Bambang Pramudya

Identification of flood area in the coastal region using remote sensing in Karawang Regency, West Java

Flooding often occurs in the lowlands, while the area is usually a rice production centres which affects the rice crop. Rice fields is generally located on fluvial plains and usually located in coastal areas, with relatively lower altitudes than roads or settlements. Physically wetland is an area flooding hazard and wetlands tend to longer floods than surrounding areas. Flood-hazard areas are formed due to sedimentation and usually at the confluence of river. This area is a fertile area for agriculture, has shallow ground water which is well suited for residential and urban areas. Karawang regency is one of the largest producers of rice commodities in West Java, therefore the Karawang regency government faces a challenge in maintaining the level of rice production due to global climate change that worsen the threat of flood hazard, in addition to land use change and increasing population. Based on the results of the spatial analysis from period of 2000 to 2006 the wetland area have been converted up to 7,493 ha. For the period of 2006 to 2015 wetland area have been converted up to 14,416 ha. Utilization of Geographic Information System with a model of Cellular Automata - Marcov Chain is an appropriate method for studying the phenomenon of expansion of build ups land in coastal region. The primary data used in the research is a land cover map of 2000, 2006 and 2015, which were the results of the multispectral classification of Landsat. The prediction of land cover change for the next fifteen years shows a continuous increase in built up area. The expansion of built up area and the possibility of widespread flood hazard areas, have inverse relationship with the decreasing of agricultural land area.

Spatial Modeling on Coastal Land Use/Land Cover Changes and its Impact on Farmers

Coastal areas are an attractive place to live and/or to perform community activities, therefore coastal areas are vulnerable to both natural and artificial damage and destruction. This study presents the problem of changes in land cover/land use in coastal areas caused by humans. Rapid environmental change due to population growth will require food, shelter and other infrastructure. The 2010-2015 population growth rate of 1.37% or the population grew 6.86% from 2010. Population growth and industrial development increased demand for housing, roads and industrial infrastructure that encouraged land conversion. Agricultural land is the most converted land. Land use in 2000, for paddy fields area was 120,371 ha (62.83%) and pond area was 4,484 ha (2.34%). In 2015 paddy fields were degraded to 98.462 ha (51.41%), and pond area to 20,839 ha (10.88%). Markov modeling had a correlation of 97.72% “r” square value, indicated this modeling could be done to predict land cover change until 2031. In an effort to optimize irrigation field potential and increase of farmers income, minapadi system (combined farming/fish kept in the paddy fields) was done by previous monoculture farmers to diversification system agriculture. This pattern could increase the productivity of the land and also could increase the diversity of agricultural produce, increase farmer income, increase soil fertility, and also reduce pest disease in rice plants. The purpose of this study is to model spatial changes in land cover/coastal land use and its effect on rice production, fish paddy field production and fishpond production in coastal habitat.

Alternatif Model Usahatani Konservasi Tanaman Sayuran di Hulu Sub-DAS Cikapundung

ABSTRAK. Karat putih yang disebabkan oleh Puccinia horiana merupakan salah satu penyakit pada krisan yang dapat menimbulkan kehilangan hasil sampai 100% . Selama ini untuk mengendalikan patogen tersebut, petani sering menggunakan pestisida kimiawi. Hal tersebut sangat mengkhawatirkan mengingat penggunaan fungisida sintetik secara berlebihan dapat mencemari lingkungan yang membahayakan bagi kehidupan makhluk hidup. Oleh karena itu, cara pengendalian alternatif yang efektif dan aman bagi lingkungan diperlukan untuk mengendalikan penyakit karat putih pada krisan. Salah satu alternatif cara pengendalian penyakit karat yaitu dengan mengaplikasikan biopestisida yang ramah lingkungan. Penelitian dilakukan di laboratorium, rumah kaca, dan rumah plastik Kebun Percobaan Balai Penelitian Tanaman Hias (1.100 m dpl), pada bulan April 2009 sampai Februari 2010. Tiga spesies bakteri antagonis sebagai bahan aktif biopestisida (Bacillus subtilis Cs 1a, Corynebacterium sp.1, dan Pseudomonas flurescens 3 Sm) dan bahan pembawa (campuran antara ekstrak kascing, molase, gula pasir, dan atau kentang), masing-masing diformulasi dalam 12 jenis formula biopestisida cair. Formulasi biopestisida difermentasikan selama 3 minggu dalam keadaan aerobik menggunakan biofermentor. Viabilitas bahan aktif dalam bahan pembawa diuji setiap bulan, yaitu pada periode sebelum dan sesudah fermentasi. Hasil penelitian menunjukkan bahwa populasi bahan aktif setelah difermentasi selama 3 minggu selalu meningkat, populasi bahan aktif sebelum fermentasi sejumlah 105 cfu/ml meningkat menjadi 106-7 cfu/ml. Dua bulan setelah fermentasi, populasi bahan aktif biopestisida masih tetap tinggi yaitu berkisar antara 106-11 cfu/ml. Perlakuan ekstrak kascing + gula pasir + B. subtilis + P. fluorescens + Corynebacterium pada tingkat konsentrasi 0,3% merupakan perlakuan terbaik. Disamping dapat menekan intensitas serangan P. horiana (38,49%), formulasi biopestisida tersebut juga dapat menaikkan hasil panen bunga krisan layak jual sebanyak 14,58%. ABSTRACT. Hanudin, W. Nuryani, E. Silvia, I. Djatnika, and B. Marwoto. 2010. Formulation of Biopesticide Containing Bacilllus subtilis, Pseudomonas fluorescens, and Corynebacterium sp. for Controlling White Rust Disease on Chrysanthemum. White rust caused by Puccinia horiana is one of the contagious diseases of chrysanthemum that is able to cause yield losses up to 100%. Chemical synthetic fungicides have been used to control the disease. Because of harmful effects of the synthetic fungicides, the other alternative measure to control the disease have to be developed in order to support the sustainable farming system. One of the recommended control measures is the application of biopesticide which is environmentaly friendly. The experiments were conducted in the laboratory, glasshouse, and plastichouse of Indonesia Ornamental Crops Research Institute (1,100 m asl), from April 2009–February 2010. Three candidates of biocontrol agents, i.e. B. subtilis Cs 1a, Corynebacterium sp.1, and P. fluorescens 3 Sm, were formulated with organic basal medium made from fermented worm manure, molasses, sugar, and or potatoes extracts. Twelve formulations were tested for their effectiveness to control the disease in the field. The viability of the biocontrol agents in the formulations was monthly tested before and after fermentation process during storage. Population of the biocontrol agents, after fermentation for 3 weeks was increased from 105 to 106-7 cfu/ml. Two months after fermentation the population of the biocontrol agents was still high (106-11 cfu/ml). The results showed that the formulation of vermicompost + sugar + B. subtilis + P. fluorescens + Corynebacterium at the concentration level of 0.3%, was proven to be the best treatment. The treatment was effective to supress white rust up to 38.49%, and could also increase the yield of marketable chrysanthemum flowers up to 14.58%.ABSTRAK. Pertanaman jeruk saat ini, di Kabupaten Karo, memperlihatkan produktivitas rendah dan umur tanaman yang pendek. Hal tersebut disebabkan oleh serangan Phytophthora spp. yang merupakan patogen penyebab penyakit busuk pangkal batang pada tanaman jeruk. Penelitian bertujuan mengidentifikasi Phytophthora spp., patogen penyebab penyakit busuk pangkal batang pada tanaman jeruk. Penelitian dilakukan di Laboratorium Penyakit, Kebun Percobaan Tanaman Buah Berastagi dalam bulan Januari-Februari 2007. Daerah pengambilan sampel ialah di Desa Sumbul Kecamatan Kabanjahe, dan Desa Barusjahe Kecamatan Barusjahe. Hasil penelitian menunjukkan bahwa jamur Phytophthora palmivora, P. citrophthora, dan P. parasitica ditemukan di Desa Sumbul. Jamur P. citrophthora dan P. parasitica juga diperoleh di Desa Barusjahe. Sporangia dan misellium P. palmivora di Desa Sumbul berwarna merah jambu dan putih, P. citrophthora berwarna putih dan hijau kehitaman, serta P. parasitica berwarna putih dan kuning muda, sedangkan di Desa Barusjahe P. citrophthora berwarna putih dan merah jambu dan P. parasitica berwarna putih. Ukuran (panjang x lebar) sporangia P. palmivora (33-45) x (30-50) μm, P. citrophthora di Desa Sumbul (40-50) x (34-50) μm, dan di Desa Barusjahe (30-45) x (30-45) μm, P. parasitica di Desa Sumbul (33-35) x (29-30) μm, dan di Desa Barusjahe (30-40) x (28-30) μm. Ukuran sporangiofor P. palmivora pada umumnya sebesar 6,25-250 μm, panjang sporangiofor P. citrophthora di Desa Sumbul antara 25-68,75 μm dan di Desa Barusjahe 12,5-100 μm, sedangkan panjang sporangiofor P. parasitica di Desa Sumbul 43,75-162,5 μm dan di Desa Barusjahe 6,25-150 μm. Spesies phytophthora yang paling banyak ditemukan di Desa Sumbul adalah P. palmivora, sedangkan di daerah Barusjahe adalah P. citrophthora. Hasil identifikasi yang diperoleh dari penelitian ini akan bermanfaat dalam menentukan cara pengendalian Phytophthora spp. pada tanaman jeruk. ABSTRACT. Marpaung, A.E., F.H. Silalahi, and E.I.Y. Purba. 2010. Identification of the Causal Agent of Brown Rot Gummosis on Citrus in Karo Region. Citrus cultivation in Karo region has exhibited low yielding and short plant lifetime. This condition was caused by the infection of Phytophthora spp., the causal agent of brown rot gummosis on citrus. The objectives of the research was to identify the occurence of Phytophthora spp. on citrus plants. The research was conducted in Berastagi Fruits Plant Research Farm, from January to February 2007. The samples were collected from Kabanjahe District at the viilage of Sumbul and Barusjahe. The results indicated, that Phytophthora palmivora, P. citrophthora, and P. parasitica were obtained from Sumbul village, while P. citrophthora and P. parasitica were also found in Barusjahe village. The color of sporangia and misellium of P. palmivora originated from Sumbul Village was white, P. citrophthora was white and dark green, and P. parasitica were pink and yellow, meanwhile the color of at P. citrophthora obtained from Barusjahe village were white and pink and P. parasitica was white. The size of sporangia P. palmivora was (33-45) x (30-50) μm, P. citrophthora at Sumbul Village was (40-50) x (34-50) μm, and from Barusjahe Village was (30-45) x (30-45) μm, P. parasitica at Sumbul Village was (33-35) x (29-30) μm and Barusjahe Village was (30-40) x (28-30) μm. The general length of sporangiofor P. palmivora was 6.25-250 μm. The length of sporangiofor P. citrophthora at Sumbul Village was 25-68.75 μm and at Barusjahe Village was 12.5-100 μm, even though P. parasitica at Sumbul Village was 43.75-162.5 μm and Barusjahe Village was 6.25-150 μm. The most species of phytophthora found at Sumbul Village was P. palmivora and at Barusjahe Village was P. citrophthora. The result of the identification wil beneficial for the development of easier control measures of Phytophthora spp. disease on citrus.