Judul: Inventory of Ornamental Plant Diseases in Sukamantri Village, Tamansari District, Bogor Regency, West Java
Abstrak: Tanaman hias merupakan salah satu komoditas hortikultura yang memiliki nilai ekonomi dan estetika yang tinggi. Di Indonesia, penelitian hama dan penyakit pada tanaman hias relatif terbatas. Penelitian ini bertujuan untuk menginventarisasi penyakit tanaman hias di Desa Sukamantri, Kecamatan Tamansari, Kabupaten Bogor, Jawa Barat. Penelitian meliputi wawancara, pengambilan sampel, deteksi dan identifikasi penyakit, pengamatan penyakit, serta analisis data. Wawancara dilakukan dengan menggunakan kuesioner terstruktur kepada 20 petani tanaman hias. Sampel diambil dari 13 jenis tanaman hias. Pengamatan dilakukan terhadap tanaman yang bergejala penyakit dan spora fungi patogen diidentifikasi secara mikroskopik. Pengamatan penyakit dilakukan sebanyak empat kali pada 50 tanaman setiap jenisnya. Analisis data pengamatan penyakit dilakukan menggunakan Microsoft Excel 2010. Hasil penelitian menunjukkan bahwa mayoritas petani tanaman hias di Sukamantri berumur 41 – 50 tahun, tingkat pendidikan sekolah menengah atas, pengalaman bertani 2 – 10 tahun, dan penyewa lahan. Sebanyak sembilan fungi yang berasosiasi dan menyebabkan penyakit pada tanaman hias yaitu bercak daun Bipolaris (Bipolaris sp.), busuk daun (Colletotrichum sp.), busuk pucuk (Phytophthora sp.), hawar daun Fusarium (Fusarium sp.), hawar daun Pestalotia (Pestalotia sp.), bercak daun Cercospora (Cercospora sp.), karat daun Phakopsora (Phakopsora sp.), mati pucuk (Botryodiplodia sp.), dan karat daun Puccinia (Puccinia sp.). Karat daun Puccinia adalah penyakit yang paling dominan dengan tingkat insidensi penyakit tertinggi.
Keyword: farmer, fungi, Puccinia leaf rust

Judul: Hama dan Penyakit pada Tanaman Hias di Kebun Salsabiila Nursery Cugenang, Jawa Barat
Abstrak: Tanaman hias adalah satu komoditas penting di Indonesia. Organisme pengganggu tanaman (OPT) menjadi salah satu pembatas produksinya. Namun, informasi terkait OPT pada tanaman hias sangat terbatas. Penelitian bertujuan untuk mendeteksi dan mengidentifikasi hama dan penyakit pada tanaman hias kastuba (Euphorbia pulcherrima), cocor bebek berbunga (Kalanchoe blossfeldiana), dan tapak dara (Catharanthus roseus) di Kebun Salsabiila Nursery, Kecamatan Cugenang, Kabupaten Cianjur, Jawa Barat. Pengamatan OPT dilakukan setiap minggu sebanyak empat kali dengan interval 1 minggu. Identifikasi OPT berdasarkan menunjukkan gejala dan bentuk morfologi OPT. Hama utama yang ditemukan adalah kutu kebul dan kutu putih pada tanaman kastuba, ulat grayak (Spodoptera litura) pada tanaman cocor bebek, dan trips pada tanaman tapak dara. Penyakit yang ditemui adalah embun tepung (Phyllactinia poinsettiae) dan kudis (Phyllactinia poinsettiae). pada tanaman kastuba, bercak daun (Stemphylium solani) pada tanaman cocor bebek, Poinsettia mosaic virus pada tanaman kastuba, dan busuk batang (Phytophthora cactorum) pada tanaman cocor bebek. Penyakit bercak daun adalah penyakit yang paling dominan dengan tingkat insidensi penyakit paling tinggi diantara semua penyakit yang diamati.
Keyword: Kalanchoe, periwinkle, pests and diseases, poinsettia

Judul: Exergy Analysis of Membrane Utilization for Solution Separation in LiBr-H2O Absorbtion Refrigeration System
Abstrak: Absorbtion refrigeration system provides prominent advantages in tems of environmental impact and energy consumption. Absorbtion refrigeration system uses natural refrigerant, such as water, which gives no harm to the environment. In terms of energy consumption, it requires heat to regenerate refrigerant from its absorber and provide the refrigeration effect. This form of energy is preferred since heat can be supplied from various sources, including waste heat and renewable energy, and thermodynamically categorized as low quality energy. However, effectiveness of refrigerant regeneration could only be obtained if the temperature is high enough. In this study, the heat utilization in the regeneration process will be eliminated by introducing membranes for separating the refrigerant from the absorber. Specifically, the objectives of this research are to :1) to study the absorbtion mechanism of water vapor by LiBr-H2O solution in a controlled condition, 2) to study the regeneration process of LiBr-H2O using reverse osmosis (RO) membrane and vacuum membrane distillation (VMD) when applied in LiBr-H2O absorbtion refrigeration system, 3) to perform the energy and exergy analysis in LiBr-H2O absorbtion refrigeration system using RO membrane. The membrane was used as a tool to separate the refrigerant from absorbent which performs as regeneration process in conventional absorbtion system. As separation component, RO membrane employs pressure to oppose the osmotic pressure and pass certain component through the pores. While, VMD employs vacuum pressure and thermal, so that the substance to be transported through the membrane is in form of vapor. The result shows that absorbtion rate of water vapor by LiBr-H2O solution was influenced by solution concentration, temperature, humidity and pressure. The highest absorbtion rate was 0.031 g/minute which was occurred at temperature 40°C, RH 70% and solution concentration 60%. Prediction model was developed to calculate the absorbtion parameter inspite of P-T-X diagram.The highest water vapor absorbtion in absorber using spiral wound module-based RO membrane occurred at initial concentration of 30%, wich is the highest concentration used in the experiment. Increasing of operation pressure during separation process will increase permeation flux but decrease rejection factor.Unexpectedly, permeate of the RO membrane still contain LiBr at concentration 7w/w %-9w/w%, which affect the achievable cooling temperature and cooling capacity. Optimization of regeneration using VMD was conducted with response surface methodology (RSM) and the result show that highest permeate flux (0.93 kg.m-2.s-1) can be achived at initial concentration of 47.5%, temperature of 80°C and flow rate of 1.9 L.min-1.COP obtained in absorbtion refrigeration system using RO membran with initial concentration 20% was in the range of 1.147-1.171. Exergy analysis shows that increasing pressure of RO membrane at concentration 20% increased the irreversibity.On the other hand, exergy analysis on VMD shows that higher concentration and temperature will increased irreversibility.
Keyword: refrigeration, absorbtion, reverse osmosis, vacuum membrane distillation, energy, exergy