Judul: Pendugaan Nilai Heritabilitas Kandungan Bahan Kering Umbi Pada Tanaman Ubi Jalar (Ipomoea Batatas (L) Lam)
Abstrak: Tujuan penelitian ini adalah untuk menduga nilai heritabilitas kandungan bahan kering umbi pada tanaman ubi jalar. Delapan belas klon ubi jalar [Ipomoea batatas (L.) Lam.] telah diambil secara acak dari suatu percobaan pendahuluan berdasarkan kandungan bahan kering umbi, pembungaan dan potensi hasil. 18 klon tersebut, empat diantaranya merupakan hasil introduksi dari CIP, sedangkan selebihnya merupakan hasil koleksi dari berbagai provinsi di Indonesia. Ke 18 klon ini dipelihara pada suatu tempat yang terisolasi dari tanaman ubi jalar lainnya dan dibiarkan menyerbuk terbuka secara alamiah dengan bantuan lebah. Tanaman keturunan diperoleh dari biji hasil penyerbukan terbuka pada masing-masing tetua betinanya. Nilai heritabilitas kandungan bahan kering umbi diduga dengan cara regresi tanaman keturunan (0) terhadap tetua betinanya (P) dan menggandakan nilai koefisien regresi tersebut, h² = 2bop. Dari penelitian ini diperoleh nilai heritabilitas kandungan bahan kering umbi yang cukup tinggi yakni 61.2 + 19.5 (famili) dan 58.8 -9.8 (individu).
Keyword: Ipomoea batatas (L) Lam, Heritability

Judul: Kemampuan Silang Antara Ipomoea batatas Berdaging Umbi Ungu Dengan Kerabat Liarnya  (Ipomoea trifida) Diploid
Abstrak: Ubi jalar merupakan makanan yang banyak dikonsumsi di negara berkembang. Ubi jalar dapat dimanfaatkan sebagai bahan baku industri. Selain umbinya, daun ubi jalar dapat dimanlhatlmn sebagai sayuran yang memiliki kandungan protein tinggi. Ubi jalar (Ipomoea balalas) berasal dari Amerika Selatan bagian Barat Daya, sedangkan Ipomoea Iriflda berasal dari Amerika tropik. Penelitian ini bertujuan mempelajari kemampuan silang antara Ipomoea balalas berdaging umbi ungu dengan kerabat liarnya (Ipomoea Iriflda). Tanaman yang digunakan dalmn peneIitian ini terdiri dari tujuh klan tanaman ubi jalar berdaging umbi ungu (BOlO, B083, BI07, GI4, G25, W22, dan W29) sebagai tetua betina dan satu klan tanaman Ipomoea triflda, Jt(2). sebagai tetua jantan. Umur berbunga klan tetua betina tanaman ubi jalar bcrdaging umbi ungu hampir seragam. Klan B083 dan G14 merupakan klan yang berbunga paling awal sedangkan klan W22 dan W29 merupakan klan yang berbunga paling lamba!. Dari tujuh klan tanaman ubi jalar berdaging umbi ungu hanya empat klan yang menghasilkan kapsul biji (B083, B107, GI4, dan W22). Klan tetua GI4 menghasilkan jumlah kapsul terbanyak. 23 kapsul dcngan 1-2 biji per kapsul. Scmua tanaman hasH silangan mempunyai kemampuan berumbi (100%). Klan zuriat nomor 22, 25, dan 44 menghasilkan daging umbi berwarna kuning, sedangkan klan zariat nomor 35 menghasilkan daging umbi berwarna ungu. Pengamatan jumlah kromosom menunjukkan bahwa klon B083 dan W22 memiliki jumlah kromosom 90. tanaman It(2) memiIiki jumlah kromosom 30 dan tanaman zuriat hasil silangan memiliki jumlah kromosom 60.
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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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