Judul: Evaluasi Day A Hasil Ubijalar Pentaploid Dan Ubijalar Lokal Harap An Di Dataran Tinggi Dan Dataran Rendah
Abstrak: Ipomoea trifida mempakan kerabat liar ubijalar yang paling berpotensi dalam pemuliaan tanaman ubijalar. Persilangannya dengan ubijalar terbudidaya dapat dipergunakan untuk merakit tanaman pentaploid yang menampilkan karakter daya hasil tinggi, resisten terhadap hama dan penyakit, serta berkadar bahan kering tinggi. Klon ubijalar pentaploid dihasilkan melalui persilangan antara ubijalar heksaploid dengan spesies tetraploid. Produksi ubijalar di Indonesia sampai saat ini tidak mengalami peningkatan, di samping itu tidak ada perluasan areal dan kenaikan hasil. Sehubungan dengan usaha peningkatan produksi maka usaha seleksi, pemuliaan dan pengembangan verietas bam yang memenuhi kebutuhan perlu dilakukan baik sebagai bahan pangan maupun bahan baku industri. Klon-klon yang dihasilkan dari pemuliaan perlu diuji lebih lanjut dalam lingkungan luas sehingga klon-klon ubijalar dapat diketahui adaptasinya dan daya hasil yang baik untuk keperluan pangan maupun industri. Percobaan ini bertujuan untuk mengevaluasi daya hasil ubijalar pentaploid dan tetuanya serta ubijalar lokal harapan. Disamping itu untuk memilih klon-klon ubijalar dengan daya hasillebih baik di dua lokasi yang berbeda.
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Judul: Seleksi daya hasil, kualitas umbi, ketahanan penyakit kudis dan kestabilan klon dalam pemuliaan ubijalar
Abstrak: Ubijalar merupakan salah satu tanaman pangna yang dapat dimanfaatkan sebagai bahan baku industri. Kualitas umbi merupakan karakter yang dijadikan kriteria untuk kegunaan industri. Indonesia yang kaya keanekaragaman plasma nutfah ubijalar dapat menjadi sumber genetik untuk program permulian. Melalui penelitian Hibah Bersaing I. FMIPA IPB telah mengevaluasi 253 kon ubijalar lokal asal Sumatera, Jawa dan Irian Jaya. Sebanyak 110 klon ubijalar telah diseleksi sebagai koleksi kerja untuk program permulian ubijalar. Dua puluh delapan klon ubijalar lokal Indonesia dari koleksi kerja tersebut dan dua varietas pemabnding yaitu varietas nasional Pramabanan dan introduksi SQ-27 terpilih sebagai bahan penelitian ini. Percobaan berlangsng di enam lokasi (Pacet, Muara, Dramaga di Jawa Barat, dan Wamena, Manggoapi, Prafi di Irian Jaya) selam dua tahun (1994/1995 dan 1995/1996)bertujuan menyeleksi klon ubijalar lokal dengan kombinasi karakter daya hasil tinggi, kualitas umbi baik, tahan penyakit kudis daun Elsinoe batatas, dan berperagaan stabil pada rentang keadaan lingkungan luas.
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Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
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