this region were paramount in helping to establish a wide net of positive interactions between farmers, processors and government with crucial benefits to the establishment of the Brazilian Natural Rubber Industry. Further, natural rubber cultivation has been expanded to neighboring States of São Paulo, mainly: Mato Grosso, Mato Grosso do Sul, Goias, Tocantins, Minas Gerais, EspÃrito Santo, Bahia and later Paraná. Such expansion has led local industry agents also to create associations that recently, in the year of 2016, came together under one Federal representation named ABRABOR. This paper intends to describe such phenomenon through a multi-case study of the current institutions associated to ABRABOR analyzing each state characteristics together with each institution incentive offers. Next, this characterization will be analyzed factoring in the compatibility of the governance structure of each entity, regarding the compliance with the demand of associates on each State, thus providing resources for an efficiency assessment of such groups. Later, the same criteria will be applied for analyzing their efficiency at national level representation. Keywords: collective action, polycentric Framework, industry strategy, associativism, natural rubberÂ
SUSTAINABILITY ASSESMENT IN NATURAL RUBBER INDUSTRY: CASE OF A SRI LANAKAN CREPE RUBBER FACTORY
No full textBased on a case study in a Sri Lankan crepe rubber mill, this study performs a comprehensive sustainability assessment to uncover the underlying potential of improving the performance of the NR processing sector. This sustainability assessment consists of three steps: 1. quantification of mill`s resource use, economic loss, greenhouse gas emissions, and the impact on workers using material flow analysis (MFA), material flow cost accounting (MFCA), environmental life cycle assessment (ELCA), and social life cycle assessment (SLCA). 2. Selection and proposal of improvement options with the help of Pareto and What-if analyses, field interviews, and literature; and 3. Validation of the suggested improvement options via the re-execution of MFA, MFCA, LCA, and SLCA. With the support of this methodical hierarchy, the underlying economic, environmental, and social hotspots in the current manufacturing process can be identified, and moreover, the degree of improvement potential can also be assessed. Keywords: natural rubber processing, material flow analysis (MFA), material flow cost accounting (MFCA), environmental life cycle assessment (ELCA), social life cycle assessment (SLCA
IDENTIFICATION AND MECHANISM STUDY OF THE GERMIN-LIKE PROTEINS FAMILY GENE OF HBGLP01 FROM RUBBER TREES
No full textCorynespora leaf fall disease (CLFD) is one of the most destructive leaf diseases in the rubber plantations. Cultivation of resistant clones developed from disease resistant germplasm is the most efficient way to control this disease. Identification of resistant genes is the basis for selecting germplasm resources of disease resistance to breed resistant varieties. From recent studies, we have cloned a member of the germin-like proteins family encoding HbGLP01 gene by cDNA amplified fragment length polymorphism technique. This gene was able to respond to pathogen infection in resistant germplasm, and had the potential of becoming a target gene in early molecular diagnosis of rubber tree germplasm. In this study, we propose to identify HbGLP01 gene(s) from complete genome sequence database of rubber trees, and analyze the genetic evolutionary relationships of the germin-like protein family genes. Its expression characteristics toward biotic stress, exogenous hormone treatment in the resistant/susceptible germplasm of rubber trees will be studied based on the analysis of tissue specific expression. These results will make clear of the roles of these important genes in resistance and defense signaling pathway in rubber trees. Keywords: Hevea brasiliensis, Corynespora leaf fall disease, germin-like proteins, family encoding gene HbGLP01, resistant genes, rubber, molecular diagnosis, germplasm, genetic evolutionary relationship
INVESTIGATION ON RENEWABLE ENERGY INTEGRATED DRYING SYSTEM FOR PRODUCTION OF SUPERIOR QUALITY SHEET RUBBER
No full textThe conventional practice of drying sheet rubber is by biomass combustion with firewood as fuel in a smoke house. The heat balance of existing conventional smoke houses was studied and it revealed that, out of 3550 MJ thermal energy supplied as heat input, only 24.2 per cent of energy is utilized for drying the rest being lost through exhaust, walls and doors, moisture in fuel and other unaccountable losses . In order to enhance the drying efficiency, obtain a high quality of NR, reduce pollution, achieve energy substitution through renewable fuel, an attempt was made to develop a renewable energy integrated drying system. This paper describes field investigation results of an integrated drying system installed at a group processing centre at the Elavampadam Rubber Producers’ Society (EMRPS), Kerala, India. The hot air temperature is maintained at 60°C, the optimum temperature for drying sheets by this system. Hot air from solar air heaters, producer gas and biogas were integrated in the drying chamber for supply during sunshine and off-sunshine hours. The results revealed that, drying time was reached within 72 hours by using this integrated drying system compared to 144 hours with conventional smoke drying. Similarly, reduction of the desired moisture content from 25 per cent (d.b) to 5.3 per cent (d.b) was obtained during the process. Average thermal efficiency of integrated drying system was found to be 50.8 per cent. A superior quality of sheet rubber was obtained using the renewable energy integrated drying system comparing to RSS 1 to RSS 4 using conventional drying practice. The integrated drying system completely eliminates smoke during the drying process ultimately eliminating health hazards in the rubber processing industry and achieving attractive price for the product.Keywords:  renewable fuel, integrated drying system, solar air heaters, biomass gasifier,  biogas, drying time, qualit
BASIC DESIGN OF PROCESS ENGINEERING FOR EPOXIDIZED NATURAL RUBBER PRODUCTION AS RAW MATERIAL FOR OIL RESISTANT PRODUCTS
No full textNatural rubber of Hevea brasiliensis is a natural polymer which has good damping properties and high elasticity. However, the natural rubber molecule is a nonpolar hydrocarbon polymer which easily swells in oil. Epoxidizing the double bond of the natural rubber molecule is an effort to increase its polarity thereby increasing its resistance to oil. Several of its physical properties will also improve. Epoxidized natural rubber is made from the insitu epoxidation of the rubber molecule in the latex phase using performic acid made from hydrogen peroxide and formic acid. The aim of the experiments in this study was to design the process engineering of the epoxidation reaction from concentrated latex. The reaction was carried out at a temperature of 70 °C for 5 hours with the dose of hydrogen peroxide at 0.75 mol/mol isoprene unit and 0.4 mol/mol isoprene unit of the formic acid dose. The exothermic reaction occurred in a Batch Stirrer Tank Reactor (BSTR) which was equipped with a water cooling system to keep the reaction temperature constant. The reaction product was then neutralized with the addition of ammoniac and sodium thiosulphate in a neutralization tank. The product was then coagulated using a thermal extruder at 80-90 °C to produce Epoxidized Natural Rubber with 40% mol epoxy percent (ENR-40). The ENR was then washed with water to remove the acid residue. At the end, the ENR product was dried at 105 °C. The result showed that this basic design can be used as a reference to produce epoxidized natural rubber from the pilot scale to an industrial scale. Some parameters such as temperature, pressure, time conducted at each stage of the process, process flow diagram, process equipment, production efficiency, and the technoeconomy aspect need consideration in the design.Keywords: batch stirrer tank reactor, concentrated latex, epoxidized natural rubber, oil resistance, process desig
SOILS UNDER HEVEA IN PENINSULAR MALAYSIA: IDENTIFICATION AND DISTRIBUTION OF CLAY MINERALS
No full textClay mineralogy of 23 different series of soils from different localities in Peninsular Malaysia and belonging to a wide range of parent materials are reported and discussed. Various techniques of determination were employed. It was found that several types of clays occur in Malaysia soils. The presence of a specific type of clay mineral was found to be useful tool to predict the type of parent material as well as weathering stage of the parent material. Additionally, it was shown that in the humid environment experienced in Malaysia, degeneration of 2: 1 clays was rapid. The information on clay mineralogy will be useful to predict the fertility of the soils so that proper fertiliser recommendation can be made.Keywords: mineralogy, soil, Hevea, tropical, weathere
ANALYSIS OF MOLECULAR MARKERS LINKED TO CORYNESPORA LEAF FALL DISEASE RESISTANCE IN RUBBER PLANTS
No full textRubber cultivation in Indonesia and other major natural rubber producing countries faced the constraint of the Corynespora leaf fall (CLF) disease attack that significantly reduced the production of latex.  The use of resistant rubber clones as a planting material is one of the effective and economic solutions in CLF disease control. The rubber breeding program to obtain superior clones resistant to CLF disease is constrained by the length of time required for the selection process. The progress of the molecular biology provides a chance to solve this problem. To identify moleculer markers linked with resistance to CLF disease a series of experiments that consisted of genetic analysis of C. cassiicola isolates, evaluation of the CLF disease resistance level of the rubber germplasm accessions and identification of the QTL  linkage to CLF disease on the rubber tree were carried out. The rDNA-ITS sequences and virulence analysis of 23 C. cassiicola isolates showed that there were 5 haplotypes of isolates and  that differences were present in the virulence level of isolates to the rubber clones tested. Three isolates collected from rubber clones PR 303, RRIM 600 and Tjir 1 have a very high virulence level. Resistance test of 56 rubber germplasm accessions with four of C. cassiicola isolates showed that 12 accessions could be classified as very resistant, 13 as  resistant, 23 as susceptible and 8 as very susceptible. Three accessions of the IRRDB 1981 population namely PN 451, PN 494 and PN 604 have better resistance levels compared to Wickham population. The resistant (BPM 1) and susceptible (RRIM 600) rubber clones were selected as a parent clones to obtain a mapping population for QTL analysis that produced 30 F1 plants and 74 embryonic F1. Linkage analysis by using 30 selected SSR primers showthat there were four linkage groups on the LOD 3 with total 8 loci, while LOD 2 had two linkage groups with total 11 linked loci. QTLs linked to CLF disease have not been identified on the linkage map, but based on the single marker analysis, four loci (EHB70, EHB081, EHBp18 and SSRH548) associated with two isolates used (CC-06 and CC-22) were found. The informations obtained in this study are the first step for the development of Marker Assisted Selection (MAS) of rubber resistant to CLF disease. Keywords: Corynespora  cassiicola, genetic linked map, Hevea brasiliensis, QTL, rDNA-IT