Judul: Pengelompokan Varietas/Galur Sorgum (Sorghum bicolor (L.) Moench) Berdasarkan Ciri-Ciri Morfologinya
Abstrak: Tanaman Sorgum dapat dijadikan altematif sumber bahan pangan, pakan ternak, bahan baku lem dan sapu. Tanaman ini reIatif Iebih resisten terhadap lingkungan yang kurang subur dibandingkan tanaman sumber bah an pangan lainnya sehingga sorgum berpotensi untuk dikembangkan di Indonesia. Pemuliaan sorgum perIu diupayakan. Upaya persilangan antar varietas/galur sorgum menjadi lcbih efisien dcngan adanya informasi kelompok-kelompok sorgum berdasarkan kesamaan ciri morfologinya.
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Judul: Karakterisasi Sorgum Varietas Lokal, Varietas Nasional dan Galur-Galur Hasil Pemuliaan
Abstrak: Sorgum merupakan tanaman serealia yang memiliki banyak manfaat dan daya adaptasi luas. Salah satu permasalahan dalam pengembangan tanaman sorgum adalah terbatasnya varietas yang dapat dikembangkan secara komersial sesuai spesifik kebutuhan. Indonesia memiliki beberapa varietas sorgum jenis lokal, nasional, dan hasil pemuliaan yang memiliki keunggulan masing-masing. Genotipe-genotipe ini perlu dikarakterisasi lebih mendalam agar berbagai keunggulannya dapat dimanfaatkan secara maksimal. Penelitian dilaksanakan pada November 2019 – Maret 2020 di Kebun Percobaan Leuwikopo IPB. Genotipe sorgum yang diamati memiliki karakter agronomis beragam pada panjang daun, lebar daun, tinggi tanaman, diameter batang, waktu berbunga, panjang malai, panjang cabang malai, panjang leher malai, bobot malai kering, bobot biji per malai, dan bobot 1000 butir. Genotipe sorgum yang diamati memiliki karakter morfologis beragam pada intensitas antosianin koleoptil, intensitas hijau daun, warna tulang daun, intensitas antosianin sekam, warna putik, panjang putik, kerapatan malai, warna benang sari kering, bentuk malai, warna sekam, panjang sekam, ukuran embrio, bentuk biji, warna biji, warna endosperm, dan tekstur endosperm. Analisis gerombol membentuk 3 kelompok, yaitu kelompok 1 (Numbu, Bioguma 1, A-125-1-6-1, Kawali, Soraya, dan PI-150-20A), Kelompok 2 (Pahat), dan Kelompok 3 (Pulut 2, Pulut 3, dan Pulut 4).
Keyword: adaptasi, analisis gerombol, genotipe, karakter, keragaman

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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