Judul: Pembersihan Isi Sel Akar dan Jenis Warna Tinta untuk Deteksi Cendawan Mikoriza Arbuskula
Abstrak: Arbuscular mycorrhizal (AM) fungi is a symbiotic mutualistic fungi association with plant roots. Staining technique to detect AM fungi usually used hazardous chemical. The ink stain and vinegar were used as alternative technique to replace trypan blue and lactic acid in root staining method. This study aimed to determine time of clearing of root cell contents and types of ink stain to produced the best AM fungal structures within the root observed under microscope. Pueraria javanica root from 6 pot cultures were cut into 1 cm long. They were cleared and stained using 4 types of stains. Twenty stained roots were taken randomly from each stain types, and observed. Root clearing process for 20 minutes showed the best result. Only shaeffer black ink and trypan blue produced clear structure of external hyphae, internal hyphae, vesicles, and arbuscule. Arbuscular structure only stained by shaeffer black ink and trypan blue. This indicated that shaeffer black ink could be used as an alternative stain to detect AM fungi within the P. javanica root.
Keyword: 

Judul: Keanekaragaman Fungi Mikoriza Arbuskula di bawah Tegakan Tanaman Agroforestri Jabon (Anthocephalus cadamba Miq.) di Purwakarta, Jawa Barat
Abstrak: Anthocephalus cadamba is a one of tree species from Rubiaceae family that may symbiotic with arbuscular mycorrhizal fungi (AMF). The presence of AMF is very important for the soil nutrient existence, such as P, K, Mg, Fe, and also Mn to increase the growth of plants. The purpose of this research is to identify the diversity of AMF spores under stand of jabon agroforestry plants and to analyze the AMF status on various jabon planting patterns. Spores isolation was taken from soil sample using wet sieving method and decanthing method. Spores from the isolation morfologically identified by observing spores reaction through Melzer’s liquid. The result of this research indicated that soil chemical characteristic on three planting patterns of jabon do not give any concrete effects to the percentage of AMF’s root colonization. There are three genus of AMF found on the research location consist of Glomus sp., Acalauspora sp., and Scutellospora sp. Based on statistical analysis result, the jabon intercropping planting patterns which combining cucumber plants resulting the highest value of both diameter and height growth on various jabon planting patterns.
Keyword: root colonization, planting pattern, arbuscular mycorrhizal fungi

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.
Keyword: