Judul: Cendawan Mikoriza Arbuskula pada Kecapi (Sandoricum koetjape) di LIPI Cibinong
Abstrak: Research on the association of arbuscular mycorrhizal fungi (AMF) with plants fruits are still rarely done and kechapi (Sandoricum koetjape) is one of the plants that has not been studied. This study aims to identify AMF and arbuscular mycorrhiza structures on kechapi. Spores isolated from the rhizosphere soil samples of kechapi and pot culture. Spores were isolated by wet sieving and decanting method followed by centrifugation then later identified. Observations of arbuscular mycorrhiza structure on roots done by staining using trypan blue then observed structures of arbuscular, coiled hyphae, internal hyphae, and vesicles. The result showed that the percentage infection of roots of kechapi is 36-50%, and the structures of infections in roots of kechapi were coiled hyphae, internal hyphae, and vesicles. The genera of AMF assosiated with kechapi were Acaulospora, Funneliformis, Gigaspora, and Glomus
Keyword: Sandoricum koetjape, Glomus, Gigaspora, Funneliformis, arbuscular mycorrhizal fungi, Acaulospora

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: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model